Peat pellets: inexpensive, practical and effective.
Solid fuel boilers are considered to be among the most cost-effective, because almost anything can be used as fuel in them: wood, coal, peat and sawdust. Practice shows that one of the most effective boiler types (95% efficiency) is the pellet boilers utilizing compressed combustible materials in the form of pellets. Given that peat is one of the underutilized until recently materials that have calorific value, it is obvious why the peat pellets that have become one of the major fuels used for solid fuel boilers of various sizes over the last few years.
ADVANTAGES OF PEAT PELLETS.
Since peat is a natural material consisting of organic residue of marsh plants, it is composed entirely of carbon and is as environmentally friendly as possible. It is easily crushed and pressed into pellets. Because of its natural structure, peat burns slowly and has a low ash content (3.6%). With respect to heat value (the amount of heat generated by 1 kg of fuel), peat pellets are equal to coal. For comparison: the amount of heat generated by combustion of 1 kg of pellets from peat is 4500-5500 kcal, 1 kg of coal gives 3800 -5900 kcal, 1 kg of wood 3000-3300 kcal. That is why the combustible material is widely used in both industrial and domestic heating.
PHYSICAL PROPERTIES OF PEAT PELLETS.
The cost of peat is much lower than the cost of coal or firewood because of the ease of extraction. Peat pellets are made from the so-called milled, i.e. crushed peat. For ease of molding into pellets, peat is pre-softened with steam and dried to a moisture of 8-12%. Peat granules do not have a pungent smell; peat does not produce dust, and does not emit harmful substances during storage. Pellets are easily stored; because of their compactness, there is no need for large spaces. Another advantage is that peat does not require further processing, it is sufficient only to launch its production, produce pellets, and it is ready for use.
PECULIARITIES OF PRODUCTION OF PEAT PELLETS.
Production of peat pellets can be divided into 4 stages:
- Grinding is done in hammer mills to produce particles of less than 10 mm, then peat passes through the mesh screen to obtain particles of only the desired size.
- Drying occurs in special drums, where peat is treated with hot air. Peat moisture is reduced from 40-45% to 8-9%.
- After drying peat is passed through hammer mills one more time and then it can be compressed.
- Peat pellets are pressed on a roller- matrix press of continuous action. Before pressing, the peat is treated with dry steam to soften and activate adhesives. After pressing, the pellets are cooled and taken to the packaging shop. Depending on the end-user the granulated peat is packed in big bags, small bags or packages or distributed bulk in wagons as well.