MANUFACTURING OF BRIQUETTES FROM TYPICAL HIGHVELD COAL FINES USING VARIOUS BINDERS

摘要

The possible utilization of agglomerated fine coal is becoming an important issue for example in gasification processes and thus the need arose to briquette inertinite-rich fine coal by using a suitable binder to reduce the briquetting pressing temperatures and pressures.rnIn this study, eleven binders, including two types of clay, bio char, cow dung, lignosulphonate, kraft lignosulphonate, paraffin, polyester resin, wax and two South African coal tar pitches were mixed in a concentration of between 0 and 10 wt.% with the inertinite-rich, high ash coal. The cured (cured at 100 ˚C for 3 hours) and uncured briquettes were compared to each other by means of compression strength, drop test and a water submersion test. It was found that the uncured bound briquettes and the binderless briquettes yielded a similar compressive strength, whilst the binderless, cured briquette showed an average compressive strength of about five times more than those uncured or binderless briquettes. The lignosulphonate and resin bounded briquettes yielded the highest compressive strengths of 16 and 12 MPa respectively at a 7.5 wt. % binder concentration. All briquettes retained their shape and size during drop tests and none of the briquettes proved to be water resistant; hence paraffin and wax were used as waterproofing agents after pressing and curing.