A Study On The Control Of Organic Contaminants In The Anaerobic-semiaerobic Bioreactor Landfill

This paper studies the changing pattern of anaerobic-semiaerobic bioreactor landfills liquidoid, solidoid and cumulative gas generation and orthogonal test of four elements consisting of recirculation frequency, re-injection rate, adjusting leachate PH value and the leachate aeration time in order to achieve the best recirculation methodology in eliminating the organic contaminants based on this type of landfill. The research shows that:The pH value of anaerobic-semiaerobic bioreactor landfills" leachate is higher than that of anaerobic reactor, which effectively relieves the accumulation of organic acid. The apparent decrease of COD density in associative anaerobic-semiaerobic bioreactor landfills recirculation indicates that the increase of punching rate on gas tube of Semi-aerobic unit will substantially facilitate the capacity in removing the organic contaminants. After the implementation of optimal recirculation. the COD density as well as UV254value appears a decline tendency, proving the fact that it can obviously boost the speed of degradation of organic components and slash the process of acidification. During the monitoring of solidoid. it turns out the accumulative settling amount in associative reactor is higher and the organic piling-up is not evident. At last, depending on the analysis of accumulative gas production, it is suggested that the gas generation of anaerobic units is hindered. However, the improving rate of recircuiation might ease this situation.In the experiment of optimal organic degradation method, the specific recirculation conditions benefiting the degradation in anaerobic-semiaerobic bioreactor landfills are that: recirculation rate for3d per time,75%of recirculation, the adjusted PH value of8in leachate and10minutes of aeration. The reality that the prime element affecting two indicators of COD and UV254most is recirculation frequency which requires3d per time indicates that maintaining the low frequency (3d per time) during acidification is beneficial for organic contaminants elimination.According to the experimental results, this paper studies physical properties of the wastes, the structure of Anaerobic-semiaerobic bioreactor landfills, the control of leachate recirculation and pretreatment of the recirculation.It will provide the foundation and guidance on dealing with rural living wastes.