Absolutely not each grade of coal is suitable for solid propellant boilers of long burning. If in normal furnaces it is possible to fill up fuel of any fraction, then in modern it is necessary to select coal carefully. At low-quality product the mobile grid-irons will be hammered with slag and if to lose with fraction – coal from the camera of burning will fail in ashpit.
Instruction
1. For solid propellant boilers it is recommended to use brown coal which differs in low ash-content, but also it allocates to heat energy in the course of combustion a little. If to consider that its cost in some regions 10 times more, than stone, then it is not favorable to buy it at all.
2. Stop the choice on grade coal "Mine nut". It has fraction of 25-50 mm therefore optimum is suitable both for boilers of long burning, and for normal furnaces. The only shortcoming – in the market can be met the coal containing big percent of breed which does not burn down completely, hammering at the same time grid-irons.
3. If in your region coal is provided much, buy long-flame, gas or anthracite. The last gives a lot of heat, but not important burns therefore it is undesirable to use it for non-automatic boilers. On sale it is possible to meet greasy coal, it is extracted in places where to the accompanying minerals serve oil. Fuel though well burns, but strongly litters flues because the structure contains some part of oil products.
4. Refuse coal purchase if you notice that its structure non-uniform, and the fraction does not correspond to stated. It is too much "sunflower seeds" which in the people is called dust, speaks about poor quality of fuel. Coal will not only burn badly, but also to leave behind huge amount of ashes.
5. Quality coal has almost uniform color. If you notice that some stones are allocated with grayish-whitish shade - it is breed which will not burn and give heat. Large amount of fireproof impurity considerably increases coal bucket weight – is absolutely unprofitable to buy such fuel.
6. If you have opportunity to go to several organizations, engaged in selling of coal, use it. So you will be able to evaluate fuel on exterior even before delivery to you, and respectively if something does not suit you – will be to refuse purchase not late.