Heating of high-rise buildings. Heat supply and heating of high-rise buildings

Send your good work in the knowledge base is simple. Use the form below

Students, graduate students, young scientists who use the knowledge base in their studies and work will be very grateful to you.

Posted on http:// www. allbest. ru/

Ministry of Education of the Republic of Belarus

Belarusian National Technical University

Faculty of Energy Construction

Department of Heat and Gas Supply and Ventilation

on the topic: "Heat supply and heating high-rise buildings"

Prepared by: student gr. No. 11004414

Novikova K.V.

Checked by: Nesterov L.V.

Minsk - 2015

Introduction

If the temperature conditions in a room or building are favorable, then heating and ventilation specialists are somehow not remembered. If the situation is unfavorable, then specialists in this field are the first to be criticized.

However, the responsibility for maintaining the specified parameters in the room does not lie only with heating and ventilation specialists.

Adoption engineering solutions to ensure the specified parameters in the room, the volume of capital investments for these purposes and subsequent operating costs depend on space-planning decisions taking into account an assessment of the wind regime and aerodynamic parameters, construction solutions, orientation, building glazing coefficient, calculated climatic indicators, including quality, pollution levels atmospheric air based on the totality of all sources of pollution. Multifunctional high-rise buildings and complexes are extremely complex structures from the point of view of designing engineering communications: heating systems, general exchange and smoke ventilation, general and fire water supply, evacuation, fire automatics, etc. This is mainly due to the height of the building and the permissible hydrostatic pressure, in particular in water heating, ventilation and air conditioning systems.

All buildings can be divided into 5 categories based on height:

* up to five floors where installation of elevators is not required - low-rise buildings;

* up to 75 m (25 floors), within which vertical zoning into fire compartments is not required - multi-storey buildings;

* 76-150 m - high-rise buildings;

* 151-300 m - high-rise buildings;

* over 300 m - super-tall buildings.

The gradation is a multiple of 150 m due to a change in the calculated temperature of the outside air for designing heating and ventilation - every 150 m it decreases by 1 °C.

When installing it in the basement, only part of the floor located on the border of the fire compartments can be used to accommodate smoke protection fans, the rest - for work rooms. With a cascade scheme for connecting heat exchangers, as a rule, they, together with pumping groups, are placed on technical floors, where they require more space, and occupy the entire floor, and in super-tall buildings sometimes two floors.

Below we will give an analysis of design solutions for heat and water supply and heating of the listed residential buildings.

1. Heat supply

Heat supply internal systems heating, hot water supply, ventilation, air conditioning of high-rise buildings is recommended to provide:

From district heating networks;

from an autonomous heat source (AHS), subject to confirmation of the admissibility of its impact on the environment in accordance with current environmental legislation and regulatory and methodological documents;

from a combined heat source (CHS), including hybrid heat pump heat supply systems using non-traditional renewable energy sources and secondary energy resources (soil, building ventilation emissions, etc.) in combination with heat and/or electrical networks.

Heat consumers of high-rise buildings are divided into two categories based on the reliability of heat supply:

the first - heating, ventilation and air conditioning systems for premises in which, in the event of an accident, interruptions in the supply of the calculated amount of heat and a decrease in air temperature below the minimum permissible according to GOST 30494 are not allowed. The list of these premises and the minimum permissible air temperature in the premises must be given in the Technical Specifications;

the second - other consumers for whom it is allowed to reduce the temperature in heated premises for the period of liquidation of the accident for no more than 54 hours, not lower than:

16C - in residential premises;

12C - in public and administrative premises;

5C - in production premises.

The heat supply of a high-rise building should be designed to ensure uninterrupted heat supply in case of accidents (failures) at the heat source or in the supply heating networks during the repair and restoration period from two (main and backup) independent inputs of the heating networks. 100% supply must be provided from the main input required quantity heat for a high-rise building; from the backup input? supply of heat in an amount not less than that required for heating and ventilation and air conditioning systems of consumers of the first category, as well as heating systems of the second category to maintain the temperature in heated premises not lower than that specified above. By the beginning of the operating cycle, the air temperature in these rooms must correspond to the standard.

Internal heating systems should be connected:

with centralized heating? according to an independent circuit to heating networks;

with AIT? according to a dependent or independent scheme.

Internal heat supply systems must be divided according to the height of buildings into zones (zoned). The height of the zone should be determined by the value of the permissible hydrostatic pressure in the lower elements of the heat supply systems of each zone.

The pressure at any point in the heat supply systems of each zone under hydrodynamic conditions (both at the design flow rates and water temperature, and with possible deviations from them) must ensure that the systems are filled with water, prevent boiling of water and not exceed the value permissible in terms of strength for equipment (heat exchangers, tanks, pumps, etc.), fittings and pipelines.

Water supply to each zone can be carried out in a sequential (cascade) or parallel circuit through heat exchangers with automatic control of the temperature of the heated water. For heat consumers of each zone, it is necessary, as a rule, to provide their own circuit for the preparation and distribution of coolant with a temperature regulated according to an individual temperature schedule. When calculating the temperature schedule of the coolant, the beginning and end of the heating period should be taken at the average daily outside air temperature of +8C and the average design air temperature in heated rooms.

For heat supply systems of high-rise buildings, it is necessary to provide equipment redundancy according to the following scheme.

In each coolant preparation circuit, at least two heat exchangers (working + backup) should be installed, the heating surface of each of which should provide 100% of the required heat consumption for heating, ventilation, air conditioning and hot water supply systems.

When installing backup cylinder electric heaters in the hot water preparation circuit, redundancy of heat exchangers DHW systems may not be provided.

It is allowed to install three heat exchangers (2 working + 1 reserve) in the coolant preparation circuit for the ventilation system, the heating surface of each of which must provide 50% of the required heat consumption for ventilation and air conditioning systems.

With a cascade heat supply scheme, the number of heat exchangers for heat supply to the upper zones is allowed to be 2 working + 1 reserve, and the heating surface of each should be 50% or according to the technical specifications.

Heat exchangers, pumps and other equipment, as well as fittings and pipelines should be selected taking into account the hydrostatic and operating pressure in the heating system, as well as the maximum test pressure during hydraulic testing. The operating pressure in the systems should be 10% below the permissible operating pressure for all system elements.

The coolant parameters in heat supply systems, as a rule, should be taken taking into account the temperature of the heated water in the zonal heat exchangers of the water preparation circuit of the corresponding zone along the height of the building. The coolant temperature should be no more than 95 C in systems with pipelines made of steel or copper pipes and no more than 90 C - from polymer pipes approved for use in heat supply systems. Coolant parameters in internal heat supply systems are allowed to be more than 95 C, but not more than 110 C in systems with pipelines made of steel pipes taking into account checking that the transported water does not boil over the height of the building. When laying pipelines with a coolant temperature of more than 95 C, they should be laid in separate or shared with other pipelines, fenced off shafts, taking into account appropriate safety measures. Laying of the specified pipelines is possible only in places accessible to the operating organization. Measures should be taken to prevent steam from entering outside the technical premises if pipelines are damaged.

A feature of the design of heat and water supply systems is that all pumping and heat exchange equipment of the high-rise residential buildings under consideration is located at ground level or minus the first floor. This is due to the danger of placing superheated water pipelines on residential floors, uncertainty about the adequacy of protection from noise and vibration of adjacent residential premises during operation pumping equipment and the desire to preserve scarce space to accommodate more apartments.

This solution is possible thanks to the use of high-pressure pipelines, heat exchangers, pumps, shut-off and control equipment that can withstand operating pressures of up to 25 atm. Therefore, when piping heat exchangers on the local water side, they use butterfly valves with collar flanges, pumps with a U-shaped element, direct-acting downstream pressure regulators installed on the make-up pipeline, solenoid valves, designed for a pressure of 25 atm. in the heating system filling station.

When the height of buildings is above 220 m, due to the occurrence of ultra-high hydrostatic pressure, it is recommended to use a cascade scheme for connecting zonal heat exchangers for heating and hot water supply. Another feature of the heat supply of implemented high-rise residential buildings is that in all cases the source of heat supply is city heating networks. Connection to them is made through a central heating station, which occupies a fairly large area. The central heating system includes heat exchangers with circulation pumps for heating systems of different zones, heat supply systems for ventilation and air conditioning heaters, hot water supply systems, pumping stations filling heating systems and pressure maintenance systems with expansion tanks and automatic regulation equipment, emergency electric storage water heaters for hot water supply. Equipment and pipelines are located vertically so that they are easily accessible during operation. A central passage with a width of at least 1.7 m passes through all central heating centers to allow the movement of special loaders, allowing the removal of heavy equipment when replacing it (Fig. 1).

This decision is also due to the fact that high-rise complexes, as a rule, are multifunctional in purpose with a developed stylobate and underground part, on which several buildings can be located. Therefore, in the complex, which includes 3 high-rise residential buildings with 43-48 floors and 4 buildings with a height of 17-25 floors, united by a five-level stylobate part, technical collectors with numerous pipelines depart from this single central heating center, and to reduce them, they placed booster water supply pumping stations that pump cold and hot water into each zone of high-rise buildings.

