Feasibility study of Kood-e Aali-e Gillan compost factory`s leachate treatment by anaerobic methods (downflow and upflow)

Subject Areas : environmental management

Amir Hesam Hasani ¹ , Nader Mokhtarani ² , Asghar Bayatfard ³

1 - Faculty of Energy and Environment, Science and Campus ,Azad University of Tehran
2 - Faculty of Engineering Environmental, Eng. Division Tarbiat Modares University
3 - Faculty of Energy and Environment, Science and Research Branch,Campus ,Azad University of Tehran

Received: 2006-11-11 Accepted : 2007-04-15 Published : 2009-09-23

Keywords: Leachate, compost factory, anaerobic reactor, media, Kood-e Aali-e Gillan Company,

Abstract :

There are different methods for the treatment of strong wastewater. The aim of the present study was the treatability of compost leachate by anaerobic method. The researchers did a literature review but found little about anaerobic filters. Then, the study started and lasted for 12 months. Finally, the Excel software was used to analyze the results and draw the related diagram. Construction blocks of clay with the effective area of 87 m2 were used as media in UAFB reactors. Thirty-three percent of the height of each reactor was filled with the media. The sequencing of reactors was downflow and upflow. The average concentration of the inlet COD of the reactors was 85000mg/l, while the highest and lowest COD concentrations in the reactors were 140000mg/l and 39400mg/l, respectively. The pH of the inlet leachate was neutralized by Ca (OH)2 and the average temperature of the inlet leachate was 35o C. The parameters studied in this research were COD removal, loading, variation of pH with different loadings, and critical temperature of anaerobic reactor. The results of the study are as follows: The highest COD removal efficiency (97%) of reactors in the treatment of leachate was obtained in COD concentration of 75000mg/l, HRT of 11 hours, and OLR of 46 kg COD/m3.d. The highest OLR inlet to anaerobic reactors was 11.1kg COD/m3.d. At this time, the inlet COD concentration in the reactors was 75000mg/l with the COD removal efficiency of 86.6%. The lowest and highest hydraulic rates of anaerobic reactors were 1m3/d and 40m3/d, respectively. Operating fixed film reactors with low concentrations of mlss (mlss =400mg/l) was possible. It was done in this research and COD removal increased together with an increase in mlss. Finally, COD removal reached 97.7%. In this study, the critical temperature was 19o C. As the temperature lowered, the efficiency of COD removal sharply decreased and reached 4-5%. Fixed film reactors are able to treat strong wastewater (leachate in this research) with the COD concentration of 140000mg/l.