Do-it-yourself brick pyrolysis oven ordering. Long-burning pyrolysis furnaces: do-it-yourself device and methods of making

Pyrolysis is a process in which the thermal decomposition of fuel occurs. That is, the fuel in this case does not burn out immediately, but decomposes into solid residues with the release of pyrolysis gases. Further, these gases are mixed with oxygen, as a result of which both the gas itself and the remaining fuel are almost completely burned.

Important! It turns out that the combustion of fuel using this technology occurs in two stages. And if the separation of solid residues is carried out at the first stage, then it is possible to obtain a finished production of coke. However, the main heating occurs as a result of mixing pyrolysis gases with air, which is already observed at the second stage.

How does a pyrolysis oven work?

In order to better understand what such structures are, it is necessary to consider in detail the principle of a pyrolysis furnace. The high efficiency and economy of such heating devices are due to design features. Pyrolysis furnaces of the classical type have the following principle of operation:

In the body of the device there is a built-in firebox in which firewood is laid. The peculiarity of the furnace design is that the air flow here is very small. To do this, the firebox has a tight door that closes hermetically, as well as a supply and exhaust fan.
Firewood is laid in the firebox, which can be ignited either with a built-in burner or manually.

Some time is allotted for the firewood to flare up properly, after which air access is limited to the furnace.
In view of lack of oxygen, charring of firewood occurs, as a result of which gas is released entering the other combustion chamber through a special air duct. Here, the incoming gas is mixed with air, during the combustion of which most of the heat is released.

The video shows the design of the pyrolysis furnace and the principle of its operation.

Important! There are various types of construction of the second chamber. It may involve the presence of a separate supply and exhaust fan or be serviced by a furnace fan. It is also possible to operate on natural draft. In this case, the chimney system assumes the presence of several sealed dampers.

For the extraction of coal in industrial and artisanal furnaces, there is a rotary retort. It most often has a round shape.
If the coal has not been removed from the furnace, then it is also burned, maintaining a constant temperature in the first furnace. As a result, there is practically no ash left in the furnace, the loaded fuel is completely burned, which is one of the key features of this type of furnace.

Important! The pyrolysis combustion oven needs ash removal approximately once a week.

Advantages and disadvantages

The pyrolysis plant has a number of advantages, among which are the following:

Due to the complete combustion of firewood and the duration of work on one load, high efficiency of such stoves is ensured.
It heats up fairly quickly, providing effective heating of the room.
High efficiency of about 85% (higher than conventional furnaces).
Environmental Safety. The combustion products of such furnaces contain a small amount of dirty and harmful substances, which is why such installations are called smokeless.
Ability to work in a wide range of thermal power (5-100%).
Any heating circuit can be connected to installations of this type.
Pyrolysis ovens require minimal supervision during their operation. Fuel is loaded about once a day, and ash is unloaded about once a week without stopping the operation of the unit.
You can load various fuels into the furnace. It can be either solid or liquid. This includes raw firewood, and various garbage (even tires from a car). Special designs have also been developed for burning used engine oil.

There are disadvantages to such long-burning designs, but they are significantly less than the advantages:

They differ in very large dimensions.

A special platform is needed to place the fuel.
Since some impurities and odors are emitted during the operation of the furnace, the room where it will be installed needs ventilation.
Since the exhaust gases are at a low temperature, this leads to the accumulation of condensate. It is present in the chimney and outlet channel. To collect it, a built-in drive is often provided.

Advice! Due to the formation of condensate, it is necessary to provide for a larger diameter of both the chimney itself and the outlet pipe, which must be insulated from the street. This will prevent it from freezing due to a decrease in ambient temperature.

To provide the heating system with really high-quality work, it is necessary to install a fan in the oven, and provide a pump for the heating system itself. All this leads to the dependence of the design on the mains.

How to make a low power pyrolysis oven?

Despite the relative complexity of the design of pyrolysis furnaces, you can make such a heater yourself. Quite widespread are the options for manufacturing a unit from a brick or from a gas cylinder, however, the sheet metal construction has the greatest aesthetics and efficiency in work.

Pyrolysis furnaces with low power (up to 25 kW) are great for country houses, garages, greenhouses and any premises that do not exceed 100 m 2 in area. This design differs from a conventional pyrolysis furnace in the following features:

Not connected to the heating system.
There is no need to install a smoke exhauster, since in this case the combustion chamber is simply located above the gasification chamber. Thus, natural traction is created.
Due to the fact that the design is not automated, it is necessary to periodically adjust the combustion mode and monitor the operation of the equipment.

