Municipal sludge treatment and disposal;wet sludge moisture content 70%-75%;co-incineration with coal to generate electricity

Unit processes/End-of-life treatment/Waste water treatment
CN - China
Reference year: -

A 25MW co-firing power generation system is analyzed, and the sludge is directly dried by using the heat of boiler exhaust gas with a circulating fluidized bed system with an evaporation capacity of 130t/h for sludge co-burning power generation. Users of this Life Cycle Assessment data set for municipal sludge treatment and disposal should acknowledge the boundary limits from the dewatered wet sludge post mechanical compression at the sewage treatment plant to the final disposal. The functional unit is the amount of mechanical compressed 1 ton of wet sludge, which implies that all calculations and analysis should be normalized to this quantity. When applying this data, considerations for methodological consistency with regard to co-incineration emissions, transportation of sludge, and any upstream processing impacts should be included. Due to the varied nature of sewage sludge characteristics, local adaptation of the data may be necessary. Attention should also be given to regulations and environmental impacts associated with the co-incineration process.


The flue gas inlet temperature is 160°C, the flue gas outlet temperature is 85°C, and the flue gas volume is 173000m³/h. The wet sludge (70.5% moisture content) is dried to about 30% moisture content and discharged out of the drying system by using the dry material backmix drying system, and then enters the boiler and coal for co-firing power generation, the boiler efficiency is 85.58%, the sludge treatment capacity reaches 10.49t/h, and the dry sludge output after drying treatment is 4.42t/h. In order to ensure the stability of combustion in the furnace, the combustion temperature is controlled at 900~950°C, and the mass ratio of dried sludge and coal blending is 20:80.

Process type
LCI modeling approach
Multifunctional modeling
Aggregation type
Data provider
Review status
Tiangong LCI Data Working Group