Studies on the cleaning potentialities of high ash Indian non-coking coals for meeting the MOEF's stipulations

摘要

The non-coking coal constitutes about 85% of the Indian coal reserves and the depositions remained mostly as low rank sub-bituminous and non-coking type. The vast reserves of the non-coking coal are usually high moisture, high ash, high volatile and sub-bituminous types (Ro% ranging between 0.4 and 0.65). The stipulation laid by the Ministry of Environment and Forest (MOEF), Government of India to transport coal of ash not exceeding 34% beyond 500 km is posing problems to different coal suppliers for the dispatch of its coal to the power plants. The only solution to this problem appears to be the setting up of washeries to reduce the ash content. With a 66% share of installed power generation capacity, the coal industry has a major role to play in the nation's development. The coal washing capacity from all the 52 washing plants is 131Mtpa, indicating that around 30% of the coal is being washed before it is used in power stations. The paper highlights the washability studies carried out on high ash coals, the beneficiation methods required for coal washing in India and various technologies being adopted thereof for washing of Indian coals.