Advice! For the efficient operation of such a furnace, the following conditions must be met: air is supplied to the gasification chamber in limited quantities. For this, a special damper is used. The chamber in which the gas is burned must be equipped with an air duct, through which the required amount of fresh air will be supplied to the system.

Instructions for the manufacture of such a furnace includes several steps:

According to the scheme, the body of the structure is welded from heat-resistant steel, in which holes are provided for the ash pan door and the combustion chamber. In this case, the combustion chamber should be located above the ash pan, separated from it by a cast-iron grate.

Important! The air supply to the combustion chamber is regulated by means of the ash pan door.

The gas combustion chamber is located exactly above the furnace. Between them is a cut-off plate, which is made of heat-resistant steel. The furnace must have a special channel through which air will be supplied with the possibility of blocking it through a special damper.
For the manufacture of doors, the same sheet metal is used, which is additionally reinforced with a corner. Doors must be locked.

Advice! If desired, you can buy doors made of cast iron in the store. They are available in various sizes.

The inside of the furnace chamber should be lined with fireclay bricks, which will not only protect the structure from burning out, but also contribute to better heat distribution.

Advice! You can also line the oven with brick, which will eliminate the possibility of burns.

The chimney should be made from a heat-insulated pipe. To regulate the draft in the design, a gate is provided.

Conclusion

The pyrolysis furnace is very popular due to a number of advantages over analogues. The main ones are economy, high efficiency and the ability to use any type of fuel. If desired, and the availability of drawings, you can make such a furnace yourself.

Brick ovens have been popular since ancient times. At first it may seem that this is one of the simplest designs for heating a private house. However, in the case of prolonged daily use, a large number of different nuances may occur. For example, for the construction of a stove, a special foundation will be needed, which is made by professionals. Such services are not cheap, as a result, it turns out that a brick stove becomes a costly and troublesome business. A pyrolysis oven can be a good substitute, some elements of which can be easily made by hand.

Brick ovens are popular due to their durability.

Constructions of this type are quite often used in country and private houses, in summer cottages, that is, in places where there is no central gas main and heating.

Some people want to build one that will work on the principle of pyrolysis. It is quite simple to build such a structure if you know the manufacturing technology.

This device can work not cyclically, but regularly. You only need to add fuel a few times a day.

Advantages and disadvantages of the pyrolysis oven

The advantages of this type of design include the following:

Maintaining the set temperature of the heat carrier for a long period. This can be achieved by increasing the volume of the chamber to be loaded.
The minimum content of harmful substances at the time of fuel combustion. With this design, you can maintain a healthy and comfortable atmosphere in the premises, if it is correctly installed.
In such a stove, various wastes can be burned, such as rubber, fiberboard or plastic. All such materials can be used as fuel. However, this does not mean that the fuel should consist exclusively of waste. Waste should be 1/3 of all fuel.

This stove also has some drawbacks. The most significant of them are the following:

fuel requirements. All fuel must be dry. Wet wood should not be used, since with wet fuel the pyrolysis process will not be possible. Instead of receiving thermal energy, it will be lost with steam and combustion products.
Relatively large sizes. This is a disadvantage if the stove is planned to be located in a small room.
Comparative energy dependence. A fan that will maintain thrust will not be able to constantly work.
The stove needs constant care. It will be necessary to add firewood in a timely manner and remember that it is necessary to close the dampers after the firebox. Before the next firebox, be sure to select coal from the stove, and then perform all the steps again.

Before performing installation work, you will need to draw up a diagram of the manufactured structure and perform the necessary calculations. The easiest way is to take a ready-made scheme, for example, based on Belyaev's calculations. It is calculated for a brick structure with a power of less than 40 kW.

The perimeter of the furnace is laid out from ceramic bricks. To arrange internal partitions, you will need to use fireclay bricks. You can use the design after it is assembled and the fan is connected. It is imperative to take into account the burning time for all materials in order to add fuel on time. Pressed briquettes can be used as materials for heating. After starting the pyrolysis oven, it is important to determine its efficiency. This is easy to do: you just need to smell the smoke that comes out of the chimney. If there are no carbon monoxide impurities in it, then this means that the efficiency is at a high level.

