Volume 2 • Issue 1 • 1000111 Hydrol Current Res ISSN: 2157-7587 HYCR, an open access journal Open Access Research Article Tripathi and Tripathi Hydrol Current Res 2011, 2:1 DOI: 10.4172/2157-7587.1000111 Removal of Organic Content and Color from Secondary Treated Wastewater in Reference with Toxic Potential of Ozone During Ozonation Smriti Tripathi 1 , Devendra Mani Tripathi 2 and B D Tripathi 1 * 1 Centre for Environmental Science & Technology, Banaras Hindu University, Varanasi, 221005, India 2 Pollution Ecology Research Laboratory, CAS Botany, Banaras Hindu University, Varanasi-221005, India *Corresponding author: B D Tripathi, Centre for Environmental Science & Technology, Banaras Hindu University, Varanasi, U.P, 221005, India, E-mail: smrititripathibhu@gmail.com Received November 28, 2010; Accepted March 01, 2011; Published April 22, 2011 Citation: Tripathi S, Tripathi DM, Tripathi BD (2011) Removal of Organic Content and Color from Secondary Treated Wastewater in Reference with Toxic Potential of Ozone During Ozonation. Hydrol Current Res 2:111. doi:10.4172/2157- 7587.1000111 Copyright: © 2011 Tripathi S, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract Present study was conducted to evaluate the impact of ozonation on the quality improvement of Secondary Treated wastewater at Varanasi, in India. Physico- chemical parameters such as BOD, COD, TOC, UV 254 , color and microbiological parameters such as E. coli, fecal coli. & total coliform disinfection parameters were used to evaluate the effciency of ozone to upgrade secondary effuent quality. Experimental results revealed that 10 mgL -1 O 3 for 5 minutes exposure duration was found most suitable dose and contact time for the signifcant reduction of physico- chemical parameters of secondary treated wastewater such as BOD, COD, TOC, UV 254 and color i.e. 30%, 14.3% 45% & 60% respectively as well as it enhanced the biodegradability more than 50% in the treated water. Our data also revealed that this applied dose and exposure time is responsible for the highest degradation of microbiological parameters i.e. >98%. Other than this the toxic response of test species was infuenced mainly by the dose and exposure time. The acute toxic effect after ozonation was observed on V. fscheri and found that toxic effect of the secondary effuent was decreased after applied dose and exposure duration. Results supported the expectation that the process of Ozone might enhance the overall treatment effciency of secondary effuent treatment. Keywords: Ozonation; Biodegradable organic carbon; Secondary treated wastewater; Physico-chemical Properties; Toxicity Introduction Water is considered to be the most import pillar of modern civilization in all aspect of life so the presence of harmful organic compounds and pathogenic microorganisms in the water increases the magnitude of water pollution on human health and livelihoods [1-4]. Te increasing pressures of wastewater discharge on water supplies and the shortage of water resources, more and more attentions have been paid on the proper treatment of wastewater [5-7]. Te conventional and advanced treatment processes (i.e. microfltration (MF) or ultra-fltration (UF) technology) are well- known but due to large land occupation, complicated operation, sophisticated management and its higher cost cannot be widely used [7-9]. Growing concerns about the environment have resulted in the development of new environment friendly higher treatment efciency and cost efective technologies, to minimize the problem of wastewater [7,10,11]. Now a day ozone is used worldwide and has been largely applied in the treatment of wastewater [12]. Ozone, a highly oxidative agent, react directly or via a hydroxyl radical mechanism results into the reduction of organic content with increase of biodegrability of natural organic matter and the efcient inactivation of a wide range of microorganisms [6,13-15]. Ozonation has been used to meet discharge requirements for coliform and virus inactivation since the 1970s [16]. Frequent Ozonation for treatment of wastewater and drinking water is due to its ability to oxidize complex organic molecules, phenols, Endocrine Disruptive Chemicals (EDCs) and pharmaceuticals [17-21]. In combination of microbial disinfection make ozonation an attractive alternative for advanced wastewater treatment [22]. Earlier, corona discharge was the main source for the generation of Ozone, which requires much higher resource and economy for the treatment of water with ozone. So, it was limited to certain areas viz UV lights for the drinking water treatment. Due to aforesaid reasons it was not only feasible for treatment of municipal sewage. Recent ozone generation techniques viz UV lights require lower energy consequently; costs are also reduced making the feld application of Ozonation economically viable [23,24]. In order to estimate the overall environmental impact of ozonated wastewaters, several studies have been conducted incorporating bioassays along with physicochemical and microbiological determinations [25]. Ecotoxicological testing provides an overall direct estimation of the environmental hazard of efuents, by the exposure of selected test species on the respective samples and the determination of certain end-points, such as lethal efect, growth ability, etc. Terefore, bioassays consist of an attractive and promising alternative and can be performed supplementary to chemical determinations for the assessment of the environmental impact of efuents the corresponding results were variable and depended on both the nature of the test and the aquatic sample characteristics [26-28] indicated that the toxic responses of ozonated secondary efuents on the survival and reproduction of Ceriodaphnia dubia were site-specifc and presented seasonal variation (ozonation conditions: 1-3 mgL -1 ozone dose for 10 min., followed by 5 min. of residual ozone exposure). Similar results have been reported by Monarca et al. [20], who studied the efect of ozonated secondary efuents (at specifc optimized ozonation conditions concerning certain microbiological parameters) on bacteria Vibrio fscheri. Nakamuro et al. [21], Ono et al. [22] and Takanashi et Hydrology Current Research H y d r o l o g y : C u r r e n t R e s e a r c h ISSN: 2157-7587