Solid fuel pyrolysis. Pyrolysis boilers: technical characteristics, types and installation methods

If you choose solid fuel boilers for your home, we recommend paying attention to pyrolysis boilers long burning. Pyrolysis boilers are the same solid fuel boilers, but their difference is a much longer operating time and heat generation. Engineers were able to create a design in which pyrolysis boilers produce more heat with the same volume of fuel. This process is called “gas generation”, and the boiler, accordingly, is called “gas generator”.

Unit design

• Wood-burning pyrolysis boilers have 2 combustion chambers. The upper chamber is used to load firewood into it. After laying, they are set on fire and begin to burn. All pyrolysis boilers are equipped with a special controller that fully controls the combustion process. The controller also controls the built-in fans and circulation pump. All this electronic and mechanical filling creates all the conditions for the smoldering of firewood after it has begun the process of active combustion.
• When wood smolders, both smoke and wood gas begin to be produced. By turning on the fans, this gas is directed into the lower combustion chamber through special openings. Through the controller, you can set any operating mode you need and the desired temperature in your heating system. When switching to pyrolysis mode, the controller turns on the pump, which increases the efficiency of these long-burning solid fuel boilers.
• The design of long-burning pyrolysis boilers conveys quality, simplicity, reliability and durability. They use high quality boiler steel. Such steel has sufficient thickness and the necessary mechanical characteristics, which will allow the boiler for a long time maintain original appearance. This is very important under the condition of constant thermal loads, as well as regular heating and cooling to different temperatures at different time intervals.

Long-burning pyrolysis solid fuel boilers are becoming more and more popular and are increasingly used for heating private houses of various sizes, cottages and country houses, cottages, service stations, car washes, and various storage facilities and various volumes of industrial facilities, as well as various educational institutions. The units have already received many positive reviews from enthusiastic owners.

Heating with a pyrolysis boiler: where is it useful?

Pyrolysis boilers are perfect for heating any facility due to the very wide range of available capacities, which can vary from 15 to 100 kW or more. It is proposed to equip high-power boilers with a bunker, which will carry out automatic feeding fuel in required volume. This makes these boilers even more pleasant to use and saves maintenance time.

Keep up with the times - buy modern heating systems and enjoy new technologies for warmth and comfort. In our online store you can buy any heating equipment on favorable terms. Even the most demanding user will be pleased with both the price and the possibility of delivery to any corner of Russia.

What to do, if Vacation home– not gasified, and electric heating is not considered due to the high cost of electricity? If it is possible to regularly purchase or procure inexpensive solid fuel, then it is quite possible to organize an effective water heating and in such conditions. Nowadays, quite a lot of different heating devices are produced for this purpose, and among this diversity, long-burning pyrolysis boilers with a water circuit stand out.

These units are able to fully satisfy the heating needs of even a large house. At the same time, to service them you will not have to apply special effort and spend a lot of fuel, which uses wood in its various forms, coal or briquettes. Despite the fact that wood is the most ancient type of fuel, its use remains relevant to this day, due to its affordability, environmental friendliness, and ease of use.

The history of the appearance of pyrolysis-type heating devices

Even in the times of the Ancient World it was noticed that charcoal used for heating a home or for cooking is more rational than ordinary firewood, since it does not burn intensely, but smolders slowly for a long time, effectively releasing heat. Therefore, the technology for its production was invented by burning wood in chambers with minimal air access. In fact, such dry distillation of wood into coal is a classic visual example of the pyrolysis process.

Previously, holes dug in the ground were used for this - the process of converting ordinary firewood into charcoal took place in them. These chambers did an excellent job, but making charcoal also produced a large amount of thermal energy, which did not bring any benefit. The gas released by wood during oxygen-free combustion has a powerful energy potential. By the way, this made the profession of a charcoal burner extremely dangerous, since gases sometimes escaping from the pits led to severe thermal explosions.

Over time, man learned to make the most of the wood contained in it. natural energy. Furnaces were developed that successfully combined several processes - the pyrolysis conversion of wood into coal, followed by combustion of the latter, and afterburning of gases that are released during the primary thermal decomposition of fuel. Moreover, all received thermal energy from these processes, almost without losses, it is used for human needs.

At first, they tried to make conventional stoves using this design. Over time, heating devices using the principle of afterburning pyrolysis gases began to be equipped with a water circuit, due to which they began to be used in the water heating systems that are most familiar to us.

Thanks to their rational design and efficient use of the natural energy potential of wood, pyrolysis boilers fully cope with the task of a full-fledged high-power heating unit. Nowadays, not only firewood is used for their operation - more efficient and compact modern types of wood-based fuel have also been created.

Pyrolysis boiler design

General principles of the device

For a clearer understanding of how this type of solid fuel boiler works, it is necessary to familiarize yourself with information about its fundamental structure. This will greatly facilitate the further operation of the equipment.

For example, consider the following diagram:

In the diagram, digital indicators indicate:

1 – Combustion chamber, where firewood is placed.

2 – Channels for supplying secondary air, which will initiate afterburning of the gases released during thermal decomposition of the fuel.

3 – Grate-grid, which is cooled by the coolant circulating in the water circuit, thus becoming part of the heat exchange system of the boiler.

4 – Door for the production of fuel filling of the boiler.

5 – Door of the combustion chamber cleaning chamber.

6 – Door for adjusting the supply of primary air required when igniting the fuel filler.

7 – Door for cleaning the upper afterburning chamber of pyrolysis gases.

8 – Ash pan, for collecting and regularly removing solid combustion products.

9 - Pipe for connection to the chimney system.

10 – Branch pipe with a coupling or flange connection for connection to the “return” pipe of the heating circuit.

11 – Connection pipe to the supply pipe of the heating circuit.

12 – Thermal insulation layer.

13 - External casing of the heating device.

14 – Along the arrow, as well as all areas shaded in blue – this is the water circuit (“jacket”) of the solid fuel boiler.

15 – Cooling circuit, which is often connected to provide hot water supply through an indirect heating boiler.

The operating principle is as follows. After adding fuel, access to primary air for ignition opens. At the first stage of work, the wood burns normally until the temperature in the combustion chamber reaches about 400 degrees, which is necessary to start the pyrolysis process. After this, the access of primary air is reduced to a minimum, and in parallel with this, the secondary air supply channel opens. The necessary combination of oxygen, condensation of pyrolysis gases and temperature for their complete combustion leads to active afterburning with a large release of heat. This heat is taken away by the coolant circulating through the water jacket, which transfers it to the heat exchange devices of the entire heating system of the house.

Green arrows show the movement of combustion gases from the fuel fill into the afterburner chamber and further into the chimney system. The blue arrow is the flow of coolant from the return line, the red arrow is the movement of hot coolant into the supply pipe of the heating circuit.

Design features of various pyrolysis boilers

So, long-burning pyrolysis devices, in contrast to the design of conventional solid fuel boilers, are equipped with two chambers, which can be located in different ways. The first combustion chamber is intended for loading solid fuel. In it, with a minimal dosed access of oxygen, the process of its combustion (smoldering) and the release of gaseous combustion products, that is, pyrolysis gases, occurs. Then, the gases enter the second chamber of the device, where, due to the supply of secondary air, they are burned. However, it should be noted that not all existing boiler designs, called pyrolysis, fully correspond to their name.

Today, there are two main types of pyrolysis units, differing in design.

Forced air boilers

In the first version of the boiler design, the primary combustion chamber, where solid fuel is placed, is located above the secondary combustion chamber, where afterburning of pyrolysis gases is organized. A special nozzle is installed between the chambers, having straight section and made of a refractory composition similar to fireclay bricks.

In this design, air is pumped into the main firebox using installed fan, and enters partly into the furnace with solid fuel, and partly into the afterburning chamber of the released gases. In this case, it is obvious that the principle of pyrolysis is violated initially, since the fan creates an excess of oxygen instead of limiting it.

But, despite this, efficient and complete combustion of firewood occurs, with virtually no residue of even fine ash, since dry wood or products based on it burn to fine ash, and it is easily blown out through the nozzle by a fan into the chimney.

Knowing the features of this design, it can be called a “top blowing device”, since the air pumped by the fan enters mainly into the upper main combustion chamber. Due to the influx of oxygen, the temperature during combustion increases and gas production increases, but it burns quite quickly, escaping through the nozzle. In this regard, firewood quickly burns out, and it has to be added quite often in the process of heating the house. This principle of boiler operation cannot be called pyrolysis in the full sense of the word, although similar devices are sold quite often under this name.