In the process of building a pyrolysis stove with your own hands, you must comply with all existing fire safety rules. If any of the rules is violated, then the design can cause not only material damage, but also a threat to the health of residents and visitors to a private house in which a do-it-yourself brick pyrolysis oven is installed. The design is recommended to be placed in a separate non-residential room. For the stove, you need to arrange a base of brick or concrete screed. The combustion chambers must be additionally protected with a sheet of thick metal.

The fuel for the pyrolysis oven must be dry.

One of the significant advantages of such a stove is that in this case both water and air can be used as a heat carrier. Consequently, in winter, the pipes will be protected from freezing, and therefore it will not be necessary to drain the system.

A boiler of this type must be located at a distance of 20 cm from the walls. The room with the furnace must be equipped with additional ventilation.

To build a stove with your own hands, you will need to prepare the following elements:

Ceramic brick (approximately 400 pieces).
Chamotte brick (about 100 pieces).
Steel sheet with dimensions of 6x1.5 m. The thickness of the product must be more than 4 mm.
Cast iron grates (3 pcs).
High power fan. The minimum possible power is 300 watts.
Lever temperature controller.
The door blew.
Furnace door.
Electric apparatus for welding.
Electric drill.
Several grinders with different circle diameters.
Pipes of various diameters.
Proftruba.
Electrodes for electric welding.
Temperature sensor.

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Do-it-yourself pyrolysis oven: manufacturing process

It is quite difficult to build such a furnace with your own hands from brick. If a complete set of necessary technical support is available, there will be a large number of nuances in connection with which you need to get advice from a specialist with relevant work experience.

You will need to work with a high combustion temperature and comply with existing sealing requirements, which is quite difficult to do yourself. You should be aware that such a design does not need to be connected to the heating system, since this device will simply heat the air in the rooms.

To enhance the moment of heat transfer from the inside, it is necessary to line the stove with special fireclay bricks; from the outside, the structure is lined with refractory bricks.

To build such a boiler, you will need not only to have the skills to work with a grinder and measurement tools, but also to be able to weld metal.

It should be understood that the manufacture of a pyrolysis stove consists not only in laying bricks, but also in installing or constructing a boiler, which is the main element of the entire fixture.

The easiest way is to purchase a ready-made boiler, and then overlay it with bricks. Thus, it is possible to obtain a brick structure, which only needs to be installed and connected.

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How to install the boiler correctly?

It is worth remembering that the boiler is a fairly large piece of equipment that weighs a lot. Therefore, you will definitely need to make a base for the structure.

If a private house has a simple floor base without reinforcement, that is, there is no concrete slab under your feet, then you need to dig a hole 20-30 cm deep, and then pour concrete mortar into it. In some cases, the foundation is laid out with bricks, but here everything depends on the personal preferences of the owner of a private house.

The concrete base is a solid structure that can easily support the weight of the stove, while the foundation will not deform for a long period.

The first step is to decide where it is best to place the stove. You need to choose only from non-residential premises. Despite the latest technology, the pyrolysis stove will produce toxic substances when burned. If there is a depressurization of the structure, then big problems can arise.

In the process of laying, you need to use a special solution of sand and clay. It is not allowed to use a standard cement mixture, since at high temperatures it can form cracks and pass gases and combustion products.

Ordinary building bricks will be used to zero out the base. After that, only refractory ceramic material may be used.

Solid fuel heating equipment will always be in demand. There are places where gas may never appear. In some settlements, gas supply is planned for the next 10-15 years. Some people just like to heat with wood, while others use wood-burning stoves to heat baths. Pyrolysis oven will be an ideal option for space heating for any purpose. It can be made of metal or brick. Our review-instruction will tell about the manufacturing process.

How a pyrolysis oven works

To begin with, we will consider the principle of operation of the pyrolysis furnace. Traditional wood stoves use the principle of direct combustion of fuel. The firewood loaded into the combustion chamber (furnace) is set on fire and begins to emit thermal energy. This energy heats the walls of the unit, after which it penetrates into the heated rooms. The products of combustion immediately fly into the chimney. At the same time, another 10-15% of the heat flies there.

The disadvantage of a conventional furnace is the high heat loss. The combustion products fly into the chimney hot, they are full of heat that can be collected and sent for heating. In the simplest case, users lengthen the pipe, making the horizontal section longer - it runs through the entire room. Thus, heat losses are reduced.

