It can effectively improve the efficiency of sludge treatment when optimizing exergy flow distribution of the sludge drying and incineration system's energy.Taking a domestic sludge semi-drying incineration system as the research object

the exergy flow analysis method was applied to establish the exergy flow model of this system and divide it into three parts

the fluidized bed incinerator

waste heat boiler and drying mixing device.Through theoretical analysis under different conditions

the changing rules of exergy utilization indexes of this system were discussed.The results show that

when the moisture content of sludge into the furnace was 60%

the exergy efficiency of the incinerator

waste heat boiler system and drying mixing device was 46.56%

32.41% and 53.03%

respectively.When the moisture content of sludge into the furnace reduced to 50%

the exergy efficiency of the incinerator reached high up to 53.08%

that of the waste heat boiler system reduced to 23.10% but with product exergy growth by 9.58%

that of the drying mixing device decreased to 51.93% but with the product growth by 8.23%.Although reducing the moisture content in the sludge into the furnace increased the exergy loss

but the total product exergy of each system and the exergy efficiency of the incinerator increased.The results can provide a theoretical reference for design and operation optimization of municipal sludge semi-drying incineration systems.