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Document ID (ISN)102930
CIS number 03-1776
ISSN - Serial title 1219-1221 - Central European Journal of Occupational and Environmental Medicine
Year 2002
Convention or series no.
Author(s) Abdel-Shafy H.I., Hegemann W., Schenk H., Wilke A.
Title Decreasing the level of heavy metals by aerobic treatment of tannery wastewater
Bibliographic information 2002, Vol.8, No.4, p.298-309. Illus. 20 ref.
Abstract In this study, the efficiency of an aerobic process for the treatment of tannery wastewater as well as the level of heavy metals throughout this process were investigated. The level of chromium in the produced sludge and the treated wastewater was evaluated. The adsorption isotherm of the "free metal sludge" for chromium was also studied. The study was carried out in a continuously controlled pilot plant system. Results show that the aerobic treatment reduced the chemical oxygen demands (COD) of the wastewater. Heavy metals were concentrated mostly in the sludge. Chromium was eliminated in the wastewater by 46.3%. The levels of the other metals were also reduced with a range of elimination from 19% for zinc to 58.3% for manganese. Nevertheless, the concentrations of chromium both in treated wastewater and sludge exceeded the permissible level. It is recommended that further treatment be applied to decrease chromium to the permissible level.
Descriptors (primary) water treatment; metals; tanning industry; water pollution; effluents
Descriptors (secondary) manganese and compounds; manganese; zinc; sludge; oxygen; description of technique; chromium and compounds; chromium; zinc and compounds; oxygen enrichment
Document type D - Periodical articles
Country / State or ProvinceGermany; Egypt
Subject(s) Leather, fur and footwear
Broad subject area(s) Chemical safety
Browse category(ies) Environmental pollution
Footwear, leather and fur industry
Inorganic substances