Pyrolysis furnaces are arranged somewhat differently. They have two chambers - in the first, the combustion of fuel is carried out, in the second, afterburning of the combustion products is carried out. In the process of burning wood, pyrolysis products are released - these are combustible gases that burn at high temperatures. Their combustion requires secondary air - it enters the afterburner, mixes with pyrolysis gases, as a result of which this mixture ignites.

Long-burning pyrolysis ovens are the best equipment for your home, cottage or bath.

Advantages of pyrolysis ovens:

Higher efficiency compared to traditional ovens - the pyrolysis process allows a higher amount of heat to be extracted from the same amount of wood.
The ability to control the combustion process - by adjusting the draft or air supply through the blower (and secondary air supply), you can set a certain intensity of combustion, setting the desired temperature.
Long burning - pyrolysis furnaces are usually equipped with large fireboxes, which can hold a significant amount of firewood. The duration of burning also provides the ability to control this process (the adjustment range is from 10 to 100%, depending on the design).
Fuel economy - with not the most complex device, pyrolysis ovens save up to 10-15% of firewood.
A wide range of applications - from baths to residential buildings.

The main types of furnaces

Pyrolysis furnaces for heating houses and baths are divided into two broad categories. The first category includes metal stoves made from sheet metal or old gas cylinders. The second category includes brick units, more bulky, but also more efficient in operation. Plus metal furnaces - ease of assembly. Plus brick stoves - long-term preservation of heat and its soft return.

How to make a pyrolysis oven with your own hands

To begin with, we will deal with the manufacturing process of a simple pyrolysis potbelly stove. Let's take the following drawing as a basis:

This oven is made according to the following scheme:

A couple of metal tubes for air supply - and an ordinary wood-burning stove turns into a pyrolysis stove.

How to make a metal stove

A portable pyrolysis oven with your own hands is very simple. Make sure of this by reading the drawings in our review. To assemble it, you will need sheet metal. We recommend choosing sheets with a thickness of 3-4 mm, which is necessary to extend the life of the unit. Thin iron will quickly burn out, the efficiency of the stove will begin to fall. A year or two of such operation - and it can be thrown into a landfill.

By the way, if you need a pyrolysis oven for a bath, pay attention to the following diagram - here we see an enlarged combustion chamber, all the same smoke circuits, only a heater is located in the very top part.

The design of the stove must be finalized so that its firebox goes into the next room, and not into the steam room (it protrudes forward).

When starting to assemble a bath or pyrolysis oven with your own hands, prepare sheets of iron and mark them in accordance with our original scheme. The furnace body consists of six metal plates, two more form smoke circulations. You also need to assemble the grate - to solve this problem, use fittings with a diameter of 12-15 mm. The grate is fixed at a distance of 80 mm from the bottom of the furnace by welding.

The most difficult task is to prepare the doors. Cut holes in the sheet intended for the front wall, save the cut pieces. Weld along the perimeter of these pieces pieces of sheet metal 2 cm wide, welding them from the outside. As a result, we get tight-closing doors. They will have to be equipped with loops and simple hooks for fixing.

If you don’t feel like messing with homemade doors, buy ready-made doors for making wood stoves.

Pyrolysis furnaces for heating a house should give off maximum heat. That's what smokers are for. Mount them according to the diagram above. Now it remains to make holes in the back wall and weld pipes for supplying hot air into them. Final assembly steps:

Welding a piece of pipe with a diameter of 100 mm into the top cover - a chimney will be connected to it.
Welding door hinges to the body.
Preparing the legs - make them from segments of an inch metal pipe.

Our homemade wood-fired pyrolysis oven is ready. It turned out to be compact - thereby ensuring the ease of its transportation from place to place. Install it on a non-combustible base, connect the chimney and run.

The bath model is made as follows. Lengthen the firebox by moving the doors forward, and leave the flue pipes the same. In the upper part, make a container for the heater - stones are laid here that retain and give off heat to the steam room. The stove is ready - now mount it in the bath and proceed to the bath procedures.

How to make a brick oven

You will also need an ordering that is suitable in size and power. Finding a normal order on the Internet is a whole problem; only traditional stoves are in the public domain. We recommend ordering its development from specialists or experienced people.

