垃圾焚烧厂渗滤液预处理工艺研究

STUDY ON REFUSE INCINERATION PLANT LEACHATE PRETREATMENT TECHNOLGY

为了探讨垃圾焚烧厂渗滤液与城市污水合并处理的可能性,采用混凝沉淀-过滤-吹脱联合工艺对垃圾焚烧厂渗滤液进行预处理。实验结果表明:当Fe Cl3投加量控制在1‰,Ca O投加量控制在20 g/L时,COD、TN、NH+4-N和TP的去除率可分别达到6.0%、33.3%、32.0%和71.3%;混凝后渗滤液在50℃下吹脱6 h,TN和NH+4-N去除率分别提高到83.9%和91.4%。预处理后的渗滤液与城市污水按体积比为1∶250混合时,混合污水的C/N和C/P由2.4和27.7分别提高到3.7和45.5。表明垃圾焚烧厂渗滤液经过预处理后,可以作为城市污水反硝化时的补充碳源,与城市污水合并处理具有很好的工程应用前景。

A combined process of coagulation-filtration-air stripping was applied to remove pollutants from leachate in a fullscale municipal refuse incineration plant in attempt to assess the feasibility of joint-treatment of leachate and municipal sewage.The results showed that the removal rate of COD,TN,ammonium,and TP content in raw leachate reached 6. 0%,33. 3%,32. 0%,and 71. 3%,respectively,when the dosage of Fe Cl3 and CaO were kept at 1‰ and 20 g / L in coagulation process.Then,the removal rates of TN and ammonium in landfill-leachate were increased to 83. 9% and 91. 4% after air stripping for6 hours at 50 ℃. The pre-treated leachate was mixed with municipal sewage at a ratio of 1 /250,and C / N and C / P value of the mixed sewage increased from 2. 4 and 27. 7,to 3. 7 and 45. 5. Therefore,it can be inferred that the pre-treated leachate could be regarded as a potential carbon source for denitrification in the biological nitrogen removal process of municipal discharges. In view of the above,this combined process exhibits a promising application prospect in the treatment of sewage with low C / N value.