Dust collection units. Ventilation dust collection devices UVP for woodworking Dust collection systems for woodworking

Dust collection equipment is widely used in all industries National economy, including at food industry enterprises, to remove dust from ventilation and process emissions into the atmosphere. It is characterized by a wide variety of operating principles and design features. Depending on the method of separating dust from the air flow, equipment for collecting dust is distinguished between dry and wet method. Equipment that collects dust using the dry method is divided into four groups: gravitational, inertial, filtration and electrical. Wet dust collection equipment is classified into three groups: inertial, filtration and electric. Each of these groups includes different kinds equipment.

The main characteristics of dust collection equipment include the following: degree of air purification from dust (cleaning efficiency), productivity, hydraulic resistance, power consumption, cleaning cost, etc.

Cleaning efficiency characterized by the ratio of the mass of dust captured in the apparatus to the mass of dust entering the apparatus, and is expressed as a percentage or in fractions of a unit.

However, the calculation of cleaning efficiency (η) is carried out not by the mass of dust, but by the dust concentrations in the air before and after cleaning (C in and C out, mg/m 3), respectively:

With multi-stage cleaning used to more completely remove dust from the air, the total efficiency is determined by the formula:

Where η 1 , η 2 …η n – cleaning efficiency of each device (in fractions of a unit).

Cleaning efficiency is the most important characteristic of a dust separator. They are guided by it when choosing dust collection equipment in accordance with the permissible residual dust content in purified air.

Equipment performance is characterized by the amount of air that is purified in one hour. Hydraulic resistance is also important, since the required fan pressure depends on its value, and therefore the energy consumption, which for single-stage cleaning ranges from 0.035 to 1 kWh per 1000 m 3 of air.

Rice. 20 Cyclone

When choosing a dust separator, in addition to cleaning efficiency, dust dispersion, physical and chemical properties, explosion hazard, hygroscopicity, tendency to coagulate, etc. are also taken into account, as well as the value of dust, the need for its preservation and use.

Of the variety of designs of dust collectors, they are most widely used at food industry enterprises. cyclones and bag filters.

Cyclone devices belong to the group of inertial equipment in which dust is deposited from the air flow under the influence of centrifugal force.

Cyclones They are widely used for cleaning ventilation and process emissions from dust, which is explained by the simplicity of the device, operational reliability, and relatively low capital and operating costs.

Cyclone(Fig. 20) consists of cylindrical and conical parts. Dusty air enters the cyclone body 1 through pipe 2 tangentially to the inner surface of the body, usually at a speed of at least 20 m/s, and then moves in a spiral in the annular space between the body and the exhaust pipe 3. Under the influence of centrifugal force arising from the rotational movement of the flow , dust particles are thrown towards the walls of the cyclone and fall into the lower part of the apparatus, falling into hopper 4. The air flow, continuing its movement, enters the exhaust pipe and leaves the cyclone.

The magnitude of the centrifugal force Р c acting on a dust particle in a cyclone is described by the following equation:

Where V– speed of dust-air flow in the cyclone, m/s;

R– distance from the cyclone axis to the particle, m;

m– particle mass, kg.

From this formula it follows that the cleaning efficiency depends on the diameter of the cyclone, increasing as it decreases. Therefore, for significant volumes of air to be purified, it is more expedient, instead of installing one large-diameter cyclone, to use a group installation of smaller-diameter cyclones, structurally combined into one housing and having a common inlet and outlet of the dust-air mixture.

Cyclones effectively capture dust particles larger than 10 microns. Small fractions are carried away by the air flow, therefore, to capture fine dust particles, two- or three-stage cleaning is used, installing bag filters or wet dust collectors after the cyclones.

A large number of different types of cyclones are used in industry, which differ in shape, method of supplying air to the cyclone, productivity, cleaning efficiency, etc.

In the food industry, cyclones are used: NIIOGAZ, BC, UTs, OTI, SIOT, TsOL, VTSNIIOT, RISI, etc.

