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1.
It is difficult to treat landfill leachate in China.Traditional biologic method and physical method always have high expenses,or cann''t reach the discharge standards.The authors use a new biologic method to treat landfill leachate,which is the Wood_microbial System from Japan.The system to be digested by 3 aeration tanks and 1 reaction tank.The comparison combine processed wool_dust broken pieces with the certain grain degree size were throw in the tanks.Dirty and organic matter are in the digest tanks through the aeration reaction and aneration reaction repeatedly.In this experiment the speed of wastewater discharge and oxygen supply has been changed, and the change of biologic system and the effect of pollutant are removed. The optimal treatment condition can be found.The experiment shows that the system has a good result,special for nitrogenous.The BOD is average to do away with the rate to amount to 90%,almost reach the second class or third class for leachate standard.But BOD loading should be not beyond 4 kg/(m 3.d),othrwise,the system will not operate in normally. 相似文献
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随着膜系统运行至一定年限,加上膜系统长期超负荷运行和膜化学清洗的不及时、不规范,都将加快膜元件的老化,造成膜元件对离子、小分子有机物等物质的截留率有所下降。膜出水COD偏高,电导率升高、颜色偏黄已成为纳滤/反渗透(NF/RO)系统运行过程中出现较频繁的问题之一,严重影响着膜系统的出水水质和出水美观度。本试验选取长沙生活垃圾渗滤液处理厂出水水质差的反渗透/纳滤处理系统为分析对象,通过冲击性投加的方式将专用NR-MRA-1000型修复剂粘附于膜表面,并24 h长期运行。试验结果表明,膜系统添加NR-MRA-1000型修复剂且运行48 h后,呈现出膜出水色度明显降低,COD截留率上升以及出水电导率下降、膜运行压力上涨等产水特征,对膜产水通量没有显著影响;且膜修复剂试验运行60 d后,膜机组相关产水性能恢复至原来的标准。 相似文献
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At present 18 wastewater treatment plants operateing in the Small towns of Three Gorge Areas of Chongqing Municipality, producing 132.95 tons surplus sludge everyday. As regards to the disposition of such numerous surplus sludge, the major disposition technique in these wastewater water treatment plants, i. e. , thickening and mechanical dewatering technique followed by feeding into the municipal solid waste landfill, seems to have a rather bad effect on the normal operation of the municipal solid waste landfill, due to the unstabilized sludge resulted from this technique of the sludge disposition and high moisture in the sludge, which is higher than 80%. This paper has paid some attention to this phenomenon. With respect to the small towns having the the municipal solid waste landfill, the techniques of mechanical dewatering, calcareousness stabilized etc. before feeding into the municipal solid waste landfill, seem to be feasible, while the composting and comprehensive utilization of sludge is available in the small towns which have no municipal solid waste landfills. 相似文献
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不同降解阶段填埋垃圾体的气体渗透特性研究 总被引:3,自引:0,他引:3
通过对不同降解阶段填埋垃圾体渗透系数的测定,研究了在不同压实密度、不同含水率条件下垃圾体渗透特性的变化情况,实验表明:1.对不同降解阶段的填埋垃圾体,新鲜垃圾及混和垃圾的渗透系数接近,腐熟垃圾明显高于前两者;随压实密度增加,其气体渗透系数均呈指数规律递减;2.随着垃圾体含水率的增加,腐熟与新鲜垃圾的渗透系数均呈线性规律递减,含水率对渗透系数的影响要远小于压实密度的影响;3.新垃圾、混合垃圾、腐熟垃圾均具有较显著的各向异性特征,在典型压实密度下,水平方向的气体渗透系数Kh为垂直方向渗透系数Kv的3.5-27.3倍。 相似文献
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With trait of late landfill leachate treated hardly, it is an effective method of enhancing biodegradability of late landfill leachate that electrolytic oxidation pretreats late landfill leachate, and it is very necessary to calculate current efficiency. Varity of organic pollutants in the late landfill leachate is studied under the electrochemical action by some tests and current efficiency under different electrolytic condition is calculated. The results show that the most high current efficiency is 34.11% when the current density is 15 mA/cm^2 and electrolytic time is 6.5 h. 相似文献