Another solution is also possible - the central heating station serves to introduce urban heating networks to the facility, place a pressure differential regulator "after itself", a heat metering unit and, if necessary, a cogeneration installation and can be combined with one of the individual local heating points (ITP), serving to connect local heat consumption systems close in location to a given heating point. From this central heating station, superheated water is supplied through two pipes, and not through several from the comb, as in the previous case, to local ITPs located in other parts of the complex, including on the upper floors, according to the principle of proximity to the thermal load. With this solution, there is no need to connect the internal heat supply system to the supply air heaters according to an independent circuit through a heat exchanger. The heater itself is a heat exchanger and is connected directly to the superheated water pipelines with pump mixing to improve the quality of load control and increase the reliability of the heater protection from freezing.

One of the solutions for reserving centralized heat and power supply to high-rise buildings may be the construction of autonomous mini-CHPs based on gas turbine (GTU) or gas piston (GPU) units that simultaneously generate both types of energy. Modern means protection from noise and vibration allow them to be placed directly in the building, including on the upper floors. As a rule, the power of these installations does not exceed 30-40% of the maximum required power of the facility and in normal mode these installations operate, complementing centralized energy supply systems. With greater power of cogeneration plants, problems arise in transferring excess energy carriers to the network.

There is literature that provides an algorithm for calculating and selecting mini-CHPs for power supply to an object in autonomous mode and an analysis of the optimization of the choice of mini-CHPs using the example of a specific project. If there is a shortage of only thermal energy for the object in question, an autonomous heat supply source (AHS) in the form of a boiler room with hot water boilers. Attached, located on the roof or protruding parts of the building, or free-standing boiler rooms designed in accordance with SP 41-104-2000 can be used. The possibility and location of AIT should be linked to the entire complex of its impact on environment, including for a residential high-rise building.

The temperature situation in the room is significantly influenced by the area and thermal performance of the glazed surface. It is known that the standard reduced heat transfer resistance of windows is almost 6 times less than the reduced heat transfer resistance of external walls. In addition, through them per hour, if there are no sun protection devices, up to 300 - 400 W/m2 of heat comes through solar radiation. Unfortunately, when designing administrative and public buildings the glazing coefficient may be exceeded by 50% if there is appropriate justification (with a heat transfer resistance of at least 0.65 m2°C / W). In fact, it is possible to use this assumption without appropriate justification.

2. Heating

The following heating systems can be used in high-rise buildings:

water two-pipe with horizontal distribution across floors or vertical;

air with heating and recirculation units within one room or combined with a mechanical supply ventilation system;

electrical according to design specifications and upon receipt technical specifications from the energy supply organization.

It is allowed to use underfloor (water or electric) heating to heat bathrooms, locker rooms, swimming pool areas, etc.

The parameters of the coolant in the heating systems of the corresponding zone should be taken according to SP 60.13330 no more than 95C in systems with pipelines made of steel or copper pipes and no more than 90C? from polymer pipes approved for use in construction.

The height of the heating system zone should be determined by the permissible hydrostatic pressure in the lower elements of the system. The pressure at any point in the heating system of each zone in hydrodynamic mode must ensure that the systems are filled with water and not exceed the permissible strength value for equipment, fittings and pipelines.

Devices, fittings and pipelines of heating systems should be selected taking into account the hydrostatic and operating pressure in the heating system of the zone, as well as the maximum test pressure during hydraulic testing. The operating pressure in the systems should be 10% below the permissible operating pressure for all system elements.

Air-thermal regime of a high-rise building

When calculating the air regime of a building, depending on the configuration of the building, the influence of vertical wind speed on the facades, at the roof level, as well as the pressure difference between the windward and leeward facades of the building are assessed.

The design parameters of outdoor air for heating, ventilation, air conditioning, heat and cold supply systems of a high-rise building should be taken according to the technical specifications, but not lower than parameters B according to SP 60.13330 and SP 131.13330.

Calculations of heat loss by external enclosing structures, air conditions of high-rise buildings, parameters of external air at the locations of air intake devices, etc. should be carried out taking into account changes in the speed and temperature of external air along the height of buildings in accordance with Appendix A and SP 131.13330.

Outdoor air parameters should be taken taking into account the following factors:

decrease in air temperature in altitude by 1 °C for every 100 m;

increased wind speed during the cold season;

the appearance of powerful convective flows on building facades irradiated by the sun;

placement of air intake devices in the high-rise part of the building.

When placing receiving devices for outside air on the southeast, south or southwest facades, the outside air temperature in the warm season should be taken 3-5 C higher than the calculated one.

The calculated parameters of the microclimate of the internal air (temperature, movement speed and relative humidity) in residential, hotel and public premises of high-rise buildings should be taken within the limits optimal standards according to GOST 30494

During the cold season in residential, public, administrative and industrial premises ( refrigeration units, elevator machine rooms, ventilation chambers, pump rooms, etc.), when they are not in use and during non-working hours, it is allowed to reduce the air temperature below the normalized one, but not less than:

16C? in residential premises;

12C? in public and administrative premises;

5C? in production premises.

By the beginning of working hours, the air temperature in these rooms must correspond to the standard.

At the entrance vestibules of high-rise buildings, as a rule, double airlocking of the hall or vestibule should be provided. As entrance doors It is recommended to use airtight devices of a circular or radius type.

Measures should be taken to reduce air pressure in vertical elevator shafts, which is formed along the height of the building due to the gravitational difference, as well as to eliminate unorganized flows of internal air between individual functional areas building.

Water heating systems of high-rise buildings are zoned by height and, as already mentioned, if fire compartments are separated by technical floors, then the zoning of heating systems, as a rule, coincides with fire compartments, since technical floors are convenient for laying distribution pipelines. In the absence of technical floors, the zoning of heating systems may not coincide with the division of the building into fire compartments. Fire inspection authorities allow pipelines of water-filled systems to cross the boundaries of fire compartments, and the height of the zone is determined by the value of the permissible hydrostatic pressure for the lower heating devices and their piping.

Initially, the design of zone heating systems was carried out as for conventional multi-storey buildings. As a rule, two-pipe heating systems with vertical risers and bottom wiring supply and return lines running along the technical floor, which made it possible to turn on the heating system without waiting for the construction of all floors of the zone. Such heating systems have been implemented, for example, in residential complexes" Scarlet Sails", "Vorobyovy Gory", "Triumph Palace" (Moscow). Each riser is equipped with automatic balancing valves to ensure automatic distribution of coolant throughout the risers, and each heating device is equipped with an automatic thermostat with increased hydraulic resistance to provide the resident with the opportunity to set the temperature he needs air in the room and minimizing the influence of the gravitational component of the circulation pressure and turning on/off thermostats on other heating devices connected to this riser.

Further, in order to avoid imbalance of the heating system associated with the unauthorized removal of thermostats in individual apartments, which has repeatedly occurred in practice, it was proposed to switch to a heating system with an upper distribution of the supply line with passing traffic coolant through risers. This equalizes the pressure loss of the circulation rings through heating devices regardless of which floor they are located on, it increases the hydraulic stability of the system, guarantees the removal of air from the system and facilitates the setting of thermostats.

However, subsequently, as a result of the analysis various solutions, the designers came to the conclusion that the best system heating systems, especially for buildings without technical floors, are systems with apartment-by-apartment horizontal wiring, connected to vertical risers, passing, as a rule, along staircase, and made according to a two-pipe scheme with lower routing of lines. For example, such a system was designed in the crowning part (9 floors of the third zone) of the Triumph Palace high-rise complex and in a 50-story building under construction without intermediate technical floors.

Apartment heating systems are equipped with a unit with a shut-off valve that is regulated using balancing valves and drain fittings, filters and a thermal energy meter. This unit should be located outside the apartment on the staircase for unhindered access by the maintenance service. In apartments over 100 m2, the connection is not made with a loop perimeter laid around the apartment (since as the load increases, the diameter of the pipeline increases, and as a result, installation becomes more complicated and the cost increases due to the use of expensive fittings big size), and through the intermediate apartment distribution cabinet in which the comb is installed, and from it the coolant is directed through a radial circuit through pipelines of smaller diameter to the heating devices according to a two-pipe circuit.

Pipelines are used from heat-resistant polymer materials, usually made of cross-linked polyethylene PEX, the laying is done in preparation of the floor. The calculated parameters of the coolant, based on the technical conditions for such pipelines, are 90-70 (65) °C due to the fear that a further decrease in temperature leads to a significant increase in the heating surface of heating devices, which is not welcomed by investors due to the rising cost of the system. Application experience metal-plastic pipes in the heating system of the complexes was considered unsuccessful. During operation, it deteriorates as a result of aging. adhesive layer And inner layer the pipe “collapses”, as a result of which the flow area narrows and the heating system stops working normally.

