توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱investigation on effects of waste from crude oil storage tanks on chemical features of the soil
نویسنده(ها): ، ،
اطلاعات انتشار: اولین همایش بین المللی بحران های زیست محیطی ایران و راهکارهای بهبود آن، سال
تعداد صفحات: ۷
arrival oil pollution , chemical features of soil influence and change. According to several oil fields in Iran, including mining centers (offshore drilling), desalination facilities, transfer stations and oil refineries , Whereas Cleanup of petroleum contaminated soils is a complex and costly process , so achievement to model the effects of oil pollution and waste resulting from them, Appropriate options for managing wastewater discharges, oil can prevent infection presented. So far, studies on the variation of soil parameters and the impact of waste oil and crude oil are taken. In this research , effects of waste from crude oil storage tanks on pH , TDS , OC and TPHs , in seven stations including four polluted stations , two semi polluted stations and one control area in two period of sampling (March and June) , was tested. The results indicate that significant changes in these parameters because of waste oil.TDS in polluted samples was 480% increased because of the high amount of TDS in wastewater tanks and EC is also looking up. Organic carbon is also 740% increased. It is affected from the organic compounds presented in crude oil. TPHs have a very large increase because of existence oil hydrocarbons in effluent. The overall results show the impact of wastewater on soil chemical features.<\div>

۲Survey of Chitosan with Polyaluminum Chloride in turbidity removal from Ahwaz water treatment plant
نویسنده(ها): ، ،
اطلاعات انتشار: اولین همایش بین المللی بحران های زیست محیطی ایران و راهکارهای بهبود آن، سال
تعداد صفحات: ۷
The water that has been contaminated by human or naturally for changing into drinkable water it should go through different process of refinement. The current water treatment process include: screening, coagulation, making the clot treatment, sedimentary, water treatment and disinfection. Coagulation is a process that in the course of it the little non_settling particles that called colloidal and are an important factor in appearing the turbidity sticking together and format the bigger particles which can be settle. The process of water treatment without the use of materials which increase the precipitation of intensely particles seems to be impossible[1].In the process of coagulation, we use different coagulant and coagulant aids materials. The coagulant materials include the materials which are used for unstabling the particles and sticking them together. while using of coagulant aids materials is a help for faster sedimentary and increase the density of Adherent particles [2].Aluminum salts and iron are the most are the most current coagulants which are used for water treatment and waste water. But in recent years a new kind materials called inorganic polymeric flocculants (IPFS)1 are provided with the use of ordinary iron salts and aluminum. Poly aluminum chloride(PAC) is one of the most important kinds of (IPFS) that is more useful than the other kinds [3,4].Serious detriments had been obtained because of using aluminum salts and remaining it in the water and producing a big quantity of sludge and they way of disposal it in the environment[5].According to Mack Dermot (1987) and his colleagues survey, there is a meaningful connection between increasing the aluminum law, average and high turbidities are 10 and 1mg\l and the maximum turbidity elimination for 73.4 percent is 5 and 0.5 mg\l and the maximum turbidity elimination for96 percent is 5 and 0.5 mg\l and the maximum turbidity elimination for 98.2 percent had been obtained[13]. Bing–tao and his colleagues at 2008 worked onstudying the effect and the mechanism of chitosans coagulant aids to eliminate the turbidity of organic materials in the drinkable water. The poly aluminum chlorides optimum concentration had been obtained at 35mg\l and for chitosan 0.15mg\l and 7.5 optimumpH[14].Wang and his colleagues at 2009, worked on studying the effect of chitosan as a coagulant aids on the Floces shape and firmness. According to optimum condition to eliminate the turbidity, chloride ferrics optimum doses had been obtained at 29mg\l and0.1mg\l for chitosan. The formed Floces by chitosan were bigger and had a high precipitation and caused the floces not to be broken easily [15]. Roussy and hiscolleagues at 2005, worked on studying the effect of concentration of brain tissues in the seven sick people who are suffering from encephalopathy dialysis with the concentration of this element in the dialysis liquid[6].For minimizing each kind of potential riskarising from the aluminum remaining in the watertreatment that in it flocculants aluminum has been used, water treatment process should be optimized forreducing the rate of remaining aluminum to the lowest possible level. with the purpose of solving the problems related to chemical flocculants, a lot of researches hasbeen done in the recent years about natural flocculants that in this respect we can mention chitosans application[7].Chitosan<\div>

