Acidic thermal post-treatment for enhancing anaerobic digestion of sewage sludge

Enhancing sewage sludge anaerobic “re-digestion” with combinations of ultrasonic, ozone and alkaline treatments

“…As the ULS and chemically aided ULS post-treatment had not been reported before, the results from this work were compared with previous studies using different posttreatment methods. Takashima (2008) obtained 130% to 200% improvement in CH 4 production when 120°C thermal post-treatment was applied; while, Takashima and Tanaka (2014) observed 172.7% -190.9% increase in sludge biodegradability when the post-treatment was conducted in pH range of 2-6. However, the methane production increase after the ULS, ULS-Ozone and ULS+ALK treatments in this work were in the range 28.3% to 48.3%.…”

Impact of hydrothermal pre-treatment on the anaerobic digestion of different solid–liquid ratio sludges and kinetic analysis

“…Various methods were investigated by many researchers, such as biological pre-treatment, 14 physical (ultrasonic, microwave et al) pre-treatment, [15][16][17] chemical (ozone oxidation, thermal and hydrolysis et al) pre-treatment. 12,[18][19][20] Such sludge pretreatment technologies are working on the principle of disintegration of cell walls and causing lysis, leading to the release of intracellular organic matter that become more easy to be used for anaerobic microorganisms. Among thermo-chemical pretreatment methods, hydrothermal pre-treatment (HTP) has signicant enhancement effect on achieving organic material degradation and anaerobic digestion performance.…”

Effects of Physico-Chemical Post-Treatments on the Semi-Continuous Anaerobic Digestion of Sewage Sludge

“…Ozone [14,15], alkaline [12], thermal [13,16], thermal/acid [17,18], and thermal/alkaline [11] was successfully applied for sludge post-treatment. There are also papers showing post-treatment were superior to pre-treatment in terms of improving the anaerobic digestion effectiveness [13,16].…”