الفهرس | Only 14 pages are availabe for public view |
Abstract The aim of the present study is the development and testing of an integrated low cost decentralized technology for domestic wastewater treatment that can be applied in small communities and/or rural areas. The treatment system consists of treatment of raw wastewater with EM1for 20 days incubation period at concentration 5ml of EM1to 1liter of wastewater followed by treatment with different slices of corn to improve the treatment .Complete physico-chemical as well as biological examinations (bacteriological ) in raw wastewater and treated wastewater with EM1and corn. Different doses of activated EM1 were used (5, 10, 50, and 100 ml per liter of sewage water) in the treatment to know the best concentration and the best period for treatment.The average value of COD was 185.5 mg/l,BOD was111.3 mg\L, DO was 2.9 mg/l,TDS was592.917 mg\L,TSS was261.83 mg\L,TSwas 854.747 mg/l, PO4was7.1mg\L, NO3 was 8.35 mg\L, Sulphate was 81.83 mg\L ,Ammonia was 10.82 mg\L, and the average count of Total and fecal coliform were115×102 and893MPN/100ml raspectively after 20 days of incubation at concentration 5ml of EM1 to 1liter of wastewater. Using of the slices and powder of roasted and not roasted corn in wastewater treatment gave good results in treatment of wastewater and made it within international standards and making wastewater reused again. Using agriculture residue (corn or maize) to improve the treatment after knowing the best concentration of EM1 (5ml\l after 20 days) by different size and shapes,The average value of COD was 42.2mg/l,BOD was15.3 mg\L, DO was 3.43mg/l,TDS was 385.2mg\L,TSS was 80.5 mg\L,TSwas 465.7 mg/l, PO4was1.8mg\L, NO3 was 0.15 mg\L, Sulphate was 69 mg\L ,Ammonia was7 mg\L, and the average count of Total and fecal coliform were 14.9×102 and 9.8×102 MPN/100ml raspectively . Results show that wastewater with EM1 gives good results, thus corn can remove the brown color of wastewater and EM1 and the bad odors of the wastewater. Acute toxicity testing for the raw and treated wastewater was carried out using Daphnia magna as a test organism. Toxicity testing using the test organism Daphnia magna proved the efficiency of the studied treatment system where mortality decreased from 100 % in the raw wastewater to 20 % during treatment with EM1 for 20 days followed wit corn. The results of the present study indicated that using agriculture wastes with EM1 for 20 days incubation period can treat wastewater and making it suitable to be used for fish culture. The Nile tilapia Oreochromis niloticus (Linnaeus) fingerlings and the colored catfish, Clarias batrachus (Scopoli) were grown in this treated water. The survival rates of Nile tilapia were higher in treated wastewater with EM1for 20days followed with corn (45%).followed by treated wastewater with EM1only (30%) followed by treated wastewater with corn only (20%) and reached to zero in untreated wastewater. Survival rates of colored catfish were higher in treated wastewater with EM1for 20days followed with corn (60%) followed by treated wastewater with EM1 (50%) followed by treated wastewater with corn only (40%) and reached to 35% in untreated wastewater. The total coliform and fecal coliform in cat fish organs were highest in the gills, followed by intestine and finally the muscles and aslo in Nile tilapia organs. Keywords: domestic wastewater, biological treatment, reuse, effective microorganism, agriculture residue, small communities. |