How to dispose the sewage sludge in a harmless way at low cost and utilize sewage sludge as resource has been an urgent problem to be solved. On the basis of the principle of heat and mass transfer

this paper firstly establishes the thermodynamic model of the sewage sludge drying process. Then

it proposes the comprehensive evaluation criterion of the sewage sludge drying process

which can assess the consumed heat and power in the drying process from the viewpoint of the second law of thermodynamics. Finally

the thermodynamic performance of the proposed system integrating sewage sludge drying process and coal-fired power plant is assessed. The results show that

when integrating with the coal-fired power plant and under the premise of the required heat transfer temperature difference is ensured

the comprehensive energy consumption reaches the lowest when the ratio of air to sewage sludge is 3.32. Compared with the reference case

the net power output and net thermal efficiency of the hybrid system are promoted. Furthermore

sensitivity analysis reveals that

the increase of pressure drop of the dryer will result in an increment of comprehensive energy consumption of drying process

and the system net thermal efficiency drops when considering the decrease of boiler efficiency owing to the co-incineration of coal and sewage sludge.