Boilers of upper combustion: what is it, the types, the principle of operation

The problem of heating is one of the most difficult tasks that owners of country houses have to solve. Ignore the organization of the heating system does not work - you can not live in an unheated room in winter. Rapid temperature changes will quickly render the entire finish unfit. Also, the service life of the building is significantly reduced. Optimal solution of heating issues - the organization of a heating system for water heating, where the pipes and radiators will circulate the coolant. The main problem is to choose a thermal generator or a boiler that converts external sources of energy into heat. Based on the characteristics of the climate, as well as the degree of availability of energy resources, more and more popular today are aggregates of long-term combustion, in particular, boilers for upper combustion with solid fuel. What is this, we consider below.

What is good for a long burning boiler?

Traditionally, private houses are equipped with gas boilers. However, not all locations have highways with such fuel. In addition, to connect an individual gas line in the presence of a highway will require significant costs.

If you add to these costs mandatory procedures for approvals, project drafts in which all requirements are fully met, then the installation process of such a boiler will only scare off the owners. Especially if there are worthy alternative solutions.

It would seem that if there is no possibility to install a gas boiler, then it is always possible to purchase an electric boiler. The choice of such equipment is quite large. Boilers have a high efficiency, they are easy to adjust, the number of control systems, and also equipped with an automatic control system. However, all these advantages become disadvantages when the owners begin to recall the cost of electricity. An ordinary family will easily be ruined by such heating. In addition, in the villages that are remote from the regional and urban centers, the voltage is not particularly high - in the network, you can observe strong fluctuations. And the owner of the electric boiler puts itself in dependence on the quality and stability of the current supply.

Against the backdrop of constant technological progress, the traditional method of heating housing with firewood and other solid fuels has gone into the shadows. But firewood is a good source of energy, in addition - renewable. There is no shortage of wood for heating. You can use firewood, which the owners of houses procure independently, or buy them. Also, many woodworking enterprises sell waste products.

But the oven is not in all houses. Yes, it is effective and at the expense of its design it keeps the heat well. It is enough to flood the stove to provide the house with heat for a day. But there is one nuance: what about the circulation of the coolant along the contours of the heating system? After all, if you just keep burning in the oven, then it will be a big fuel consumption. This problem can be solved with solid fuel boilers of upper combustion.

Due to the special design of this device, based on the physical and chemical properties of solid fuel species, it is possible to load firewood once for 12-15 hours. Some models can work and more on the same load.

The advantage of long-burning boilers with upper combustion is that besides wood, a number of other materials can be used. Apply all that burns - it can be briquettes from waste woodworking industries, as well as coal or peat. Also now, as a source of energy, so-called Euro-rods became very popular.

Operating principle

How conventional solid fuel furnaces work is known to everyone. Fuel is poured into the furnace - briquettes or coal. A lower airflow chamber is provided from the lower chamber, which is necessary for the process. The level of burning intensity in this case is limited only by the amount of oxygen.

This is an ordinary fire, which is enclosed in a metal casing, which requires a constant addition of fuel. The combustion products are directly discharged into the chimney - this system has many turns and labyrinths. This improves heat transfer and leads to an increase in efficiency. However, this does not increase the overall energy output. Thermal decomposition of wood is a quick process, after which a lot of waste remains, and untapped energy is released into the atmosphere. This energy is obtained due to the special characteristics of the tree, which, in turn, are due to the biochemical composition. When the wood heats up, it not only oxidizes to coal, but also releases carbon dioxide and carbon monoxide. The influence of high temperatures always leads to the synthesis of volatile compounds based on hydrocarbons. These compounds have a rather complex chemical formula. By themselves, gases are excellent fuel, which in an ordinary furnace goes nowhere.

Pyrolysis

The process when wood decomposes into gases is called pyrolysis. Combustion temperatures, as well as heat transfer, are much higher here than in conventional combustion. At the same time, the oxidation processes of the wood are so deep that after pyrolysis there is practically no waste left. Only steam and carbon dioxide are released into the atmosphere.

Hence, it is much more rational to use wood fuel, while minimizing the process of open combustion. It is necessary to achieve the emission of gases, which are the source of heat. On the basis of these principles, top-combustion boilers and pyrolysis units operate. Let's talk about them further.

Types of long burning boilers

There are two types of solid fuel aggregates operating on wood:

• Pyrolysis.
• Systems with an upper loading method.

