Search results for "Water quality"
showing 10 items of 309 documents
Implementation of pressure reduction valves in a dynamic water distribution numerical model to control the inequality in water supply
2013
The analysis of water distribution networks has to take into account the variability of users' water demand and the variability of network boundary conditions. In complex systems, e.g. those characterized by the presence of local private tanks and intermittent distribution, this variability suggests the use of dynamic models that are able to evaluate the rapid variability of pressures and flows in the network. The dynamic behavior of the network also affects the performance of valves that are used for controlling the network. Pressure reduction valves (PRVs) are used for controlling pressure and reducing leakages. Highly variable demands can produce significant fluctuation of the PRV set po…
Spatial diversity of chlorine residual in a drinking water distribution system: application of an integrated fuzzy logic technique
2014
A reduction in the concentration of chlorine, which is used as a chemical disinfectant for water in drinking water distribution systems, can be considered to be an index of the progressive deterioration of water quality. In this work, attention is given to the spatial distribution of the residual chlorine in drinking water distribution systems. The criterion for grouping the water-quality parameters normally used is highly subjective and often based on data that are not correctly identified. In this paper, a cluster analysis based on fuzzy logic is applied. The advantage of the proposed procedure is that it allows a user to identify (in an automatic way and without any specific assumption) …
Mercury concentration, speciation and budget in volcanic aquifers: Italy and Guadeloupe (Lesser Antilles)
2009
Abstract Quantifying the contribution of volcanism to global mercury (Hg) emissions is important to understand the pathways and the mechanisms of Hg cycling through the Earth's geochemical reservoirs and to assess its environmental impacts. While previous studies have suggested that degassing volcanoes might contribute importantly to the atmospheric budget of mercury, little is known about the amount and behaviour of Hg in volcanic aquifers. Here we report on detailed investigations of both the content and the speciation of mercury in aquifers of active volcanoes in Italy and Guadeloupe Island (Lesser Antilles). In the studied groundwaters, total Hg (THg) concentrations range from 10 to 500…
Management of Arfak Rainbow Fish Based on Bioecologycal Aspect (Case in Some River in Manokwari)
2018
The aim of this research is to study the bioecological aspect of Arfak Rainbowfish, distribution long-wieght frequency and management of endemic arfak rainbow fish in Manokwari. This study conducted for five months from 7 September 2015 to 9 Januari 2016. Fish sample were collected from Prafi river, Nimbai river and Aimasi river and brought to fisheries laboratory. The method of this research is descriptive methode with field observation. The result of water quality parameters are temperature average 30.01oC±1,06oC, flow rate is slow 0.92±0,12, the pH 7,80±0,12, oxygen solute 5,38±0,24, average biological oxygen demand for Prafi river 4 mg/L, Nimbai river 3.1 mg/L, Aimasi river 5.2 mg/L and…
A hydrodynamic water quality model for propagation of pollutants in rivers.
2010
Numerical modelling can be a useful tool to assess a receiving water body's quality state. Indeed, the use of mathematical models in river water quality management has become a common practice to show the cause-effect relationship between emissions and water body quality and to design as well as assess the effectiveness of mitigation measures. In the present study, a hydrodynamic river water quality model is presented. The model consists of a quantity and a quality sub-model. The quantity sub-model is based on the Saint Venant equations. The solution of the Saint Venant equations is obtained by means of an explicit scheme based on space-time conservation. The method considers the unificatio…
Kondisi Fisika Kimia Air Sungai Yang Bermuara di Teluk Sawaibu Kabupaten Manokwari
2017
This research was conducted in three small rivers (Momo, Sahara and Konto), which empties into the Gulf Sawaibu Manokwari District. Water sampling for the third observation station made for the measurement of physical parameters such as temperature, TDS, TSS and turbidity, and chemical parameters pH, DO, COD, BOD, nitrate (NO3), phosphate (PO4) and Ammonia. The purpose of this study was to determine the physical quality of the river water chemistry research sites, and compared with water quality standards based on Government Regulation No. 82 of 2001 on water quality management and water pollution control. The results of measurements of physical and chemical parameters is the temperature ra…
Comparing modified biological monitoring working party score system and several biological indices based on macroinvertebrates for water-quality asse…
2005
Abstract Macroinvertebrate communities from the lower Nysa Klodzka River catchment, southern Poland, were analyzed seasonally, in order to assess changes in their composition and structure, in relation to water quality. Two major groups of sites, differing in both morphological structure and taxonomical composition by cluster analysis, were identified within the catchment area. Wider and deeper sites, located along the Nysa Klodzka River, were associated with the dominance of Chironomidae. Sites assigned along tributaries were characterized by a diversified structure of dominant taxa, including Oligochaeta, Hirudinea, Crustacea, Trichoptera, Ephemeroptera and Diptera. The performance of the…
Organic residues in lake and drinking water from the lagoa de Juturnaíba (região dos lagos - RJ, Brazil)
1997
Various analytical methods for the determination of organic residues in water were applied to samples from the Lagoa de Juturnaíba in the Região dos Lagos, east of Rio de Janeiro. The concentrations of more than 60 pesticides and of different aminopolycarboxylic acids were determined using GC/MS detection, and a GC/MS screening procedure was applied to detect additional compounds. None of the investigated pesticide residues could be detected in the lake water at detection limits of less than 100 ng/L. EDTA was detected at a concentration level of 2 mg/L in the lake and in drinking water prepared from this lake. Traces of biphenyl were identified by GC/MS in the lake water, the source of whi…
Three-Dimensional Calibration for Routine Analyses of Bromide and Nitrate Ions as Indicators of Groundwater Quality in Coastal Territories
2019
Nitrate and bromide ions are generally considered indicators of anthropogenic pollution and seawater intrusion, respectively, in the groundwater of coastal territories. The analysis of these species is generally carried out with routine chromatographic analyses which generally afford partially merged or poorly resolved peaks. In the present paper a simple method for the correct evaluation of their concentration in water is reported. This method does not imply utilization of other instruments or technologies, only the mathematical elaboration of the data obtained from routine analysis of standard solutions containing the two species. Standard binary solutions of nitrate and bromide ions at d…