Compaction of waste esp. clarification sludge - to obtain strong pressings for use in coal pressure gasification

摘要

In the consolidation of pasty organic residues and wastes (pref. clarification sludge) for use in coal pressure gasification, involving mechanically dewatering to below 80% moisture content and then adding moisture-binding material, the novelty is that (a) the clarification sludge content in the pressed material is greater than 20 (pref. 30-40)%; (b) the moisture-binding material is dry blown coal dust (pref. filter dust from briquette mfr.) with max. 11% water content and/or max. 20% water content, dry clarification sludge with max. 20% water content and/or paper with max. 15% water content; (c) intensive mixing of the components is carried out by simultaneous or separate forced mixing and strong comminution; and (d) press compaction is carried out at 20-120 MPa pressure. Press compaction is repeated to increase the transverse compressive strength of the pressings. ADVANTAGE - The process converts mechanically dewatered clarification sludge with 60-70% moisture content into a material which can be pressed to pressings having sufficient strength for transport and high thermal stability for the gasification process.