It’s another matter if the fan standing on the outlet pipe (often called a “smoke exhauster”) creates air movement, which is proportionally divided into primary and main - secondary using the usual mechanical method or using automation. In this case, the primary air damper is located so that it is supplied precisely to the lower part of the fuel filler. The smoldering of firewood occurs from below, and the temperature released during this process promotes heating - in the middle layers of the stack, and final drying - in the upper ones.

The main air flow will be supplied only to the nozzle area so that the final combustion of pyrolysis gases with maximum number The generated heat passed through the lower chamber. Such a boiler can rightfully be classified as a long-burning pyrolysis boiler.

Boiler with natural air supply

In such a boiler design, the combustion chamber for storing firewood is located in the lower part of the device, and the combustion section of the pyrolysis gases released by the fuel is in the upper area of ​​the body.

A fan is not installed in this design, but air is supplied to light the boiler and burn pyrolysis gases in a natural way through dampers for primary and secondary air. In this version of the arrangement of the chambers and the dosed supply of air flows, the pyrolysis process is carried out properly, since instead of intense combustion, with the primary air supply damper closed, wood smoldering occurs in the combustion chamber with the release of a large amount of pyrolysis gases.

1 – fuel filler.

2 – fuel smoldering zone with the release of pyrolysis gases.

3 – primary air supply damper to ensure ignition and smoldering of the fuel fill.

4 – channel for supplying secondary air to form a gas-air mixture and ignite it.

5 – nozzles for supplying secondary air to the rear area of ​​the combustion chamber.

6 – zone of mixing of released pyrolysis gases with the air flow and their ignition.

7 – damper of the channel for additional air supply into the afterburning chamber of pyrolysis gases.

8 – chamber for intensive afterburning of the gas-air mixture with maximum heat release.

9 – pipe connecting the boiler to the chimney system.

However, this design also has its own problem. And it lies in the fact that the correct debugging of the combustion process is extremely important. When the main chamber damper is completely closed, the temperature in it decreases, as well as the formation of gases. The concentration and temperature of the gases becomes insufficient for their complete afterburning and the upper chamber turns into a regular gas outlet. The combustion products that rise into it do not burn out, but simply give off heat to the walls of the water circuit and go into the chimney. The efficiency of the boiler during such operation is sharply reduced.

If the damper is opened more than required to create the conditions necessary for pyrolysis, then the intensity of combustion in the main firebox will increase, which leads to completely irrational fuel consumption and the need for frequent refills.

To achieve perfect job pyrolysis boiler of this design, it is necessary to correctly adjust the supply of primary and secondary air, which is quite difficult to do, since this requires practical experience. Modern models have automated systems monitoring and control of processes, and with correct operation of automatic fuel loading, it is enough for 12–14 hours of operation at maximum heat transfer.

Fuel for pyrolysis boilers

Many pyrolysis boilers are capable of working not only with wood. Peat or chip briquettes, sawdust, pellets, black or brown coal can be used as solid fuel.

Each type of fuel has a different burning time, and depending on how often it is planned to add it to the firebox to fully heat the house, one or another material is selected. In addition, the duration of combustion also depends on the amount of fuel placed in the chamber. Thus, the smoldering time of soft wood is about 7 hours, hard wood and compressed sawdust or peat - 9-10 hours, brown coal 10-11 hours, and black coal 12-14 hours. True, we must not forget that different kinds fuels also differ in their energy potential.

Manufacturers of solid fuel pyrolysis boilers still call dry wood with a moisture content of no more than 20%, the logs of which are 450÷650 mm long, depending on the depth of the combustion chamber, as the optimal fuel option. It is natural firewood, especially dense hardwood, that provides the proper power of the device and maximum durability of the equipment.

It is not recommended to use wet firewood because during the combustion process they release a large amount of evaporating moisture, which leads to the formation of soot and tar deposits in the boiler chambers and chimney pipe. Such phenomena sharply reduce the efficiency of heat exchange with water circulating along the circuit, and if there are significant build-ups on the walls of the chimney, the boiler will constantly extinguish due to insufficiently intense draft.

You might be interested in information about how it works

Prices for black coal for heating

black coal for heating

Criteria for choosing a long-burning pyrolysis boiler

When deciding to purchase this type of heating device for heating your home, you need to pay attention to some factors on which the efficiency of the boiler will depend:

• The first thing you need to pay attention to is the type of solid fuel allowed for use. Of course, this factor will depend on the availability of a particular type of fuel in local conditions and the profitability of its use.
• Heating boiler power. This parameter depends on a number of initial data, ranging from the climatic conditions of the region of residence to the characteristics of the building. In the appendix to this article the reader will find a convenient algorithm for self-calculation the minimum required power to heat your home.
• The efficiency of a boiler is assessed by its efficiency. The higher the efficiency, the greater the heat transfer will be obtained with equal consumption of the same fuel.
• The most important parameters in this case are the dimensions and weight of the boiler. As a rule, such products are quite bulky, that is, it is necessary to evaluate in advance the location of their planned installation and correlate it with the dimensions of the proposed models. It would also be useful to evaluate the path along which the stabbing will be brought into the room. And the considerable weight (this applies especially to cast iron models) sometimes forces us to take steps to strengthen the base of the floor for installation of the unit.

In addition, quite often solid fuel boilers are used in conjunction with indirect heating boilers, and maximum efficiency and convenience can be achieved by installing a buffer tank (heat accumulator). Both of these devices are also very bulky and heavy, so the layout of the boiler room should be thought out in advance.

What does installing a buffer tank for a solid fuel boiler give?

The operation of any solid fuel boiler is characterized by cyclicity - alternating periods of loading, ignition, maximum heat transfer and cooling. All this is not entirely convenient for the operation of a water heating system. Installation allows you to eliminate this drawback as much as possible and increase the convenience and efficiency of operation, which is described in detail in a separate publication on our portal.

• Frequency of loading and ease of boiler maintenance. It is recommended to give preference to models with a large fuel chamber and a tray for collecting solid combustion products. In these cases, fuel can be added once or twice a day, and when using dry firewood as fuel, the pan can be cleaned once every two to three months.
• Material for making the heating device. Cast iron is considered the most durable material for this equipment. The service life, subject to all rules, is at least 30 years. However, if you plan to use it as fuel coal, then cast iron is undesirable (this alloy does not like excessive thermal loads), and it is better to purchase a boiler made of alloy steel.

By the way, the durability of a high-quality device is often limited not by its failure, but simply by “obsolescence”, when the owners come to the conclusion that it is time to purchase something more modern.

• Degree of automation. Of course, the more the boiler is saturated with automation that controls the formation of pyrolysis gases and their complete afterburning, the higher the efficiency and economy of heating, the easier the daily operation.

But solid fuel boilers themselves are quite expensive products, and the higher the degree of automation, the higher the cost of the model. So, probably, it is necessary to be able to choose some kind of “golden mean”. In addition, we must not forget about the dependence of automated boilers on the availability and stability of the power supply. If there are frequent problems with this in your area of ​​residence, then quite serious costs for the acquisition are inevitable. backup source and (or) stabilizer.

• Finally, it is necessary to evaluate the model from the point of view of ensuring the safety of its operation. It would be completely unacceptable, for example, if insufficient thermal insulation of the external casing of the boiler leads to a high probability of getting a burn if accidentally touched.

The main advantages and disadvantages of solid fuel pyrolysis boilers

In addition to the criteria for choosing such a device for heating a house, you need to know the main “pros” and “cons” of pyrolysis boilers.

To their merits can be attributed:

• In the absence of gas supply, this type of heat generator is the best option for heating a house due to its simplicity and cost-effectiveness in operation.
• Wood itself is an environmentally friendly fuel that does not pose a danger during transportation and storage. With high-quality afterburning, the release of harmful substances into the atmosphere environment substances are kept to a minimum.
• Such boilers, unlike other solid fuel boilers, do not require frequent loading. As mentioned above, this process is performed once or twice a day, depending on the specific model, additional equipment boiler room, outside temperature and the need for heating intensity.
• Such boilers are characterized by rapid heating of the coolant, and therefore the premises of the entire house.
• Cleaning from solid combustion products will also not be a big inconvenience: their quantity is minimal.