Some experts believe that for apartment wiring, the optimal solution is to use automatic balancing valves ASV-P (PV) on the return pipeline and shut-off and measuring valves ASV-M (ASV-1) on the supply pipeline. The use of this pair of valves makes it possible not only to compensate for the influence of the gravitational component, but also to limit the flow rate for each apartment in accordance with the parameters. Valves are usually selected according to the diameter of the pipelines and are set to maintain a pressure drop of 10 kPa. This valve setting value is selected based on the required pressure loss on radiator thermostats to ensure their optimal operation. The limitation of flow per apartment is set by the settings on the ASV-1 valves, and it is taken into account that in this case the pressure loss on these valves must be included in the pressure difference maintained by the ASV-PV regulator. heat supply temperature water heating

Application of door-to-door horizontal systems heating compared to a system with vertical risers leads to a reduction in the length main pipes wires (they fit only to the stair riser, and not to the most distant riser in corner room), reducing heat loss through pipelines, simplifying the floor-by-floor commissioning of the building and increasing the hydraulic stability of the system. The cost of installing an apartment-by-apartment system is not much different from standard ones with vertical risers, but the service life is longer due to the use of pipes made of heat-resistant polymer materials.

IN apartment systems heating system, it is much simpler and with absolute clarity for residents that heat energy can be metered. We must agree with the opinion of the authors that although the installation of heat meters does not relate to energy-saving measures, however, payment for actually consumed thermal energy is a powerful incentive forcing residents to use it carefully. Naturally, this is achieved, first of all, by the mandatory use of thermostats on heating devices. The experience of their operation has shown that in order to avoid influencing the thermal conditions of adjacent apartments, the thermostat control algorithm should include a limitation of reducing the temperature in the room they serve to no lower than 15-16 ° C, and heating devices should be selected with a power reserve of at least 15%.

These are the solutions for heat supply and heating systems of the tallest residential buildings built to date. They are clear, logical and do not fundamentally differ from the solutions used in the design of conventional multi-storey buildings less than 75 m in height, with the exception of the division of heating and water supply systems into zones. But within each zone, standard approaches to implementing these systems are retained. Appeals more attention to installations for filling heating systems and maintaining pressure in them, as well as in circulation lines from different zones before connecting them to a common comb, automatic regulation of heat supply and distribution of coolant to implement comfortable and economical modes, redundant operation of equipment to ensure an uninterrupted supply of heat to consumers.

The disadvantages of the decisions made include ignoring the use of energy-saving solutions, such as partial replacement of energy demand through the use of autonomous energy-producing gas turbine or gas piston units, solar photovoltaic or water heating elements, heat pumps using low-potential soil energy, and ventilation emissions. It should also be noted that there is insufficient use of centralized refrigeration to improve the comfort of living in apartments and eliminate the negative impact on the architecture of the building of external split-system units haphazardly hung on the facade. High-rise buildings, being advanced in terms of architectural and structural solutions, should be an example for the implementation of promising technologies in engineering systems. During the installation and manufacture of units and parts of heat supply and heating systems with water temperatures above 388 K (115 ° C) and steam with a working pressure of more than 0.07 MPa (0.7 kgf/cm).

To protect against electrochemical corrosion and stray currents, fastening devices for metal elements of all systems and assemblies passing through building construction must be electrically insulated. Main pipelines and risers must be grounded. A combination of materials forming an electrochemical couple is not allowed.

The durability of equipment must be at least 12 years, materials - 25 years.

Development project documentation must be preceded by the development and approval of special technical conditions.

Bibliography

1. Anapolskaya L.E., Gandin L.S. Meteorological factors of the thermal regime of buildings. Gidrometeoizdat. Leningrad. 1973.

2.SNiP 21-01-97* " Fire safety buildings and structures."

3.Shilkin N.V. Problems of high-rise buildings // ABOK No. 6, 1999.

Posted on Allbest.ru

...

Similar documents

Categorization of high-rise buildings and compilation of their ratings. Three criteria for measuring the height of a building. The history of skyscrapers is very tall buildings with a load-bearing steel frame. Structural diagrams of high-rise buildings. Various options for composite steel columns.

presentation, added 03/06/2015

Architectonics as artistic expression structural patterns building structures. Concept and types of structural systems. Barrel systems of high-rise buildings. Architectonics of high-rise buildings, its principles and significance, directions of research.

abstract, added 10/27/2013

Studying the concept of “high-rise building” - a building whose height is greater than the regulated SNiP for residential multi-apartment, as well as multi-storey public and multi-functional buildings. Architectural organization of high-rise residential buildings and high-rise complexes.

abstract, added 11/09/2010

General rules carrying out inspections and monitoring of the technical condition of buildings and structures. Monitoring buildings in disrepair. Examples of design and operation of monitoring schemes for structures and foundations of high-rise buildings.

abstract, added 06/11/2011

Duration of standing intervals of outdoor air temperature according to climatological data of the city of Astrakhan. Calculation of heating modes, heat pump installation in heat supply system mode. Cooling mode of the air conditioning system.

test, added 02/07/2013

Methods of heat supply for administrative buildings. Schemes and equipment of heating networks. Properties of coolants. Hydraulic calculation of heating network gas pipelines. Characteristics of a gas boiler room, calculation of its parameters depending on the heat loss of the room.

thesis, added 03/22/2018

High-rise buildings and the history of their construction. Building classification criteria. Classification of structural systems of skyscrapers. Features of the technology for constructing high-rise buildings of the shell system. Characteristics of materials required for construction.

essay, added 09/24/2016

Basic requirements for modern industrial buildings. Space-planning solutions for industrial buildings. Types of multi-storey industrial buildings. Cellular and hall industrial building. Unified parameters of one-story industrial buildings.

presentation, added 12/20/2013

Selection, placement and laying of main pipes, risers and heating devices. Placement of shut-off and control valves. Removing air from the heating system. Compensation for thermal expansion of pipes. Calculation of the main and small circulation rings.

course work, added 03/26/2012

Fundamentals of industrial plant design. In-shop lifting and transport equipment. Unification in industrial construction. Modular system and building parameters. Steel frame of one-story buildings. Requirements for walls and their classification.

Ministry of Education of the Republic of Belarus

Belarusian National Technical University

Faculty of Energy Construction

Department of Heat and Gas Supply and Ventilation

on the topic: "Heat supply and heating of high-rise buildings"

Prepared by: student gr. No. 11004414

Novikova K.V.

Checked by: Nesterov L.V.

Minsk – 2015

Introduction

However, the responsibility for maintaining the specified parameters in the room does not lie only with heating and ventilation specialists.

The adoption of engineering decisions to ensure the specified parameters in the room, the volume of capital investments for these purposes and subsequent operating costs depend on space-planning decisions taking into account the assessment of wind conditions and aerodynamic parameters, construction solutions, orientation, building glazing coefficient, calculated climatic indicators, including including quality, level of air pollution based on the totality of all sources of pollution. Multifunctional high-rise buildings and complexes are extremely complex structures from the point of view of designing engineering communications: heating systems, general and smoke ventilation, general and fire water supply, evacuation, fire automatics, etc. This is mainly due to the height of the building and the permissible hydrostatic pressure, in particular , in water heating, ventilation and air conditioning systems.

All buildings can be divided into 5 categories based on height:

Up to five floors where installation of elevators is not required - low-rise buildings;

Up to 75 m (25 floors), within which vertical zoning into fire compartments is not required - multi-storey buildings;

76–150 m – high-rise buildings;

151–300 m – high-rise buildings;

Over 300 m – super-tall buildings.

The gradation multiple of 150 m is due to a change in the calculated temperature of the outside air for designing heating and ventilation - every 150 m it decreases by 1 °C.

When installing it in the basement, only part of the floor located on the border of the fire compartments can be used to accommodate smoke protection fans, the rest for work spaces. With a cascade scheme for connecting heat exchangers, as a rule, they, together with pumping groups, are placed on technical floors, where they require more space, and occupy the entire floor, and in super-tall buildings sometimes two floors.

Below we will give an analysis of design solutions for heat and water supply and heating of the listed residential buildings.

1. Heat supply

It is recommended to provide heat supply for internal heating systems, hot water supply, ventilation, and air conditioning of high-rise buildings:

From district heating networks;

Heat consumers of high-rise buildings are divided into two categories based on the reliability of heat supply:

the first is the heating, ventilation and air conditioning systems of premises in which, in the event of an accident, interruptions in the supply of the calculated amount of heat and a decrease in air temperature below the minimum permissible according to GOST 30494 are not allowed. The list of these premises and the minimum permissible air temperature in the premises must be given in the Technical Specifications;

the second - other consumers for whom it is allowed to reduce the temperature in heated premises for the period of liquidation of the accident for no more than 54 hours, not lower than:

16С – in residential premises;

12С – in public and administrative premises;

5С – in production premises.