NIIOGAZ cyclones (TsN-11 and TsN-15) are approved as unified cyclone-type dust collectors. The numbers 11 and 15 correspond to the angle at which the air supply pipe is connected to the cyclone body. Cyclones TsN-11 and TsN-15 are used in the starch and tea industries, grain processing plants, sunflower seed processing plants, etc. In addition, cyclones of this type are used to collect dry dust from aspiration systems, ash from flue gases boiler houses operating on solid fuels, dust from dryers, etc. Depending on the required performance, they are installed singly or arranged in groups of two, four, six or eight cyclones. Such cyclones are called battery cyclones and are designated as BC, and when installing a sluice gate - BTsSh (4BTs, 8BTsSh, etc.). The cleaning efficiency of battery cyclones reaches 97-98% for dust with a particle size of more than 10 microns.

Cyclones UC with a case diameter of up to 850 mm, they are used in starch and fat-and-oil industries for single and battery installations. They differ from CN cyclones by their developed conical part. The cyclone UC is equipped with a spiral-flat inlet scroll, which increases the cleaning efficiency, which reaches 99%.

Cyclones TsOL used to purify air mainly from grain dust. The device is characterized by an elongated cylindrical part and significant depth of the exhaust pipe. A device is installed in the conical part of the device to reduce air leakage. The entry speed of the dust-air flow into the cyclone is at least 15-18 m/s. The productivity of cyclones is from 1000 to 18000 m 3 /h, the cleaning efficiency in capturing coarse dust, typical of elevators, is 90-95%.

Cyclones CIOT completely devoid of a cylindrical part, while the inlet pipe has a triangular cross-section. Cyclones are designed to clean ventilation emissions from dry, non-stick and non-fibrous dust. They can be used to capture lime dust at sugar and starch factories and a number of other enterprises. The cleaning efficiency of CIOT cyclones is 97-98%.

Cyclones RISI are designed to collect food production dusts that have specific properties - fibrousness, adhesiveness, hygroscopicity, etc. Among these cyclones, cyclones with coagulator cone, adjustable cyclones RC and RCP, cyclone with internal recirculation TsVR and etc.

Cyclone with coagulator cone allows you to solve the problem of cleaning emissions from fibrous dust. It is used in oil and fat enterprises to collect dust generated during the processing of sunflower and cotton seeds, to collect meal dust, etc. The cyclone differs from other cyclones with a reverse cone by the presence of an additional element - a coagulator cone. Thus, the conical part of the cyclone consists of two cones connected by the bases. In the coagulator cone, as a result of increasing the flow rate, fibrous dust particles coagulate, forming stable aggregates, while fine dust is captured by large particles, as a result of which the cleaning efficiency increases. From the coagulator cone, the dusty flow passes into reverse cone. The dust separated from the flow enters the bunker through the sluice gate.

The efficiency of the cyclone is more than 99%. 11 numbers of cyclones have been developed for productivity from 200 to 9000 m 3 /h.

Adjustable cyclone RC has a reverse cone equipped with a spiral-screw apparatus in which a control device is located. The cyclone is recommended for collecting dust from high humidity and oiliness, prone to sticking. In a cyclone of this design, dust coagulates, which prevents the removal of large particles with windage. The inner surface of the cyclone is periodically cleaned of adhering dust using a guide vane.

10 numbers of cyclone RC have been developed with a capacity from 250 to 4900 m 3 /h.

Cyclones with internal recirculation (ICR) designed to capture soybean dust and other types of dry, non-stick fine dust. The TsVR cyclone (Fig. 21) differs from the TsN-15 cyclone, on the basis of which it was developed, in that in the exhaust pipe 1 there is a slotted hole 2 and a helical guide tape 3. Through the slotted hole, part of the flow passing through the exhaust pipe is directed into cyclone body 4 for repeated cleaning. A helical guide tape located on the inner surface of the exhaust pipe is designed to intensify the process of movement of dust particles to the slot hole. Thanks to internal air flow recirculation, cleaning efficiency increases, which is 98-99%. 9 numbers of cyclone TsVR have been developed for productivity from 900 to 4500 m 3 /h.

Rice. 21 Cyclone TsVR

For fine cleaning of ventilation emissions from dust and gaseous impurities, they are used filtration dust collectors.

