Pyrolysis boilers with and without a water circuit are highly efficient equipment for high-quality and quick heating of premises. Hi-tech underlying manufacturing, absolute safety, high heating speed and other advantages distinguish these devices into a separate group of modern heating devices, which have already managed to occupy a worthy niche in the market, acquire a wide audience of fans and positive reviews.
Firewood placed in the boiler chamber gradually burns and smolders. When there is insufficient oxygen, in addition to heat, smoke and a certain amount of flammable gases are formed. Unlike wood fuel, anthracite consists almost entirely of carbon, which suggests a lesser heating effect and the release of only carbon monoxide. The composition of firewood is largely dominated by cellulose (carbohydrates) and contains a decent amount of water, so this type of fuel emits a wide variety of substances.
The combustion time of the gases is minimal, and practically no soot is formed during the combustion process, which has a positive effect on the efficiency of the heating device. To activate the process of gas evolution, the boiler should be warmed up well. Most often, a special design is used for this. Despite the fact that gas generator boilers are slightly more expensive than conventional solid fuel models, these costs will more than pay off in the near future.
The boiler design includes 2 chambers: the lower one is intended for pyrolysis, and the upper one is for combustion of gases released during the combustion process. Since all processes occur under the influence of high temperatures, all elements and the boiler body must be made of heat-resistant materials. Most often, manufacturers resort to cast iron due to its super strength, good resistance to corrosion and temperature effects. You can often find boilers made of steel, which heat up very quickly and also cool down quickly. Such designs provide for the presence of a special ceramic coating, which protects steel from burning.
The operating principle of a pyrolysis boiler is the process of generating pyrolysis gas from solid wood at temperature conditions from 200ºС to 800ºС and a lack of oxygen and subsequent afterburning of the released gases, which are mixed with secondary air already in the afterburning compartment.
For this:
Important! Since pyrolysis boilers long burning with a water circuit for domestic use are modern and efficient heating devices, then they provide the ability to easily and effectively control the combustion process. In addition, they solve the problem of creating favorable conditions for the formation of the maximum amount of released gases and heat.
Equally productively, solid fuel boilers can operate on any solid fuel - it can be peat, coal (both black and brown), ordinary wood, fuel briquettes. Since all the mentioned raw materials have their own distinctive features and quality, their complete combustion time is also excellent. For example, the combustion period of soft wood is 5 hours, hard wood is 8 hours, and the combustion time of coal is already 10 hours.
In this regard, the opinion of experts is also interesting: they all unanimously claim the high productivity of boilers operating specifically on hard and dry wood. To achieve maximum performance, good heating of the room and long-term trouble-free operation of the equipment, it is recommended to use dry firewood, the length of which does not exceed 60 cm, and the humidity is 20%.
Important! The color of pyrolysis gas is almost white, and no by-products should be formed during combustion. However, if excessively high humidity solid fuel, the appearance of tar and soot, a sharp decrease in the calorific value of the equipment and even its spontaneous attenuation cannot be ruled out.
Comparing wood and other solid fuel raw materials that can only be used for uninterrupted operation pyrolysis boiler, with gas, one can note the availability and environmental friendliness of the former, the high cost, and in some cases the impossibility of constructing a gas pipeline.
As for solid fuel, there is plenty of it in every Russian region, and its transportation requires only a highway and a spacious vehicle. For many rural residents, pyrolysis boilers running on solid fuel resources are a real salvation.
Before purchasing and installing such heating equipment, you should carefully identify and analyze all the pros and cons of a particular model or type of boiler.
Thus, a long-burning pyrolysis boiler has a number of undeniable advantages compared to other heating devices:
Long-burning pyrolysis boilers, unfortunately, are not without their drawbacks. One of the main disadvantages is the price of the device. Regardless of the manufacturer and design features of pyrolysis boilers, they are all somewhat more expensive than other solid fuel appliances.
In addition, these boilers are single-circuit devices, which are not intended for heating water for domestic needs. Another disadvantage, which was already mentioned earlier, is the sensitivity of the equipment to wood moisture: at high humidity levels, the efficiency and operating efficiency of the device may decrease. It is impossible not to note the impressive size of the unit. And finally, regulation of combustion intensity is possible only in manual mode; full automation is not provided.