The heat supply of a high-rise building should be designed to ensure uninterrupted heat supply in case of accidents (failures) at the heat source or in the supply heating networks during the repair and restoration period from two (main and backup) independent inputs of the heating networks. The main input must supply 100% of the required amount of heat for a high-rise building; from the reserve input - supply of heat in an amount not less than required for heating and ventilation and air conditioning systems of consumers of the first category, as well as heating systems of the second category to maintain the temperature in heated premises not lower than that specified above. By the beginning of the operating cycle, the air temperature in these rooms must correspond to the standard.

Internal heating systems should be connected:

with centralized heat supply - according to an independent scheme to heating networks;

for AIT - according to a dependent or independent scheme.

Water supply to each zone can be carried out in a sequential (cascade) or parallel circuit through heat exchangers with automatic control of the temperature of the heated water. For heat consumers of each zone, it is necessary, as a rule, to provide their own circuit for the preparation and distribution of coolant with a temperature regulated according to an individual temperature schedule. When calculating the temperature schedule of the coolant, the beginning and end of the heating period should be taken at an average daily outside air temperature of +8°C and an average design air temperature in heated rooms.

For heat supply systems of high-rise buildings, it is necessary to provide equipment redundancy according to the following scheme.

When installing backup capacitive electric heaters in the hot water preparation circuit, redundancy of heat exchangers of DHW systems may not be provided.

The coolant parameters in heat supply systems, as a rule, should be taken taking into account the temperature of the heated water in the zonal heat exchangers of the water preparation circuit of the corresponding zone along the height of the building. The coolant temperature should be no more than 95 °C in systems with pipelines made of steel or copper pipes and no more than 90 °C - from polymer pipes approved for use in heat supply systems. The parameters of the coolant in internal heat supply systems are allowed to be more than 95 °C, but not more than 110 °C in systems with pipelines made of steel pipes, taking into account the check that the water being moved does not boil over the height of the building. When laying pipelines with a coolant temperature of more than 95 °C, they should be laid in separate or shared with other pipelines, fenced off shafts, taking into account appropriate safety measures. Laying of the specified pipelines is possible only in places accessible to the operating organization. Measures should be taken to prevent steam from entering outside the technical premises if pipelines are damaged.

A feature of the design of heat and water supply systems is that all pumping and heat exchange equipment of the high-rise residential buildings under consideration is located at ground level or minus the first floor. This is due to the danger of placing superheated water pipelines on residential floors, uncertainty about the adequacy of protection from noise and vibration of adjacent residential premises during operation of pumping equipment, and the desire to preserve scarce space to accommodate a larger number of apartments.

This solution is possible thanks to the use of high-pressure pipelines, heat exchangers, pumps, shut-off and control equipment that can withstand operating pressures of up to 25 atm. Therefore, when piping heat exchangers on the local water side, they use butterfly valves with collar flanges, pumps with a U-shaped element, direct-acting “upstream” pressure regulators installed on the make-up pipeline, and solenoid valves designed for a pressure of 25 atm. in the heating system filling station.

When the height of buildings is above 220 m, due to the occurrence of ultra-high hydrostatic pressure, it is recommended to use a cascade scheme for connecting zonal heat exchangers for heating and hot water supply. Another feature of the heat supply of implemented high-rise residential buildings is that in all cases the source of heat supply is city heating networks. Connection to them is made through a central heating station, which occupies a fairly large area. The central heating system includes heat exchangers with circulation pumps for heating systems in different zones, heat supply systems for ventilation and air conditioning heaters, hot water supply systems, pumping stations for filling heating systems and pressure maintenance systems with expansion tanks and auto-regulation equipment, emergency electric storage water heaters for hot water supply. Equipment and pipelines are located vertically so that they are easily accessible during operation. A central passage with a width of at least 1.7 m passes through all central heating centers to allow the movement of special loaders, allowing the removal of heavy equipment when replacing it (Fig. 1).

This decision is also due to the fact that high-rise complexes, as a rule, are multifunctional in purpose with a developed stylobate and underground part, on which several buildings can be located. Therefore, in the complex, which includes 3 high-rise residential buildings with 43–48 floors and 4 buildings with a height of 17–25 floors, united by a five-level stylobate part, technical collectors with numerous pipelines depart from this single central heating center, and to reduce them, they placed booster water supply pumping stations that pump cold and hot water into each zone of high-rise buildings.

One of the solutions for reserving centralized heat and power supply to high-rise buildings may be the construction of autonomous mini-CHPs based on gas turbine (GTU) or gas piston (GPU) units that simultaneously generate both types of energy. Modern means of protection against noise and vibration make it possible to place them directly in the building, including on the upper floors. As a rule, the power of these installations does not exceed 30–40% of the maximum required power of the facility and in normal mode these installations operate, complementing the centralized energy supply systems. With greater power of cogeneration plants, problems arise in transferring excess energy carriers to the network.

There is literature that provides an algorithm for calculating and selecting mini-CHPs for power supply to an object in autonomous mode and an analysis of the optimization of the choice of mini-CHPs using the example of a specific project. If there is a shortage of only thermal energy for the object under consideration, an autonomous heat supply source (AHS) in the form of a boiler room with hot water boilers can be accepted as a source of heat supply. Attached, located on the roof or protruding parts of the building, or free-standing boiler rooms designed in accordance with SP 41-104-2000 can be used. The possibility and location of AIT should be linked to the entire complex of its impact on the environment, including on a residential high-rise building.

The temperature situation in the room is significantly influenced by the area and thermal performance of the glazed surface. It is known that the standard reduced heat transfer resistance of windows is almost 6 times less than the reduced heat transfer resistance of external walls. In addition, through them per hour, if there are no sun protection devices, up to 300 - 400 W/m2 of heat due to solar radiation. Unfortunately, when designing administrative and public buildings, the glazing factor can be exceeded by 50% if there is appropriate justification (with a heat transfer resistance of at least 0.65 m2°C / W). In fact, it is possible to use this assumption without appropriate justification.

2. Heating

The following heating systems can be used in high-rise buildings:

water two-pipe with horizontal distribution across floors or vertical;

air with heating and recirculation units within one room or combined with a mechanical supply ventilation system;

electrical according to the design assignment and upon receipt of technical specifications from the energy supply organization.

It is allowed to use underfloor (water or electric) heating to heat bathrooms, locker rooms, swimming pool areas, etc.

The parameters of the coolant in the heating systems of the corresponding zone should be taken according to SP 60.13330: no more than 95°C in systems with pipelines made of steel or copper pipes and no more than 90°C - from polymer pipes approved for use in construction.

Air-thermal regime of a high-rise building

Outdoor air parameters should be taken taking into account the following factors:

decrease in air temperature in altitude by 1 °C for every 100 m;

increased wind speed during the cold season;

the appearance of powerful convective flows on building facades irradiated by the sun;

placement of air intake devices in the high-rise part of the building.

When placing receiving devices for outside air on the southeast, south or southwest facades, the outside air temperature in the warm season should be taken 3-5 °C higher than the calculated one.

During the cold period of the year in residential, public, administrative and industrial premises (refrigeration units, elevator machine rooms, ventilation chambers, pump rooms, etc.), when they are not in use and during non-working hours, it is allowed to reduce the air temperature below the normalized one, but not less than:

16С - in residential premises;

12С - in public and administrative premises;

5С - in production premises.

By the beginning of working hours, the air temperature in these rooms must correspond to the standard.

At the entrance vestibules of high-rise buildings, as a rule, double airlocking of the hall or vestibule should be provided. It is recommended to use airtight devices of a circular or radius type as entrance doors.

Initially, the design of zone heating systems was carried out as for conventional multi-storey buildings. As a rule, two-pipe heating systems with vertical risers and lower distribution of supply and return lines running along the technical floor were used, which made it possible to turn on the heating system without waiting for the construction of all floors of the zone. Such heating systems were implemented, for example, in the residential complexes "Scarlet Sails", "Vorobyovy Gory", "Triumph Palace" (Moscow). Each riser is equipped with automatic balancing valves to ensure automatic distribution of the coolant along the risers, and each heating device is equipped with an automatic thermostat with increased hydraulic resistance to provide the resident with the opportunity to set the desired air temperature in the room and minimize the influence of the gravitational component of the circulation pressure and turning on/off thermostats on other heating devices connected to this riser.

Further, in order to avoid imbalance of the heating system associated with the unauthorized removal of thermostats in individual apartments, which has repeatedly occurred in practice, it was proposed to switch to a heating system with an overhead distribution of the supply line with a parallel movement of the coolant along the risers. This equalizes the pressure loss of the circulation rings through the heating devices, regardless of which floor they are located on, increases the hydraulic stability of the system, guarantees the removal of air from the system and facilitates the setting of thermostats.

