In the late 90’s, the Environmental Protection Department (EPD) began to conduct studies into improving sludge treatment in Hong Kong, and they sped up progress in 2009 when it became clear that landfill space for sludge was on the verge of exhaustion. The result was the approval of a project to build a sludge treatment plant in Tuen Mun, and it would involve incineration in order to reduce the volume of the waste. Despite suggestions for the recycling of incineration ash, it seems that the ash will still be returned to landfills.
The location plan for the sludge treatment plant in Tuen Mun
The 2009 proposal can be found here.