An integrated process involved coagulation and anaerobic sequencing batch reactor (ASBR) to remove organic substances in mechanical dewatering wastewater from municipal garbage

Abstract

Mechanical dewatering wastewater (MDW) from municipal garbage is a mixture that is quickly separated from raw domestic waste by high-pressure extrusion without a sump fermentation process. Alkali treatment-coagulation sedimentation-ASBR treatment technology was adopted in this study to treat SS and organic matter. The results showed that the optimum pH of the alkali treatment was 9.0, polyaluminum chloride (PAC) was the best coagulant for the coagulation and sedimentation of MDW. The optimal working condition were gotten with a Ca(OH)2 dosage of 200 mg/L, a pH of 10.0, and a PAC dosage of 800 mg/L, under the intermittent stirring mode of 250 r/min for 1 min and then 50 r/min for 10 min. Perfect domestication effect of the ASBR was achieved under medium temperature for 28 days. The optimum conditions for ASBR were determined as follows: temperature was 35 °C, and organic loading rate (OLR) was 6 kg COD/ (L·d). Analysis of the microbial community structure succession showed that the success rate of anaerobic microorganisms in medium temperature ASBR was fast and adaptable. This study provides technical support for the actual application.