The performance of heating equipment, the efficiency and speed of heating the premises, in addition to fuel resources and their humidity, are influenced by the following factors:
If you have the opportunity to inexpensively buy or prepare wood in advance, then you can safely and without doubting the high performance of the work for a long time, buy and install a long-burning pyrolysis boiler at home.
If you are not at all sure of this possibility, then we recommend paying attention to a boiler whose firebox combines 80% pyrolysis compression of solid fuel resources and 20% conventional. These devices are considered combined, since they allow high-quality combustion of not only traditional firewood, but also wood and coal waste, peat waste, as well as any other fuel mixture, the humidity of which will be less than 50%. Such a combined heating device is capable of burning about 80% of solid fuel in pyrolysis mode, and the remaining 20% in the mode of the most ordinary boiler, which runs on solid fuel resources.
When purchasing a boiler, be sure to visually assess the volume of the loading chamber. The best option would be a device whose loading capacity will be able to accommodate wood 65 cm long. The coating of the chambers is also important: the presence of ceramic concrete guarantees the integrity of the compartments at maximum heating, protects the walls from burnout and ensures the necessary combustion of raw materials.
Attention! Check out the technical characteristics of the equipment you like. Special attention Pay attention to the duration of combustion of fuel resources: the average combustion duration should not be less than 10 hours.
Until recently, when choosing fuel for almost any boiler, preference was always given to gas, and hard species remained in second place. But technological progress does not stand still, and modern technologies allow high-quality use of any type of fuel, including solid fuel. For this purpose, special pyrolysis boilers were developed.
The heating unit operates on a principle based on pyrolysis. Thus, during the smoldering process, fuel breaks down into two components: coal and gas. Slow burning is achieved by limiting the air supply to the oven. The decomposition products in the form of gas are captured to participate in further thermal processes.
Pyrolysis gas is diluted with air and burned at higher temperatures. As a result of this interaction, heat is transferred.
Depending on the quality of the fuel that is burned, the type of heating equipment is determined.
There are two types of pyrolysis furnaces:
They differ in the quality of the fuel they burn.
For them it is necessary to use fuel with minimal moisture. This will ensure a long service life. The maximum value should not exceed 25%.
The use of high-quality wood allows you to obtain 4 kW/hour with smoldering 1 kg of fuel. This great option for heating the house.
Long-burning pyrolysis boilers of this type are not too picky about fuel. Peat, wood waste, as well as low-quality coal can be used. The humidity requirements are not as high as in the previous version - humidity up to 50% is allowed.
But raw wood (waste) reduces the power of a wood-burning boiler by 2 times. This is due to the fact that wet fuel burns poorly and produces a lot of smoke.
Wood and its waste can be used in various forms:
Firewood is produced mainly from deciduous wood, but coniferous wood is also used. In addition to wood, they can be used different kinds coal The choice of fuel depends on its combustion time. This indicator has different meanings:
Characteristic feature The design is the presence of two chambers in the firebox. The upper chamber is intended for loading firewood and the primary smoldering process. In the lower chamber, a mixture of gases is burned and heat is released. They are separated from each other by a gasifying nozzle. Most often it is made of refractory concrete. The firebox is the main element, but in addition to it, the design also includes the following components:
The designs of boilers may be different, but there are no significant differences in the principle of operation. It is indicated by several operations:
The entire operating cycle of a heat generator can be determined in two main stages:
The heat released during the process warms the air. The use of a pyrolysis mechanism puts the gas generator a step above a direct combustion wood boiler.
If the boiler is working properly, the burning flame will be yellowish-white. To achieve this, it is necessary to start the equipment correctly: before loading coal or other fuel, the loading chamber should be heated to a temperature of 600–800ºС.
After loading the fuel, it ignites, and now you can switch the equipment to the pyrolysis cycle. It is also necessary to include the additional draft provided by the smoke exhauster. Sticking to simple rules, it is possible to ensure slow oxygen-free combustion of coal with useful heat release.
The entire process of combustion and heat generation is automated, unlike direct combustion furnaces. The equipment also allows you to adjust the power within the range of 50–100%. In addition to these parameters, their operation is associated with a number of advantages:
In the absence of access to the gas main, pyrolysis solid fuel boilers are the best option for heating equipment.
The large list of advantages may be slightly overshadowed by a number of disadvantages. Before choosing such a heating unit, you should study the disadvantages:
Long-burning pyrolysis boilers are used in both civil and industrial premises. If we're talking about O large areas, the choice of such a heat source will be the best option. Installing a generator in a small house is impractical and does not justify itself.