Both options provide an opportunity to get a high-quality autonomous heating system.

Top-burning boilers: features

In ordinary boilers, as well as in furnaces and fireplaces, the fuel burns from the bottom upwards. This can be explained by the physical processes during combustion. This scheme is ineffective. This deficiency is completely eliminated in such units. What is the peculiarity of a long-burning boiler with upper combustion? It is a way of transforming energy. So, the fuel does not burn down, but from above. Air is also supplied from above and directly to the combustion zone, and not from below through special grates. These are non-volatile heat sources - and this is a plus of such systems. But they differ in the cycle of work. While the bookmark does not burn, you can not add another one. The furnace chamber of such boilers is quite capacious. At the bottom of the fuel does not burn - it waits until it comes to turn. As the upper layer burns down, the lower one is activated. Air is fed from above through special channels or scatterers. These channels are hot from below. The air from the top of the combustion chamber gradually falls down. By heating, it reacts more quickly with solid fuel. Thanks to this, the high efficiency of top boilers is ensured.

The distributor of air in the combustion chamber can move - it is able to rise when laying fuel. When the process of burning begins, it relies on fuel. So oxygen will fall only into the combustion zone. There is only smoldering, and the products of combustion fall exclusively in the upper part. There they are separated by a massive metal disk. Then air is added to these gases, and the products are burned. And the heat produced will fall on the heat exchanger.

Often these systems have a cylindrical shape. However, there are rectangular models. The combustion chamber, as already mentioned, is quite capacious, due to which the maximum duration of the combustion process is reached. Cylindrical shape makes the device compact and allows you to save space.

Benefits

Boilers with a top-burning fuel are sufficiently durable and reliable. Due to the gradual distribution of the load in the combustion zone in the direction from top to bottom, the boiler body does not warm up to more than 400 degrees. Due to a simpler design, such systems are safer than gas or electric systems.

Often such units are designed for different types of solid fuel. This can be firewood, coal, peat, various combustible mixtures, granules, waste wood production. The combustion process can last up to 5 days, depending on the design. If you use wood, then one loading of the boiler top burning can suffice for a period of 8 to 30 hours.

disadvantages

By the minuses of this equipment can be attributed demanding and finicky to the quality of fuel. If you make the unit work on raw firewood, its efficiency will decrease substantially. The optimum level of fuel humidity for solid fuel boilers of long burning with upper combustion is 13-20%. If you use a more crude product, the boiler will produce significantly less heat. In addition, in this situation, the device can even go out. In addition, if you burn raw firewood in a boiler, soot and ash will be emitted. It is necessary to periodically clean both the furnace and the chimney. Also, the disadvantages can be attributed the need for manual loading.

Pyrolysis

A slightly different principle is used here. The mechanism is based on the splitting of fuel into pyrolysis gas and coke. This problem is solved due to the low intensity of combustion. Fuel does not burn, but smolder. As a result, a gas is formed that burns, connecting with oxygen.

Why are not there wall-mounted?

A long-burning boiler with top loading is performed only in a floor form. Its weight is too big for wall mounting. But constructively - this is the most common solid fuel boiler. Power depends on the destination. The equipment can not only heat the premises, but also heat the water. In this case, the heat exchanger can be flowing or can be used as a storage tank. The heat exchanger can be both steel and cast iron.

A boiler made of cast iron is less susceptible to corrosion. This is a very important characteristic. Condensation appears on the walls of the chamber, and this is quite an aggressive environment. Cast-iron boilers are made in the form of sections. This makes the transportation process much easier.

And if independently?

It is quite possible to make a boiler of top burning and with own hands, and from improvised means. This requires a two-hundred-barreled barrel, a pipe and a channel. So, in the barrel the upper part is cut out, and the edges are leveled. A hole is made from above. A pipe is inserted into it, which is directed upwards. It is made with a damper to regulate the air supply. The most difficult stage is regulation. The pipe should not be too low, otherwise the combustion process will be rapid. If you equip such a structure with a special cargo, due to which the fuel will settle slowly, as well as a mobile air distribution system, you can get a fairly efficient system. One bookmark will burn in 20 hours.

Conclusion

Boilers for upper combustion with solid fuel are an excellent and economical way to provide the house with heat. The price of such heat will be very affordable. The cost of the new unit of this type starts from 50 thousand rubles, which is quite acceptable.