Optimization of effective parameters in the biological treatment of heavy metals (Nickel, Copper) using sequencing batch reactors (SBRS)

Subject Areas : environmental management

Morteza Khosravi ¹ , Mohammad Rabani ² , Mohammad Reza Allahgholi Ghasri ³ , Mohammad Javad Ebrahimi Zarandi ⁴

1 - Faculty of Chemistry, Tehran North Branch, Islamic Azad University
2 - Faculty of Chemistry, Tehran North Branch, Islamic Azad University
3 - Faculty of Chemistry, Tehran North Branch, Islamic Azad University
4 - Faculty of Chemistry, Tehran North Branch, Islamic Azad University

Received: 2007-04-04 Accepted : 2007-06-23 Published : 2009-09-23

Keywords: Biological treatment, Optimum parameters, Nickel II, Copper II, sequencing batch reactors,

Abstract :

This research aimed at optimizing the effective parameters such as pH, activated sludge volume, concentration range, and fluid flow in the biological treatment of heavy metals (Nickel, Copper). The researchers studied the biological treatment of the above-mentioned metals in presence of activated sludge at Ghaytarieh wastewater treatment plant in Tehran as well as aeration with mixture. Then, such parameters as pH (8±0.3), activated sludge volume 30%, concentration range of Cu II (800-1200) mg/lit and Ni II (800-1000) mg/lit were determined. For the biological removal of Cu II and Ni II (1000 mg/lit), three Plexiglass sequencing batch reactors with a total volume of 24 liters were used with sludge volume 30%,  pH (8±0.3), DO (6-8) mg/lit, dissolved oxygen (6- 8) mg/lit, and optimum fluid flows 40 ml/min. The following results were obtained: Removal of Cu II: 99.74% Removal of Ni II: 92.4 % Decrease of BOD5: 81.65% Decrease of COD: 78.13%                                      SVI: 62 ml/g