Removal of Cu(II) ions by biosorption onto powdered waste sludge (PWS) prior to biological treatment in an activated sludge unit: A statistical design approach

Pamukoglu M. Y., Kargi F.

BIORESOURCE TECHNOLOGY, vol.100, no.8, pp.2348-2354, 2009 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 100 Issue: 8
  • Publication Date: 2009
  • Doi Number: 10.1016/j.biortech.2008.11.032
  • Journal Name: BIORESOURCE TECHNOLOGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.2348-2354
  • Keywords: Activated sludge, Biosorption, Box-Behnken design. Cu(II) ions, Powdered waste sludge (PWS), Toxicity, BATCH REACTOR, COPPER(II) IONS, BIOMASS YIELD, HEAVY-METALS, TOXICITY, CHROMIUM(VI), KINETICS, PERFORMANCE, PARAMETERS, NICKEL(II)
  • Dokuz Eylül University Affiliated: Yes

Abstract

Biological treatment of synthetic wastewater containing Cu(II) ions was realized in an activated sludge unit with pre-adsorption of Cu(II) onto powdered waste sludge (PWS). Box-Behnken experimental design method was used to investigate Cu(II), chemical oxygen demand (COD) and toxicity removal performance of the activated sludge unit under different operating conditions. The independent variables were the solids retention time (SRT, 5-30 d), hydraulic residence time (HRT, 5-25 h), feed Cu(II) concentration (0-50 mg L-1) and PWS loading rate (0-4 g h(-1)) while percent Cu(II), COD, toxicity (TOX) removals and the sludge volume index (SVI) were the objective functions. The data were correlated with a quadratic response function (R-2 = 0.99). Cu(II), COD and toxicity removals increased with increasing PWS loading rate and SRT while decreasing with the increasing feed Cu(II) concentration and HRT. Optimum conditions resulting in maximum Cu(II), COD, toxicity removals and SVI values were found to be SRT of 30 cl, HRT 15 h, PWS loading rate 3 g h(-1) and feed Cu(II) concentration of less than 30 mg L-1. (c) 2008 Elsevier Ltd. All rights reserved.