Design and simulation of an appropriate slaughterhouse wastewater treatment and recycling system for sanitary uses :

Abstract

The abattoir (meat processing industry) is one of the Largest consumers of total freshwater used in the agricultural and livestock industry worldwide. Abattoir produce large amounts of slaughterhouse wastewater (SWW) because of the slaughtering process and Cleaning of facilities SWWs need significant treatment for a sustainable and safe discharge to the environment due to the high content of organics and nutrients. Due to the percentage of wash wastewater discharged, there is a lot of wash wastewater that needs to be recycled and reused. In Iganga municipality, abattoir wash wastewater is discharged to the environment without prior treatment hence polluting the environment and wasted water. Poor management of wash wastewater at the abattoir has led to poor sanitation within and around it, has also led to increased disposed wastewater volume, has also led to pollution of domestic water sources like wells, boreholes etc., has also led to increased bad smell and odors misuse. The purpose of the design project was to design a wash wastewater recycling system that would help to manage the wash wastewater and also supplement on the available source of water. Wash wastewater quality was determined by collecting samples and taking them to the laboratory for analysis, generated quantity of wash wastewater was determined depending on the total water consumption by the abattoir. Design of various components of the wash wastewater treatment and recycling system was done using the given relevant formulas and equation. From the research, wash wastewater being generated currently was 2636 litres per day and projecting for a month 73808Iitres per day was estimated. The wash wastewater being discharged showed poor physical biological characteristics and thus needs treatment before reuse. Diversion pipes, collection chamber was sized then treatment units where one sedimentation tank, Aerated lagoon, Disinfectant tank, then distribution clear tank, pumping unit, distribution pipe and head tank were sized. An economic evaluation of the system Was done using benefit cost ratio approach and it was found to be 1.35 this; meant that the project was feasible and thus should be implemented at the abattoir to curb the problem of poor wastewater management. The possibility of using the preliminary; primary; secondary and tertiary processes for slaughterhouse wastewater treatment was investigated. The results showed that the processes could be an efficient purification method. Its application resulted in about 99% and 98% removal of total suspended solids and total dissolved solids respectively. The removal efficiency of COD and BOD5 exceeded 94%.