活性污泥投加粉末活性炭的基础特性研究

Study on the Fundamental Characteris-tics of Activated Sludge fortified with Powdered Activated Carbon

在活性污泥(AS)中投加粉末活性炭(PAC)的试验结果表明,PAC不吸附氨氮,对COD的吸附容量也仅为0.0148—O.2305g COD/g PAC.而[AS+PAC]系统的反应速率常数K分别是[PAC]和[AS]系统的2.33倍和1.40倍,COD绝对去除量大于[PAC]和[AS]二者系统之和,并能明显地提高生物处理系统的有机物去除率。同时,1mg PAC还能吸附0.5—0.75mg DO;当活性污泥的PAC量占1/3,SVI可从389ml/g降至200ml/g以下;含1.5g/L PAC的污泥在投加碱式氯化铝后,污泥比阻仅为原比阻的25％,相应过滤产率提高1倍。

The results of experiments on the fundamental cha-ractristics of activated sludge (AS) fortified with powdered activated carbon (PAC) are presented. PAC does not adsorb ammnia-nitrogen and COD adsorptive capacity of PAC is only 0.0148-0.2305g COD/gPAC. However the reaction rate coefficient K of AS-PAC system is 2.33 times as great as that of PAC and 1.4 times as great as that of AS. respectively. The absolute amount of COD removed in AS-PAC is more than the sum of that in AS and PAC, so the removel rate of organics in biological treatment system is improved remarkably. In addition, lmg PAC and absorb 0.5-0.75mg dissolved oxygen. When the ratio between PAC concentration and AS concentration is 1 to 2, sludge volume index (SVI) can be reduced from 389ml/g for AS to less than 200ml/g. After being coagulated with alkali aluminum chloride the sludge containing 1.5g/LPAC shows only 25% specific resistance and a doubled filtration yield as compared with sludge without PAC. Various advantages brought by the addition of PAC in AS provide the basis for the development of treatment process and its practical application.