The main problem solid fuel stoves, there was always the release of smoke and gas. In addition to the smell, toxic fumes also entered the air. The pyrolysis process solved this problem by completely burning the fuel, so side effects are kept to a minimum.
The environmental factor is becoming more and more a priority when choosing a heating source. Very often, furnaces are used in woodworking and light industry enterprises. With their help, waste is disposed of and sufficient heat is generated to heat the house.
Pyrolysis boilers are becoming increasingly popular every year when installing a heating system. Although they have several disadvantages, options such as high efficiency and environmental friendliness completely compensate for them. Gas generators have a high cost, which is 1.5 times higher than classic version. But they will pay off in as soon as possible by reducing fuel consumption.
Modern boilers operating on solid fuel increasingly use the pyrolysis process in their operation. The operating principle of heating equipment is based on the ability of wood, when burned, to release a large number of carbon dioxide.
A long-burning pyrolysis boiler accumulates heat obtained during the combustion of fuel from wood or its waste and afterburning of the released gas.
As a result of modifications and design solutions, the following advantages and characteristics were achieved:
Dependence on electricity can be solved by installing an uninterruptible power supply. The voltage consumption in boilers is 150-300 W/hour.
Factory-made briquettes, wood chips and sawdust have a moisture content of 8-18%, which is the optimal moisture content for the pyrolysis process.
A short review of long-burning pyrolysis heating boilers using solid fuel helps to identify models in demand by domestic consumers:
Low-power boilers, up to 20 kW, depending on the manufacturer, cost from 60 to 350 thousand rubles. The German Buderus and Wismann are the most expensive.
Domestic Termofor and Burzhuy-K belong to the middle price category. Czech Watteks are expensive, almost like their German counterparts, which somewhat limits their popularity.
Economical and efficient heating- the dream of every homeowner. Happy are those who have the opportunity to connect gas boilers, the rest have to choose between solid fuel boilers and electric ones. Solid fuel ones are good because heating is relatively inexpensive. Their disadvantage is that they require constant presence in order to supply fuel. But recent developments - long-burning pyrolysis boilers - have become more convenient in this regard.
One load of fuel can heat the system for 8 to 24 hours (depending on the fuel and ambient temperature). In the interval between stacking firewood, it doubles, and you can check it once a month - such fuel can be supplied automatically as needed.
They have disadvantages. Not without it. Two main ones: the equipment is expensive and very often volatile (a guaranteed power supply is required). The price pays off during operation: with one stack of firewood the house will take twice as long to warm up, and with one stack of firewood it can take up to a day. In addition, there are boilers that burn everything: even construction waste and old tires. Anything that can burn.
How is it that so much energy can be produced from such a small amount of fuel? The thing is that most of the heat in conventional boilers (they are called direct combustion boilers) literally “flies” into the chimney.
If you heat with wood or coal, you know that it is impossible to touch the pipe - the temperature there is 300 o C and can be 400 o C. And in some cases (in bathhouses, for example) even higher.
In pyrolysis colas, the air leaves the firebox at a temperature of 130-160 o C. This is achieved due to the fact that not only the energy released by the firewood is used, but also the gas that they emit during smoldering is burned (a special mode is created for this).
The work is based on the fact that carbon-containing fuel (coal, firewood, pellets) when burned with a lack of oxygen, decomposes into a large amount of gases and combustible substances. Due to the fact that during the smoldering process a large amount of flammable gases is released from wood or other carbon-containing fuel, such devices are also called gas generator boilers. For example, wood as a result of pyrolysis is converted into:
All these substances burn and release a large amount of energy. Pyrolysis boilers therefore have two chambers:
Air is supplied to both chambers separately; its quantity regulates the combustion intensity and boiler power by at this stage. This is the only combustion technology that allows you to automate the burning of wood or coal.
The release of gases during combustion in conditions of lack of oxygen occurs very actively. Because for efficient work In such equipment, automation is important, which will control the process: limit the supply of oxygen after the firewood has flared up and regulate the process in both chambers. This is the main disadvantage of the stake: it needs guaranteed power to work (for the automation to work).