However, subsequently, as a result of analyzing various solutions, the designers came to the conclusion that the best heating system, especially for buildings without technical floors, are systems with apartment-by-apartment horizontal wiring connected to vertical risers, usually running along the staircase, and made according to two-pipe scheme with lower routing of lines. For example, such a system was designed in the crowning part (9 floors of the third zone) of the Triumph Palace high-rise complex and in a 50-story building under construction without intermediate technical floors.

Apartment heating systems are equipped with a unit with a shut-off valve, regulating valves using balancing valves and drain valves, filters and a heat energy meter. This unit should be located outside the apartment on the staircase for unhindered access by the maintenance service. In apartments over 100 m2, the connection is made not through a loop perimeter laid around the apartment (since as the load increases, the diameter of the pipeline increases, and as a result, installation becomes more complicated and the cost increases due to the use of expensive large fittings), but through an intermediate apartment distribution cabinet, in which a comb is installed, and from it the coolant is directed through a radial scheme through pipelines of smaller diameter to the heating devices according to a two-pipe scheme.

Pipelines are used from heat-resistant polymeric materials, usually from cross-linked polyethylene PEX, the laying is carried out in floor preparation. The calculated parameters of the coolant, based on the technical conditions for such pipelines, are 90–70 (65) °C due to the fear that a further decrease in temperature leads to a significant increase in the heating surface of heating devices, which is not welcomed by investors due to the rising cost of the system. The experience of using metal-plastic pipes in the heating system of complexes was considered unsuccessful. During operation, as a result of aging, the adhesive layer is destroyed and the inner layer of the pipe “collapses,” as a result of which the flow area narrows and the heating system stops working normally.

The use of apartment-by-apartment horizontal heating systems compared to a system with vertical risers leads to a reduction in the length of the main pipelines (they are suitable only for the staircase riser, and not to the most distant riser in the corner room), a reduction in heat losses by pipelines, simplified floor-by-floor commissioning of the building and an increase in hydraulic stability of the system. The cost of installing an apartment-by-apartment system is not much different from standard ones with vertical risers, but the service life is longer due to the use of pipes made of heat-resistant polymer materials.

In apartment heating systems, heat energy metering can be carried out much easier and with absolute clarity for residents. We must agree with the opinion of the authors that although the installation of heat meters does not relate to energy-saving measures, however, payment for actually consumed thermal energy is a powerful incentive forcing residents to use it carefully. Naturally, this is achieved, first of all, by the mandatory use of thermostats on heating devices. Experience in their operation has shown that in order to avoid influencing the thermal conditions of adjacent apartments, the thermostat control algorithm should include a limitation on reducing the temperature in the room they serve to no lower than 15–16 °C, and heating devices should be selected with a power reserve of at least 15%.

These are the solutions for heat supply and heating systems of the tallest residential buildings built to date. They are clear, logical and do not fundamentally differ from the solutions used in the design of conventional multi-storey buildings less than 75 m in height, with the exception of the division of heating and water supply systems into zones. But within each zone, standard approaches to implementing these systems are retained. Greater attention is paid to installations for filling heating systems and maintaining pressure in them, as well as in circulation lines from different zones before connecting them to a common comb, automatic regulation of heat supply and distribution of coolant to implement comfortable and economical modes, redundant operation of equipment to ensure uninterrupted supply heat consumers.

When designing professional heating systems, it is necessary to take into account all factors - both external and internal. This is especially true for heat supply schemes for multi-apartment buildings. What is special about the heating system of a multi-storey building: pressure, diagrams, pipes. First you need to understand the specifics of its arrangement.

Features of heat supply of multi-storey buildings

Autonomous heating of a multi-storey building must perform one function - timely delivery of coolant to each consumer while maintaining its technical qualities (temperature and pressure). To do this, the building must have a single distribution unit with the ability to regulate. In autonomous systems it is combined with water heating devices - boilers.

The characteristic features of the heating system of a multi-storey building lie in its organization. It must consist of the following mandatory components:

Distribution node. With its help, hot water is supplied through the mains;
Pipelines. They are designed to transport coolant to individual rooms and areas of the house. Depending on the method of organization, there is a single-pipe or two-pipe heating system for a multi-story building;
Control and control equipment. Its function is to change the characteristics of the coolant depending on external and internal factors, as well as its qualitative and quantitative accounting.

In practice, the heating scheme of a residential multi-storey building consists of several documents, which, in addition to drawings, include a calculation part. It is compiled by special design bureaus and must comply with current regulatory requirements.

The heating system is an integral part of a multi-storey building. Its quality is checked upon delivery of the facility or during scheduled inspections. Responsibility for this lies with the management company.

Piping in a multi-storey building

For normal operation heating supply of a building, it is necessary to know its basic parameters. What is the pressure in the heating system of a multi-storey building, as well as temperature regime will be optimal? According to the standards, these characteristics must have the following values:

Pressure. For buildings up to 5 floors - 2-4 atm. If there are nine floors - 5-7 atm. The difference lies in the pressure of hot water to transport it to upper levels Houses;
Temperature. It can vary from +18°C to +22°C. This applies to residential premises only. On landings and non-residential rooms, a decrease to +15°C is allowed.

Having determined the optimal parameter values, you can begin to select the heating layout in multi-storey building.

It largely depends on the number of floors of the building, its area and the power of the entire system. The degree of thermal insulation of the house is also taken into account.

The pressure difference in the pipes on the 1st and 9th floors can be up to 10% of the standard value. This is a normal situation for a multi-story building.

Single-pipe heating distribution

This is one of economical options organizing heat supply in a building with relatively large area. For the first time, a single-pipe heating system for a multi-story building began to be used on a large scale for “Khrushchev” buildings. The principle of its operation is that there are several distribution risers to which consumers are connected.

The coolant is supplied through one pipe circuit. The absence of a return line greatly simplifies the installation of the system, while reducing the cost. However, at the same time Leningrad system heating a multi-storey building has a number of disadvantages:

Uneven heating of the room depending on the distance from the point of hot water intake (boiler or collector unit). Those. There may be options when a consumer connected earlier in the circuit will have hotter batteries than those next in the chain;
Problems with adjusting the degree of heating of radiators. To do this, you need to make a bypass on each radiator;
Complex balancing of a single-pipe heating system for a multi-storey building. It is carried out using thermostats and shut-off valves. In this case, system failure is possible even with a slight change in input parameters - temperature or pressure.

Currently, installing a single-pipe heating system in a new multi-story building is extremely rare. This is due to the difficulty individual accounting coolant in separate apartment. Thus, in residential buildings of the Khrushchev project, the number of distribution risers in one apartment can reach up to 5. Those. It is necessary to install an energy consumption meter on each of them.

A correctly drawn up estimate for heating a multi-storey building with a single-pipe system should include not only the costs of Maintenance, but also modernization of pipelines - replacement of individual components with more efficient ones.

Two-pipe heating distribution

To increase operating efficiency, it is best to install a two-pipe heating system in a multi-story building. It also consists of distribution risers, but after the coolant passes through the radiator, it enters the return pipe.

Its main difference is the presence of a second circuit that acts as a return line. It is necessary for collecting cooled water and transporting it to the boiler or to a heating station for further heating. During design and operation, it is necessary to take into account a number of features of the heating system of a multi-storey building of this type:

Possibility of adjusting the temperature level in individual apartments and throughout the highway as a whole. To do this, it is necessary to install mixing units;
To carry out repairs or maintenance work, you do not need to turn off the entire system, as in the Leningrad heating scheme for a multi-storey building. It is enough to use shut-off valves to shut off the flow into a separate heating circuit;
Low inertia. Even with a well-balanced single-pipe heating system in a multi-storey building, the consumer needs to wait 20-30 seconds for the hot water to reach the radiators through the pipelines.

What is the optimal pressure in the heating system of a multi-storey building? It all depends on its number of floors. It should ensure that the coolant rises to the required height. In some cases, it is more effective to install intermediate pumping stations to reduce the load on the entire system. In this case, the optimal pressure value should be from 3 to 5 atm.

Before purchasing radiators, you need to find out its characteristics from the heating scheme of a multi-storey residential building - pressure and temperature conditions. Based on this data, batteries are selected.

Heat supply of a multi-storey building

Heating distribution in a multi-storey building has important for system operating parameters. However, in addition to this, the characteristics of the heat supply should be taken into account. An important one is the method of supplying hot water - centralized or autonomous.

In overwhelming cases, a connection is made to the central heating system. This allows you to reduce the current costs in the estimate for heating a multi-storey building. But in practice the level of quality of such services remains extremely low. Therefore, if there is a choice, preference is given to autonomous heating of a multi-storey building.

Autonomous heating of a multi-storey building

In modern multi-storey residential buildings it is possible to organize independent system heat supply. It can be of two types - apartment-based or communal. In the first case, the autonomous heating system of a multi-storey building is carried out in each apartment separately. To do this, make independent piping and install a boiler (most often a gas one). A common house installation involves the installation of a boiler room, which has special requirements.

