剩余污泥中PPCPs量化评价方法研究

Study on Quantitatively Assessing Method of PPCPs in Excess Sludge

药物和个人护理品(Pharmaceutical and Personal Care Products,PPCPs)作为一种新兴痕量有机污染物已开始备受国际关注。PPCPs通过水环境迁移与生物积累等方式几乎已遍布整个地球,它们会对人类健康及其他生物生长造成潜在危害。PPCPs一般随污水收集而进入污水处理厂;但因其难以生物降解而很难被分解;除微量PPCPs可通过逸散、光降解等方式释放大气外,大部分PPCPs要么随出水(直接)进入环境、要么被吸附于活性污泥表面(随后可能间接进入环境)。因此,需要对污泥吸附PPCPs进行量化表征。借助固-液分配系数(K_d值),建立了一种简便、快速预测PPCPs的计算方法。通过广泛收集现有文献中PPCPs的K_d值,结合北京地区污水处理厂的真实情况,分别计算出剩余污泥中33种常见PPCPs含量。尽管大多数PPCPs在剩余污泥中的吸附率不是很高(≤20%),但少数PPCPs向污泥中的绝对转移量不可小觑,高达全部33种PPCPs向污泥中总转移量的88%。避免污泥中PPCPs再次进入环境,污泥焚烧是一种有效途径。

As an emerging trace organic contaminant,pharmaceutical and personal care products (PPCPs) have been paid more and more attention from the world. PPCPs have been spreading almost all over the world through migration in water environment and bioaccumulation in ecology,which could put a healthy threat to human beings and other creatures. PPCPs usually enters wastewater treatment plants (WWTPs) along with collected sewage. Due to the difficulty in the biodegradation for PPCPs,it is hardly be removed via biological process. Except that trace PPCPs can release into atmosphere by escape and photodegradation,most PPCPs either enters the environment with effluent (directly) or is adsorbed on the surface of activated sludge (which may enter the environment indirectly). Therefore,it is necessary to quantitatively characterize the adsorption of PPCPs by sludge. In this study,a simple and fast predicting method on the amount of PPCPs adsorbed in excess sludge is established,based on the solid-liquid partition coefficient (K_d). By extensively collecting K_dvalues of PPCPs and applying Beijing’s practical data,33 common PPCPs contents in excess sludge were calculated respectively. Although the adsorbing efficiencies are not very high (≤20%) for most of PPCPs,the absolute transfer amount of a few PPCPs to sludge can not be underestimated,up to 88% of the total transfer amount of all 33 kinds of PPCPs to sludge. To prevent PPCPs from entering the environment again,sludge incineration is an effective way.