There is one more positive point: Pyrolysis gases interact with carbon during combustion. As a result of these reactions, at the outlet of the boiler, the smoke consists mainly of carbon dioxide and water vapor with a small amount of other impurities. If firewood is used, CO emissions into the atmosphere are three times less than when using traditional technology. When working with coal, the situation is even more rosy - emissions are reduced by a factor of five.
The afterburning of gases and microparticles contained in it is also good because there is practically nothing to be deposited on the walls of the chimney: little soot is formed. And one more bonus: there is little ash left. Less ash and soot - less cleaning required. This is also nice.
Direct combustion boilers have an efficiency of about 60-65%. Pyrolysis – 80-90%. This is a noticeable difference.
But the benefits aren't over yet. The power of a conventional boiler can be adjusted quite arbitrarily. All possibilities are to open/close doors, vents and dampers. Moreover, you need to do this with your hands and rely on experience and intuition. The pyrolysis process can be controlled according to wide range: you can leave 30% of the power, or you can “overclock” it to 100%. And the process is regulated by automation, which focuses on given parameters. Result: fuel savings of 40%.
Structurally, colas can be made in different ways: in some models the afterburner chamber is located under the primary one, in others – on top. There are models in which it is located behind the primary firebox. In some units, air is not supplied from below the firewood through the grate, but is “blown in” from above, slowing down the combustion process. These are all variations of the same technology. But they also have their pros and cons. Let's look at some of them in more detail.
These boilers were developed by engineer Yuri Blagodarov. Their main advantage is that they have non-volatile models. They do not use artificial air injection; the boiler operates on natural draft.
The thoughtful arrangement of fuel bunkers, afterburning chambers and the use of a catalyst (bath stone) made it possible to decompose not only simple carbons, but also complex ones. Due to this, the number of types of fuel has expanded significantly, and the efficiency of its distillation has also increased.
Another distinctive feature of these boilers is the ability to use raw firewood without loss of power. Blago boilers of industrial capacity can operate on wood with 55% humidity, low-power units successfully cope with 35% humidity.
The design is constantly being improved. IN Lately The production of equipment for burning used tires has been launched, and there is specialized equipment that runs on coal.
Conventional long-burning pyrolysis boilers “Blago” use firewood, sawdust, wood chips, scraps and their mixture with coal chips. When using firewood, in principle, you don’t have to split it—even small logs of wood burn well.
As a result, the boilers are truly omnivorous: they work on old tires, rubber, leather, polyethylene, not to mention traditional types of solid fuel.
Large Blago pyrolysis boilers have several fuel chambers (at least two). If necessary (slight frosts outside), you can put fuel in only one. The efficiency (81-92%) of the boiler does not change due to this, only the power becomes lower. For example, a 50kW boiler can be used at 12kW. Moreover, during the system acceleration period it will produce 25 kW, and the rest of the time - 12-15 kW. There are small models (from 15 kW) with one fuel loading chamber.
Blago long-burning pyrolysis boilers are produced with a power from 12 kW to 58 kW. More powerful units are made to order with matching input and output parameters. For units from 1 MW, an automatic fuel supply line can be developed (this is data from the message of the author of the project).
What does the manufacturer guarantee besides “omnivorousness”? Firstly, the amount of fuel required is smaller - it is needed by 20-30% compared to other boilers of the same operating principle. Secondly, long burning - fuel is added every 12-18 hours. Thirdly, high safety: the loading door and combustion valve are combined, which prevents accidental ignition during fuel loading; automatic adjustment of the plug is provided to prevent gases from escaping if installation rules are violated. Fourth, ease of use: automated control, no smoke when loading fuel, automatic cleaning of fuel channels.
Now about the shortcomings that are pointed out on the forums:
Yes, not cheap. But everyone is sold a package of documentation for self-production.
