Pretreatment methods as a means of boosting methane production from sewage sludge and its mixtures with grease trap sludge

Abstract

Abstract.The main objective of this study was to determine the applicability of the selected pretreatment methods as a means of intensification of methane production from sewage sludge as well as its mixtures with grease trap sludge. The addition of the fat rich material to the digester treating sewage sludge resulted in an increased methane yield as well as volatile solids (VS) removal of up to 36% (from 134.75 mL/g VS to 182.84 mL/g VS). Furthermore, thermochemical pretreatment of the co-digestion mixture resulted in an approximately 76% higher methane yield as compared to the untreated sewage sludge. The energy balance showed that, for both materials ultrasonic pretreatment and thermochemical pretreatment has an energy self-sufficiency. All of the tested models fit the experimental data with coefficients of determination higher than 0.96.

Effect of Ca(OH)2 on the Release Characteristics of HCl during Sludge Combustion

“…Sewage sludge can come from the domestic sewage treatment process, 1 , 2 and the average annual growth rate of China’s total sludge production was 13% during 2007–2013 years. 3 Because of the large amount of energy required, the cost of sludge treatment accounts for approximately 50% of the total operating cost of the sewage treatment plant.…”

“…Sewage sludge can come from the domestic sewage treatment process, , and the average annual growth rate of China’s total sludge production was 13% during 2007–2013 years . Because of the large amount of energy required, the cost of sludge treatment accounts for approximately 50% of the total operating cost of the sewage treatment plant. , The disposal and recycling of sludge have attracted much attention because of its serious risk of negative ecological and environmental impacts. − There are many disposal methods for sludge disposal, − and combustion is gaining more and more attention because of its unique advantages. , Although sludge combustion has many advantages, the problem of flue gas pollution caused by combustion has always been concerned, especially dioxins (PCDD/Fs) and chlorobenzenes (CBs, dioxin precursors).…”