If a few decades agoThe only heating option for many was coal and wood, but today there is gas. However, this fossil fuel is sometimes not possible. For example, in some places in the private sector and holiday villages there is no gas pipeline. In order not to resort to coal heating, the owners build pyrolysis furnaces with their own hands. Let's understand what kind of equipment and what are its key features.
How the boiler works and what is pyrolysis
Do not confuse this equipment with a conventional solid fuel boiler. Although units can use similar fuel, such as coal, briquettes and firewood, their working principle is noticeably different.
In our case, we are dealing with the so-calleddry distillation. The combustion process takes place at a temperature of 200 to 800 degrees with a reduced amount of oxygen in the combustion chamber. As a result, dry wood is decomposed into solid residue and wood coke and the most important element is pyrolysis gas. The latter is mixed with oxygen and serves as a kind of activator of the combustion process. It is worth noting that today pyrolysis furnaces with their own hands are made quite often. This is due to their simple design and relatively easy assembly. By the way, the smoke that is formed during the combustion process does not contain harmful impurities. This can be achieved through the interaction of pyrolysis gas with carbon.
Top camera position
This design looks more profitable on the backgroundlower location of the camera. However, it is worth noting that such pyrolysis furnaces appeared relatively recently. The craftsmen constructed them with their own hands, after which they were sold in professional performance. Today, although they are in some demand, they have not yet received their due popularity. As for the merits, they are obvious. Such equipment operates on natural friction and is completely non-volatile. In addition, the inverted design adds some zest. The principle of operation of such a furnace is based on the fact that pyrolysis gas rises from the main chamber, located in the lower part of the furnace, into the upper chamber, where it mixes with oxygen. Through the lower opening in the furnace body, rarefied air enters, which, in combination with oxygen, provides an oxidation reaction. The actual combustion of the fuel is carried out in the lower chamber, then the coolant is heated. It is interesting that pyrolysis ovens of this type, made with their own hands, with proper performance, can work on one portion of fuel for up to 12-14 hours.
Little about the device
Необходимо понимать, что пиролизная печь состоит from two combustion chambers. Both are needed to sustain burning. One of the chambers into which fuel is loaded must be tightly closed to prevent oxygen from entering. Do not forget about this when designing the product. As a result, pyrolysis gas is formed, which rises into the afterburning chamber, where it mixes with secondary air. At the same time efficiency of burning increases, as well as heat transfer. The upper and lower chambers are separated by grate. One of the features of the process - overhead ventilation. In addition, the organization of forced traction is important. This will significantly reduce aerodynamic drag.
Do-it-yourself pyrolysis oven: about safety
If you are going to design a heatingequipment on its own, then we must understand that there are strict requirements for the quality of the air-fuel mixture and the actual safety of the furnace. For this simple reason, you will need at least a minimal experience in working with drawings and mastering any type of welding equipment. For accurate work, you will need to use electronics, and for the high quality of the body of the product - alloy steel. The electronic component is needed to control the process of pyrolysis. If this is not taken into account, then your pyrolysis oven by and large will turn into the most common stove. Well, now let's move on to the main stage, consider how to make equipment with your own hands. With proper skills and equipment, this will not be difficult.
Materials and Tools
Before the pyrolysis oven do it yourselfdesigned, it is necessary to acquire a set of tools, without which the work is impossible, as well as material. First of all, you need a welding machine and an electric drill. Also among the necessary tools should be present and angle grinder (angle grinder). In priority, it should be under a circle with a diameter of 125 mm, if this is not possible, then a 230 mm variant will do. Sheet metal will also be needed. Its thickness must be at least 4 mm and not more than 7.5 mm. In any case, the internal parts should be made of steel with a minimum thickness of 4 mm. In this case, the material for the body can be of a smaller thickness - 3 mm In addition, you will need to take a few packs of electrodes and about 10-15 pieces of refractory bricks for lining. At hand should be cutting and grinding wheels 230 and 125 mm, respectively. For the organization of electronics you need not so much. Fan and temperature sensor will be sufficient. For the separation of cameras used grate. Do not forget to purchase two doors.