Dust collection in filtration cleaning devices is caused by the action of inertial, gravitational and electrostatic forces. By appropriate selection of filter material and air purification mode, it is possible to achieve the required degree of purification in filtration dust collectors in almost all necessary cases. Depending on the material of the filter layer, filtration dust collectors are divided into fabric and granular.

To purify dust emissions, the most widely used at food industry enterprises are fabric filters, in which fabrics made from natural fibers - cotton and wool - are used as filter materials; fabrics made of synthetic fibers - nitron, lavsan, polypropylene, etc., as well as fiberglass. When dusty air passes through the fabric, dust particles are trapped between the threads and the pile, while the pile should be facing towards the dusty air flow.

The following requirements are imposed on filter fabrics: high cleaning efficiency, sufficient air load (filtration speed), good dust holding capacity, regeneration ability, mechanical strength and abrasion resistance, low hygroscopicity, etc. In addition, additional requirements may be imposed, for example resistance to certain chemicals, high temperatures and etc.

The most common of fabric filters are bag filters type FV(Fig. 22), which are used to clean large volumes of air with a significant concentration of dust. They provide fine cleaning from particles with a size of 1 micron or less. Along with cyclones, bag fabric filters are the main dust collection equipment in the food industry. They are used in bakery, sugar, starch, grain processing, oil and fat and other enterprises. The operation of bag filters is characterized by cyclicity - every 3.5 minutes. regeneration of the hose section is provided for 30 seconds. Regeneration is carried out by shaking and back-blowing the hoses and is carried out section by section. As a result of this treatment, dust deposited on the inner surface of the fabric falls into a hopper, from which it is removed by a screw.

Rice. 22 Bag filter FV:

1 – sleeves; 2 – filter housing; 3 – inlet pipe; 4 – device for hose regeneration; 5 – pipe for removing purified air

There are four standard sizes of bag filters: FV-30; FV-40; FV-60; FV-90, where the numbers indicate the surface area of ​​the filter fabric in m2. The filter consists of 2-6 sections, each of which has from 36 to 108 hoses with a diameter of 120 to 300 mm and a length of 2.5 to 5 m.

A significant disadvantage of bag filters is the oiling of the fabric, the formation of a crust during condensation of water vapor, as a result of which the hydraulic resistance sharply increases. Therefore, when cleaning heated air, it is necessary to provide thermal insulation of the filter.

Effective air purification from grain and other types of dust is ensured RCI filters, in which the sleeves are made of needle-punched fabric IFPZ-1. RCI filters are characterized by a high degree of purification: with an initial air dust content of up to 15 g/m 3 , the dust content in the air after cleaning is 2 mg/m 3 . Regeneration of the hose fabric is carried out by automatic pulse blowing of the hoses with compressed air. The optimal interval between pulses is 10 s. Consumption compressed air for blowing one hose is 0.7 m 3. RCI filters can be used in hazardous areas of category B.

To clean the air from fine dust with a particle size of 5 microns or less, use wet dust collectors, in which the cleaning efficiency is enhanced by the fact that dust is absorbed by a water film or finely sprayed liquid. Wet dust collectors can also be used to capture explosive and toxic dusts.

Wet dust collector RISI(Fig. 23), designed for fine purification of dusty air, can be installed at the second stage after the cyclone. Detains fine mineral dust remaining after the first stage of cleaning, for example, after a cyclone in the preparatory department of oil and fat enterprises. The dust collector consists of a cylindrical chamber 1, in the lower part of which there is a conical hopper 2 for sedimentation of sludge. Inside the chamber there is a dividing cone 3 and a cylindrical reflector 4, which is connected to a diffuser 5. The smooth outline of the surface of the dividing cone at its edge ensures that the dusty flow comes into contact with the water surface at a slight angle. Dust particles in the flow are wetted with water and settle to the bottom of the hopper. The dust-free air, having passed the droplet eliminator 6, is removed to the outside through pipes 7. The sludge formed during the cleaning process is discharged through pipe 8.

Rice. 23 Wet dust collector

The degree of air purification in the RISI dust collector is 99.9%.