۳Efficiency Evaluation of Powdered Activated Carbon as Coagulant aid in Ahvaz Water Treatment Plant
نویسنده(ها): ،
اطلاعات انتشار: اولین همایش بین المللی بحران های زیست محیطی ایران و راهکارهای بهبود آن، سال
تعداد صفحات: ۵
In recent decades, increasing pollution of water resources has caused higher rates of organic pollutants in water resources. Considering the surface water resources as one of the main water supplies in many regions of Iran and the application of chlorination for disinfecting drinking water has increased the rate of disinfection By–Products (DBPs) formation. Trihalomethanes (THMs) as the main group of DBPs are categorized and considered to have the potentiality of increasing the rate of liver, kidney and CNS adverse effects.This study which presents experimental results, aimed at the reduction of organic matters by the use of powdered activated carbon (PAC) in the process of coagulation in Koot Amir water treatment plant in Ahwaz city, the affection of two coagulant such as Ferric chloride and Poly aluminum chloride (PACl) with PAC in removing Total Organic Carbon (TOC) considering different elements such as concentration and the kind of coagulants, concentration of PAC, pH changes and contact time has been surveyed. The results of this study clearly indicated that maximum removal in optimum pH of Ferric Chloride has been 40% while 44 percent TOC removal has been achieved at pH 6.5 for Poly Aluminum Chloride coagulant. In use of powdered activated carbon with optimum pH and concentration of Ferric Chloride, TOC reduction will increase with increasing PAC concentration and will be 90 percent. Also the increase of powdered activated carbon in similar conditions along with Poly Aluminum Chloride 87 percent reduction has been occurred.<\div>

۴Survey of Poly Aluminum Chloride as CoagulantForOrganicmatter, Turbidity and MicroorganismsremovalFrom Karoon River in Iran
نویسنده(ها): ، ،
اطلاعات انتشار: کنفرانس بین المللی علوم، مهندسی و فناوری های محیط زیست، سال
تعداد صفحات: ۱۲
PAC hydrolyses with great ease as compared to alum, emitting polyhydroxides with long molecularchains & greater electrical charge in the solution, thus contributing to maximize the physical action of theflocculation. Better coagulation is obtainedwith PAC as compared to alum at medium & high turbidity waters.Floc formation with PAC is quite rapid. The sludge produced by PAC is more compact than that produced byalum.The study was carried out at Water Treatment Plant. in order to determine the optimum conditions of PAC performance in turbidity, coliform bacteria and heterotrophic bacteria removal, tests were performed based on variables such as coagulant dose (3,5,8,10,15,20,30,40,50 mg\Lit), pH(5.5, 6, 6.5, 7, 7.5, 8) and turbidity between 33–100 NTU. The residual turbidity and microbial parameters of samples were measured and coagulant performance in turbidity and microbial parameter removal were determined. The results showed that the most optimal conditions for turbidity removal and microbial parameters efficiency by PAC were pH=8, flash mixing =120 rpm and the optimal doses of PAC were obtained as 10 and 30 ppm. The turbidity, total coliform, fecal coliform and Heterotrophic bacteria removal efficiency under optimum condition of PAC application for dose 10ppm were, respectively, 96.59, 90, 82.75, 84.17% while turbidity, total coliform, fecal coliform and heterotrophic bacteria removal efficiency under optimum condition of PAC dose of 30ppm was 99 , 94.65 , 88.94 , 90.47%, respectively.<\div>

۵Chitosan from Shrimp as a Natural and Low cost Coagulant Aid for fine suspended and Colluidal solids in Karoon River
اطلاعات انتشار: کنفرانس بین المللی علوم، مهندسی و فناوری های محیط زیست، سال
تعداد صفحات: ۱۳
Chitosan, a natural biopolymer,biodegradable, nontoxic, high molecular weight, linear cationic polymerwas evaluated for its ability to be used as a coagulant to treat water for potable use.Chitosan is a biodegradable cationic polymer derived by de–acetylation of chitin. This study aims to investigate the effect of chitosan as a coagulantaidsfor improvement of poly aluminum chloride coagulant in removing the turbiditiesfrom drinkingwater.This study conducted in the laboratory using jar test device in water treatment of Ahvaz.Chitosan was tested as a natural coagulant in the removal of the turbidity of Karoon water to replace inorganic coagulants ( PAC) having hazardous effects. Jar test was performed to test some factors that may affect the coagulation process. The factors tested were dose of coagulant (0–22mg\L), initial pH (5–9), type of oagulant chitosan versus PACcoagulants), and thechitosan solvent.Optimal pH for removing the turbiditieswas observed in pH=8. Optimal dosage of poly aluminum chloride together with chitosan was obtained 5 mg\L and 0.02 mg\L respectively. Under optimal conditions, using chitosan could reduce about 50% of concentration of polyaluminum chloride coagulant.WhenPAC concentration was 10mg\L, by adding 0.02mg\L of chitosan to the process, maximum turbidity removal was %99.16.Results indicate good performance of chitosan as a coagulantaidsfor removing the turbidities from drinkingwater.<\div>

