微污染有机物去除技术优劣性LCIA/LCC评估分析

LCIA/LCC evaluation and analysis on identifying the pros and cons of organic micropollutants-removed technologies

药品和个人护理品(PPCPs)等新兴微污染有机物已广泛进入污水,而传统污水处理技术仅可去除其中有限部分.有鉴于此,许多高级处理技术被开发并应用于深度污水处理之中.但凡事均有利有弊,这些新技术会带来额外能耗、物耗,可能会形成“污染转嫁”现象,甚至出现毒性更强的中间产物.全生命周期环境影响评价(LCIA)可全面评估不同技术在处理微污染有机物过程中的综合环境影响,是深度处理技术选择的评估工具.为此,综合分析了现有文献中有关PPCPs去除6种常见技术(活性炭、紫外线、膜处理、臭氧、光芬顿、电化学)的LCIA评价结果,获得了必要的定性认知;经深度处理后出水毒性一般会降低,但因高能耗导致的高碳排则会增强温室效应,污染物转化不完全时还会出现毒性增强现象.全生命周期成本(LCC)评价结果可以反映出各种技术投资与运行成本信息.加权合并LCIA与LCC后的综合环境影响更能看出各种技术的优劣,突显出传统活性炭法因低能耗、无副产物、可再生等优点的竞争优势;同时,也让光芬顿、电化学法等技术在投资、运行费用等方面的缺陷而显得优势不足.

Emerging organic micropollutants(OMPs)such as pharmaceuticals and personal care products(PPCPs)have widely entered wastewater,but conventional technologies of wastewater treatment can partly remove them.For this reason,some advanced treatment technologies(ATTs)have been developing and even have been applied.However,everything has its pros and cons.ATTs could bring about additional energy and material consumption,resulting in the phenomena of"pollution transfer"and even toxic intermediate products.Life cycle impact assessment(LCIA)can evaluate the comprehensive environmental impact of different technologies on removing OMPs,which is a powerful tool to select ATTs.Under the circumstance,existing LCIA evaluation results on PPCPs removal by six common ATTs(activated carbon,ultraviolet,membrane,ozonation,phono-Fenton and electrochemistry)are summarized and analyzed,and thus some necessary cognitions are obtained.ATTs can reduce toxicity of OMPs in effluent to an extent,but high carbon footprints caused by high energy consumption would enhance the greenhouse effect,and sometimes the toxicity in effluent would be enhanced if pollutants’transformation is not completed.The results of life cycle cost(LCC)evaluation can offer the information of technical investment and operation cost.The comprehensive environmental impact with the weighted combination of LCIA and LCC can reflect the pros and cons of associated technologies,highlighting the competitive advantages of activated carbon due to its low energy consumption,little by-products,and renewability.At the same time,the disadvantages of photo-Fenton and electrochemical methods are displayed due to their high technical investment and operating costs.