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Search Results: 1 - 10 of 18136 matches for " water clarification "
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Use of extract of moringa seeds as coagulant agent in treatment of water supply and wastewater
Paola Alfonsa Vieira Lo Monaco,Antonio Teixeira de Matos,Ivan Célio Andrade Ribeiro,Felipe da Silva Nascimento
Ambiente e água : An Interdisciplinary Journal of Applied Science , 2010,
Abstract: The objective of this work was to evaluate the efficiency of the extract of moringa (Moringa oleifera) seeds when used as a coagulant agent, in removal of turbidity and coliform in domestic sewage, pig wastewater and water to be used for public supply. To evaluate the effect of coagulant on each type of water, tests were performed using the Jar-test apparatus, and was evaluated the effects of the concentrations of 0.02; 0.04; 0.06; 0.1; 0.2; 0.3; 0.4; 0.6; 0.8 and 1.2 g of powdered seeds per liter of analyzed water. Turbidity was measured in suspensions after 2 and 24 h and counting of organisms of the group total coliforms (TC) and fecal or thermotolerants coliforms (FC) after 24 h of application and mixing of the coagulant. Mathematical equations were fitted by regression, relating the concentration of the extract of moringa seeds in water samples with turbidity. It was found that in the water to be used for public supply, the concentration of 0.4 g L-1 of moringa seeds to a sedimentation time of 2 h presented the best turbidity removal (98%). In equal sedimentation time, the average removal of turbidity in the domestic wastewater was 22.3%. On a larger sedimentation time (24 h), the average removal is increased to 35.3%. The addition of extract of moringa seeds not presented turbidity removal of pig wastewater. With regard to the removal of TC and FC, the concentration of 0.2 g L-1 of seeds was the most suitable for water to be used for public supply, obtained 90% of FC removal. In the case of domestic sewage, the best concentration was 0.04 g L-1 of seeds, has been obtained removals of 95.6 and 94.3%, respectively, and in pig wastewater, the best concentration was 0.8 g L-1 of seeds, which presented removals of 96.5 and 94.8%, respectively.
Investigation of coagulation activity of natural coagulants from seeds of different leguminose species
??iban Marina B.,Kla?nja Mile T.,Stojimirovi? Jelena Lj.
Acta Periodica Technologica , 2005, DOI: 10.2298/apt0536081s
Abstract: The ability of seeds of plants: Phaseolus vulgaris, Robinia pseudoacacia Ceratonia siliqua and Amorpha fruticosa, to act as natural coagulants was tested using synthetic turbid water. This water was prepared by adding kaolin into tap water, just before the test. Active components were extracted from ground seeds with distilled water. The coagulation ability of this extract was assessed by the use of standard jar test measurements in water with various initial turbidity. Investigation of these natural coagulants was confirmed their positive coagulation activity. Of all plants that have been examined, the seed extract from Ceratonia siliqua appeared to be one of the most effective coagulants for water treatment. A dose of 20 mg/l of this coagulant resulted in 100% coagulation activity for clarification of water with 17.5 NTU initial turbidity.
The investigation of coagulation activity of natural coagulants extracted from different strains of common bean
??iban Marina B.,Vasi? Mirjana A.,Prodanovi? Jelena M.,Antov Mirjana G.
Acta Periodica Technologica , 2010, DOI: 10.2298/apt1041141s
Abstract: Coagulation and flocculation by adding chemicals are the methods that are usually used for removal of water turbidity. This study is concerned with the coagulation activity of extracts of various strains of bean. The aim was to ascertain if bean varieties influence coagulation activity. Active components were extracted from 1 g of ground sample with 100 ml distilled water. Contents of dry matter and nitrogen were specified in the solid samples, and the content of soluble nitrogen was determined in the extracts. These data were used to calculate the efficiency of extraction of nitrogen-containing compounds. The coagulation activity was assessed by jar test using synthetic turbid water, of the initial pH 9 and turbidity 35 NTU. The jar test was carried out by adding different amounts of extracts to model water, and stirring the content. After sedimentation for 1 h, residual turbidity was determined by turbidimeter and coagulation activity was calculated. The increment of organic matter concentration after the coagulation was also determined. These experiments confirmed that extracts of all investigated strains of bean could be used successfully as natural coagulants.
Ilker Erdem, Mehmet Baltac?o?lu, Muhammet Bilgi
Journal of the Turkish Chemical Society, Section B: Chemical Engineering , 2016, DOI: -
Abstract: Photocatalytic oxidation is a preferable method for clarification of fresh water polluted by colourful pollutants, pesticide-like hard to treat organic pollutants and microbiological metabolites. Titanium dioxide (TiO2), having superior physicochemical properties, is one of the most common catalyst in heterogeneous photocatalysis. Free electron formed by absorption of light by titanium dioxide triggers formation of free radicals and results in oxidation of polluting compounds. Titanium dioxide is photocatalytically more active under the relatively shorter (100 nm < λ < 400 nm) UV wavelength region. This forces the usage of UV lamps for supplying UV light, which is only present at low ratios in the sunlight (8%). Doping with various elements, preparing of its composites with different oxides, usage of dyes absorbing sunlight were investigated for enhancing the photocatalytical activity of titanium dioxide and using the sunlight as energy source and some enhancements were reported. Using titanium dioxide in nano size was also reported to be enhancing its photocatalytical activity. In this work, while organic wastes rich in Carbon were milled to increase their surface area, nano sized titanium dioxide was synthesized via sol-gel method. Using these two materials C element and titanium dioxide in couple possible enhancement of the photoctatlytical activity of the synthesized material was investigated. Walnut shells were used as organic waste.