The principle of its organization is no different from a similar scheme for private country house. However, there are a number important points that need to be taken into account:

Installation of several heating boilers. One or more of them must perform a duplicate function. If one boiler fails, another must replace it;
Installation of a two-pipe heating system of a multi-storey building, as the most efficient;
Drawing up a schedule for scheduled repairs and maintenance work. This is especially true for heating heating equipment and safety groups.

Considering the features heating circuit For a specific multi-storey building, it is necessary to organize an apartment-by-apartment heat metering system. To do this, energy meters must be installed on each incoming pipe from the central riser. That is why the Leningrad heating system of a multi-storey building is not suitable for reducing operating costs.

Centralized heating of a multi-storey building

How the heating distribution can change in apartment building when connecting it to the central heating supply? The main element of this system is the elevator unit, which performs the functions of normalizing coolant parameters to acceptable values.

The total length of the central heating mains is quite large. Therefore, at the heating point, such coolant parameters are created so that heat losses are minimal. To do this, the pressure is increased to 20 atm, which leads to an increase in the temperature of hot water to +120°C. However, given the characteristics of the heating system in an apartment building, supplying hot water with such characteristics to consumers is not permitted. To normalize the parameters of the coolant, an elevator unit is installed.

It can be calculated for both a two-pipe and a single-pipe heating system in a multi-storey building. Its main functions are:

Reducing pressure using an elevator. A special cone valve regulates the volume of coolant flow into the distribution system;
Reducing the temperature level to +90-85°C. A mixing unit for hot and cooled water is designed for this purpose;
Filtration of coolant and reduction of oxygen content.

In addition, the elevator unit performs the main balancing of the single-pipe heating system in the house. For this purpose, it is equipped with shut-off and control valves, which automatically or semi-automatically regulate pressure and temperature.

Description:

The buildings discussed in the book can be classified as high-rise buildings. We hope that in the future there will be a book about domestic experience in designing engineering equipment for super-tall buildings, figuratively called skyscrapers.

Heat and water supply and heating of high-rise residential buildings

Towards the publication of the book

V. I. Livchak, Vice-President of NP "ABOK", Head of the Energy Efficiency of Construction Department of the Moscow State Expertise

In Moscow, half a century after the construction of seven “Stalinist” high-rise buildings, the construction of high-rise buildings has resumed. Nowadays buildings higher than 40 floors have been built: in 2003 - “Edelweiss” on Davydkovskaya Street, vl. 3 (height 176 m, 43 floors), “Scarlet Sails” building 4 (179 m, 48 floors) on Aviatsionnaya street, ow. 77–79; in 2004 - “Vorobyovy Gory” (188 m, 49 floors) on Mosfilmovskaya street, vl. 4–6, “Triumph Palace” - the tallest residential building in Europe (225 m, 59 floors, with a spire - 264 m), Chapaevsky lane, vl. 2.

Several dozen buildings with a height of 30–50 floors are planned for construction under the city investment program “New Moscow Ring”. In the Moscow City business center, a number of skyscrapers with a height of more than 300 m are being built, and the apotheosis of all is supposed to be the construction of the Russia Tower, 600 m high, designed by the English architect Norman Foster, the design of which began in 2006.

The project of the Edelweiss residential building was completed by TsNIIEPdzhilishcha, the engineering part of the remaining listed high-rise residential buildings built by the DON-Stroy company was the fruit of the creativity of the design and production company Alexander Kolubkov, led by A. N. Kolubkov and bearing his name. It is also interesting that DON-Stroy itself operates the houses it constructs, and therefore the solutions used are confirmed by the practice of their work.

The experience gained in the design of these buildings and their operation was the basis for the book “Engineering Equipment of High-Rise Buildings”, published by AVOK-PRESS in 2007 under general edition prof. MArchI M. M. Brodach.

In our opinion, all buildings can be divided into 5 categories based on height:

Up to five floors where installation of elevators is not required - low-rise buildings;

Up to 75 m (25 floors), within which vertical zoning into fire compartments is not required - multi-storey buildings;

76–150 m – high-rise buildings;

151–300 m – high-rise buildings;

Over 300 m – super-tall buildings.

The gradation multiple of 150 m is due to a change in the calculated temperature of the outside air for designing heating and ventilation - every 150 m it decreases by 1 °C.

Features of the design of buildings above 75 m are related to the fact that they must be divided vertically into sealed fire compartments (zones), the boundaries of which are enclosing structures that provide the required fire resistance limits to localize a possible fire and prevent it from spreading to adjacent compartments. The height of the zones should be 50–75 m, and it is not necessary to separate vertical fire compartments with technical floors, as is customary in warm countries, where technical floors do not have walls and are used to collect people in case of fire and their subsequent evacuation. In countries with harsh climates, the need for technical floors is determined by the requirements for the placement of engineering equipment. When installing it in the basement, only part of the floor located on the border of the fire compartments can be used to accommodate smoke protection fans, the rest for work spaces. With a cascade scheme for connecting heat exchangers, as a rule, they, together with pumping groups, are placed on technical floors, where they require more space, and occupy the entire floor, and in super-tall buildings sometimes two floors.

Below we will give an analysis of design solutions for heat and water supply and heating of the listed residential buildings. And this is only part of the topic to which the book under review is devoted; beyond the scope of this article remains the analysis of advanced solutions implemented in a number of foreign high-rise buildings, and the features of the influence of the external climate, experience in designing ventilation and air conditioning systems for residential and public buildings, fire safety systems, drainage and waste disposal, automation and dispatching, also given in the book “Engineering equipment of high-rise buildings”.

Heat supply

A feature of the design of heat and water supply systems is that all pumping and heat exchange equipment of the high-rise residential buildings under consideration is located at ground level or minus the first floor. This is due to the danger of placing superheated water pipelines on residential floors, uncertainty about the adequacy of protection from noise and vibration of adjacent residential premises during operation of pumping equipment, and the desire to preserve scarce space to accommodate a larger number of apartments.

This solution is possible thanks to the use of high-pressure pipelines, heat exchangers, pumps, shut-off and control equipment that can withstand operating pressures of up to 25 atm. Therefore, when piping heat exchangers from the local water side, they use butterfly valves with collar flanges, pumps with a U-shaped element, direct-acting “upstream” pressure regulators installed on the make-up pipeline, and solenoid valves designed for a pressure of 25 atm. in the heating system filling station.

Another feature of the heat supply of implemented high-rise residential buildings is that in all cases the source of heat supply is city heating networks. Connection to them is made through a central heating substation, which occupies a fairly large area, for example, in the Vorobyovy Gory complex it occupies 1,200 m 2 with a room height of 6 m (estimated power 34 MW).

The central heating system includes heat exchangers with circulation pumps for heating systems in different zones, heat supply systems for ventilation and air conditioning heaters, hot water supply systems, pumping stations for filling heating systems and pressure maintenance systems with expansion tanks and auto-regulation equipment, emergency electric storage water heaters for hot water supply. Equipment and pipelines are located vertically so that they are easily accessible during operation. A central passage with a width of at least 1.7 m passes through all central heating centers to allow the movement of special loaders, allowing the removal of heavy equipment when replacing it (Fig. 1).

Picture 1.

This decision is also due to the fact that high-rise complexes, as a rule, are multifunctional in purpose with a developed stylobate and underground part, on which several buildings can be located. Therefore, in the Vorobyovy Gory complex, which includes 3 high-rise residential buildings with 43–48 floors and 4 buildings with a height of 17–25 floors, united by a five-level stylobate part, technical collectors with numerous pipelines depart from this single central heating point, and to reduce them in technical In the zone of high-rise buildings, booster water supply pumping stations were located, which pump cold and hot water into each zone of high-rise buildings.

Another solution is also possible - the central heating station serves to introduce urban heating networks to the facility, place a pressure differential regulator “after itself”, a heat metering unit and, if necessary, a cogeneration installation and can be combined with one of the individual local heating points (ITP), serving to connect local heat consumption systems close in location to a given heating point. From this central heating station, superheated water is supplied through two pipes, and not through several from the comb, as in the previous case, to local ITPs located in other parts of the complex, including on the upper floors, according to the principle of proximity to the thermal load. With this solution, there is no need to connect the internal heat supply system to the supply air heaters according to an independent circuit through a heat exchanger. The heater itself is a heat exchanger and is connected directly to the superheated water pipelines with pump mixing to improve the quality of load control and increase the reliability of the heater protection from freezing.

One of the solutions for reserving centralized heat and power supply to high-rise buildings may be the construction of autonomous mini-CHPs based on gas turbine (GTU) or gas piston (GPU) units that simultaneously generate both types of energy. Modern means of protection against noise and vibration make it possible to place them directly in the building, including on the upper floors. As a rule, the power of these installations does not exceed 30–40% of the maximum required power of the facility and in normal mode these installations operate, complementing the centralized energy supply systems. With greater power of cogeneration plants, problems arise in transferring excess energy carriers to the network.