The metal oven is easy to assemble. With the right iron, cutting and assembling it will take a maximum of several hours. But a brick pyrolysis oven is not easy to manufacture. You will need:

Refractory brick for laying out the heating unit.
Special refractory cement mixture - it must withstand up to +1500 degrees.
Experience in bricklaying - if not, seek help from more experienced people.

A brick pyrolysis oven is an analogue of a conventional metal stove. Only in size it turns out to be large and complex. The larger the brick, the softer and better the heat transfer. There are no special design features here. Firewood is burned in the main combustion chamber (furnace). The resulting pyrolysis products are sent to the afterburner. For its operation, holes for supplying secondary air are provided in the design of the furnace. They are equipped with doors, adjusting their clearance allows you to adjust the intensity of combustion.

Pyrolysis units with lower combustion are in some demand. Firewood burns / smolders in the main combustion chamber, pyrolysis products are drawn down through the grate down into the afterburning chamber. Secondary air is also supplied here, which causes intense combustion. Traction is realized naturally or artificially. In the first case, the stoves are equipped with efficient chimneys, and in the second case, blowers are placed here.

The inner part of the furnace, where combustion and pyrolysis reaction take place, are made of fireclay bricks. It withstands heating up to +1000 degrees and more, without cracking or bursting from the heat. All other layers are made of ordinary red brick. The chimney can be brick or metal. Doors are purchased in specialized stores. The operation of a brick pyrolysis stove will delight you with long-term burning and pleasant warmth, which persists even after it is attenuated.

Stove modernization

Almost any pyrolysis oven can be turned into a boiler for water heating. For this, ready-made or home-made (from metal pipes) heat exchangers are built in. Radiators are installed in the rooms, water is poured into the system - full heating is ready.

For these purposes, it is best to adapt a pyrolysis oven with a blower fan - equip it with an external control unit that monitors the temperature and controls the operation of the fan.

Hobs and built-in ovens - that's what else you can equip any oven. The energy of pyrolysis combustion is enough not only for heating, but also for cooking. Hobs and oven boxes are available from specialist retailers. The oven can be made independently from sheet iron. As for the hobs, they are made of cast iron - you can’t do this yourself.

Video

When choosing a method of heating and hot water at home, people pay special attention to its cost and practicality, as this will affect regular monthly expenses for many years. Of course, each solution has its pros and cons. The advantages of pyrolysis ovens over traditional solid fuel boilers include low environmental impact, lower fuel consumption and lower maintenance costs.

Do-it-yourself pyrolysis oven at no extra cost

History of technology

Heating organic materials in the absence of oxygen leads to chemical and physical changes in them. In the past, these phenomena were used to produce charcoal. The most primitive way looked like this: the wood was covered with a clay mound and heated in the relative absence of air. With the help of this technology, coal production peaked in the 11th-12th centuries.

The serious consequences of such reforestation are now being felt in parts of Africa and Asia. Despite its apparent simplicity, this method is not environmentally friendly. As a result of the pyrolysis of wood, resins are released, which are volatile products with a large molecular weight. They condense easily at normal ambient temperatures. But despite this, solid residue (coal) has traditionally been a valuable fuel for primitive agrarian communities, due to such qualities:

high carbon content compared to the original wood;
low sulfur content.

Earlier steel production, including successful attempts to cast cannons from it, was based on the reduction of iron oxide with carbon in coal. A similar technology using charcoal, based on the processing of eucalyptus, is also practiced in modern Brazil as economically justified.

Pyrolysis oven is very economical to use

Pyrolysis has found wide industrial application in coking operations. Furnace designs and reaction conditions in them have changed depending on demand and prices for end products. In mid-19th century Europe, carbonization of coal was used to produce gas to heat and light houses. At that time, only the royal palaces could enjoy such innovations. Domestic use of pyrolysis gases ceased with the development of transportation of natural hydrocarbons.

How to make a pyrolysis oven with your own hands:

During World War II, many cars and trucks were converted to wood gas generated in mobile units placed on vehicles. Their productivity was low due to the low energy density of the gas, which, as a rule, contained a large amount of nitrogen and other non-combustible compounds.

The durability of engines using such fuel was not great and was reduced primarily due to fly ash entering the cylinders along with wood gas. But despite these shortcomings, the use of such machines was justified by the shortage of fuel. After the end of the war, these installations were forgotten until the present day.