Disadvantages boilers of this type can be considered the following:

• High price for devices. It exceeds the cost of conventional solid fuel boilers by 1.5÷2 times.
• Pyrolysis boiler models can have only one circuit - the heating circuit. Therefore, if you plan to simultaneously equip your house with a hot water supply system, you will have to choose another version of the device or install an indirect heating boiler in combination with a pyrolysis boiler. Some models have pipes specially designed for these purposes.
• High demand for fuel. Pyrolysis boilers do not work well on wet wood.
• Units of this type cannot operate fully automatically, so you will have to load fuel manually and monitor its amount in the fuel chamber. There are exceptions - pellet boilers with automated feeding, but it is better to classify them as another category of equipment.
• Boilers of this type are not compact.

Review of models of solid fuel pyrolysis boilers

In specialized retail outlets, as well as in online stores, you can find a considerable number of models of various heating devices, including pyrolysis boilers with a water circuit. They are represented by domestic and foreign manufacturers and have a fairly wide range of prices and characteristics.

Domestic pyrolysis boilers

Among the most popular solid fuel units for heating a private home by consumers are the products of such domestic manufacturers as the KZKO Geyser LLC company and TeploGarant of the Burzhuy-K series.

Boilers of the company KZKO "Geyser" LLC

The Geyser plant is one of Russia's leading manufacturers of heating devices of various types and designs. The offered assortment also includes solid fuel pyrolysis models “Geyser”. The equipment is manufactured using innovative technologies from the highest quality materials.

Pyrolysis boilers are non-volatile, easy to maintain and reliable in operation, capable of heating large areas at minimal cost. In addition, heating devices have increased functionality and efficiency, since fuel consumption is significantly reduced due to its complete combustion and heat transfer to the coolant.

Pyrolysis solid fuel floor standing boilers with a water circuit "Geyser" VP series have the following specifications:

• Boiler power - 10,15,20,30,50, 65,100 kW.
• The type of fuel used is peat and sawdust briquettes, coal and firewood.
• Efficiency is about 85%.
• Product warranty from the manufacturer is 2 years

The proposed range of pyrolysis single-circuit boilers of the Geyser VP series includes models with the following characteristics and approximate cost (as of autumn 2016):

Model name	power, kWt	Chimney diameter, mm		Device weight, kg	Approximate price level
"Geyser" VP-6	10	130	390×1050×700	170	46,500 rub.
"Geyser" VP-15	15	150	390×1200×700	210	60,000 rub.
"Geyser" VP-20	20	150	490×1200×850	240	70,000 rub.
"Geyser" VP-30	30	180	600×1350×930	340	89,000 rub.
"Geyser" VP-50	50	200	660×1600×1050	650	145,000 rub.
"Geyser" VP-65	65	250	660×1930×1050	750	155,000 rub.
"Geyser" VP-100	100	250	800×1930×1200	900	230,000 rub.

The Geyser boiler is an all-welded steel structure, having several combustion chambers. The lower one is intended for storing fuel and gas formation, and in the upper one the gases are burned.

At low combustion intensity, that is, smoldering, the boiler has a higher thermal performance than stoves with conventional combustion. When operating these boilers, a minimum amount of harmful emissions and solid waste is generated. The recommended diameter of the logs used for burning is 40÷100 mm, and the length is selected in accordance with the depth of the combustion chamber.

Prices for boilers of the “Geyser” line

Sauna stove TMF Geyser

If coal is used to heat a building, it is recommended to choose a fraction of no more than 40 mm. Fuel is added to the firebox in portions, every 8-12 hours - this frequency will depend on the quality and type of fuel used.

The expected minimum service life established by the manufacturer is 10 years.

Pyrolysis solid fuel boilers from the TeploGarant plant, Burzhuy-K series

The TeploGarant plant is on Russian market no less famous brand than the previous manufacturer, and its products have gained wide popularity among consumers.

It is interesting that TeploGarant is the only manufacturer on the world market that mass-produces heating devices with a power above 140 kW. The boilers of this company have their own name - “Burzhuy-K”, and are intended for wide use both in private homes and in the industrial sector. Let's consider several models of this brand.

"Bourgeois-K Exclusive"

A series of heating units with decorative external finishing, which the consumer can select and order individually.

Therefore, if it is necessary to install a boiler in one of the rooms of the house, without violating the overall design harmony, then with the “Bourgeois-K Exclusive” series this becomes quite possible. The heating pyrolysis devices of this manufacturer are also energy-independent, easy to operate, heat the house quickly enough, and also save money on the use of expensive fuel.

Long-burning pyrolysis floor-standing boilers of the “Bourgeois-K Exclusive” series have the following technical characteristics:

• The power of the devices is 12.24 and 32 kW.
• The type of fuel used for heating is coal, firewood, sawdust and peat briquettes.
• The efficiency of these models reaches 82÷92%.
• Manufacturer's warranty – 2.5 years.

Pyrolysis single-circuit boilers The “Bourgeois-K Exclusive” series is represented by the following series of models, with the characteristics shown below. But the price in this case can fluctuate significantly, since it depends on the chosen exterior finish.

This model of pyrolysis boilers is intended for use in residential and commercial premises. The water circuit can be natural and forced circulation, that is, with installation of a circulation pump in the circuit. The device is equipped with a draft regulator, which will provide automatic control over the combustion intensity, and this factor adds comfort to the operation of the boiler.

The boiler itself is a welded structure made of corrosion-resistant and heat-resistant steel, divided into several chambers. The combustion chamber is located in the lower part of the body, and the afterburning chamber is located in the upper part. For higher heat retention and transfer, the internal walls of the device have a fire-resistant lining. In addition, between the outer wall and the water circuit there is a layer thermal insulation material– in this case, basalt wool is used for this. Outdoor decorative paneling made from natural stone.

The pyrolysis process in this boiler model is carried out in the same way as in other models of devices of this type. Thanks to the afterburning, high-quality insulation walls and lining required thermal power boiler operation is ensured with sufficiently low fuel consumption.

In the heating circuit, ordinary tap water with an acidity value not exceeding 7.2 pH, or special water can be used. However, when using the latter, the power of the heating boiler will be significantly reduced. However, this is typical for all types of boilers.

What is used as coolants in heating systems?

In terms of its heat capacity and absolute availability, water has no equal. However, there are situations when the use of water becomes impossible, and you have to resort to others. More details about this can be found in a separate publication on our portal.

The boiler kit comes with a capillary-type thermomanometer, designed to indicate the pressure of the coolant as it exits the boiler into the circuit, as well as its temperature.

Control of the set temperature of the coolant when leaving the boiler into the circuit is carried out by an automatic draft regulator. If the temperature drops, the adjustment door, under the influence of a special chain, will begin to open.

Removal of combustion product residues occurs in this design using natural draft. Bourgeois-K Exclusive boilers are energy-independent and easy to use, and if desired, this design can be supplemented with a thermal protection circuit and hot water supply.

The minimum service life established by the manufacturer is 10 years.

"Bourgeois-K Standard"

"Bourgeois-K Standard" has almost all of the characteristics listed above, with the exception of dimensional parameters and some differences in power gradation.

These models also do not have exclusive external cladding. In this embodiment, a coating of heat-resistant paint is used, applied to a metal body thermally insulated from the inside using spraying. In addition, adjustment in these models is done manually.

The parameters of boilers in this line are shown in the table below.

Model name	power, kWt	Chimney diameter, mm	Dimensions (width, height, depth), mm	Device weight, kg	Approximate price level
"Bourgeois-K Standard-10"	10	130	380×780×650	180	RUB 36,800
"Bourgeois-K Standard-20"	20	150	480×950×750	270	RUB 52,300
"Bourgeois-K Standard-30"	30	180	530×1120×840	380	66,000 rub.

The location of the chambers also does not differ from the models of the “Bourgeois-K Exclusive” line; the process of pyrolysis and afterburning of gases is carried out according to the same principle.

Prices for boilers of the “Bourgeois-K Standard” line

Burzhuy-K Standard

The efficiency of this range of models is 82÷89%, the possible power control range is 30÷110%. The operating time from one load of fuel is about 12 hours for firewood, and up to 15 hours when using high-quality coal.

