A Study of Migration and Distribution of Sulfur During Pyrolysis and Conversion of Coking Coal

Taking the comonly used coking coal of Masteel as an example, the representative coking coals with various sulfur contents were chosen as the object. The fixed-bed coal pyrolysis and carbonization experiment was carried out to study the migration and distribution of sulfur as well as desulfurization rate in the process of coal pyrolysis. The results show that coal type is the key factor affecting the transformation and migration of sulfur, sulfur form distribution and desulfurization rate of coal pyrolysis. Compared with coking coal, gas-fat coal and fat coal favor the transformation of sulfur species into gas phase with similar proportions. More sulfide in gas-fat coal is transformed and migrated to liquid products, and both fat coal and coking coal are low and the proportion is close. The desulfurization rate is closely related to the type of coal, which is in the order of gas-fat coal>fat coal> coking coal. The pyrolysis transformation and migration of different forms of sulfur components in coal are in the order of sulfides and pyrites>sulfones>sulfoxides. The removal of thiophene and sulfates are related with the sulfur content of coal, and the thiophene in high-sulfur coal are relatively easier to be transformed and removed, while sulfates are more difficult, but this is contrary to the case of medium-high-sulfur coal.