ISSN 2756-3804
International Journal of Irrigation and Water Management ISSN 5423-5294 Vol. 5 (9), pp. 001-013, September, 2018. © International Scholars Journals
Full Length Research Paper
The use of the purple non sulfur bacterium isolate P1 and fermented pineapple extract to treat latex rubber sheet wastewater for possible use as irrigation water
Duangporn Kantachote1,3*, Nastee Kornochalert1 and Sumate Chaiprapat2,3
1Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai 90112, Thailand.
2Department of Civil Engineering, Faculty of Engineering, Prince of Songkla University, Hat Yai 90112, Thailand.
3National Center of Excellence for Environmental and Hazardous Waste Management-Satellite Center at Prince of Songkla University, Hat Yai 90112, Thailand.
Accepted 22 March, 2018
Abstract
A central composite design using two variables (concentrations of isolate P1 and Fermented Pineapple Extract (FPE) each at three levels was used to study their effects on the treatment efficiency of latex rubber sheet wastewater under microaerobic-light conditions. The optimum combination over a 72 h period consisted of 3% P1 and 0.13% FPE and resulted in the removal of 80% Chemical Oxygen Demand (COD), 82% Suspended Solids (SS) and 85% Un-ionized Hydrogen Sulfide: H2S in wastewater (UHS). The selected experimental condition was then verified by varying the retention times. A 96 h retention time gave the highest treatment efficiency with a 92% reduction of COD, 87% SS and 83% UHS and the effluent met both standards for industrial effluent discharge and crop irrigation. This effluent in its undiluted and diluted between 1: 25-1: 200 showed no phytotoxicity and also stimulated rice seed germination based on a germination index when compared with distilled water. Addition of 3% P1 into the raw wastewater either alone or in combination with 0.13% FPE yielded an effluent that passed the standard guidelines within 72 h, while with FPE alone a 96 h retention time was required. Based on morphological, physiological and biochemical properties, the isolate P1 was identified as Rhodopseudomonas palustris.
Key words: Fermented plant extracts, hydrogen sulfide, latex rubber wastewater, purple nonsulfur bacteria, response surface method, wastewater treatment.