Chromium Tannery Sludge Bioleaching Technical Analysis&Resource Utilization Studies

China has become the world’s major producer of leather. It brought rapid economicdevelopment and environmental pollution. Now most enterprises are facing tannery sludgeharmless and resource urgent choice. The bioleaching process had better removal of heavymetals in the sludge and handled conditions of relative simple process. This paper mainlydid research on tannery sludge, and investigated the feasibility of sludge acclimationindigenous culture. It studied the removal role of heavy metals Cr under biologicalfiltration with different factors and determined the the optimum bioleaching processparameters and the application of bioleaching process of stripping reactor on the basis.After that it analyzed the nature of the sludge after bioleaching and attempt to land useafter adjusting the pH of sludge leaching.1) The paper made municipal sludge and sludge as seed sludge starch, by comparison.The experiment chose a starch suldge to sludge indigenous culture Thiobacilli in sludge, itwas applied to tannery sludge bioleaching process through enrichment. Heavy metals inthe sludge Cr (Ⅵ) removal rate are higherover95%.2) The study found tannery sludge inoculated20%starch sludge acclimation, thedosage of energy substances S powder was7g/L, temperature was controlled at28℃,aeration rate was1.0L/min L, acidified sludge reflux ratio was at3/4, it can achievebetter results bioleaching.3) On the basis of the optimal process parameters determined by the staticalexperiment, the homemade Airlift bioleaching reactor was open to run, and multi-batchcontinuous operation, heavy metals Cr dissolution was up to over95%.4) The paper analyzes the nature of the tannery sludge, and found that heavy metalsand nutrients TN, TP levels can meet the requirements of land use after bioleaching. ThepH value of sludge after leaching was used to plant potted rape, compared with the controlgroup rape; the condition of this group of rapes is the best.5) The paper proposed that the biological effects of other process parameters leachingshould be researched further; expanding the scale reactor experiments to explore thedynamic operating parameters of the experiment; paying attention to recycling and use ofheavy metals Cr (Ⅲ) in leaching.