Premium
Thermal pretreatment of concentrated distillery spent wash
Author(s) -
Lele Smita S.,
Shirgaonkar Irfan Z.,
Joshi Jyeshtharaj B.
Publication year - 1992
Publication title -
water environment research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.356
H-Index - 73
eISSN - 1554-7531
pISSN - 1061-4303
DOI - 10.2175/wer.64.3.9
Subject(s) - chemistry , residue (chemistry) , fraction (chemistry) , pulp and paper industry , dilution , waste management , biodegradation , filtration (mathematics) , chromatography , biochemistry , physics , statistics , mathematics , organic chemistry , engineering , thermodynamics
A novel thermal pretreatment reported earlier was employed to treat concentrated distillery spent wash to reduce the quantity to be handled at high pressure and high temperature involved in the proposed process. Three types of concentrated wastes, namely, high molecular weight high COD fraction obtained after membrane filtration of distillery waste, concentrated wastes obtained from distillery employing indirect heating, and concentration by partial evaporation of spent wash under vacuum, were studied to establish suitability of the proposed process for concentrated wastes. Thermal pretreatment at 230°C for 2 hours resulted in formation of charred residue having properties like lignite coal. The reduction in COD of the liquid phase was due to the separation of residue. Effect of dilution by treated waste on pretreatment was studied to estimate backmixing effect. Attempts were made to evaluate performance of different concentrated wastes in terms of extent of COD reduction, net energy recovery, and biodegradability. Other operational parameters, such as filterability, total pressure, and ease of handling of residue, were also evaluated. Thermal pretreatment of membrane‐filtered, concentrated fraction appeared to be promising.