"Bourgeois-K TA"

The Burzhuy-K TA pyrolysis heating unit differs from its “predecessor” in that air flow and draft are controlled automatically. The boiler is equipped with a water heating circuit, through which the coolant can circulate naturally, under the influence of temperature changes, or forcibly, using a circulation pump installed in the system.

This boiler model has all the positive features mentioned above and works on the same principle. The lower combustion chamber is also the main one, and afterburning is carried out in the upper area of ​​the boiler body.

The table presents some characteristics and approximate price levels of Bourgeois-K TA boiler models of various capacities:

Model name	power, kWt	Chimney diameter, mm	Dimensions (width, height, depth), mm	Device weight, kg	average price
"Bourgeois-K T-50A"	50	200	690×1580×1210	580	145,000 rub.
"Bourgeois-K T-75A"	75	250	820×1670×1120	900	200,000 rub.
"Bourgeois-K T-100A"	100	250	780×1890×1420	900	RUB 225,000
"Bourgeois-K T-150A"	150	300	940×2000×1820	1350	330,000 rub.

The efficiency of these pyrolysis boilers is 82÷92%. They are energy-independent and economical in fuel consumption, easy to maintain, operate and manage. The devices are quite reliable, safe and durable, but for all models of this line of units it is already necessary to equip a separate boiler room.

"Bourgeois-K Modern"

"Bourgeois-K Modern" is produced in three versions of models, different in power. they all work on the pyrolysis principle. Can work in systems with forced and natural circulation coolant

The location of the chambers in these models does not differ from the boiler designs presented above. For normal operation, it is recommended to use dry wood, but if necessary, the device can also operate on damper wood, with humidity reaching up to 50%.

The efficiency of Bourgeois-K Modern boilers is 82÷92% with economical fuel consumption.

The unit is similar in layout and level of equipment to the devices of the “Bourgeois-K TA” line, but is distinguished by a lower level of thermal power, is designed for a smaller building, and can easily be installed not in a dedicated boiler room, but in separate room residential area.

The minimum service life of the heating device established by the manufacturer is also 10 years.

Main technical characteristics model range"Bourgeois-K Modern" are shown in the table:

Name of parameters	"Bourgeois-K Modern-12"	"Bourgeois-K Modern-24"	"Bourgeois-K Modern-32"
power, kWt	12	24	32
Chimney diameter, mm	130	150	180
Dimensions (width, height, depth), mm	500×1180×800	500×1180×800	600×1270×860
Device weight, kg	220	310	430
Heated area, m²	120	250	330
Required chimney draft, Pa	18	20	22
Max. coolant temperature	95	95	95
Combustion chamber volume, l	55	61	189
Heat exchanger material	steel	steel	steel
Contents of delivery	With draft thermostat and thermomanometer
Log length, mm	550	600	660
Duration of firewood burning, hour.	5-12	5-12	5-12
Average price level	63,000 rub.	75,000 rub.	94,000 rub.

Video: presentation of long-burning solid fuel boilers of the “Burzhuy-K” series

Boilers from foreign manufacturers

In addition to domestic solid fuel boilers for home heating, products from foreign, mainly European, manufacturers are on sale. The high quality of the models and the well-deserved authority of the companies makes it mandatory short review some of them.

Pyrolysis boilers from Buderus, Logano S171 W series

The German company Buderus specializes in the production heating equipment and produces boilers various types, including solid fuel, operating on the principle of afterburning pyrolysis gases.

The Buderus Logano S171 W model range includes four models of heating devices of varying power, designed specifically for installation in private homes. The peculiarity of these boilers is that they can work not only autonomously, but also in conjunction with units running on diesel fuel, gas or electricity.

Pyrolysis boiler “Buderus Logano S171 W 50”

However, it should immediately be noted that for all devices of the “Logano S171 W” model range, a separate, carefully prepared in accordance with current rules boiler room, since for safety reasons they are prohibited from being installed in residential areas of the house.

The design of these models includes built-in control of an indirect heating boiler, provided in case there is a need to simultaneously install hot water supply in the house.

Heating devices "Buderus Logano" are equipped with modern automation, which allows you to effectively manage the entire heating system.

Prices for boilers of the Buderus Logano line

Pyrolysis Buderus Logano

The boiler body is covered with a special insulating material, which significantly reduces heat loss and also acts as a sound absorber, providing the unit with virtually silent operation.

In the design of Logano S171 W boilers, the main combustion chamber is located in the upper part of the body, and the afterburning chamber is in the lower part, the latter being insulated with fireclay lining. This arrangement of the chambers is convenient because pyrolysis begins to occur without igniting the entire fuel load.

Some characteristics and average price levels are in the table:

Model name	power, kWt	Chimney diameter, mm	Dimensions (width, height, depth), mm	Device weight, kg	Approximate price level
"Logano S171-22 W"	20	150	620×1136×1019	362	185,000 rub.
"Logano S171-30 W"	30	150	620×1136×1019	362	215,000 rub.
"Logano S171-40 W"	40	150	699×1257×1083	466	230,000 rub.
"Logano S171-50 W"	50	180	699×1257×1083	466	245,000 rub.

A few more design and operational features:

• The efficiency of boilers in this line reaches 90%, which is an excellent indicator for any solid fuel units.
• The thickness of the steel from which the device body is made ranges from 3 to 5 mm.
• Large volume of the loading chamber, which means a long fuel burning time.
• The boiler, in accordance with its design, is equipped with a fan for forced smoke removal.
• The built-in heat exchanger will keep the device from overheating.
• Automatic unit control modern type– clear interface, LCD display, advanced options for connecting additional modules.
• It is possible to connect DHW when installing an indirect heating boiler with coordinated control of the latter’s operation.
• Complete thermal insulation of the device ensures maximum operating safety and minimal heat leakage.

You might be interested in information on how to choose

Pyrolysis boilers of the Viessmann company of the Vitoligno 100-S type VL1A series

Another well-known German company that represents its products on the Russian market is Viessmann. The series of boilers “Vitoligno 100-S type VL1A” also works on the principle of pyrolysis, and has all the advantages characteristic of high-quality devices of this class.

In addition to the use of firewood, briquettes or coal, this unit provides the ability to connect replaceable burners operating on gas or liquid fuel.

Heating pyrolysis boilers of the Vitoligno 100-S series have the following characteristics and price parameters:

Model name	power, kWt	Chimney diameter, mm	Dimensions (width, height, depth), mm	Device weight, kg	Approximate price level
"Vitoligno 100-S type VL1A, 25"	25	150	526×1063×1005	461	160,000 rub.
"Vitoligno 100-S type VL1A, 30"	30	150	586×1263×1005	551	215,000 rub.
"Vitoligno 100-S type VL1A, 40"	40	150	586×1363×1089	629	RUB 265,000
"Vitoligno 100-S type VL1A, 60"	60	200	655×1757×1134	822	340,000 rub.
"Vitoligno 100-S type VL1A, 80"	80	200	749×1757×1134	864	455,000 rub.

In addition, it is necessary to mention the features and equipment of the boiler that are not included in the table:

• The depth of the main fuel chamber, located in the upper part of the boiler body, is 500 mm.
• Since the fuel chamber is located in the upper part of the furnace body, the design is equipped with a forced fan “smoke exhauster”.
• The thickness of the steel used to make the case is 5 mm.
• The design is equipped with an electronic controller that identifies operating modes.
• A protective heat exchanger is installed in the boiler to protect it from overheating.
• The efficiency of this boiler is 87%
• Easy adjustment of combustion intensity using primary and secondary air dampers - they can be adjusted manually.
• The nozzle installed between the fuel chamber and the pyrolysis combustion chamber is made of fireproof fireclay.

You might be interested in information about what it is

Pyrolysis boilers of the Wattek company of the PYROTEK series

Another European manufacturer is the Czech company Wattek, which is well known in Russia for the quality of its products, and therefore quite popular among owners of one- or two-story private sector mansions.

Modern solid fuel boilers operating on the principle of afterburning pyrolysis gases are represented by the PYROTEK model line.

You may be interested in information about what they are

Table of the Wattek product range of the PYROTEK series with some technical characteristics and price levels:

Model name	power, kWt	Chimney diameter, mm	Dimensions (width, height, depth), mm	Device weight, kg	Approximate price level.
"PYROTEK-26"	26	152	530×1145×915	318	165,000 rub.
"PYROTEK-30"	30	152	530×1145×915	322	175,000 rub.
"PYROTEK-36"	36	152	530×1145×1115	372	195,000 rub.
"PYROTEK-42"	42	152	530×1145×1115	376	200,000 rub.

