Title of article :
Comparing the influence of low power ultrasonic and microwave pre-treatments on the solubilisation and semi-continuous anaerobic digestion of waste activated sludge
Author/Authors :
Lise and Houtmeyers، نويسنده , , Sofie and Degrève، نويسنده , , Jan and Willems، نويسنده , , Kris and Dewil، نويسنده , , Raf and Appels، نويسنده , , Lise، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2014
Abstract :
Anaerobic digestion is a well-known technique for the recovery of energy from waste sludge. Pre-treatment methods are useful tools to improve the biodegradability of the sludge and to enhance the digestion efficiency. In this study, an ultrasound (US) and a microwave (MW) pre-treatment were compared in a long-term digestion experiment, using 3 small pilot scale semi-continuous digesters (SRT = 20 days). A specific energy of 96 kJ/kg sludge was applied, hence enabling to compare the effectiveness of both pre-treatment methods towards sludge solubilisation and biogas production enhancement. Total and volatile solids (TS and VS), COD, carbohydrates and proteins were monitored throughout the digestion experiment. It was seen that US was most effective in COD solubilisation. The average biogas increment was 20% for the microwave pre-treatment and 27% for the ultrasonic pre-treatment. However, this additional biogas production did not outweigh the energy consumed by the pre-treatment, leading to a negative energy balance.
Keywords :
Waste activated sludge , Anaerobic digestion , Microwave pre-treatment , Ultrasound pre-treatment , Pilot scale
Journal title :
Bioresource Technology
Journal title :
Bioresource Technology