The effect of calcium on the treatment of fresh leachate in an expanded granular sludge bed bioreactor

• Published in: Bioresource technology Vol. 102; no. 9; pp. 5466 - 5472
• Main Authors: Liu, Jianyong, Hu, Jun, Zhong, Jiangping, Luo, Jinghuan, Zhao, Aihua, Liu, Feng, Hong, Ruijing, Qian, Guangren, Xu, Zhi Ping
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Kidlington Elsevier Ltd 01.05.2011; Elsevier
• Subjects: Anaerobic treatment; Anaerobiosis; analysis; Applied sciences; Biodegradation, Environmental; Biological and medical sciences; Biological Oxygen Demand Analysis; Bioreactors; Biotechnology; Calcium; Calcium - chemistry; Calcium accumulation; calcium carbonate; chemical oxygen demand; Chemical Precipitation; chemistry; Crack opening displacement; EGSB bioreactor; Exact sciences and technology; Fresh leachate; Fundamental and applied biological sciences. Psychology; Granular materials; Granule settling; Granules; instrumentation; isolation & purification; leachates; Methane; Methane - analysis; Methods. Procedures. Technologies; Nitrogen; Nitrogen - isolation & purification; Oxygen demand; phosphates; Phosphorus; Phosphorus - isolation & purification; Pollution; Precipitation; Sewage; Sewage - chemistry; Sludge; Specific methanogenic activity; Various methods and equipments; Volatilization; Waste Disposal, Fluid; Wastes; Water Pollutants, Chemical; Water Pollutants, Chemical - isolation & purification; Water Purification; Water Purification - instrumentation; Calcium accumulation; Specific methanogenic activity; EGSB bioreactor; Fresh leachate; Granule settling; Calcium; Specific activity; Bioreactor; Methanogenesis; Wastes; Granule; Leachate; Granular bed
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2010.11.056

This research investigated the calcium effect on the anaerobic treatment of fresh leachate in an expanded granular sludge bed (EGSB) bioreactor under mesophilic conditions. The observations show that the bioreactor, inoculated with anaerobic granular sludge, can be started up only in about 40 days for the treatment of calcium-containing fresh leachate with chemical oxygen demand (COD) removal efficiency above 90% and organic loading rate up to 72.84 kg COD/m 3 day. The calcium accumulation onto the granules was monotonically related to the calcium concentration, accounting for 17–18 wt.% of Ca in the suspended solid in the form of calcium carbonate, phosphates/phosphonates and carboxylates. The mineral formation significantly increased the granule settling velocity (by ∼50%) and the suspended solid concentration (by ∼100%). However, the effect of calcium precipitation on the specific methanogenic activity and the CH 4 production rate was complex, first positive during the start-up but later on negative.