Several standard sizes of the RISI wet dust collector have been developed for productivity from 600 to 10,000 m 3 /h.

High-speed dust collector with Venturi tube used in a number of sectors of the food industry, including sugar factories. The main part of the installation is a Venturi tube, where the dusty air flow comes into contact with finely sprayed water. At subsequent stages of cleaning, scrubbers, cyclones and other devices are used to retain dust particles previously coagulated at the first stage.

The dust-air flow enters the Venturi pipe at a significant speed, which at the pipe neck is usually 60-120 m/s. Water is supplied using sprayers located around the circumference of the confuser. Intense turbulization is created in the neck of the Venturi pipe, which ensures good mixing of the dusty air flow with finely atomized water, wetting of dust particles and their coagulation. The air flow containing dust particles coagulated in the Venturi tube enters the second stage, where dust is collected. Water consumption ranges from 10 to 80 liters per 100 m 3 of purified air and depends on the type of dust, its concentration, as well as on the design of the cyclone. The efficiency of collecting dust particles up to 5 microns in size can reach 99.6%.

Cyclone-washer SIOT(Fig. 24) can be used in sugar factories to capture sugar and lime dust, and also as a second stage in the installation of a Venturi tube. Dusty air enters through the inlet pipe into the lower part of the device at a speed of 5-20 m/s. Water is supplied to the inlet pipe, distributed through a perforated pipe and, under the influence of centrifugal force, is thrown onto the walls of the apparatus, forming a water film. Along with the action of centrifugal force great importance To clean the dust-air mixture, the air is washed with water. Good contact purified air with water is created due to turbulization and spraying of water in the lower part of the apparatus.

Rice. 24 Cyclone-washer SIOT:

1 – body; 2 – pipe for air outlet; 3 – water supply perforated pipe; 4 – pipe for air inlet; 5 – inspection hatches; 6 – pipe for sludge removal

Cyclone with water film TsVP used to clean the air from all types of non-cementing dust, including limestone dust at sugar factories, as well as dust containing fibrous inclusions. In addition, TsVP cyclones can be used as dust collectors in installations with a Venturi tube. The TsVP cyclone consists of a cylindrical body with a conical bottom and an air outlet pipe, which contains an air-conducting volute. Dusty air is supplied through the inlet pipe located at the bottom of the cyclone at a speed of at least 20 m/s. The surface of the cyclone walls is irrigated with water using nozzles evenly located in the upper part of the apparatus. The nozzles are also located in the inlet pipe and are designed to wash away dust deposits. It is recommended to maintain the water pressure in front of the nozzles at 2.0 – 2.5 kPa. The specific water consumption is 0.1 - 0.3 l/m 3 depending on the throughput of the cyclone and the air speed at the outlet.

The degree of air purification in the TsVP cyclone is 90%, the fractional efficiency of collecting dust particles with a size of 5-10 microns is 95%.

The scope of application of wet dust collectors is limited by their disadvantages, which include the following: the formation of sludge during cleaning, which requires special devices for its processing; removal of moisture into the atmosphere and the formation of deposits in exhaust air ducts when the air mixture is cooled to the dew point; the need to create circulating systems for supplying water to the dust collector.

During the manufacturing process of various furniture products, a significant amount of fine dust and particles of the original workpieces are produced. Such dust not only worsens the working conditions of production personnel, but also contributes to possible failures of moving equipment parts. That is why mass woodworking processes require the presence of dust collection units.

Operating principle and device

The systems under consideration perform the function of collecting and removing dust and small industrial debris, which includes such unsafe components as resins, alkaloids, toxic organic and inorganic particles. When inhaled as dust, they can cause a wide range of allergic reactions, skin problems and respiratory problems. Often used in woodworking, plywood, MDF and chipboard are particularly problematic due to the adhesive resins required to make them. The sequence of action of modern dust collectors ventilation units consists of the following steps:

1. Collecting dust at its sources.
2. Extraction of small wood particles using suction fans.
3. Filtration by factions.
4. Disposal into special dust collectors.