| Model | Power | Square | Maximum system volume | Dimensions, mm | Fuel | Coolant | Price |
| BLAGO-TT 15 | 15 kW | 150 m2 | 0.83 m 3 | 1200*530*970 | Firewood, wood waste | 48 t.r. | |
| BLAGO-TT 20 | 20 kW | 200 m 2 | 0.60 m 3 | 1200*530*1140 | Firewood, wood waste | Water, non-freezing liquid for heating systems | 60 t.r. |
| BLAGO-TT 20 | 25 kW | 250 m 2 | 0.75 m 3 | 1540*725*950 | Firewood, wood waste | Water, non-freezing liquid for heating systems | 75 t.r. |
| BLAGO-TT 30 | 30 kW | 300 m 2 | 0.84 m 3 | 1540*725*110 | Firewood, wood waste | Water, non-freezing liquid for heating systems | 90 t.r. |
| BLAGO-T2 Т-BH-40 | 40 kW | 400 m 2 | 120 l | 2300*1100*1100 | Firewood, wood waste | Water, non-freezing liquid for heating systems | 120 t.r. |
| BLAGO-T2 Т-BH-50 | 50 kW | 500 m 2 | 168 l | 2300*1100*1300 | Firewood, wood waste | Water, non-freezing liquid for heating systems | 150t.r.. |
| BLAGO-T2Т-BC-40 (built-in heat exchanger) | 40 kW | 400 m 2 | 1805*1100*1100 | Firewood, wood waste | Water, non-freezing liquid for heating systems | 120t.r. | |
| BLAGO-T2Т-BC-48(built-in heat exchanger) | 48 kW | 480 m2 | 1805*1100*1300 | Firewood, wood waste | Water, non-freezing liquid for heating systems | 144t.r. |
But the last two drawbacks are the result of little experience working with this boiler and the incorrect position when lighting the ash pit. Some consumers do not like the excessive discharge of the heat exchanger walls, which makes it difficult to load fuel (models TTS and TTU).
The Czech company Atmos produces more than 200 models of heating boilers that burn wood, diesel fuel, briquettes. There is equipment that runs on several types of fuel; gas boilers are made to order.
Long-burning pyrolysis boilers Atmos are produced both for heating small rooms with a power of 15 kW (90-180 m2), and for production premises up to 1000 m2 and more.
They consist of two chambers located one above the other: at the top is a fuel chamber, at the bottom is a gas afterburning chamber. Cameras (one or both) may have ceramic finish, which increases the efficiency of heat use - it is not dissipated through the walls, but is used to heat the coolant. The fuel bunker has big sizes, you can even put quite large whole logs there. This reduces the power, but increases the combustion duration (can be used in warm weather, when high temperature in the system is not needed).
Atmos produces pyrolysis boilers using different fuels:
The boiler marking also contains the prefixes GS, GSE and S. The first two types have an all-ceramic finish on both fireboxes, resulting in higher efficiency and a significantly lower percentage of carbon dioxide emissions into the atmosphere. Despite the fact that the cost of such devices is almost 50% higher, practically only equipment of this type is sold in Europe. In our country, the lion's share of sales falls on less efficient, but cheaper boilers marked S without ceramic coating of the fireboxes.
Long-burning pyrolysis boilers Atmos: prices and technical characteristics (click on the picture to enlarge its size)
Boilers from the German company Bosch can be used as main or backup heating equipment. They are distinguished by a wide ability to regulate power (by changing the operating mode of the smoke exhauster, you change the power of the heating unit). Boiler efficiency is 78-85%, the volume of water in the system is 76-124 liters.
Technical characteristics of the long-burning pyrolysis boiler Bosch Solid 5000 W-2
Boilers operate only on wood with a moisture content of up to 25%; you can use briquettes from wood materials. The design is similar to their Czech counterparts: on top there is a fuel loading and gasification bunker, and on the bottom there is a gas afterburning chamber. Between them there is a ceramic burner. The cost of such boilers starts from 2000 euros.
Another video material that explains the principle of operation of solid fuel pyrolysis boilers
According to the laws of physics, any solid body, with intense heating and limited air access, releases a certain amount of gas. According to experimental calculations, each material has a different percentage of CO produced.
Nai large quantity gas released by wood. It is on this physical law that the operating principle of a wood-fired pyrolysis boiler is based.
The operating principle of wood-burning pyrolysis boilers for heating a house is as follows:
Additionally, pyrolysis equipment can be classified according to the following differences: 
The pyrolysis process can begin only under certain conditions: high temperature in the combustion chamber, limited oxygen supply. There are also requirements for wood moisture content - no more than 20%.
But, all of the listed advantages become possible only if you learn how to properly heat the heat generator. There are a few simple rules:
During the first firing of the boiler, it is possible that unpleasant odor indoors, appearing during the paint polymerization process.
Pyrolysis boilers work better when burning dry hardwood. A certain humidity can be achieved by natural drying firewood
The frequency of loading firewood and the operating time from one bookmark directly depend on their quality. Well-dried fuel gives more heat and provides normal conditions for the start of pyrolysis.
