水热碳化技术用于污泥处理处置前景分析  

Perspectives on Hydrothermal Carbonization Technology for Municipal Sludge Treatment and Disposal

作　　者：许劲[1,2] 徐军[1,2] 吕秋颖 范准 唐琦 李杨[1,2] 方俊华 XU Jin;XU Jun;LU Qiu-ying;FAN Zhun;TANG Qi;LI Yang;FANG Jun-hua(School of Environment and Ecology,Chorgqing University,Chongqing 400045,China;Key Laboratory of the Three Gorges Reservoir Region's Eeological Enironment,Chongqing Unirersity,Chongqing 400045,China)

机构地区：[1]重庆大学环境与生态学院,重庆400045 [2]重庆大学三峡库区生态环境教育部重点实验室,重庆400045

出　　处：《中国给水排水》2020年第16期54-56,57-59,共6页China Water & Wastewater

基　　金：国家水体污染控制与治理科技重大专项(2017ZX07401001-02);中央高校基本科研业务费资助项目(2019CDCGCH339)。

摘　　要：由于土地利用受阻、填埋空间有限以及二次污染等问题,污泥处理处置主流技术路线在国内面临困境,所以亟需从科学方法角度分析其可行路径。根据污泥处置途径对含水率的要求,建议当污泥水分存在时先去除或转化有机物;同时从生物质转化技术角度进行了可行性分析,其中水热碳化技术具有处理对象无需干燥、易与其他废弃生物质及技术组合、产物无菌、磷回收率高等优势。污泥基水热生物炭有固-固转化和液相晶核转化两条形成途径,其热值与煤相当,脱水性能良好、磷富集回收率高、可固定重金属,其碳骨架作为氮磷缓释载体可增加土壤肥力,而且与无机肥减量配施兼具农业经济价值和环境生态效益。污泥水热碳化处理可实现污泥减量化、稳定化、无害化和资源化,推荐污泥处理处置方案为重力浓缩/机械脱水+水热碳化,该工艺适用于原位与分散处理,同时建议采用低温(150~170℃)水热碳化以避免高温下污泥发生美拉德反应生成溶解性难降解有机物,其液体产物可作为有效碳源补充到低碳源污水厂进水。Due to hindered agriculture use and limited space for landfill as well as secondary pollution,the mainstream technology route of municipal sludge treatment and disposal is facing difficulties in China.So it is urgent to analyze its feasible path from scientific approaches.According to requirements of moisture content in sludge disposal process,it is suggested to remove or transform organic matter when sludge moisture exists.Meanwhile,the feasibility analysis is carried out from the point of view of biomass conversion technology.Among them,hydrothermal carbonization(HTC)technology has the advantages of treating object without drying,easy to combine with other waste biomass and technology,sterile product and high recovery rate of phosphorus.Sludge-based hydrothermal biochar has two formation pathways,which are solid-solid and liquid phase nucleation transformations.It has the same calorific value as coal,good dehydration performance,high phosphorus enrichment recovery rate,and could fix heavy metals.Its carbon backbone could be used as a slow-release carrier of nitrogen and phosphorus so as to increase soil fertility.Moreover,the biochar with inorganic fertilizer reduction and application has both functions of agricultural economic value and environmental ecological benefits.Sludge HTC treatment could realize sludge reduction,stabilization,harmlessness and resource recovery.As a result,the process of gravity concentration/mechanical dehydration+HTC was taken as the recommended sludge treatment and disposal scheme,which was suitable for in situ and decentralized processing.In addition,low temperature(150-170℃)in HTC was suggested to prevent soluble refractory organics generating from Maillard reaction during high temperature,consequently,the liquid product could be used as an effective carbon source to supplement the low-carbon WWTP.

关 键 词：水热碳化 污泥处理处置 生物质转化技术 污泥基水热生物炭 

分 类 号：TU992[建筑科学—市政工程]