tailieunhanh - Treatment of tannery wastewater by intermittent cycle extended aeration system

Treatment of tannery wastewater by intermittent cycle extended aeration system. A continuous-flow sequencing batch reactor known as the int ermittent cycle extended aeration system – sequencing batch reactor (ICEAS – SBR) was used to investigate the treatability of the tannery wastewater. | No 6(31) – 2016, Dec. 2016 Scientific Journal Of Thu Dau Mot University TREATMENT OF TANNERY WASTEWATER BY INTERMITTENT CYCLE EXTENDED AERATION SYSTEM Truong Trong Danh, Nguyen Dinh Tri, Nguyen Tan Phong Ho Chi Minh City University of Technology (VNU HCM) ABSTRACT A continuous-flow sequencing batch reactor known as the intermittent cycle extended aeration system – sequencing batch reactor (ICEAS – SBR) was used to investigate the treatability of the tannery wastewater. A model made from poly acrylic with a capacity of 20 liters was utilized to evaluate COD and nitrogen removal while the loading rate increased up to kg COD/. The polyvinyl alcohol (PVA) media was used to compare with the non-media condition. At the loading rate of kg COD/ with or without media, the removal efficiency was and COD, and TKN, and TN, respectively. It proved that PVA media helped increasing the removal efficiency. However, because of high concentration of the influent suspended solid and low C/N ratio input, the removal efficiency was not quite high. Keywords: ICEAS, PVA, tannery wastewater 1. INTRODUCTION Tannery wastewater is a source of many environmental impacts. Tannery productive cycle includes a series of chemical treatments using several different chemicals such as surfactants, acid and metal organic dyes, natural or synthesis tanning agents, sulphonated oils, salts, etc. [1]. Due to a wide range of chemicals and their low biodegradability, the biological treatment of tannery wastewater is difficult and complicated. It is stated that sequencing batch reactor (SBR) is an effective system for COD removal in tannery wastewater [2]. Moreover, a low effluent nitrate concentration could be obtained in suitable COD/TKN ratio condition [3]. A modification of the SBR process is the intermittent cycle extended aeration system – sequencing batch reactor (ICEAS – SBR), which is operated on the principle of continuous influent as