การบำบัดน้ำเสียจากอุตสาหกรรมปิโตรเคมีต้นทางโดยใช้ถังกรองไร้อากาศ / ทัยศักดิ์ ธรรมกุล = Treatment of a petrochemical wastewater from the upstream petrochemical industry using an anaerobic filter / Thaisak Thammakul
In the last decade, petrochemical industry in Thailand has grown up rapidly. As a result, petrochemical wastewater should be more concerned. This paper presents the treatment efficiency of a petrochemical wastewater by using 2 laboratory scale upflow anaerobic filters. The reactors made from acrylic material with 1.0 meter height and 0.1 meter inside diameter. The wastewater was brought from National Petrochemical Public Company Limited (NPC) which is an upstream petrochemical industry, locate at Map Ta Phut Industrial Estate, Rayong province. This study focused on treatment efficiency of anaerobic filter by varying organic loading as the variable parameter as follows: 0.58, 0.67, 0.83, 0.87, 0.95, 1.11, 1.20 and 1.78 kg.COD/m3-day. According to the experiment data, the COD removal efficiencies were 84.03, 83.31, 81.45, 84.41, 74.71, 77.18, 82.31 and 79.96%, respectively. The pH of the effluent were 7.59, 7.52, 7.46, 7.43, 7.41, 7.47, 7.44 and 7.34 and the ORP were -242, -258, -329, -270, -320, -337, -341 and -323 mV., respectively. While organic loading were 0.67, 0.83, 0.87, 0.95, 1.11, 1.20 and 1.78 kg.COD/m3-day, the grease & oil removal efficiencies were 68.3, 79.4, 84.6, 84.2, 78.8, 89.8 and 83.8%, respectively. In addition the study showed that the biogas was not produced due to inhibition from toxic compounds and poor biodegradability of some substrate compounds present in this wastewater. Additional experiments were conducted to study parameters that can inhibit the methanogenic activity, at organic loading 2.50 and 3.00 kg.COD/m3-day. Sulfate is expected to be the main cause of the problem. The experiment indicated that the sulfate concentration in the wastewater was presented at high concentration, more than 900 mg./l, so this was a cause of the biogas inhibition. The COD removal efficiencies were 57.23 and 51.53%, respectively. However, that data showed the COD removal efficiency was more that 80% at organic loading less than 1.0 kg.COD/m3-day and it would drop with increasing organic loading.