The book provides an algorithm for calculating and selecting mini-CHP for power supply to an object in autonomous mode and an analysis of optimization of the choice of mini-CHP using the example of a specific project. If there is a shortage of only thermal energy for the object under consideration, an autonomous heat supply source (AHS) in the form of a boiler room with hot water boilers can be accepted as a source of heat supply. Attached, located on the roof or protruding parts of the building, or free-standing boiler rooms designed in accordance with SP 41-104-2000 can be used. The possibility and location of AIT should be linked to the entire complex of its impact on the environment, including on a residential high-rise building.

Heating

Initially, the design of zone heating systems was carried out as for conventional multi-storey buildings. As a rule, two-pipe heating systems with vertical risers and lower distribution of supply and return lines running along the technical floor were used, which made it possible to turn on the heating system without waiting for the construction of all floors of the zone. Such heating systems were implemented in the residential complexes “Scarlet Sails”, “Vorobyovy Gory”, “Triumph Palace”. Each riser is equipped with automatic balancing valves to ensure automatic distribution of the coolant along the risers, and each heating device is equipped with an automatic thermostat with increased hydraulic resistance to provide the resident with the opportunity to set the desired air temperature in the room and minimize the influence of the gravitational component of the circulation pressure and turning on/off thermostats on other heating devices connected to this riser.

Further, in order to avoid imbalance of the heating system associated with the unauthorized removal of thermostats in individual apartments, which has repeatedly occurred in practice, it was proposed to switch to a heating system with an overhead distribution of the supply line with a parallel movement of the coolant along the risers. This equalizes the pressure loss of the circulation rings through the heating devices, regardless of which floor they are located on, increases the hydraulic stability of the system, guarantees the removal of air from the system and facilitates the setting of thermostats.

However, subsequently, as a result of analyzing various solutions, the designers came to the conclusion that the best heating system, especially for buildings without technical floors, are systems with apartment-by-apartment horizontal wiring connected to vertical risers, usually running along the staircase, and made according to two-pipe scheme with lower routing of lines. Such a system is designed in the crowning part (9 floors of the third zone) of the Triumph Palace high-rise complex and in a 50-story building under construction without intermediate technical floors on the street. Pyreva, 2.

Apartment heating systems are equipped with a unit with a shut-off valve, regulating valves using balancing valves and drain valves, filters and a heat energy meter. This unit should be located outside the apartment on the staircase for unhindered access by the maintenance service. In apartments over 100 m2, the connection is made not with a loop perimeter laid around the apartment (since with increasing load the diameter of the pipeline increases, and as a result, installation becomes more complicated and the cost increases due to the use of expensive large fittings), but through an intermediate apartment distribution cabinet, in in which the comb is installed, and from it the coolant is directed through a radial scheme through pipelines of smaller diameter to the heating devices according to a two-pipe scheme.

Pipelines are used from heat-resistant polymeric materials, as a rule, PEX cross-linked polyethylene (the rationale for its use is given in the book), laying is carried out in floor preparation. The calculated parameters of the coolant, based on the technical conditions for such pipelines, are 90–70 (65) °C for fear that a further decrease in temperature leads to a significant increase in the heating surface of heating devices, which is not welcomed by investors due to the increase in the cost of the system. The experience of using metal-plastic pipes in the heating system of the Triumph Palace complex was considered unsuccessful. During operation, as a result of aging, the adhesive layer is destroyed and the inner layer of the pipe “collapses”, as a result of which the flow area narrows and the heating system stops working normally.

The authors of the book believe that for apartment wiring, the optimal solution is to use automatic balancing valves ASV-P (PV) on the return pipeline and shut-off and measuring valves ASV-M (ASV-1) on the supply pipeline. The use of this pair of valves makes it possible not only to compensate for the influence of the gravitational component, but also to limit the flow rate for each apartment in accordance with the parameters. Valves are usually selected according to the diameter of the pipelines and are set to maintain a pressure drop of 10 kPa. This valve setting value is selected based on the required pressure loss on radiator thermostats to ensure their optimal operation. The limitation of flow per apartment is set by the settings on the ASV-1 valves, and it is taken into account that in this case the pressure loss on these valves must be included in the pressure difference maintained by the ASV-PV regulator.

Water supply

To increase the reliability of water supply in buildings up to 250 m, at least two inputs from independent water supply systems (separate lines of the external ring water supply network) are provided; at higher heights, each input is laid in two lines, each of which must be designed to pass at least 50% of the calculated consumption.

In order to increase reliability and ensure uninterrupted operation of hot water supply in all high-rise residential buildings In addition to high-speed water-water heaters, they provide for the installation of capacitive electric water heaters that turn on during shutdowns of the heating network for scheduled maintenance or accidents. The volume of these backup water heaters is selected based on the hour and a half peak hot water consumption. The power of the heating element is set so that the heating time for a given volume of water is 8 hours - this is the interval between peak morning and evening water intakes.

As a rule, there are many backup electric water heaters (there are facilities where their number reaches 13 units), and for the stability of their operation, the water heaters should be switched on according to the scheme with the passing movement of water. If the water heater is the first to connect hot water, it should be the last to supply heated water. The operating pressure of electric water heaters does not exceed 7 atm. This determines the height of the water supply system zone. Therefore, it is not necessary that the number of zones in water supply systems coincide with heating. So, in a 50-story residential building on the street. Pyryev provides 3 vertical zones for the heating system and 4 for hot and cold water supply (Fig. 2). The latest systems have the same number of zones to allow for redundancy between them.

Figure 2 ()

Zoning of engineering systems

Another feature of the hot water supply system of the listed high-rise buildings is that, regardless of the number of zones, a single heat exchanger is installed for the entire system, and then hot water is pumped into the corresponding zone by separate booster pumping stations. Also, for cold water, each zone has its own booster pumping stations nearby, which increases the reliability of the water supply system, allowing water supply through hot water pipelines in emergency situations.

The connection of circulation pipelines of different zones to a common comb occurs through a unit that includes, in addition to shut-off valves and a check valve, a downstream pressure regulator and a flow regulator. This scheme was adopted after much trial and error. Electrically controlled control valves were installed first. During operation, it turned out that their response speed is not enough for normal operation. It was necessary to find equipment that could more quickly respond to changes in pressure in the circulation pipeline. As a result, direct acting pressure regulators were selected. They were originally supplied without flow regulators, but since circulation pumps contribute to airing, these pressure regulators began to work like chokes with unacceptable noise. To eliminate this defect, they tried to adjust the system more carefully, but then they installed flow regulators, after which the described effect disappeared.

To prevent changes in pressure in the city water supply from affecting the stability of pressure maintenance at pumping stations, a “downstream” pressure regulator is installed at the water supply inlet. If before the installation of this regulator the pressure spread was 0.6–0.9 atm, then after installation it stabilized at the level of 0.2–0.4 atm. The hot water supply inlet (after the heat exchangers, before the pumping station of each zone) also has its own downstream pressure regulators, which eliminate false alarms check valves and turning on backup pumps without special need.

The water supply system, as a rule, is organized with horizontal apartment distribution. This solution has been successfully implemented in the high-rise residential complexes “Vorobyovy Gory”, “Triumph Palace” and on the street. Pyryeva. In this case, the risers of the water supply system are laid in the staircase and elevator hall, from where hot and cold water pipelines are introduced into the apartment. The system is equipped with cold and hot water meters, which, together with filters and pressure regulators, are installed in distribution cabinets in the staircase and elevator hall. To avoid the flow of water (from cold to hot mains and vice versa), resulting from improper operation of plumbing equipment, check valves are installed at the entrances to apartments on the cold and hot water supply pipelines.

The distribution of pipelines from risers to apartments and in apartments is carried out from cross-linked polyethylene pipes (PEX pipes). In apartments, it is advisable to use collector wiring, when water is supplied to each water tap from the collector through a separate pipe, this minimizes the influence of neighboring devices on each other (when one mixer is turned on, the temperature of the spout on the other changes). The risers are laid from steel pipes, and just like in a heating system, hot water supply risers are equipped with compensators and fixed supports. The calculated circulation is set to 40% of the calculated water withdrawal using control and balancing valves.

When installing a horizontal hot water supply system, you can avoid installing heated towel rails. Operating experience has shown that even in buildings equipped with heated towel rails, up to 70% of apartment owners do not use them. They either leave the bathroom without heated towel rails at all, or use electric heated towel rails. The use of electric heated towel rails, from the point of view of the apartment owner, is more convenient, since it turns on only when necessary.

These are the solutions for heat and water supply and heating systems for the tallest residential buildings built to date in Moscow. They are clear, logical and do not fundamentally differ from the solutions used in the design of conventional multi-storey buildings less than 75 m in height, with the exception of the division of heating and water supply systems into zones. But within each zone, standard approaches to implementing these systems are retained. Greater attention is paid to installations for filling heating systems and maintaining pressure in them and on each floor of water supply systems, as well as in circulation lines from different zones before connecting them to a common comb, automatic control of heat supply and coolant distribution to implement comfortable and economical modes, redundancy operation of equipment to ensure uninterrupted supply of heat and water to consumers.

