热解炭化技术在污泥处置中的应用与展望

APPLICATION AND PROSPECTS OF PYROLYSIS CARBONIZATION TECHNOLOGY IN SLUDGE TREATMENT

随着我国城市化水平的不断提升,污水厂产生的污泥量目前已位居世界首位。作为一项新兴处理技术,污泥热解炭化有着低污染、低排放、高资源回收性的特点,可助力城镇供排水系统实现节能减碳与绿色发展目标。对我国热解技术的政策发展历程及标准化工作进行了总结,系统性综述了影响污泥热解炭化过程的关键因子及响应机制,并对热解炭化过程中污染物的迁移转化规律进行了探讨,明确了热解炭化可实现重金属的钝化、抗生素抗性基因和微塑料等新污染物的削减。热解炭化前合适的预处理方式可以减少污泥热解过程中NO_(x)、SO_(x)等污染物前驱体的生成。微波辅助热解及污泥与其他生物质共热解的相关研究,为污泥炭化提供了创新思路。污泥热解炭经改性处理可用作吸附剂、催化剂和土壤改良剂等高值化资源产品。我国目前已经建设起诸多污泥热解炭化的典型工程案例,对于污泥炭化的进一步推广具有重要指导意义。但现有污泥热解装备仍存在传质效率低等问题,亟需进一步创新研发,标准规范方面需要进一步完善相关的运行与环评导则、污染物控制与产物质量标准、价格机制等。

As urbanization in China continues to advance,the volume of sewage sludge produced by wastewater treatment plants ranks among the highest globally.As an emerging treatment technology,sludge thermal pyrolysis carbonization offers characteristics of low pollution,low emissions,and high resource recovery potential,thus aiding in the achievement of energy efficiency,carbon reduction,and sustainable development goals for urban water supply and drainage systems.This paper summarizes the policy development trajectory and standardization efforts pertaining to thermal pyrolysis technology in China.It systematically reviews the key factors and response mechanisms influencing the process of sludge thermal pyrolysis carbonization and explores the migration and transformation patterns of pollutants during this process.It is elucidated that thermal pyrolysis carbonization can effectively passivate heavy metals and reduce emerging pollutants,such as antibiotic-resistant genes and microplastics.Appropriate pretreatment methods prior to thermal pyrolysis carbonization can mitigate the generation of precursor pollutants,such as NO_(x) and SO_(x) during sludge carbonization.Research on microwave-assisted pyrolysis and co-pyrolysis of sludge with other biomasses provides innovative approaches for sludge carbonization.Modified sludge subjected to thermal pyrolysis carbonization can serve as high-value resource products,including adsorbents,catalysts,and soil amendments.China has already established numerous exemplary engineering projects involving sludge thermal pyrolysis carbonization,which hold significant guidance for further advancement of sludge carbonization practices.However,the existing sludge thermal pyrolysis equipment still faces challenges such as low mass transfer efficiency,necessitating further innovation and development.Moreover,in terms of standardization,there is a need for further refinement of related operational and environmental assessment guidelines,pollutant control measures,product quality standards and pricing mechanisms.