Effects of different thiobacillus on bioleaching of heavy metals of sewage sludge in a sequencing batch reactor

摘要

A bioleaching experiment was carried out in two sequencing batch reactors (SBR) of 80 L. ACIDITHIOBACILLUS THIOOXIDANS (A. t) and ACIDITHIOBACILLUS FERROOXIDANS (A. f) were enrichment cultured by adding sulfur powder and ferrous sulfate as substrate respectively. Sequential batch leaching ran for three periods in succession. The average removal rate of As, Cd, Cr, Cu, Ni, Pb, Zn was 90.46%, 90.28%, 90.70% and 79.70%, 81.19%, 84.52% respectively. The average loss rate of total nutrient (total account of organic matter, TN, TP and TK) is 35.36%, 33.36% and 35.54% for three runs in sequence. Comparing with A. F, the acidification time of A. T is shortened by 3.0, 6.6 and 4.9 d, with the increase of 13.5%, 11.2% and 7.3% for the removal rate of heavy metals.