The comparison of existing technologies of coal processing into ash product is carried out. The processes of thermal dissolution of coals and production of pitch from coal tar are taken as a basis. The most suitable raw materials for the thermal dissolution process are hard coals of G, GZh, Zh grades. Anthracene oil is the most effective solvent for the organic mass of coals. The process of thermal dissolution of hard coals should be carried out at temperatures of
350-400 °С.
To obtain coal tar, from which coal pitch will be obtained, the initial raw material is coal charge, which is formed during coking of coals of the following grades: G, Zh, GZh, KZh, KK, KO, OS.
According to GOST 10200-2017 "Electrode coal pitch", the obtained pitch complies with the following requirements:
- softening point, °С - 85-92;
- mass fraction of substances insoluble in toluene (α-fraction),
% - not less than 31;
- mass fraction of substances insoluble in quinoline (α1-fraction), % - not more than 14;
- yield of volatile substances, % - not more than 57;
- ash content, % - not more than 0.3.
Peck used as a raw material for carbon fiber production meets the following requirements:
- mesophase content, % - not less than 40.
- softening point, °С - not less than 190.