Recircula??o de água de lavagem de filtros e perigos associados a protozoários
Freitas, Adiéliton Galv?o de;Bastos, Rafael Kopschitz Xavier;Bevilacqua, Paula Dias;Pádua, Valter Lúcio;Pimenta, Jo?o Francisco de Paula;Andrade, Rosane Cristina de;
Engenharia Sanitaria e Ambiental , 2010, DOI: 10.1590/S1413-41522010000100005
Abstract: this paper presents the results of (i) the characterization of the filter backwash water (fbw) of vi?osa university water treatment plant; (ii) trials of fbw clarification in sedimentation columns, with and without polymer application; (iii) trials of fbw recycling in a pilot plant, under variable conditions of recycling flow rates (5 to 20% of the raw water flow - rw) and of the influent water (rw + fbw) turbidity (12.1 to 257.3 ut). around 101 giardia spp. cysts and cryptosporidium spp. oocysts per liter were found in the fbw. the results of sedimentation columns and recycling trials demonstrated that fbw clarification using polymers contributes to minimize hazards related to the introduction of giardia cysts and cryptosporidium oocysts.
Estudio Comparativo de Sulfato de Aluminio y Semillas de Moringa oleifera para la Depuración de Aguas con Baja Turbiedad
Lédo,Patrícia G.S; Lima,Raquel F.S; Paulo,Jo?o B.A; Duarte,Marco A.C;
Información tecnológica , 2009, DOI: 10.4067/S0718-07642009000500002
Abstract: the objective of the present work is to investigate the efficiency of a coagulant prepared from moringa oleifera seeds, for clarifying water samples with low turbidity from the jiqui lake, in the state of rio grande do norte, natal-brazil. the dosages and ph of the coagulants were changed within defined limits. jar-test essays and measurements of electrophoretic mobility were done to determine the zeta potential and the possible mechanisms involved in the coagulation process. the mechanisms of coagulation with moringa oleifera are absorption and neutralization of charges and absorption and bridging. the results suggest that for low turbidity waters, moringa oleifera seeds represent a potentially viable substitute of aluminum sulfate for water clarification.
DYNA , 2011,
Abstract: a study of water clarification process in industrial water treatment system using a polymerized inorganic coagulant (aluminum hydroxychloride) is made in this paper. initially, the most important conceptual elements of the stages of clarification process (coagulation, flocculation and sedimentation) are established. then, it identifies the major conventional coagulants used in water treatment and the polyaluminum chlorides (pac's) are mentioned as part of a new generation of alternative coagulants whose use has increased in recent decades because of their better performance with respect to conventional coagulants; technical and operational aspects to be considered when implementing a water clarification process using a pac as coagulant are specified. finally, some comparative data of water clarification process real operating conditions, from a previous work, which replaced a conventional coagulant (aluminum sulfate) by aluminum hydroxychloride are presented and a better performance of the process after the replacement is proved
Wash water in waterworks: contaminants and process options for reclamation

C B Chidambara Raj,Tan Ee Kwong,Wong Wai Cheng,Lee Mun Fong,Soh Hoo Tiong,Paul Stefan Klose,

环境科学学报(英文版) , 2008,
Abstract: Reclamation of clean water from filter backwash water was studied through pilot-scale experiments.The pilot plant consisted of clarification,sand-filtration,and ultrafiltration modules in sequence,with a provision to bypass the sand filter.Clean water that conformed to World Health Organization (WHO) guidelines on Potable Quality was reclaimed.Turbidity,aluminum and iron were found to be critical contaminants in process selection and design.Clarification,followed by sand filtration,was found to be the minim...
Influence of the composition of common bean extracts on their coagulation ability
Kuki? Dragana V.,??iban Marina B.,Tepi? Aleksandra N.,Prodanovi? Jelena M.
Acta Periodica Technologica , 2011, DOI: 10.2298/apt1142071k
Abstract: Coagulation and flocculation are the most used methods for removal of turbidity of water. Recently, many studies have focused on the investigation of natural coagulants for this purpose. In view of the fact that extracts of common bean have coagulation activity, this study is concerned with the chemical composition of these extracts and their influence on the coagulation activity. Extraction was conducted with distilled water, 0.5M NaCl and 1M NaCl and total sugars content, proteins, phytic acid and total phenolics content and their coagulation activity were determined in the obtained extracts. These experiments confirmed that an extraction time of 10 minutes is sufficient for the extraction of active coagulant components from common bean seeds and that water is satisfactorily efficient and most economical solvent.
Extraction and partial purification of coagulation active components from common bean seed
??iban Marina B.,Antov Mirjana G.,Kla?nja Mile T.
Acta Periodica Technologica , 2006, DOI: 10.2298/apt0637037s
Abstract: An active coagulation component was extracted from common bean seed by NaCl solution and the obtained crude extract was partially purified through a sequence of steps that included precipitation of protein by ammonium sulphate, desalting by dialysis and anion exchange. A turbid water was treated by protein fractions obtained in the anion- exchange elution process by stepwise increase in NaCl concentration. The jar tests were conducted at various dosages of eluates. Different mode of relation between coagulation activity and applied coagulant dose for each protein fraction indicated the existence of different mechanisms of coagulation/flocculation, depending of characteristics of different proteins in the fractions.
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