Study For Treating Wastewater In TNT Production Using Microorganisms Immobilized On Chitosan

The explosive's factory effluent has the characteristics of complex composition, high organics concentration, hardly biodegradable macromolecular compounds, high nitride, powerful toxicity and so on. It will badly pollute the environment if we don't take reasonable anti-fouling steps.The technology of immobilizing microorganisms for wastewater treatment can improve the microbion's concentrations, mass transfer efficiency and treatment results in the catalyst chamber. It limits microbion' contact with poison and improves the ability of resistance to poison. It is helpful to separate solid from liquid and reduce regular investment. At present, it is an important biological way for treating hardly degradable organic pollutants.The research work prepared immobilization anaerobic sludge ball with chitosan as carrier using embedding technology. It compared bioactivity of immobilized anaerobic microorganisms(IANS) and suspension anaerobic sludge(ANS).It tested degradation of effluent in TNT production by making intermittent experiments. It tested the treating results of effluent in TNT production and the process of starting and treating of the system in which the immobilized anaerobic sludge balls were used as filler and upflow anaerobic sludge bed was used as reactor.The result proved that the quantity of gas production and its increase rate in the system with IANS were higher than that with ANS on the similar conditions. The volume load ratio, sludge ratio and ratio of quantity of gas production of sludge per unit of IANS and ANS were about 2. This proved that biodegrability of IANSsystem was higher than that of ANS system. In intermittent experiments, the removal rate of TNT and CODCr could reach to 98.3% and 86.7% respectively. The biochemical degradability of TNT in the actual production effluent reached to 89.9%. When the system ran stably the removal rate of CODCr was between 50.8% to 70.6%, the rate of TNT was between 83.0% to 93.0% and the rate of SS was between 88.6% to 91.4%. The concentrations of VFA and pH in the treated wastewater kept stable. The processes of upflow anaerobic sludge bed system, in which the immobilized anaerobic sludge balls were used as filler, were fast to be started, stable to be operated and much less sludge was produced.The main innovations in the research work are:â‘  making immobilized anaerobic sludge balls with chitosan as carrier by embedding technology;â‘¡ tested the whole processe of system starting and operating using immobilized anaerobic sludge balls as filler and using upflow anaerobic sludge bed as reactor.These innovations have not been reported yet. The research results provide a foundation for deeper theoretical research and practice in using the microbion immobilization technology to process hardly degradated organic wastewater.