Upgrading of Biological Treatment for Landfill Leachate by Nano-Membrane Systems

Treatment of landfill leachate is challenging, due to its characteristics such as age, dumping place, composition and origin of wastes. For this reason, the application of hybrid processes is helpful for complete treatment of contaminants present in the leachates. The addition of membrane operations to biological treatment technology offers new advantages for this method. For this aim, a bench-scale integrated process based on submerged aerobic MBR has been designed and fabricated. Also, Nanofiltration process as a post-treatment was used to upgrade MBR effluent. The results showed that the submerged UF-MBR system effectively removed biodegradable trace organic compounds with the average removal rate of about ۷۵% at optimum food-to- microorganism (F/M) ratio (BOD basis) of ۰.۲ gBOD/g.d under a HRT of ۲۴ h. The addition of NF process increased the treatment efficiency up to ۹۸%. The effluent COD was reduced from ۳۵۰۰ mg/l to below ۵۰ mg/l. Further, the effect of PAC addition was studied. NH۳ –N, TKN and Heavy metals removal efficiency were obtained ۹۷ ± ۲%, ۹۶ ± ۲% and ۹۹ ± ۲%, respectively.

Keywords:

Activated sludge , Powder activated carbon , Membrane bioreactor , Nanofiltration , landfill leachate treatment