In addition, devices in this line are characterized by the following features:

• The efficiency of boilers of this series is 90%.
• The ability to maintain combustion from one load of fuel for 10÷12 hours.
• It is possible to connect an indirect heating boiler with general control to the boiler for the installation of hot water supply.
• PYROTEK heating devices are equipped with a copper heat exchanger protected from overheating.
• Full automation of the boiler operation process, as it has a modern control panel that ensures maximum simplicity and ease of operation.
• PYROTEK boilers are volatile, that is, they require connection to a stable power supply.
• The body of the unit has high-quality thermal insulation made of basalt wool, located between the outer wall and the water circuit.

To conclude the topic of long-burning pyrolysis heating devices, it must be said that if the decision is made to install this boiler, then the purchase should be carefully thought out, since the prices for such equipment, as you can see, are very impressive. When choosing a specific model, you need to very carefully study its passport characteristics and check the product’s package contents.

You might be interested in information on how to equip

By the way, you can think about an individual order for the manufacture of such a boiler of the required power. In our area there are always many craftsmen who can make a boiler that in operation will be no worse than the factory model. To prove this thesis, watch the following video:

Video: long-burning pyrolysis boilers - individual production

APPLICATION

How to determine the required boiler power?

One of key parameters When choosing any boiler equipment, its power is important. By the way, other characteristics of the boiler largely depend on it, including dimensions, weight, the possibility of installation in a residential area or the need for a mandatory separate boiler room. This means that it is necessary to find the value that would guarantee efficient heating all rooms of the house, but without unnecessary excesses of power, which entails an increase in size and a sharp increase in the cost of the model.

In addition, the boiler is operating at reduced power (and this happens most of the time) heating season), the efficiency of the device and, therefore, the efficiency of fuel consumption sharply decreases. And the higher the difference between the optimal power value and its rated value, the more sensitive, and by several times, completely unnecessary losses will be.

When determining power, they are often guided by the ratio of 1 kW of thermal energy per 10 m² of room area. The approach, frankly speaking, is very approximate, since it does not take into account the multitude important factors, relating to both the specifics of the region and the characteristics of the building.

As an option, we offer our own calculation algorithm. It is based on the fact that for each room of the house an individual calculation of the required thermal power is carried out to maintain it. optimal microclimate. Then it remains to sum up the obtained values ​​- and get general meaning, which will become a guideline when choosing a boiler.

If it is necessary to make specially designed for this purpose can help.

Before you begin the calculation, familiarize yourself with the calculator interface below. For convenience, you can create a table in the rows of which you enter one by one all the rooms of your house where heat exchange devices will be installed, and in the columns - the necessary data characterizing this room.

Please note that the heat loss of each room is affected by its location relative to the cardinal points and the prevailing winter winds. If the user is not clear with these data, he can leave them as default, and the program will calculate the power for the most unfavorable conditions.

The minimum temperatures requested in the corresponding input field should not be extreme - you must indicate a level that is normal for the region of residence (for the coldest decade at home). But at the same time they do not remember some monstrous frosts, for example, five years ago, which were remembered only due to their obvious abnormality.

Further data entry fields will probably not raise any questions.

The resulting value already takes into account the operational reserve, and after summing up the total power, no corrections are required. When choosing, pay attention to models whose power is higher than the obtained value, but closest to it. This will become optimal solution. you can find out by following the link.

Among heating equipment that runs on solid fuel, the pyrolysis boiler occupies a special place. Many fables have been invented about the miraculous properties of these heat generators. We want to dispel myths and objectively present solid fuel gasifying boilers in a normal light - as effective heat sources with their own advantages and disadvantages. First, let's explain what pyrolysis is.

Briefly about pyrolysis combustion

The process of pyrolysis is the slow decomposition of carbon fuel, which occurs under the influence of high temperature and lack of oxygen. The output is flammable gas or liquid fuel, depending on the feedstock and the conditions of the chemical reaction.

Pyrolysis heating boilers produce and burn gas, hence the second name – gas generator or gasifying. Initial raw materials are dry firewood, coal, fuel briquettes.

Diagram of a gas generator plant that produces fuel for an internal combustion engine

Reference. For pyrolysis combustion, a wide variety of solid fuels containing hydrocarbon compounds are used. Example - production of liquid fuel from old car tires or burning waste in industrial gas-generating furnaces.

How wood pyrolysis occurs:

1. A certain volume of chopped wood or sawdust is loaded into a closed tank (reactor).
2. The metal vessel is heated from the outside to 500...900 °C, and air is supplied to a limited extent through the tuyeres (blown holes).
3. The tree smolders and decomposes into its components - hydrogen, methane, carbon monoxide, water vapor, carbon dioxide. At the end of the reaction, some ash remains at the bottom.
4. The resulting gas mixture is cooled, purified, and then pumped into cylinders for further use.

Before loading into the gas generator, the wood is dried. Otherwise, the heating energy will be spent on water evaporation, the pyrolysis reaction will slow down greatly, and the output will be a bunch of water vapor.

Note that any process of burning solid fuel is accompanied by the release of wood gas, even in a fire (see photo). More details in our other publication.

2 types of gas generator boilers

The operating principle of both units is the same, only combustion is organized differently. Any pyrolysis boiler has 2 chambers:

• firebox, where combustion occurs, decomposition of firewood with the release of flammable gases;
• a secondary chamber where flue gases burn, releasing additional heat.

That is, the operating principle of a pyrolysis boiler is based on separate combustion of fuel. Wood burns, gives off heat and heats the upper layers, which releases carbon monoxide and hydrogen. The mixture enters the secondary chamber and burns thanks to a separate air supply.

For a more clear description of wood and coal heat generators, we decided to use the classification of the famous Czech company Atmos, which has been producing two-chamber heaters for more than 10 years. So, boilers are divided into 2 groups:

1. Conventional pyrolysis. Here, separate air supply is organized due to the natural draft of the chimney.
2. Gasification models with forced pressurization using a fan (or smoke exhauster), equipped with automation.

Let's look at each type separately, using Atmos boilers as examples.

Operating principle of the pyrolysis unit

For description, let's take the low-power model Atmos DC15E with a maximum performance of 15 kW. The inside of a pyrolysis boiler looks like this (we use the drawing as a guide):

On the left in the photo fuel bunker with nozzle, on the right – secondary afterburner chamber

Note. The design of pyrolysis heat generators from other European manufacturers (for example, Buderus, Viessmann) is practically no different from the Atmos design, although the latter are noticeably cheaper.

The operating diagram of the DC15E solid fuel boiler is as follows. Large logs are placed in the firebox and ignited, the primary air flows through a damper in the rear wall. Further processes:

During full operation, the temperature in the firebox reaches 800 degrees, the unit reaches a maximum efficiency of 83% (declared by the manufacturer). If you “squeeze” the air with a damper and switch the boiler to long-burning mode, the efficiency will drop to 71%.

The reason is a decrease in the amount of heat from direct combustion of wood, a decrease in temperature, and a slowdown in pyrolysis. Appearance and the design of the heater is presented in the video:

Description of gasifying heat generators

In general, the design of these boilers follows the design of pyrolysis heat generators, but there are significant differences:

• primary and secondary air is pumped by a fan, usually a smoke exhauster;
• air flows are directed to the fuel from the side walls;
• the coolant temperature is controlled by an automation unit;
• the shape of the ceramic nozzle and bumper in the secondary compartment has been changed;
• a fire-tube heat exchanger is installed in the rear part;
• The boiler efficiency ranges from 81...87%, the highest flame temperature is 1250 °C (data from the manufacturer Atmos).

Sectional design of a gasification boiler. Combustion air is supplied by a smoke exhauster from holes in the side walls of the firebox (not shown in the diagram)

The principle of operation of a gasifying heater is the same - the upper compartment serves as a bunker for firewood and a gas generator, combustion occurs in the lower one. Due to the high air flow rate in the afterburning chamber, a flame torch is formed, the temperature rises, wood and coal burn better.

Gas-generating boilers of different brands may differ in small details - the shape of the firebox, the methods of air distribution in the chambers, the configuration of the nozzle. In inexpensive models, instead of shaped ceramics, a brick lining can be used, there is no water cooling circuit, and metal 4-5 mm thick can be used.