   To achieve the assigned tasks, the dust collection installation includes an air duct system, a set of coarse and fine filters, supply and exhaust fans, and containers for waste collection. Appropriate areas are necessarily provided for when designing production areas, and the balance of energy costs includes the energy consumption to drive the moving parts of the equipment in question.

   To reduce noise levels, motors and assemblies are usually installed outside the production area. At the same time, this simplifies access for cleaning and maintenance of all components of dust collection ventilation units.

   How operating parameters are selected

   The initial indicators for choosing the size and power of a dust collection unit are:

   • Volume of air (in m3/min) that needs to be moved/removed;
   • Maximum possible dust concentration (MPC) in the room;
   • Complexity of the air duct system.

To remove fine wood dust in branches, a capacity of at least 110...130 m3/min is usually required to adequately draw dust into the main duct. Depending on how many units production equipment connected to the system and how long the ducts are, one or more ventilation units may be required.

In accordance with the hygienic standards established by Rospotrebnadzor (GN 2.1.6.1125-2002), the maximum permissible concentration of dust in woodworking areas is 0.5 mg/m3, while the maximum permissible concentration of harmful components should not exceed 30% of the specified norm. Proper installation and grounding of the collection system (and especially the duct work) is important to prevent the build-up of static electricity and to develop levels of negative pressure generated by air ventilation.

Brief description of the components of the dust collection system

The choice of filter type, number and performance is critical. Modern filtration filtration units contain washable pre-filters. They capture dust particles as small as 3 microns (smaller particles are captured by smoke filters).

Inside the filtration unit there is a disposable bag, the dimensions of which depend on the performance of the unit. In woodworking industries, it is recommended to install combined filters that allow you to purify the air both in the machine operating area and in the general room.

Some of the dust collection ventilation units come with local work lights, making them good choice for installation directly at technological equipment. Preference is given to equipment that includes a remote control.

The main requirement for a ventilation unit is the ability to capture toxic aerosols, fog, gases, vapors, smoke and dust while effectively filtering the air entering the air ducts.

The MDM-TECHNO company offers design, supply, installation supervision and supervision services for the operation of dust collection plants. Upon conclusion of the contract qualified specialists The company will carry out a technical justification for the project, select the appropriate equipment, install and connect it to a high quality level. Customers are provided with a quality certificate. Post-warranty maintenance of equipment is possible.

Ventilation dust collection units UVP (Individual chip ejectors UVP-IN series) designed to remove and clean air from shavings and sawdust and collect waste in storage bags. Chip ejectors are designed for use in small enterprises with a small amount of waste generated. The degree of air purification by the installations is 99.9%. The units are used to remove contaminated air from individual machines or groups of machines and have an air capacity of up to 7000 m 3 /hour. Due to the design, the distance from the machine to the chip ejector, as a rule, should not exceed 2 m. The installation consists of a housing with a built-in dust fan; filters and waste storage devices are attached to the housing using easily removable clamps.

CHARACTERISTICS OF CHIP EXTRACTORS UVP:

Execution options.

• To purify the air from sawdust, shavings, chipboard sawdust, plastics, etc.
• To clean the air from sawdust, dust generated as a result of processing milling machines MDF and similar materials with increased filtration area.
  When using IN series installations to clean the air from shavings, sawdust, dust resulting from MDF processing, chipboard, fiberboard and other materials in which the proportion of light fine fraction in the waste composition is relatively high, it is recommended to use filters with an increased filtration area. An increase in area is necessary to reduce the gas and dust load on the filter material. This prevents deep penetration dust particles into the material and increases the service life of the filter. The units are intended for indoor use.

Overall dimensions of dust collection units PFC

Payment Methods:

• By bank transfer for legal entities VAT included.

Delivery in Moscow and the Moscow region:

• Transport company Business Line or PEC, others by agreement.
• Items “in stock” can be picked up from the warehouse on the day of receipt Money to our bank account.
• Delivery is carried out within 1-2 business days from the moment your order is ready.

Delivery across Russia:

• Transport company (TC) Business lines or PEC, others by agreement. Delivery to the TK terminal is FREE. (3 times a week).
• Delivery costs TK depend on the region. Our managers will calculate all options and offer the most convenient and profitable delivery method for you.
• Our vehicles are extremely short time. Delivery costs are calculated based on the volume and weight of the cargo.