Now the problem of obtaining fuel from biomass instead of fossil fuel is again relevant.

Modern technologies make it possible to obtain, using pyrolysis, high-quality purified gas suitable for heating from waste wood and agriculture.

The principle of operation of furnaces

Pyrolysis of organic raw materials is the heating of biomass to a high temperature without air access.

Detailed structure of pyrolysis oven

Under such conditions, the fuel is converted into a mixture of three types:

coal (solid);
organic gases (gaseous);
oils (liquids).

Depending on fluctuations in temperature and the speed of ongoing processes, the percentage of charcoal, gas and oils varies.

The advantages of such wood burning in comparison with traditional ones:

greater efficiency with the same amount of raw materials;
insignificant negative impact on the environment (for example, for such a parameter as CO2);
small formation of solid unburned particles (ash).

Most household pyrolysis stoves and boilers run on wood or briquettes. High-quality installations are able to function on mixed raw materials (cuttings, bark, shavings, sawdust, logs). Regardless of the type of fuel, three processes take place in them:

Drying and heating of wood material in the bunker with the release of gaseous components.
Combustion of gaseous products.
Combustion of solid components (charcoal).

Pyrolysis oven is perfect for giving

Each of these stages requires different conditions, so the correct distribution of temperature and other factors that affect the chemistry of the processes is the basis for the efficient operation of the plant. The wood is dried at temperatures below 200°C. The pyrolysis process starts around 300°C. At this temperature, cellulose, as the main component of wood, is destroyed with the formation of light compounds. Closer to the nozzle, the temperature in the pyrolysis combustion furnace rises to 200-700°C. There, the biomass is freed from volatile compounds and converted into charcoal.

The emitted gases are injected into the combustion chamber, where they get access to the required amount of air for combustion, burn out and release heat. Charcoal is burned on a grate. The unburned residues fall into the ash collector.

More about pyrolysis oven:

Fuel Requirements

Pyrolysis ovens for the home, working on briquettes, can be fully automated and the comfort of their maintenance in this case is comparable to gas ones. The fuel for them is waste compressed under high pressure without chemical binders. This technology makes it possible to produce relatively dry briquettes with a high calorific value. Their properties, however, may be different.

Pyrolysis furnaces and boilers operate on a wide variety of fuels

Most of them are not destroyed during combustion in the furnace, while others can only be used in a mixture with lumpy wood or brown coal. Small briquettes are fed by screw conveyors and therefore they are used in automated systems, larger briquettes are only suitable for manually operated long burning pyrolysis ovens. Wood pellets intended for automatic installations are obtained in the same way as conventional briquettes. Their only significant difference is the size. White softwood pellets without bark are considered the highest quality.

For wood-fired pyrolysis ovens, the size and type of raw materials can significantly affect productivity - a large surface area of \u200b\u200bwood causes a greater amount of releasing gas per unit time. Hard rocks are gasified more slowly.

Service Features

The important point is to keep the fuel always dry - the recommended humidity is 12-20%. This is necessary not only for combustion efficiency, but also affects the life of the furnace. Water vapor and some gases released during drying form tars and acids during condensation, which corrode the equipment. Due to the fact that the calorific value of wood decreases with humidity, its consumption increases. Burning raw fuel can cut the life of stoves in half.

Pyrolysis furnace does not require constant filling with fuel

Pyrolysis combustion produces less ash than conventional combustion. In practice, this means that gasification furnaces require less care for the removal of heavy bottom ash. But fly ash is capable of depositing in significant quantities on the ceramic fittings of the combustion chamber, leaving less and less space for combustion. The latter can threaten overheating and equipment failure. Therefore, at least once a year, it is necessary to clean the fan blades and chimneys.

Almost all types of pyrolysis ovens need such maintenance.

In addition to high efficiency, saving time on preparing firewood and kindling, pyrolysis ovens, compared to conventional ones, have another serious advantage - the possibility of stepless power adjustment. This property, together with economy, environmental friendliness and automation of combustion processes, makes pyrolysis furnaces the best alternative to traditional heating methods for country houses.

How to make a pyrolysis miracle oven:

From the author: hello dear readers! A lot of owners of country dwellings, whether it be a small country house or a large cottage with outbuildings, are interested in the question of how a pyrolysis oven is made with their own hands.

