For the private sector, houses of suburban construction, the autonomous heating system plays a special role. For the category of citizens who use gas boilers, there are no special questions. The situation is more complicated for the category of the population that is forced to use solid fuel heating appliances for home heating. For solid fuel boilers, wood or coal is traditionally used as the main fuel resource. However, recently such type of organic fuel as pellets is gaining popularity. Solid fuel pellet boilers produced today are powerful, economical and easy-to-use heating devices.
Due to its performance, this type of heating equipment is able to compete with gas heating. For the central and northern regions of the country, rich in forest resources, the production of pellets is one of the sources of income for woodworking enterprises. Therefore, if you have a real opportunity to get constant access to this type of solid fuel, bet on pellet boilers. You won’t go wrong!
Read also about pellet stoves.
Some information about pellets. What it is?
Pellets are cylindrical granules 5–7 cm in size, made from wood waste. The diameter of such a granule is slightly more than 6–8 mm. The size of the granules is affected by the quality of the raw materials used and the method of production.
Under pressure, wood raw materials are compressed, due to which a high density of the substance is achieved. Granules, unlike wood, sink in water. In the manufacturing process, the required moisture content of the composition is reached, not more than 10%. Such strict parameters for the finished product are caused by the desire to achieve maximum results in the combustion process. Long-burning boilers, pyrolysis-type units are very willing to use pellets as the main type of fuel.
Important! When choosing a heating boiler for yourself, evaluate in advance from which supplier you will receive fuel. Pellets from different manufacturers differ not only in size, but also differ in the composition of the raw materials. Otherwise, the boiler will operate unstably, giving out different technological parameters each time.
In furniture factories and woodworking enterprises, such waste occurs daily, and in huge quantities. Abroad, this has long been used, using wood waste as a fuel raw material. As a rule, for the manufacture of this fuel, mainly softwood-based production waste is used. The cost of such products is not high. Raw materials for production are always available in sufficient quantities.
Less often, furniture production waste is taken for manufacturing, where expensive types of wood are more often used. Such pellets burn better and last longer. The only negative that is obvious in this case is the high price of such fuel.
Today, waste from the main products of agriculture and the food industry is actively used for the manufacture of fuel pellets. Husks from sunflower seeds, the remains of corn cobs are excellent raw materials for burning.
The main advantage that pellets have is full combustion in the furnace of boiler equipment. This type of fuel has a high calorific value, which is similar to the combustion of coal. If it is possible to use pellets all the time, why not take advantage of this. What to give preference to a pellet unit or a solid fuel boiler in a classic version, choose the first option.
On a note: according to specialists of heating engineers, a pellet boiler is more economical. The efficiency of such a unit is 1.5–2 times higher than any other solid fuel boiler equipment.
The principle of operation of the pellet boiler
What is the difference between a heating device that works on pellets and what are its main design features, let’s take a closer look.
At first glance, this type of equipment may seem simple and unpretentious in operation. However, it only seems so. A modern solid fuel pellet boiler is a high-tech product equipped with all the equipment, devices and mechanisms related to this technique. It should be said right away that the key factor for the subsequent evaluation of the heating apparatus is the capacity of the fuel bunker. The larger the hopper, the longer the heating device will work without human intervention.
The whole process of operation of the boiler on pellets can be conditionally divided into the following stages:
- stage one, fuel supply;
- stage two, the combustion process;
- heat transfer process.
The heating boiler itself works as follows. The fuel in the bunker is fed into the combustion chamber automatically, due to the screw transmission, i.e. in portions. As it burns, new pellets are constantly fed into the furnace, due to which the combustion process is constantly maintained. Pellets entering the firebox burn out completely, which minimizes the formation of ash and soot.
In the future, the design of this type of boiler equipment will differ from traditional ideas about the principle of operation of solid fuel units. The combustion process mainly takes place not in the combustion chamber itself, but on the burner, which has a certain shape and design. As soon as the burner stops receiving fuel, the combustion process automatically stops. Those. if you calculate in advance the volume of fuel needed to heat the room, you can achieve almost complete autonomy of the entire process.
On a note: burners in pellet boilers are of two types: retort (volumetric combustion) and flare.
Burners in a solid fuel pellet boiler are the main operating mechanism. Supplied under high pressure, due to the operation of the supercharger and the presence of nozzles, the air contributes to the high intensity of fuel combustion. During operation of the boiler, the heating temperature reaches 4500FROM.
A retort burner is a device in the form of a bowl, in which there are longitudinal holes (nozzles) on the sides. Air enters through these holes, on which the intensity of combustion depends. Depending on the design of the unit, pellets enter the bowl from above or are pushed out due to the operation of the auger from below. In this case, combustion occurs. The whole process, taking into account the quality of the burner, is monitored by a controller, a special device that records the flow of fuel into the burner.
Flare burners work differently. Here, the pellets enter a special platform, where they are blown with air, which results in a powerful and stable torch. The flame in this case is directed in a horizontal plane. The volume of air supplied by the fan is sufficient for complete combustion of fuel pellets. Both the first and second types of burners cope well with the task of heating the water jacket of the boiler.
Processes running in automatic mode. The main advantages of pellet boilers
Comparing solid fuel units operating on pellets with conventional boilers, special attention is drawn to the presence of automated processes, which not only improve the performance of boiler equipment. Pellet boilers can be considered almost autonomous heating devices. Factory models have the following advantages:
- precisely calculated dosage of fuel for supply to the boiler furnace;
- automatic ignition and extinguishing cycle of the burner;
- technical ability to adjust the intensity of combustion;
- technological control over the degree of heat exchanger heating;
- pressure control inside the boiler equipment;
- automated traction control.
All of these processes meet the requirements that apply to almost all heaters used for domestic heating systems. The latest factory products are distinguished not only by high performance and efficiency (92%), but also by a high level of safety. You can list the advantages of this technique for a long time. The only negative of all this is the high price of equipment, when compared with classic-type boilers.
A solid fuel boiler, along with a pellet burner, can be made by hand, with a little effort, upgrading an existing heating device at home. Alteration of solid fuel boilers for pellets will not take much time. It is enough to make changes to the combustion chamber of the unit and purchase a special burner. Re-equipment will take some time, cost a certain amount, but in the end it will be possible to count on good performance of the heater in a new role.
As a result, having evaluated all the advantages and technical capabilities of pellet boiler equipment, we can draw a very definite conclusion. This technique is relevant today and can successfully compete with gas units. For residents of areas where there is no centralized gas supply system, pellet boilers are able to solve all the household needs of the inhabitants of the house. High power, high productivity and, most importantly, the possibility of long-term operation without human intervention make such equipment very popular.
Having on hand the calculation of fuel consumption, you can achieve long-term operation of the heating system without your participation. For heating a living area of 100 sq. meters (with a ceiling height of 2.8–3 m), 100 kW of thermal energy is enough, which corresponds to the combustion of 25–30 kg. pellet. Consequently, a little less than a ton of this fuel will be required per month. Of course, at a cost, such fuel is 5–7 times more expensive than natural gas, however, in its absence, pellets are the best alternative to coal and ordinary firewood. Which boiler to choose for installation in your own home is up to you.
If you want to have cleanliness, warmth and comfort at home. On top of that, if you want to have more free time, solid fuel pellet boilers will be a great find. You don’t have to become a stoker, you don’t have to run around at night and see that the boiler doesn’t go out. With such equipment, your country house or cottage will become much more comfortable and cozy.