Do-it-yourself pyrolysis oven: instruction and technology
Work begins with the calculations.If you do not have an engineering mindset, then you can contact a specialist for help. Usually the prices for such services are small. The very same scheme looks something like this:
- Welding work. Here you have to make a steel case and chamber (combustion and afterburning).
- The lining of the inner part of the fireclay (fire-resistant) brick.
- Making holes for supplying oxygen supply systems to the combustion chambers.
- Preparation of the combustion chamber window and door installation.
- Installing a water jacket.
- Installation of the fan in the discharge pipe.
According to this scheme, a pyrolysis furnace is madeby hands. Drawings in this case may or may not be present. The first option is preferable, since the accuracy of work and performance of the product will be better.
Start of work
It is necessary to understand that the basis of any boiler isIt is a fire chamber and the combustion chamber. The temperature there is quite serious, usually about 500-1000 degrees Celsius, therefore it is necessary to use a special metal. If there is none, any other will do, but then it’s better to double the walls. Cutting of the walls should be done using angle grinders according to the dimensions indicated on the drawings. The dimensions must be transferred as precisely as possible; for this, use a ruler and other measuring tools. After from the profiled pipe stiffeners are created. As you can see, for the time being, the pyrolysis furnace with your own hands, the drawings for which should be at your fingertips, is very simple. The main thing is to comply with the technology.
Making important knots
Any brick pyrolysis ovens, do it yourselfmanufactured, imply the presence of a door for the combustion chamber and ash compartment. They need to be done. To begin with, holes are drilled in the front wall, which are made according to the size of the door. In order to perform the work as accurately as possible, it is recommended to apply the marking with a sharp object and only then proceed to cutting.
Next you need to prepare a water tank.The tank should be made of stainless steel. It is imperative to weld a container that will not leak. If in doubt, it is better to contact the experts. Mini pyrolysis furnace is made by own hands in the same way as its large prototype. In any case, this is a complex of pipes, which forms between them a flow-through loop with a large heat transfer.
How to assemble a structure?
To reduce the complexity we recommendassemble directly on the job site. Take care of this in advance so as not to wear gravity. Before you begin, the foundation is laid, then the inner walls are placed along the perimeter, and the ash compartment is mounted on the bottom. The inner walls are joined by welding. In principle, the hull is ready, now it’s time to weld the combustion chambers, the heat exchanger and the grate along the guides. Stiffening ribs are vertically welded, and then external walls are mounted. Our pyrolysis furnace is almost done by hand. The scheme implies the presence of sand between the inner and outer walls. It is needed for heat accumulation and overheating protection.
We complete the design
After the sand is filled, mountedhermetic doors connected to the circuit with water. Today, many say that to make a pyrolysis boiler, whose power will be less than 15 kW, is impractical. In principle, the metal structure is complete. And a simple pyrolysis furnace with their own hands almost made. All that's left is to do some work with bricks. What is a refractory solution made for? By the way, there are a huge number of cooking recipes, which one to choose is up to you. You need to know that fireclay bricks are suitable for lining the firebox. However, in this case it is not necessary to count on the work of the product for more than one season. As you can see, pyrolysis furnaces are not made very quickly and not as easy as we would like, but it can be done.
And the final touches.First, you need to make a heat exchanger from fireclay bricks. It should be divided into two chambers. Then in the free position, the installation of grates. It should be understood that when heated, they expand and fill the gap left. At the very end, the doors are inserted, the valves and levers are adjusted. It is necessary to properly adjust the fan, which is necessary to overcome the aerodynamic drag. For example, a camp pyrolysis furnace is made about the same way. But its design implies significantly smaller dimensions and weight due to the lack of lining and thick steel. Nevertheless, in nature, such equipment works quite effectively.