I must say that solid fuel equipment is generally very in demand for many years. It is quite efficient, environmentally friendly, fuel production is usually not difficult, and from an aesthetic point of view there is an advantage - after all, many people like to watch dancing flames. Of course, this is best done while sitting by a large stove or fireplace. But small ovens are no less popular.

For example, they are very convenient to use where there is no heating: in sheds and other outbuildings, in the garage and even on the street. Such a heating structure can be equipped with a hob, and then you can cook delicious meals in the fresh air.

Of course, not every homemade stove is highly effective. Some of them are, in fact, just a fire limited on all sides. This approach also has the right to life, but today we will talk about a different kind of design - namely, about pyrolysis.

The principle of operation of the furnace

The difference between this design and a conventional stove is the long-term combustion of fuel, which leads to a much higher level of heat transfer. In simple solid fuel heating structures, the process occurs as follows: firewood burns, the walls of the structure heat up from the flame, and heat flows from them into the room. The smoke generated from the burning fuel goes directly to the street through the chimney.

But the fact is that it is in these combustion products that a very large amount of thermal energy is contained, which, in fact, is blown by the wind. If the smoke did not fly away so quickly, then due to it a lot of heat would get into the room.

Some homeowners are aware of this factor and lay the chimney pipe through the entire room, dividing it as long as possible. Of course, in doing so, they receive some more heat. But most of it still continues to leave. That is why simple solid fuel stoves require constant “feeding” - firewood is laid very often.

As for pyrolysis equipment, a different approach is practiced here. The furnaces are equipped with two chambers. Fuel is loaded into one of them - usually firewood -, and there it burns. At the same time, pyrolysis products are produced - that is, gases that can burn at high temperatures. They enter the second chamber, and secondary air, which is necessary for ignition, also comes there. Which, in fact, is happening.

Naturally, in the process of combustion of pyrolysis products, a large amount of heat is generated, which also works to heat the room, as well as the thermal energy that comes out during direct combustion of the fuel. Thus, these furnaces have several advantages:

high efficiency, compared to conventional ovens. The efficiency of pyrolysis structures can reach up to 95%, which is very good;
long burning process. This is due to both the high heat output and the fact that the main chamber is made quite large. Therefore, quite a lot of firewood is placed in the oven. This is very convenient from the point of view of operation - as a rule, fuel is loaded only once a day;
the ability to control the process of burning fuel. You can control the supply of both primary and secondary air. The intensity of burning firewood and pyrolysis products depends on this. Thus, you can set the temperature mode of heating depending on your current needs;
saving fuel resources. Since firewood in this case gives off the maximum amount of heat, they are required less than for a conventional stove;
wide scope. Pyrolysis ovens can be used both in residential and commercial premises, as well as in a bathhouse and on the street;
ease of manufacture. You can easily build the structure yourself. Of course, the simplicity varies with the method of manufacture. For example, to make a metal furnace easier than light, you will not need any special skills, and this process will take a little time. But a brick pyrolysis structure is made longer and physically heavier - at least due to the weight of the blocks. But still, any of these varieties is available for self-production, which will be discussed below.

As a drawback of the structure, one can name, perhaps, the presence of certain requirements for fuel quality. Wet firewood will definitely not be in demand here, since water vapor will nullify the entire efficiency of the stove - they will actively interfere with the processing of emitted gases. Therefore, the initial selection of high-quality fuel and its proper storage are also important.

Now you know the general principle of the furnace, and you can also decide on the need for it. Of course, you can purchase the design in the store. But why, if it is quite possible to do it yourself, at the same time having trained in working with metal or brick. Let's start with the first option.

metal stove

A metal oven is much easier to make than a brick one. True, its effectiveness is lower, but in most cases this is quite enough. In general, the design resembles with a slightly complicated smoke removal. You can refer, for example, to this drawing:

A source: repair-system.ru

As you can see, the combustion products go in a "snake". If you provide secondary air access to the first smoke circuit, then you will get the same pyrolysis process.