Operating rules

To get good heat transfer from a gas generator heater with minimal fuel consumption, manufacturers recommend adhering to the following rules:

• use only dry firewood, permissible humidity 12...20%;
• when installing and piping the boiler, be sure to use a three-way mixing valve or the Laddomat-21 complex device to maintain the temperature in the return line at 65 °C;
• operating coolant temperature at the supply – 80…90 °C;
• the heat generator must operate at a power close to maximum; the unit cannot be operated for a long time in low productivity mode (less than 50%);
• It is very advisable to burn with large logs, but not with round logs;
• Together with pyrolysis boilers, it is strongly recommended to use a buffer tank, which will accumulate excess thermal energy;
• The requirement for the minimum volume of the heat accumulator is 25 liters for each kilowatt of heater power.

Explanation. If cold coolant with a temperature below 65 degrees enters the boiler tank, then during the gasification of the fuel, condensation and tar will form in the primary chamber. Read more about proper strapping in a separate guide about.

The supply of coolant to the boiler must be regulated by a three-way valve. After the buffer tank, another one is installed mixing unit to lower the water temperature

The use of a buffer tank is due to the efficient operating mode of the boiler - intense combustion, outlet temperature 80...90 degrees. It is under these conditions that a high efficiency of 86–87% is achieved. You cannot “choke” a heat generator with air; the combustion efficiency will drop to 40–50%, like a homemade potbelly stove.

Real advantages of pyrolysis heaters

Let's list the advantages of gasifying boilers declared by sellers, and then weed out outright stories:

• pyrolysis heat sources are full-fledged gas generators that produce flammable synthesis gas;
• the units are very economical and environmentally friendly due to their high efficiency;
• boilers completely burn coal and wood, with virtually no residue;
• burning duration is over 10 hours (the most modest indicator is 8 hours).

The first statement is too bold. Let's remember: intense pyrolysis begins from strong heating and lack of oxygen, but what happens in the boiler? The fan pumps air into the firebox in excess, there is no smoldering. Synthesis gas, of course, is released, but direct combustion of fuel is also present.

On the left is the flame torch in the afterburning compartment during boiler operation, on the right is the fire tube heat exchanger (top view)

Let's look at the other advantages:

1. Statements about efficiency and environmental friendliness are not fairy tales. Due to decent efficiency, the boiler better utilizes fuel energy and emits much less toxic compounds into the atmosphere - nitrogen oxide and carbon monoxide. Under 1 condition: recommendations for operating mode and moisture content of firewood are fully observed.
2. The reasons for more complete combustion are dry wood and forced air injection. If you put sawdust briquettes or dry acacia into a traditional turbocharged boiler, the ash residue will also be zero. A lot of light ash is simply blown by a fan into the chimney. This means that this fact is not an advantage.
3. The duration of combustion depends on 2 factors: efficiency and capacity of the fuel compartment. In terms of efficiency, solid fuel boilers are inferior to pyrolysis boilers by 10%, which is a small increase in operating time. The main factor is the volume of the combustion chamber; if it reaches 80 liters or more, the firewood burns out in 6–8 hours.

Reference. The Czech manufacturer Atmos describes the advantages of its heat generators (literally): large fuel bunker – long burning time. Hence the conclusion: the statement about the duration of work is true, only the reason is different - the capacity of the firebox, and not the fact of generating wood gas.

There are also many tales told about the economical smoldering mode, which is simply absent in pyrolysis units. The Atmos DC15E operating instructions say so - a decrease in flame intensity leads to a decrease in efficiency and an increase in fuel consumption.

The newest heat generator “Atmos” of pyrolysis type at the exhibition “Aquatherm-2019”

Significant disadvantages of boilers

If you visit any online store of heating units and ask how much pyrolysis heat generators cost, you will immediately see their main drawback. Not the most expensive Russian boiler “Suvorov M” K-20 (20 kW) will cost 1320 USD. e., and identical in power ATMOS DC 20 GS – 2950 cu. e. For comparison: the price of the expensive traditional heater Buderus Logano S131-22 H is 1010 USD. e.

Let us outline other disadvantages of gasifying heat sources:

• 2 chambers, brick or ceramic lining plus water jacket at the bottom of the body - listed Constructive decisions significantly increase the mass and size of the units;
• high requirements for fuel quality;
• A coolant with a temperature of 80 °C is rarely used when heating private houses, which means that expensive equipment cannot be avoided;
• Ceramic lining parts do not last forever - the nozzle may crack due to overheating and will have to be replaced.

It must be said that pyrolysis boilers attract home craftsmen. But making such a unit with your own hands is very difficult; you need experience and investment in purchasing materials. It is not possible to make a heater for free. It is much easier to weld a regular or mine boiler.

Note. Judging by the reviews of boiler owners on thematic forums, use damp firewood it's still possible. The algorithm is as follows: the unit is melted and warmed up with dry logs, then wet wood is added. But the share of such fuel should not exceed 30%, otherwise soot and soot will form. Let's listen to the expert's opinion in the video:

It makes sense to choose a pyrolysis boiler from all existing boilers in this situation:

• you are willing to pay for efficiency and environmental protection;
• the budget allows you to purchase a heater and heat accumulator of the required volume;
• there is enough space in the boiler room for equipment;
• It is possible to prepare high-quality firewood, buy briquettes or dry freshly cut wood.

The heat generator model is selected according to power and functionality. How to use wood for your home correctly, read our instructions.

Initially, pyrolysis domestic boilers are designed to install a storage tank and use good fuel. This is a Western European practice, where solid fuel units cannot be operated without a buffer tank.

Our incomes are not so high, which is why homeowners save on everything - equipment, fuel, combustion method. Hence the conclusion: at the moment, gas generator installations are incompatible with the needs and expenses of most homeowners, because they cannot be operated correctly.

Reading time: 6 min

Heat supply to private houses, industries and administrative premises from solid fuel boiler houses is very common in areas where there is no possibility of connecting to a gas main or in the far north. The fuel for such boiler houses is coal, firewood, pellets and briquettes. The general disadvantage of this type of heating is that the firebox has to be regularly supplied with fuel. However, there is a type of solid fuel equipment that does not have this drawback - a pyrolysis boiler.

What is pyrolysis

This is the process of producing flammable gas and burning it in solid fuel boilers and stoves, where hot carbon monoxide is released when wood burns. When it is combined with oxygen, it burns with heat release and the formation of carbon dioxide.

IN modern technology this physical phenomenon is widespread. For example, the oven cleaning function works on this principle. Bubbling works in much the same way.
Using this property of fuel combustion, manufacturers began to experiment with designs where the fuel did not burn immediately, but smoldered in the absence of oxygen, releasing CO (carbon monoxide).

The resulting gas was supposed to be burned in another chamber. As fuel, you can use ordinary chopped firewood or special charcoal briquettes (Tyumen Pyrolysis Plant).

In addition to pyrolysis boilers, there are models that run on coal. Some work for natural craving.

Operating principle of a pyrolysis boiler

To better understand the advantages of pyrolysis boilers, you need to familiarize yourself in more detail with the principle of their operation. Despite the classic definition of pyrolysis, which states that only gases burn and give off heat, in long-burning pyrolysis boilers with a water circuit the fuel still burns in the absence of oxygen.

In fact, there is a slight smoldering with the release of carbon monoxide. In the end, two sources of heating the coolant are formed - burning, albeit weakly, fuel and combustible gas. This combustion scheme allows reducing fuel consumption by 40%.

The smoldering of the fuel produces wood gas, which enters the combustion chamber, and heated air is also supplied there. This leads to the appearance of a flame - combustion occurs with the release of heat. In this case, carbon monoxide turns into carbon dioxide and the amount of harmful substances is less than in conventional boilers.
The use of pyrolysis boilers leads to fuel savings, because more heat is obtained from the same amount of fuel.

For example, a conventional unit may require 10 cubic meters. firewood for the heating period, and 6 cubic meters will be enough for pyrolysis. And just as importantly, you won’t have to refill fuel often.

Long-burning pyrolysis boilers with a water circuit are produced in several varieties:

• non-volatile. Characterized by natural traction and mechanical control;
• volatile. Blowing equipment is used, which contributes to higher efficiency;
• with a difference in the location of the gas afterburning chamber. The chamber can be under the firebox or above it.

