Treatment of Slaughterhouse Waste by an Anaerobic Hybrid Reactor

Article type: Research Article

Authors: Farooqi, I.H. | Asifuzzaman, | Basheer, Farrukh

Affiliations: Environmental Engineering Section, Department of Civil Engineering Aligarh Muslim University, Aligarh – 202 002, India. [email protected]

Note: [] Corresponding Author

Abstract: The study was carried out to assess the feasibility of using an anaerobic hybrid reactor for the treatment of slaughterhouse wastewater. The reactor, consisting of an Upflow Anaerobic Sludge Blanket (UASB) at the bottom and an anaerobic filter at the top, was seeded with the digested sewage sludge and was initially fed with neutralized acetic acid for the activation of methanogens. Subsequently slaughterhouse waste was fed to the reactor. The experiments were conducted in five different phases by varying the hydraulic retention time (HRT) from 24 hours to 18, 12, 8 and 4 hours. Influent chemical oxygen demand (COD) was increased from 760 mg/L to a maximum of 4200 mg/L. The organic loading was progressively increased from a low of 0.76 kg COD/m^{3}d^{-1} to a maximum of 20.24 kg COD/m^{3}d^{-1}. In the first phase of the study the organic loading rate (OLR) was increased from 0.76 kg COD/m^{3}d^{-1} to 2.88 kg COD/m^{3}d^{-1} and an HRT of 24 hours was maintained. The COD removal efficiency increased from 47.3% to 96% when the reactor achieved steady state conditions. For the next three phases the OLR was increased from 2.24 kg COD/m^{3}d^{-1} to 12.6 kg COD/m^{3}d^{-1} by decreasing the HRT to 18, 12 and 8 hours. The COD removal efficiency dropped for few days but regained within a short time and was around 95% for each loading rate. However, as OLR was increased to 20.24 kg COD/m^{3}d^{-1} and HRT was decreased to four hours, the COD removal efficiency decreased (64%). It is seen that the reactor performed well over a wide range of OLR and a COD and BOD removal efficiency of 95% was achieved till an HRT of eight hours. The solids removal efficiency was 73%. It is concluded that higher organic loadings can be applied to the reactor up to an HRT of eight hours and slaughterhouse waste can be successfully treated using anaerobic hybrid reactor. However additional units in series are required to bring the BOD level to permissible values.

Keywords: Anaerobic, hybrid reactor, slaughterhouse waste

Journal: Asian Journal of Water, Environment and Pollution, vol. 6, no. 3, pp. 93-97, 2009