International Research Journal of Biological Sciences ___________________________________ ISSN 2278-3202 Vol. 4(3), 66-75, March (2015) Int. Res. J. Biological Sci. International Science Congress Association 66 Biological Treatment of Meat Processing Wastewater using Anaerobic Sequencing Batch Reactor (ASBR) Tansengco Myra 1 , Herrera David 1 , Tejano Judith 1 , Yao Marina 2 , Beraye Jose Ricky 1 and Esguerra Reynaldo 1 1 Environment and Biotechnology Division, Industrial Technology Development Institute, Department of Science and Technology, General Santos Avenue, Bicutan, Taguig City, 1631 Metro Manila, PHILIPPINES 2 Chemicals and Energy Division, Industrial Technology Development Institute, Department of Science and Technology, General Santos Avenue, Bicutan, Taguig City, 1631 Metro Manila, PHILIPPINES Available online at: www.isca.in, www.isca.me Received 12 th January 2015, revised 20 th February 2015, accepted 20 th March 2015 Abstract Effluents from meat processing industries contain high organic compounds and other contaminants that can cause harmful effects to the environment. Treatment of this wastewater to produce acceptable quality of effluent is therefore needed. This study aimed to determine the feasibility of using anaerobic sequencing batch reactor (ASBR) for treatment of meat processing wastewater and for biogas production. A laboratory-scale ASBR was designed and fabricated with an active volume of 10 liters (L) consisting of 60% wastewater and 40% sludge inoculum. The effects of different ASBR reaction durations were examined to determine the appropriate reaction time needed to achieve high organic removal in meat processing wastewater. Actual batch ASBR operation composed of four phases per cycle (24 hours): wastewater filling - 0.5 h, reaction -16 h, settling -7 h, and decantation -0.5 h. Post-treatment of effluent was done using granulated activated carbon. During biomethanation process in ASBR, pollutant removal was: 94% chemical oxygen demand (COD), 93% biochemical oxygen demand (BOD), 54% suspended solids, 58% turbidity, and 53% color. The concentration of COD and BOD in treated effluent was 116 mg/L and 78 mg/L, respectively. Biogas generated during the ASBR reaction was 2.7 L/day with 61% methane content. Post-treatment of effluent further reduced the concentrations of pollutants to acceptable level with 76 mg/L COD and 20 mg/L BOD. Biological treatment using ASBR and post-treatment with activated carbon was proven effective in reducing organic pollutants in meat processing wastewater. Keywords: Anaerobic sequencing batch reactor, ASBR, meat processing wastewater, biological wastewater treatment, biogas, anaerobic wastewater treatment, anaerobic digestion. Introduction Meat processing wastewater constitutes one of the major concerns of the agro-industries. Generally, meat processing wastewater contains high levels of various contaminants such as fat, suspended solids, chemical oxygen demand, biological oxygen demand, chlorides, and nitrogen 1 . Considering the standard allowable limit for effluent discharge, pollutants must be removed from these food industry wastewaters before discharging to the environment. Anaerobic digestion in high- rate reactors such as anaerobic sequencing batch reactor (ASBR) can be applied for meat processing wastewater for its high amount of organic material and it provides high chemical oxygen demand (COD) and suspended solid removal 2 . The ASBR treatment method is relatively simple to operate, economical, with flexible control, required limited manpower, generates low quantity of sludge, and produce alternative energy in the form of methane 3-7 . The technique is efficient in reducing organic matter in low to high strength wastes. An ASBR operates in a single reactor vessel with four (4) phases of operation that allows for a high throughput of material while retaining microorganisms in reactor. The four steps of a typical ASBR cycle consist of the following: i. feeding or filling, ii. reaction, iii. settling or sedimentation, and iv. decantation or withdrawal of treated effluent 3,8,9 . During the feeding and reaction steps, the reactor content is slowly stirred to allow close contact between organics and bacteria 5,10 . Biogas produced during ASBR treatment of wastewater can be utilized for cooking or heating. On the other hand, sludge by-product from the digester can serve as soil conditioner or fertilizer. The feasibility of ASBR technique for wastewater treatment was examined at laboratory-scale 6,8,11 and at the farm-scale 12 . ASBR has been used for treatment of wastewaters with high amounts of particulate organic matter such as swine manure 3,8,9 , leachate, and dairy 13 . ASBR has also been applied to treat various wastewaters such as those from abattoir/slaughterhouse 4,5,14 , meat industry 15 , olive mill plant 16 , distillery 17 , and winery plant 18 . Some studies using low strength wastewaters have also been done using ASBR 10 , as well as in decolorization of Azo dyes 19 . In the Philippines, there are no reports yet in literature on the application of ASBR in wastewater treatment. In this study, we examined the feasibility of using a lab-scale ASBR for biological treatment of meat processing wastewater and for biogas production.