Distinctive feature is used for the purpose of uninterrupted supply hot water emergency capacitive electric water heaters for an hour and a half supply of water. But it appears that their capabilities are not being fully utilized. In addition to turning them on during an accident or scheduled preventive maintenance of heating networks, they could be tied in such a way that their capacity is used to relieve peak heat loads on the heating system.

This ingenious scheme, proposed by the progenitor of hot water supply technology A.V. Khludov, includes a water heater, a storage tank and a pump that performs the function of charging the tank with hot water (Fig. 3). When the battery is charged, cold water flows in parallel streams into the water heater and into the storage tank, displacing it from bottom to top hot water from the battery to the consumer system. Thus, with large water consumption, the consumer receives hot water from the water heater and battery into his system. When the water intake decreases, the pump squeezes out excess water heated in the water heater into the storage tank, thereby displacing cold water from the bottom of the battery into the water heater, i.e. the battery is charged. This allows you to equalize the load on the water heater and reduce its heating surface.

When designing large-scale heating systems (in particular, calculating the adjustment of the heating system of an apartment building and its full functioning), especially close attention is paid to the external and internal factors of equipment operation. Several heating schemes for central heating have been developed and are successfully used in practice, differing from each other in structure, working fluid parameters and pipe routing patterns in apartment buildings.

What types of heating systems are there for an apartment building?

Depending on the installation of the heat generator or the location of the boiler room:

Heating schemes depending on the parameters of the working fluid:

Based on the piping diagram:

Functioning of the heating system of an apartment building

Autonomous heating systems of a multi-storey residential building perform one function - timely transportation of heated coolant and its adjustment for each consumer. To ensure the possibility of general control of the circuit, a single distribution unit with elements for adjusting the parameters of the coolant, combined with a heat generator, is installed in the house.

An autonomous heating system for a multi-storey building necessarily includes the following units and components:

The pipeline route through which the working fluid is delivered to apartments and premises. As already mentioned, the pipe layout in multi-story buildings can be single- or double-circuit;
KPiA - control instruments and equipment that reflects the parameters of the coolant, regulates its characteristics and takes into account all its changing properties (flow, pressure, inflow rate, chemical composition);
A distribution unit that distributes heated coolant through pipe lines.

A practical heating scheme for a residential multi-storey building includes a set of documentation: design, drawings, calculations. All documentation for heating in an apartment building is drawn up by the responsible executive services (design bureaus) in strict accordance with GOST and SNiP. Responsibility for ensuring that the centralized system central heating will be operated correctly, is entrusted to management company, as well as its repair or complete replacement heating systems in an apartment building.

How does the heating system work in an apartment building?

The normal operation of the heating of an apartment building depends on compliance with the basic parameters of the equipment and coolant - pressure, temperature, wiring diagram. According to accepted standards, the main parameters must be observed within the following limits:

For an apartment building with a height of no more than 5 floors, the pressure in the pipes should not exceed 2-4.0 Atm;
For an apartment building with a height of 9 floors, the pressure in the pipes should not exceed 5-7 Atm;
The temperature range for all heating schemes operating in residential premises is +18 0 C/+22 0 C. The temperature in radiators on staircases and in technical rooms is -+15 0 C.

The choice of piping in a five-story or multi-story building depends on the number of floors, the total area of the building, and the thermal output of the heating system, taking into account the quality or availability of thermal insulation of all surfaces. In this case, the difference in pressure between the first and ninth floors should not be more than 10%.

Single-pipe wiring

Most economical option pipe distribution - according to a single-circuit scheme. A single-pipe circuit works more efficiently in low-rise buildings and with a small heating area. As a water (rather than steam) heating system, single-pipe wiring began to be used from the early 50s of the last century, in the so-called “Khrushchev buildings”. The coolant in such a distribution flows through several risers to which apartments are connected, while the entrance for all risers is one, which makes installation of the route simple and quick, but uneconomical due to heat losses at the end of the circuit.

Since the return line is physically absent, and its role is played by the working fluid supply pipe, this gives rise to a number of negative aspects in the operation of the system:

The room is heated unevenly, and the temperature in each individual room depends on the distance of the radiator to the point of intake of the working fluid. With this dependence, the temperature on distant batteries will always be lower;
Manual or automatic temperature control on heating devices is impossible, but bypasses can be installed in the Leningradka circuit, which allows you to connect or disconnect additional radiators;
It is difficult to balance a single-pipe heating scheme, since this is only possible when shut-off valves and thermal valves are included in the circuit, which, if the coolant parameters change, can cause a failure of the entire heating system of a three-story or higher building.

In new buildings single-pipe scheme have not been implemented for a long time, since it is almost impossible to effectively monitor and account for coolant flow for each apartment. The difficulty lies precisely in the fact that for each apartment in a Khrushchev building there can be up to 5-6 risers, which means that you need to install the same number of water meters or hot water meters.

A correctly drawn up estimate for heating a multi-storey building with a single-pipe system should include not only maintenance costs, but also the modernization of pipelines - the replacement of individual components with more efficient ones.

Two-pipe wiring

This heating scheme is more efficient, since in it the cooled working fluid is taken through a separate pipe - the return pipe. The nominal diameter of the return coolant supply pipes is chosen to be the same as for the supply heating main.

The double-circuit heating system is designed in such a way that the water that has given off heat to the apartment is supplied back to the boiler through a separate pipe, which means it does not mix with the supply and does not take away the temperature from the coolant delivered to the radiators. In the boiler, the cooled working fluid is heated again and sent to the supply pipe of the system. When drawing up a project and during operation of heating, the following features should be taken into account:

You can regulate the temperature and pressure in the heating main in any individual apartment, or in a common heating main. To adjust the system parameters, mixing units are cut into the pipe;
When carrying out repair or maintenance work, the system does not need to be turned off - the necessary areas are cut off by shut-off valves, and the faulty circuit is repaired, while the remaining areas operate and move heat throughout the house. This is both the principle of operation and the advantage two-pipe system in front of the others.

The pressure parameters in the heating pipes in an apartment building depend on the number of floors, but are in the range of 3-5 Atm, which should ensure the delivery of heated water to all floors without exception. In high-rise buildings to raise the coolant to last floors intermediate pumping stations may be used. Radiators for any heating systems are selected according to design calculations, and must withstand the required pressure and maintain the specified temperature.

Heating system

The layout of heating pipes in a multi-storey building plays a big role in maintaining the specified parameters of the equipment and working fluid. Thus, the upper distribution of the heating system is more often used in low-rise buildings, the lower - in high-rise buildings. The method of coolant delivery - centralized or autonomous - can also affect reliable operation heating in the house.

In most cases, a connection is made to the central heating system. This allows you to reduce the current costs in the estimate for heating a multi-storey building. But in practice the level of quality of such services remains extremely low. Therefore, if there is a choice, preference is given to autonomous heating of a multi-storey building.

Modern new buildings are connected to mini-boiler houses or to centralized heating, and these schemes work so efficiently that it makes no sense to change the connection method to autonomous or another (communal or apartment-by-house). But stand-alone circuit gives preference to apartment-by-apartment or general-house heat distribution. When installing heating in each individual apartment, autonomous (independent) pipe distribution is carried out, a separate boiler is installed in the apartment, control and metering devices are also installed for each apartment separately.

When organizing a common house wiring, it is necessary to build or install a common boiler room with its own specific requirements:

Several boilers must be installed - gas or electric, so that in case of an accident it is possible to duplicate the operation of the system;
Only a double-circuit pipeline route is being carried out, the plan of which is drawn up during the design process. Such a system is regulated for each apartment separately, since the settings can be individual;
A schedule of planned preventative and repair activities is required.

In a communal heating system, heat consumption is monitored and metered apartment by apartment. In practice, this means that a meter is installed on each coolant supply pipe from the main riser.

Centralized heating for an apartment building

If you connect the pipes to the central heating supply, what difference will there be in the wiring diagram? The main working unit of the heat supply circuit is the elevator, which stabilizes the liquid parameters within the specified values. This is necessary due to the long length of heating mains in which heat is lost. The elevator unit normalizes temperature and pressure: for this, in the heating station, the water pressure is increased to 20 Atm, which automatically increases the temperature of the coolant to +120 0 C. But, since such characteristics of the liquid medium for pipes are unacceptable, the elevator normalizes them to acceptable values.

The heating point (elevator unit) operates both in a dual-circuit heating circuit and in single pipe system heating of an apartment high-rise building. Functions that it will perform with this connection: Reduce working pressure liquids using an elevator. The cone-shaped valve changes the flow of fluid into the distribution system.

Conclusion

When drawing up a heating project, do not forget that the estimate for installation and connection of centralized heating to an apartment building differs from the costs of organizing autonomous system to a lesser extent.