There may be many design options, but they do not differ in the principle of combustion. There are so-called long-burning systems that operate regardless of the type and quality of fuel and are rather than pyrolysis heating systems.
The use of volatile boilers is convenient in that they are equipped with automatic controls to regulate combustion, depending on the water temperature and the room temperature.

Long-term combustion occurs due to two factors: low smoldering intensity of the fuel and a large firebox. All this guarantees a low frequency of access to the equipment.

Design of a long-burning pyrolysis boiler

The long-burning pyrolysis boiler has the following device:

• Control block. This device selects different modes and controls operating parameters;
• Frame. Made of steel and coated with heat-resistant paint;
• Thermal insulation. Used to reduce heat loss;
• Anti-boiling device. Controls the temperature of the coolant and regulates combustion to avoid boiling, which can lead to an accident;
• Heat exchanger. A metal pipeline filled with coolant, which is heated during the combustion of fuel, after which it enters the heating system;
• Combustion chamber. Serves for loading solid fuel into it. After which ignition occurs and the air supply stops. Smoldering occurs at 450˚C;
• The combustion chamber. In this part, wood gas is burned, subject to air supply. The combustion temperature reaches 1100˚С;
• Coolant supply pipe to the heating system;
• Grate bars. Metal grate located between the loading and combustion chambers;
• Connection to the chimney;
• Chimney fan;
• Primary air valve to start pyrolysis;
• Secondary air valve for wood gas combustion;
• Return pipe.

Pros and cons of a pyrolysis boiler

Like any equipment, long-burning pyrolysis plants have both advantages and disadvantages.

The advantages include:

• Economical. Fuel consumption is reduced by up to 40% depending on the modification and operating conditions;
• Long burning. This means that after adding pyrolysis fuel you will not need to approach the boiler soon;
• Environmental friendliness. Fuel combustion occurs almost completely, so virtually no harmful substances are released;
• High heat transfer of combustion products. The temperature of the exhaust gases is noticeably lower than in conventional boilers;
• It is possible to use automatic power control devices by changing the intensity of smoldering.

The disadvantages of pyrolysis equipment are as follows:

• High price. The high cost is explained by convenience and economy;
• Dependence on energy resources. Given the availability of automation and forced pyrolysis boilers, they need to be connected to the electrical network;
• Dimensions. The dimensions are significantly larger than those of traditional solid fuel installations.

The main disadvantage is still the cost, and the rest do not represent big problems.

How economical is a pyrolysis boiler?

Design features pyrolysis boilers provide it with a significant advantage over classical ones. The efficiency of a long-burning solid fuel pyrolysis boiler reaches the performance of gas equipment and is about 90%, and the efficiency of classic ones does not exceed 70%.
To understand how economical solid fuel pyrolysis boilers are, you can perform a calculation and compare it with a type of fuel comparable in efficiency.

Price natural gas for the population varies depending on the region, but for simplicity, let’s take the city of Moscow. Its price is 4.84 rubles per cubic meter. (in other regions, generally higher). The cost of chopped firewood for heating needs is about 1,500 rubles per 1 cubic meter. Hence, 1 kg of firewood costs 1.5 rubles. The regulations indicate that 1 kg of firewood can produce 3200-3600 kcal. Caloric content of gas – 8000 kcal/cub.m. As was indicated, the efficiency of heating pyrolysis and gas boilers is comparable, so it can be neglected in the calculation.
By carrying out a simple calculation, you can see that to obtain 8000 kcal you will need to burn 2.35 kg of wood. Let's multiply by the unit cost of firewood: 2.35 kg * 1.5 rubles. We find that the cost of 8000 kcal when burning wood will be 3.52 rubles, and when burning gas - 4.84 rubles. Using a pyrolysis combustion boiler saves fuel costs by almost 30% compared to using gas equipment.

Pyrolysis plants, although expensive, are the most suitable equipment for heating greenhouses, greenhouses, and conservatories. This type of equipment is also used in waste processing plants.

Is it worth doing it yourself?

If there necessary knowledge, capabilities and drawings, then you can make a pyrolysis boiler yourself. The Belyaev pyrolysis boiler scheme is popular among the population. This technology cannot be called simple, however, it is one of the most accessible and implementable.

Boiler diagram. Photo source: balserv.ru

To make a pyrolysis boiler with your own hands according to the drawings, you need:

• metal pipe (D32,57,159 mm);
• profile pipe (20x20, 80x40, 60x30 mm);
• metal sheet;
• fireclay brick;
• air supply pump;
• temperature sensor.

In addition, you will need a tool and a welding machine. An assistant will be needed. First, the sheet parts of the installation are made, cut with a precision tool, and then, following step by step instructions, the rest of the work on assembling the homemade boiler is being completed.

Popular models

Let's consider the most common and popular pyrolysis plants, among which there are both electricity-dependent and non-electricity-dependent:

1. Popov's boiler. This model is made of steel and is the main one for making a long-burning pyrolysis boiler with your own hands. Any solid fuel can be used. The large combustion chamber allows the boiler to operate autonomously for up to 1 day. The highest heating capacity of this model reaches 1000 kW, the lowest – 25 kW. Efficiency – up to 95%.
2. Geyser. The boiler is designed for both domestic and industrial use. The household line of pyrolysis heating boilers ranges from 10 to 50 kW. The boilers are non-volatile, operate on any fuel, have high efficiency, and are easy to operate.
3. Buderus. Have high quality, mechanical control, independent of electricity. The boiler heat exchanger is made of both cast iron, which eliminates corrosion, and steel. The efficiency of Buderus boilers ranges from 78 to 87%, depending on the model.
4. Bastion. Non-volatile pyrolysis boilers with a water circuit, operating on all types of fuel. Power range – from 12 to 50 kW. They have cast iron heat exchangers, high-quality construction and low cost.
5. Wattek Pyrotek 36. Energy-dependent Czech single-circuit boilers with a power from 26 to 42 kW. They have a copper heat exchanger and are equipped with automation. Efficiency reaches 90%. Autonomous combustion until 10 o'clock.
6. Viessman. German equipment equipped with an automatic control system. Power range from 25 to 80 kW. The fuel used is wood. Efficiency – 88%.
7. Dakon. Gas-generating pyrolysis plants with power from 18 to 40 kW. Dakon boilers operate on wood and wood waste. Efficiency – up to 85%.
8. Burzhuy-K. Russian boilers power from 10 to 32 kW. Efficiency factor – 85%. Industrial pyrolysis boilers with a power above 200 kW are also manufactured.
9. Teplodar42. Russian pyrolysis coal boilers. They have a wide range for private houses, cottages, administrative buildings and industry.
10. Fortan. Pyrolysis equipment for processing various types of waste. They are distinguished by environmentally friendly operation during disposal; they efficiently process household, rubber, industrial and medical waste.
11. Sime. Italian equipment with power from 22.5 to 38.7 kW. They have a cast iron heat exchanger and high efficiency.

Among Russian manufacturers, we can highlight the products of Klimov Pyrolysis Equipment Plant LLC, Barnaul.

Installation

Pyrolysis boilers can be installed in systems with both natural circulation and forced circulation. When installing a boiler in a system with natural circulation, it is necessary to take into account the slope of the pipes; in a system with forced circulation, it is important to select the correct pumping equipment.

Since the heat exchanger is prone to low-temperature corrosion, the temperature of the coolant in the return pipeline should be monitored so that it does not cool suddenly. It is recommended to keep it at least 60°C.

This is done by mixing the return water with hot water from the supply pipe. Proper strapping is of great importance.

Strapping diagram. Photo source: artosfera.ru

Before starting work, it is necessary to fill the system with water. Then you need to adjust the air supply mode to the combustion chamber of the pyrolysis gases to ensure the required operating mode.

The quality of combustion of gases can also be determined indirectly - by assessing the smoke coming out of the chimney: if it does not have a strong odor and a dark hue, then the fuel burns correctly.

If heavy pyrolysis resin leaks from the boiler during operation, this indicates a low temperature in the firebox, an incorrectly selected chimney cross-section or the need to clean it.

The problem can also occur in a homemade boiler. During the first time after installation, the boiler is tested and must be under constant supervision. The fuel load should be about two-thirds of the firebox volume. Once the testing has been passed, it can be operated at full capacity.

