IEA (International Energy Agency) District Heating. State-of-the-Art Review of Coal Combustors for Small District Heating Plants.

摘要

The most important types of conventional firing systems for small district heating plants are chain-grate stokers and vibrating-grate stokers. Fluidized combustion is fairly well developed for small heating boilers, but it is not yet fully proven through widespread operating experience. It has the best overall potential of all the firing systems for application to small district heating plants, and it is of special interest for firing low-grade coal or coal waste where these are available as low-cost fuel. The primary areas where additional research and development would be beneficial to coal-fired heating plants are: fuel handling; flyash recycle; ash handling; and automatic operation. Further development work should be especially helpful for FBC boiler systems, particularly for solid handling systems for low-grade coal and coal waste. The general potential for the increased use of small coal-fired plants in district heating was fairly good in 1985, but it was significantly reduced by the decrease in fuel oil and natural gas prices in 1986. OPEC and some other oil-exporting countries are trying to bring about higher oil prices by reducing production, however, and it would not be unlikely that oil prices will increase to some extent in the foreseeable future.