Guarantees

• Our company sells exclusively new products, which are covered by a factory warranty from 12 months to 36 months.

PFC dust collection units are designed for fine air purification inside small and medium-sized industrial and agricultural premises. Can be used to clean the air from wood dust and suspended shavings in woodworking industry workshops. Most dusty working environment 15/5 g/m.cub. (in the ratio of large suspended fractions / dust).

The minimum air purity at the outlet of the PFC dust collector is 0.5 mg/m3.

Design features

Dust collection units PFC have a mobile design, are produced in the form of a monoblock, and are delivered to the customer assembled in the manufacturer’s packaging.

The main components of the PFC series dust collection unit include the following structural elements:

The housing is a load-bearing steel element of a welded structure on which the remaining components and parts of the equipment are located. The housing contains a cyclone element, which performs primary gravitational air purification from large suspended particles (the first stage of purification). In the cyclone, the air swirls, due to which the particles, under the influence of centrifugal force, are pressed against the walls of the cyclone and settle in the dust collector.

At the bottom of the case there is a dust collection bag, which is removed as it is filled to clean and dispose of collected dust and debris. In the upper part of the housing there is a cassette filter made of F9 class filter paper, where fine air purification occurs (the second stage of purification). Compared to a filter bag (as, for example, in PUA-M chip ejector dust collectors), a paper cassette filter provides finer cleaning and has a longer service life.

IN basic version Together with the cassette, the unit is equipped with a manual regeneration system for the internal surface, but at the customer’s request, it is possible to retrofit the PFC dust collector with an automatic regeneration system.

The purified air is released directly into the atmosphere of the room. The air is forced to move due to the operation of a low-noise dust fan mounted on the case. An asynchronous electric motor is used as a drive. The fan inlet has round section and directed downward (it is possible to connect an air hose or a short air duct).

Manufacturing options

The standard size range of PFC dust installations includes 7 standard models.

Installations for dust and chips PFC-1250, PFC-1500 and PFC-2000 are available in a single version. The remaining models of dust collection units PFC are made in a group design (two cassettes and two dust collectors).

The selection of the required model is carried out according to the nominal performance, taking into account the actual operating conditions.

terms of Use

Settings dust collecting PFC subject to operation indoors under U2 conditions according to GOST 15150.

If you do not take special measures to remove mechanical waste and dusty air from working area woodworking machine, the surrounding space soon after the start of work becomes unsuitable for a person not equipped by individual means protection, and extremely fire hazardous. Dust collection (aspiration) installations aim to clean the atmosphere production premises, make the work of staff comfortable and safe.

APPLICATION AREA

Autonomous dust collection (aspiration) devices are used in industrial premises, which are equipped with centralized system air purification and waste removal seems impossible or impractical. Such installations are used mainly in areas for processing wood and similar materials of small enterprises in the furniture, construction and other industries.

DESIGN FEATURES

Structurally, the cleaning scheme for the mixture of air with shavings and sawdust removed from the machining zone by an exhaust fan creating a vacuum involves filtering it by passing it through a layer of fabric from which the receiving container is made. The solid component of the mixture separated by the filter is deposited in the lower part of the device, which acts as a waste storage tank.

High degree air purification, reaching 99.9%, frees workers from the need to use individual protective devices(respirators, etc.) and reduce the level fire danger up to the standard level.

The design of most modern woodworking machines provides the possibility of connecting them to a workshop aspiration system or to a dust collection unit.

Dust collecting devices are equipped with one or several filter units, consisting of fabric bags located one above the other: a filter and a storage tank. Depending on the volume of waste emitted by the equipment, you can select an installation of appropriate productivity. As a rule, several emission sources can be connected to one unit.

Many models of dust collection units can be used in vacuum cleaner mode when cleaning a production area.

MAIN ADVANTAGES

Dust collection units have become an essential element of organizing woodworking production. Without such devices it is impossible to fulfill the established sanitary standards requirements for working conditions and ensure compliance with fire safety standards.