۶Efficiency of the chitosan as natural coagulant with PAC in removing turbidity from Municipal water treatment plant (case study: Ahvaz water treatment plant)
نویسنده(ها): ، ،
اطلاعات انتشار: کنگره بین المللی پایداری در معماری و شهرسازی معاصر خاورمیانه، سال
تعداد صفحات: ۱۸
Karun River is the largest and most watery river in Iran. This river is the longest river which located just inside Iran and Ahvaz Metropolis drinking water supplied from Karun River as well . Karun River as the main source of water treatment plants in Ahvaz, like most surface waters affected by various contaminants which caused changes in water quality of the river .Chitosan is a biodegradable cationic polymer derived from the deacetylation of chitin. This study aims to investigate the effects of chitosan as a coagulant aid for the improvement of a polyaluminum chloride coagulant in removing the turbidity from drinking water. This study was conducted in the laboratory using a jar test in the water treatment plant of Ahvaz, Iran. Experiments were conducted based on various variables such as concentration of coagulant, pH, and different concentrations of chitosan as a coagulant aid. After preparation in a jar test, samples were mixed fast at 120 rpm for 1 min and slowly at 30 rpm for 15 min and remained under stable conditions for 30 min to allow for settlement. The optimal pH for the removal of the turbidity was pH 8. The optimal dosage of polyaluminum chloride combined with chitosan was 5 and 0.02 mg\L, respectively. Under optimal conditions, the use of chitosan could reduce the concentration of polyaluminum chloride by approximately 50%. The investigation showed that the optimal concentration of PAC for turbidity removal was 10 mg\L. When the PAC concentration was adjusted to 10mg\L, adding 0.02mg\L of chitosan to the process, maximum turbidity removal was achieved at 99.16%. In addition, particles formed in flocculation by chitosan were coarser and settled faster. Results indicated good performance of chitosan as a coagulant aid for the removal of the turbidity from drinking water.<\div>

۷Evaluating the Efficiency of Tragacanth Coagulant Aid in Removing Colloidal Materials and Suspended Solids Creating Turbidity in the Water of Karun River
اطلاعات انتشار: Journal of Environmental Health and Sustainable Development، اول،شماره۱، Spring ۲۰۱۶، سال
تعداد صفحات: ۱۰
Introduction: Colloidal materials and suspended solids cause turbidity in water. To remove turbidity, clarification method is used that includes processes of coagulation, flocculation, and sedimentation. Due to the long duration of coagulation process, coagulant aids are applied. Despite the favorable efficiency of synthetic polyelectrolytes as a coagulant aid, due to their harmful effects on human health, in this process natural organic polymers are used instead.Methods: In this research, the use of tragacanth as a natural organic coagulant aid instead of synthetic polymers in water turbidity removal along with alum and poly aluminum chloride is studied. To compare the experiments with natural conditions, Karun River water is analyzed. To complete these studies, the effects of several factors such as tragacanth concentration, the concentration of alum and poly aluminum chloride, and pH changes in average and low turbidity are investigated. Optimum pH for turbidity removal was determined by jar testing.Results: The results showed that the best pH to remove turbidity is 5.5 to 7, with the efficiency of 97.3%. At PH = 6 and at the concentration of 30 mg\L, poly ammonium chloride has maximum efficiency (90%). Using tragacanthat concentrations of 1 and 4 mg\L along with alum at a concentration of 40 mg\L leads to turbidity removal of 81.75%.Conclusion: Using 2 and 4 mg\L of tragacanth, a significant removal efficiency is achieved in low and average turbidity.pH=7 leads to the most efficient use of tragacanth coagulant aid.

۸Investigation of the Excess Sludge Reduction in SBR by Oxidizing Some Sludge by Ozone
اطلاعات انتشار: Iranian Journal of Chemistry and Chemical Engineering (IJCCE)، بيست و هشتم،شماره۴(پياپي ۵۲)، ۲۰۰۹، سال
تعداد صفحات: ۱۰
The excessive biological sludge production is one of the disadvantages of aerobic process such as SBR. So the problem of excess sludge production along with its treatment ، and disposal in aerobic processes in municipal and industrial waste water can be seen in many parts of the world even in our country . to solve the problem of excess sludge production ، reducing in by oxidizing some of the sludge by Ozone is a suitable idea ، thus reducing the biomass coefficient as well as the sewage sludge disposal. In this study، Two SBR reactors with of 20 liter being controlled by on–line system are used. After providing the steady state in the reactors، along the 8 month research sampling and testing parameters such as COD، MLSS، MLVSS، DO، SOUR، SVI، residual ozone and Yield coefficient were done. The results showed that during the solid retention time of 10 days the kinetic coefficient of Y and Kd was 0.58 (mg Biomass \ mg COD) and 0.058 (1\day) respectively. At the next stage of research، different concentrations of ozone in one liter of the returned sludge to reactor were used to reduced the excess biological sludge production. The results showed that the 20 mg ozone per gram of MLSS in one liter of the returned sludge to reactor is able to reduce Yield coefficient from 0.58 to 0. 28 (mg Biomass\mg COD)، In other words، the biological excess sludge by 52 % .but the soluble COD increased slightly in the effluent and the removal percentage decreased from 92 in blank reactor to 64 in test reactor. While the amount of SVI and SOUR in this consumed ozone concentration reduced 9 mgO2\h.gVSS and 20 ml\g respectively. No sludge was seen in the 25 mg ozone concentration per gram of MLSS in one liter of the returned sludge to reactor.
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