Reduction in greenhouse gas emissions from sludge bio-drying instead of heat drying combined with mono-incineration in China.

Journal of the Air & Waste Management Association (1995)

PubMedID: 27629354

Liu HT, Wang YW, Liu XJ, Gao D, Zheng GD, Lei M, Guo GH, Zheng HX, Kong XJ. Reduction in greenhouse gas emissions from sludge bio-drying instead of heat drying combined with mono-incineration in China. J Air Waste Manag Assoc. 2016;.
Sludge is an important source of greenhouse gas (GHG) emissions, both in the form of direct process emissions and as a result of indirect carbon-derived energy consumption during processing. In this study, the carbon budgets of two sludge disposal processes at two well-known sludge disposal sites in China (bio-drying and heat drying pre-treatments, both followed by mono-incineration) were quantified and compared. Total GHG emissions from heat drying combined with mono-incineration were 0. 1731 tCO2e·t(-1), while 0. 0882 tCO2e·t(-1) were emitted from bio-drying combined with mono-incineration. Based on these findings, a significant reduction (approximately 50%) in total GHG emissions was obtained by bio-drying instead of heat drying prior to sludge incineration. Sludge treatment results in direct and indirect greenhouse gas (GHG) emissions. Moisture reduction followed by incineration is commonly used to dispose of sludge in China; however, few studies have compared the effects of different drying pretreatment options on GHG emissions during such processes. Therefore, in this study, the carbon budgets of sludge incineration were analyzed and compared following different pretreatment drying technologies (bio-drying and heat drying). THE RESULTS
indicate that bio-drying combined with incineration generated approximately half of the GHG emissions as heat drying followed by incineration.Accordingly, bio-drying may represent a more environment friendly sludge pre-treatment prior to incineration.