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Wuhan is the sixth largest city in China. One of the major environmental problems in Wuhan is the impacts of disposal of sludge from wastewater treatment plants. Today no sustainable method is applied for sludge disposal and the amount is increasing along with the increasing amount of wastewater treatment plants in the area. Sludge is a resource from which products as nutrients and energy can be retrieved. Therefore it is unsustainable to landfill the sludge as the city of Wuhan chooses to do today. This method also leads to a leakage of nutrients, toxins and other pollutants to the environment. China is recommended to follow he example of Sweden, where landfilling sludge is illegal. In Sweden, five common ways for sludge handling are now applied. These ways are as fertilizer, construction soil, and cover material, for energy production by incineration and for biogas production. 

The aim of this master thesis was to identify and evaluate the methods in Swedish sludge management and to determine the most sustainable sludge management for Wuhan. Results from a literature study and interviews both in Sweden and Wuhan showed that there are several solutions for sludge disposal and that the least sustainable method is landfill, as the city of Wuhan chooses to do today. The sludge management in Wuhan had no current policy or strategy and was not well coordinated. In addition, the know-how to implement the different methods was lacking. Swedish technology and know-how is welcome to be part of the solution according to stakeholders in Wuhan.

Co-incineration with other municipal wastes was suggested as the best solution for now due to poor sludge quality. Wuhan authorities need to identify and remove sources of pollutants to improve the sludge quality. Only then should the sludge be used as fertilizer, cover material and construction soil. This strategy will generate a better environment as well as economic profit.