To make a metal pyrolysis stove, you will need:

steel. Prepare sheets with a thickness of at least three millimeters. If the material is thinner, it will burn out to holes very quickly, and you will have to start the whole process again. In principle, instead of steel, you can take what is often found in private households: a metal barrel or a gas cylinder. If you decide to use the latter option, please note that the container must first be prepared. In any cylinder there are gas residues. Even if there are few of them, it can still provoke a fire during operation - one spark is enough. Therefore, be sure to first fill the bottle with water through the hole by unscrewing the shut-off valve, and then leave it outside. Empty the container at the end of the day. The smell will not be the most pleasant, so do it somewhere away from living quarters. Only after the flushing procedure can the gas cylinder be used for the production of a pyrolysis oven;
welding machine. If you don't know how to work with him - it's okay, there will just be a reason to learn. At the same time, stock up on protective equipment: at least goggles and gloves. Welding work has an increased level of danger, so be sure to take care to prevent injury;
marking tools. You will definitely need a flexible tape measure and a marker. It is also advisable to use the building level to avoid distortions;
various small tools. Pliers, a hammer and other improvised tools that may be needed in any such work;
doors and grate. The easiest solution is to purchase these items at some forge or shop. The advantage of this approach is the aesthetic appearance of the doors. But you can do it all yourself to avoid unnecessary costs. Make the doors from the same sheets of steel that will go to the stove itself, or from pieces of metal cut from the body of the gas cylinder (if you decide to use it to make the structure. The grate can be made from steel strips or thick wire, to which reinforcing bars are soldered with small gaps between each other.

So, after you have prepared everything you need, you can get to work. Take the steel sheets, mark them according to the diagram above, and then cut 8 plates along it: six for the furnace body and two for the formation of chimneys.

Now build a grate and doors if you decide not to buy them. How to do the first one has already been written above. As for the doors, you need to weld hinges, sides and a place to fix the valve on them.

Mount the flue pipes inside the furnace body. Make several holes in the back wall and weld tubes to them. Then weld another pipe to the top cover, the diameter of which is 10 centimeters - it is needed for the subsequent connection of the chimney.

Finally, weld the doors with hinges to the places where they should be located. At the same time, be careful and strictly follow the markings so that there are no distortions. The last step is to install the legs. You can make them from steel angles or something similar.

There is another version of the metal pyrolysis stove, which is used in the bath. The base is done in the same way, but the firebox must be lengthened by moving the doors forward. The size and number of smoke turns do not change. You also need to make a stone. To do this, weld a container to the top of the body. It will be possible to pour stones into it, which will qualitatively retain the heat coming from the stove, and then give it to the steam room.

The metal pyrolysis furnace is quite compact and light. You can easily move it from room to room. Mobility, ease of installation and high efficiency make this design almost indispensable for any private household.

brick stove

A pyrolysis brick oven has even higher efficiency than a metal one. This is due to the excellent characteristics of the brick. Blocks are able to retain heat qualitatively, and then give it to the surrounding air. Thus, the heating of the room is softer and longer.

The disadvantages of such a stove include the complexity of its manufacture. As mentioned above, this will take more time and effort than in the case of a metal structure. In addition, for work it would be nice to have some experience in the construction of brickwork. However, it is never too late to learn, and the creation just might give you the necessary skills, which are likely to come in handy in the future.

As for materials, their selection also needs to be approached carefully. You can not take the first brick that comes across, because here we are talking about prolonged exposure to high temperatures. For example, a firebox that is in direct contact with an open flame should be made exclusively from fireclay bricks. These are refractory blocks that perfectly resist high temperatures and at the same time conduct heat well.

As for the rest of the structure, you need to take ordinary ceramic red bricks for them. This material has good heat-capacity characteristics, therefore it is suitable for the construction of the hull as well as possible.

The process of building a brick pyrolysis furnace is the same as in the case of a metal one: a chamber is made for burning fuel and several smoke turns. Then the doors, plugs and chimney are mounted. The finished design is quite large. This must be taken into account when planning its placement.

In addition, do not forget that bricks have considerable weight. Therefore, it is desirable to place a solid board or something similar under the structure as a base.

In the process of laying bricks, it is important to observe order. In each row, the blocks are stacked in a certain way: somewhere on the "bed", somewhere on the edge. This is necessary in order for the structure to be durable. Unfortunately, there is no single ordering scheme for any furnace, so it’s better not to look for it on the Internet, but to contact a specialized organization for compilation. This approach will give you confidence that everything will be done correctly.

To get even more knowledge on how to make a pyrolysis oven, watch the video:

Despite the seemingly complicated principle of operation, in fact, a long-burning stove is a fairly simple structure. It is enough to understand in detail the basics of its creation - and you will surely cope with this matter easily and simply. Good luck!