Pellets - what is it? Pellet production line. Pellet oven

The experience of European countries in the use of pellets demonstrates the effectiveness of this type of fuel in terms of heating function, as well as the economic feasibility of its use. In Russia, this resource is less popular, but the conditions for energy supply make it necessary to contact all new consumers. Promotes the distribution of pellets and the development of manufacturing technologies, which allows you to expand the range. Some modifications of heating boilers are designed for combined use of fuel. This eliminates the risk of switching to a new combustible material and facilitates the operation of the equipment. To answer the question: "Pellets - what is this?" - it is necessary to consider production technologies, used raw materials and characteristics of this type of fuel.

General information about pellets

The composition of pellets usually includes logging waste (bark, chips, sawdust), but there are other types of raw materials, including agricultural products. Depending on the recipe, pellets can include waste from straw, corn, sunflower, as well as cereal elements, litter, etc. The presence of such a list of components may seem questionable in terms of energy efficiency, but this is another matter: pellets - what is it from the point of view Applications in the heating system? They are rightly called fuel granules, in which there are no toxic and synthetic components. Again, depending on the composition of the consumer receives at the output of a fuel product with a minimum of ash coefficients and environmentally friendly.

Production technology

The production chain is rather short, which makes it possible to produce pellets on their own. Of course, special equipment will be required, but for now it is worth considering the production stages:

• Preparation of raw materials. As a rule, special crushers are used.
• Drying. The semi-finished product is placed in a drum or tape chamber, where it acquires a sufficient moisture index - on average 10%.
• Grinding of the finished mass by means of hammer- type mills .
• Water or steam humidification. Screw mixers are used for efficient gluing during pressing.
• Further, a pellet press is used, which can be a cylindrical or flat structure, which assumes further cooling of the workpiece.
• Filtration and packing of pellets.

To irrefutable advantages of the technology of manufacturing wood pellets is wastelessness. This is rare even in the wood processing industry, which produces heating products. In the traditional version, the pellet production line assumes only one stage of control for the rejection - sieving. But the filtered granules are not disposed of, but are used in subsequent production cycles.

Equipment for the production of pellets

There are different configurations for the technical organization of production lines for fuel pellets. They can be assembled at the expense of individual industrial plants or use ready-made mini-granulators. There are conveyors and the type of drive - electric, diesel, gasoline, etc. Anyway, the most important element that the pellet production line has is a granulator. This unit often replaces the work of high-grade crushers and presses.

Also, depending on the volume of production and the raw materials used, you may need a chipper (grinds solid wood waste), drying equipment and a semi-finished product cooler. All described operations are able to perform a multifunction machine for pellets, which can work on one of the most common types of raw materials. However, the cost of such equipment is quite high - at least 300-400 thousand rubles.

Boilers for fuel pellets

To date, a whole class of heating equipment has been developed, designed to consume biofuel. The design of most boilers in addition to the housing provides for the presence of the following elements:

• The furnace.
• Burners.
• Fuel compartment.
• Heat exchanger.
• Smoke duct.

As you can see, the pellet stove repeats the usual wood-burning boilers in terms of the structural design , but there are also fundamental differences. In many ways, they are reduced to the parameters of the combustion chamber, which has a small space. The fact is that the heat transfer is carried out in a complex convective part of the unit, which allows providing a considerable efficiency - on average 80%. The combustion is also facilitated by the design of the burner, which makes the boiler function more productive and economical.

Types of boilers

Despite the relative novelty, the pellet heating systems have already managed to take the form of several types:

• Models focused on working exclusively with fuel pellets.
• Combined aggregates. The furnace device in such boilers assumes the possibility of transformation, which makes it possible to use ordinary solid fuel materials in addition to pellets. However, the main fuel for such equipment is still biogranules.
• A universal pellet kiln, as a rule, has several combustion chambers, each of which is capable of taking a certain type of fuel in its characteristics.

Regardless of the type of pellet boiler, almost all modern models provide ample opportunities for programming and automation. Automation is also provided in the granule feeding system from the hopper. The combustion chamber is supplied with practically no human control - as needed and as long as there is a stock of pellets.

Where are pellets used?

Again, according to the experience of European countries, it can be said that granular fuel is universal. It is also used for servicing district boiler houses, and privately. However, in Russia many still have a question: pellets - what is it? Fuel for industrial facilities or a means for heating private houses? In fact, this biofuel can not simply be used as an alternative to gas and firewood, but also to show better results of energy supply.

By the way, fuel pellets are actively used in regions where there is no stable provision of backbone grids. Autonomous heating of the house with pellets gives weighty advantages for remote cottage settlements. In addition to the heating function, pellets are able to perform the tasks of eliminating liquid products. This is due to their use as fillers for toilets for pets, as well as for the elimination of emergency areas in floods.

Ecology and the secret of efficiency

This type of biofuel, of course, has many advantages, but some of them are exaggerated, which misleads the consumer. One of the myths comes from the high efficiency of granules, which supposedly is possible only if artificial modifiers are added, which exclude the ecological compatibility of the product. Indeed, the production of fuel pellets in some formulations involves the introduction of chemical additives. However, in Russia the standards of manufacture completely exclude this, and optimum combustion performance is achieved due to low humidity and high density.

Pellet storage conditions

Perhaps, this is one of the most important drawbacks of fuel pellets. They require the creation of special storage conditions. In any case, the requirements in this regard are tougher than to traditional solid-fuel materials. To understand the nuances of storage it is important to remember: pellets - what is it. These are compressed crushed wood particles, in the creation of which there are no binding components. Therefore, any exposure to moisture can lead to the destruction of the granule. Even without direct contact with water, prolonged storage on the street will cause the pellets to become saturated with moisture from the air. Accordingly, storing biofuel of this type is desirable only in rooms where there is no dampness and temperature differences.

Conclusion

If we take into account all the advantages of fuel pellets, then the question arises as to why they are still perceived only as an alternative to gas and firewood? Partly this is due to the fact that wide layers of consumers about pellets are not yet aware, although the situation is changing. Expansion of production, introduction of new biofuel production technologies and the emergence of efficient boilers for fuel pellets increase the interest of consumers in this topic. So there are questions about the rejection of firewood, coal and gas: will they be replaced by pellets? Reviews do not yet give an unambiguous assessment.

Obviously, there are advantages in the form of ergonomics of the use of pellet boilers, high efficiency and safety. But there are disadvantages, among which consumers allocate high prices of boiler equipment, the problems of their compatibility with imported fuel pellets and the search for stable suppliers. In some cases, saving is not so indisputable. For example, if there is a choice between wood and pellets, the second option in terms of reducing costs is fully justified. However, compared to gas, biofuels are not so profitable. Nevertheless, if there is no possibility of connection to the central supply lines, the pellets become the only economical choice.