焚烧法作为实现我国污泥快速减量化、无害化处置的主流方式而得到广泛应用，而在“双碳”减排目标的推动下，燃煤耦合污泥焚烧发电技术能有效实现燃煤领域的低碳减排和污泥的清洁焚烧处置。本文总结了污泥基本理化性质、水分赋存形态、煤质指标和不同干化技术，对比分析了湿污泥直接掺烧、烟气直接干化污泥后掺烧和饱和蒸汽间接干化污泥后掺烧这三种技术路线的优缺点，并对我国燃煤耦合污泥发电典型工程项目进行介绍。实践表明“干化+掺烧”的技术路线能在保证燃烧热稳定性的基础上实现较大的污泥处置量，只要污泥的掺烧比例能控制在较佳范围内，燃煤机组既能保证较高的燃烧热效率，又能满足常规污染物、重金属和二噁英等污染物的排放标准。

 Incineration is widely used as the mainstream way to achieve the rapid reduction and harmless disposal of sludge in China,and with the aim of "double carbon" emission reduction plan,co-combustion of sludge with coal can realize the carbon emission reduction and the clean incineration of sludge. However,there are still many problems in slagging,combustion pollutant emission and technical economy. The basic physical and chemical characteristics,water content distribution,coal quality index,and drying technologies of sludge were analyzed. The advantages and disadvantages of three technical routes of co-combustion of sludge with coal,i.e.,direct co-combustion,co-combustion of sludge dried directly by flue gas,and co-combustion of sludge dried indirectly by steam,were thoroughly analyzed based on the typical co-combustion projects. The results show that direct co-combustion of wet sludge is faced with poor combustion stability and low disposal capacity,and the combination of drying and co-combustion can achieve a large disposal capacity and ensure the combustion stability. Considering the problems of high dust explosion risk and large demand for flue gas in the direct drying of sludge by flue gas,co-combustion of sludge dried indirectly by steam is a better choice with good combustion performance. Among sludge indirect-drying technologies,paddle drying and rotary disc drying have high thermal efficiency,low dust production,and small floor area. Due to the existence of viscosity during sludge drying,it is necessary to select an appropriate drying model to analyze the heat and mass transfer process. Based on the operation practice of typical co-combustion projects in China,it is found that when the blending ratio of sludge is well controlled,co-combustion technology can not only ensure high combustion thermal efficiency,but also meet the emission standards of pollutants including conventional pollutants,heavy metals and dioxins. In terms of national policy,it is urgent to clarify and refine corresponding policies,e.g.,the pollutant emission standard,power generation subsidy standard,and carbon emission reduction accounting standard,to promote the development of co-combustion of sludge with coal.

0 引言

1 污泥主要理化性质、燃烧特性及干化技术

   1.1 污泥主要燃料指标、元素组成及燃烧特性

   1.2 污泥水分赋存形态

   1.3 污泥干化技术

2 燃煤耦合发电工艺

   2.1 耦合焚烧工艺路线发电技术对比

   2.2 耦合污泥发电对燃煤机组的影响

3 燃煤耦合污泥焚烧工程案例分析

4 结语及展望