Content

1. Diagram and structure of a pyrolysis combustion boiler
2. Operating principle of a pyrolysis heating device
3. Advantages and disadvantages of pyrolysis boilers
4. Installation and installation of pyrolysis type boilers

Introduction

Every owner of a private home, when choosing a solid fuel heating boiler, undoubtedly wants to make the best choice. One of the main criteria that all buyers, without exception, pay attention to is efficiency. Among the variety of devices presented on the Russian market, there is one type that uses a special method of burning it - long-burning pyrolysis boilers. Let's try to figure out how such a boiler works and how it is designed, and also consider its main pros and cons.

Diagram and structure of a pyrolysis combustion boiler

The essence of pyrolysis can be explained using the example of a long-burning wood-burning boiler. Under the influence of high temperatures in the firebox (about 450 degrees Celsius), wood decomposes into solid and gaseous components. Subsequently, each of these components is burned separately. Heating devices of this type are also called gas generators, and the method itself is called the dry distillation method. Thanks to this technology, better efficiency is achieved and less wood consumption than when using classic way, but the price of the device increases significantly.

The main types of fuel for long-burning boilers using the pyrolysis method are: wood, coal, peat, sawdust, pellets. The main fuel requirements are as follows:

• limited dimensions

  The dimensions of the bookmark should not be larger than the dimensions of the firebox. In the case of using wood logs, their length is usually limited to 40cm and diameter to 20cm.

• low humidity

  To obtain high efficiency, as well as to extend the service life of the boiler, it is necessary that the humidity of the fuel used in it does not exceed 20%.

Photo 1: Automatic feeding system for pellets into the pyrolysis boiler

According to the type of fuel used, all types of pyrolysis boilers can be divided into:

• wood burning

  Structurally, designed to work on wood. It is with this fuel that they provide the best efficiency. The most famous model of this type is

• coal

  The main type of fuel is brown coal or coke.

• pellet

  Such boilers operate on pellets - pressed fuel granules from wood processing waste.

• combined (or universal)

  Can work on any of the above listed types fuel. The efficiency of universal long-burning boilers is usually worse than those designed for a specific type of fuel.

Photo 2: Construction of a wood-fired pyrolysis boiler

Depending on how many contours the structure contains, the following are distinguished:

• single-circuit

  The hot water boiler contains one circuit, which is used to heat the house.

• double-circuit

  The design provides an additional circuit to provide hot water supply.

Below is a diagram of a pyrolysis boiler, looking at which we will analyze its structure. A long-burning domestic heating boiler usually consists of the following main elements:

Photo 3: Design diagram of a pyrolysis boiler

• Control device

  The automatic boiler control unit is designed to set various boiler operating modes. This device allows you to control various parameters operation of the heating device.

• Frame

  The outer frame is made of steel and coated with special heat-resistant and wear-resistant paint. The use of special paints in heating boilers is dictated by their operating conditions and temperature conditions.

• Thermal insulation

  To reduce heat loss from the pyrolysis boiler, it is thermally insulated. Mullite-silica boards, asbestos, diatomaceous earth, and lime are used as materials for thermal insulation.

• Boiler boiler prevention device

  This device allows you to keep the boiler temperature within the required limits. Boiler boiling is very dangerous and can lead to boiler failure and, in some cases, to an explosion.

• Heat exchanger

  The heat exchanger is a cast iron or steel container that is filled with coolant. In its upper and lower parts there are valves for connecting the supply and return lines of the heating system. During the combustion process, the coolant inside the heat exchanger heats up and circulates through the heating system.

• Load chamber

  The loading chamber (gasifying or combustion chamber) is a compartment into which solid fuel is loaded. After loading and igniting fuel, the supply of primary air decreases. The combustion process slows down and the fuel begins to slowly smolder, releasing pyrolysis gas. The temperature at which this procedure occurs is approximately 450C. The resulting gaseous mixture is forced into the next compartment, called the combustion chamber.

• The combustion chamber

  In the combustion chamber, a mixture of wood gas and secondary air is burned. This mixture is supplied forcibly from the gasification compartment. The combustion process takes place at a temperature of 1100C.

• Flow connection

  The supply pipe is used to supply hot water from the boiler to the heating system.

• grate

  The grate is a cast iron or steel grate located between the loading and combustion chambers. Gasification of solid fuel occurs on it, and through holes in it, pyrolysis gas is pumped into the combustion chamber located below.

• Chimney pipe

  The chimney is a channel for removing combustion gases. The length and cross-section of the chimney should depend on the boiler power.

• Chimney fan

  Since most use top blast, it is necessary to use forced draft using a fan or smoke exhauster.

• Primary air valve

  Primary air is intended to preheat the fuel and begin the pyrolysis process.

• Secondary air valve

  Secondary air is necessary for afterburning pyrolysis gases in the combustion chamber.

• Return line connection

  Through the return pipe, the coolant from the heating system returns back to the heating device.

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Operating principle of a pyrolysis heating device

So, how does a pyrolysis boiler work? Let's look at the step-by-step diagram of its operation using the example of a coal-fired pyrolysis boiler:

Stage 1:

Solid fuel, in our case coal, is loaded into the firebox. The boiler lights up and the door to the combustion chamber closes tightly. Since the supply of primary air is limited, the process of smoldering and the release of pyrolysis gas begins. The duration of combustion can be controlled by adjusting the supply of primary air.

Photo 4: How a coal pyrolysis combustion boiler works

Stage 2:

A mixture of pyrolysis gas and primary air is forced into the combustion chamber through holes in the grate. Secondary air is also supplied there to ensure combustion intensity. The process of combustion of a mixture of pyrolysis gas and secondary air occurs at high temperatures. The resulting thermal energy heats the coolant inside the heat exchanger.

Photo 5: How the pyrolysis gas afterburning system works

Stage 3:

Through the flue, through forced draft with the help of a smoke exhauster, gaseous combustion products are released into the atmosphere. It should be especially noted that the exhaust gases generated as a result of pyrolysis combustion contain a minimal amount of harmful impurities. The majority of flue gases are water vapor and carbon dioxide.

As you can see, the operating principle of a pyrolysis boiler is somewhat more complicated than a traditional one. That is why their cost is usually 2 times higher. Before deciding which boiler to buy, pyrolysis or classic, let's look at the pros and cons of pyrolysis combustion boilers.

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Advantages and disadvantages of pyrolysis boilers

The use of pyrolysis technology has both advantages and disadvantages. The main advantages of long-burning pyrolysis boilers are:

• Burning duration

• Increased efficiency

  When using pyrolysis combustion, solid fuel burns much better. To obtain the same amount of heat using pyrolysis, less fuel will be required than with traditional combustion.

• High efficiency

  The efficiency when using pyrolysis is much higher. The range of efficiency values ​​for pyrolysis boilers is 85-92%.

• Environmental friendliness

  The composition of the gases at the outlet of a pyrolysis type boiler is almost completely free of harmful impurities. The main part of exhaust gases consists of water vapor and carbon dioxide.

• Adjustable

  The gas generation process is easy to adjust. Therefore, most often pyrolysis boilers are automatic. Adjusting the combustion intensity allows you to adapt to the needs of the heating system.

Photo 6: Automatic household gas generator boiler

In addition to the advantages we have discussed, they also have a number of disadvantages. Let's take a closer look at them:

• Energy dependence

  The design feature of the pyrolysis boiler is that the supply of primary and secondary air, as well as draft, is carried out forcibly using fans that require electricity. However, there are also energy-independent models with natural draft, but they are quite rare.

• Requires low moisture content

  The gas generation method is very sensitive to the moisture content in solid fuel. The drier the fuel used, the better. Recommended humidity no more than 20%

• Full download required

  With a small amount of fuel, pyrolysis boilers begin to burn unstably. Therefore, it is recommended not to load less than 30-50% of the manufacturer’s recommended rate.

• Difficulty in automatic fuel supply

  For wood-burning pyrolysis boilers, it is difficult to organize automatic fuel supply due to the large size of the logs. It is possible to make an automatic long-burning coal boiler only if the size of the coal fractions is uniform.

• High price

  The high cost of long-burning gas generator boilers is one of their most significant disadvantages. You can buy such a boiler at 1.5-2 times more expensive than devices of similar power, but using traditional way burning.

For more information about pyrolysis-type heating devices, their advantages and disadvantages, watch the video: