A Feasible scheme for slaughterhouse wastewater treatment using an anaerobic digestion batch reactor followed by an aerobic treatment stage

Abstract

The sustainable management of slaughterhouse wastewater calls for feasible treatment technologies to protect the environment and public wastewater treatment facilities. The technology of an up-flow anaerobic sludge blanket provides an adequate procedural condition for the reduction of carbonaceous matter from the high organic wastewater resulting from the slaughterhouses. The scope of this research included a rapid review of current treatment technologies for slaughterhouse wastewaters and an investigation of the treatment efficiency of an aerobic stage after a pre-anaerobic treatment in a batch system. A batch reactor system of 1 m3 volume with a mixer was developed. The anaerobic stage of the batch reactor was initiated using 400 L of fresh slaughterhouse wastewater mixed with 40 L of primary sludge. Three samples from the anaerobic batch reactor were collected at a 10 d interval and then five samples were collected from the reactor after being under the aerobic condition at a 4 d interval. The removal efficiency of biochemical oxygen demand, chemical oxygen demand, total Kjeldahl nitrogen, and PO4 was 25%, 62%, 42%, and 9% in 30 d, respectively. After the start of the aeration system, the removal efficiency was improved up to 94%, 69%, and 93%, respectively, except for PO4 which showed high variations within the sampling periods.