Studies of ultrasound disintegration of residual sludge and its energy consumption in water treatment of petrochemical plant

Abstract

To investigate the influence of ultrasound pretreatment on sludge anaerobic digestion, the ultrasound disintegration of residual sludge in water treatment of petrochemical plant was studied, and the mechanisms of ultrasound and medium were introduced. Experimental results indicate that ultrasound cavitation induces the rise of sludge temperature, which improves ultrasound disintegration on sludge. U1trasound pretreatment can advance observably the quantity of chemical oxygen demand in sludge supernatant fluid (SCOD), which increases with ultrasound intensity and sonication time. The degree of ultrasound disintegration increases with the specific energy input. When the specific energy input is l0 000 kJ/kg of total dry solids, the degree of ultrasonic sludge disintegration reaches 40%.

Keywords

residual sludge, chemical oxygen demand, ultrasonic cavitation, specific energy consumption