Rivers are considered as one of the main resources of water supply for various applications such as agricultural, drinking and industrial purposes. Also, these resources are used as a place for discharge of sewages, industrial wastewater and agricultural drainage. Regarding the fact that each river has a certain capacity for acceptance of pollutants, nowadays qualitative and environmental investigations of these resources are proposed. In this study, qualitative investigation of the Talar river was done according to Oregon Water Quality Index (OWQI), National Sanitation Foundation Water Quality Index (NSFWQI) and Wilcox indicators during 2011-2012 years at upstream, midstream and downstream of the river in two periods of wet and dry seasons. According to the results of OWQI, all of the values at 3 stations and both periods are placed at very bad quality category and the water is not acceptable for drinking purposes. According to NSFWQI, the best condition was related to the upstream station at wet season period (58, medium quality) and the worst condition was related to the downstream in wet season period (46, very bad quality). Also the results of Wilcox showed that in both periods of wet season and dry season, the water quality is getting better from upstream station to the downstream station, and according to the index classifi cation, the downstream water quality has shown good quality and it is suitable for agriculture.
In many countries such as Iran, social and industrial developments changed the qualitative characteristics of the river's water quality and leads to excessive pollution. The first step for river water quality management is obtaining information on changes of river water quality in dimensions of time and place and also, determination of major sources of pollutants. WQI is a mathematical and statistical tool for conversion of quantitative values of large quantity of water quality data into single number which presents a simple and understandable tool for qualitative assessment. In current study, samples were collected from stations at up, middle and downstream of three rivers in Mazandaran province (Siahrod River, Haraz River and Babolrod River) in a 2 years interval of 2012-2013 years. The values of NSFWQI (water quality index of America's national health organization) were calculated for all stations and all of the stations were located on the level of unsuitable conditions. According to NSFWQI, the best condition was related to the upstream of Haraz River and the worst condition was related to the downstream of Siahrood River.
<p>Application of UASB method for wastewater treatment of canned fish factory reduces the costs of pre-treatments processes such as neutralization, and also reduced the costs of final aeration process. In this study, an UASB reactor which was equipped with a 3-phase separator system has been used. At first, a complex of anaerobic digester sludge and return sludge of activated sludge was added to reactor with ratio of 25 to 15. Then, the wastewater of factory entered into the reactor with inlet Organic Loading Rate (OLR) of 0.5 kg/m3.day which was increased gradually up to 4 kg/m3.day. Then, sampling was done for various tests during 75 days. The results of this study showed that UASB method neutralized and reduced the pH of the inlet wastewater from 10.5 to 7.3; and also reduced the SS of the inlet wastewater from 43 gr/l to 8 gr/l. the COD removal rate of this method was around 87%.</p><p>Keywords: canned fish wastewater, anaerobic treatment, UASB, COD, OLR.</p>
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.