Search published articles


Showing 153 results for Waste

A. A Pourbabaee, F Karami, A Amirkhani, B Rajabpour,
Volume 3, Issue 2 (7-2010)
Abstract

Backgrounds and Objectives: True cholera with typical clinical features nearly always occurs by serologic groups O1 and O139 but the non-O1 group can produce a disease with same clinical characteristic sporadically. According to the important of climate and environmental conditions in the distribution and abundance of Vibrio cholera, in this study, the distribution of the serologic group was evaluated in different parts of Qom city with relation to the affected patients.
Materials and Methods: In this study 5220 environmental specimens were taken from 12 parts of Qom city and during different seasons of the year 1325, 60 clinical specimens were taken from the patients and all were evaluated for Vibrio cholera with standard methods. The study was of Descriptive and cross sectional and the results were analyzed with statistical soft ware (Epi-info).
Results: The most abundance of Nag strains were related to Emamzadeh Ebrahim and Sheikhabad parts and Shahed Street from Khak faraj and Niroogah area and the least abundance were related to Salariyeh area. The abundance distribution of Nag strain, 7 different specimens was most in hogwash, sewerage and vegetables and least in pipe water which reveal a significant difference (P< 0.05) according to statistical goodness of fit test. The frequency distribution of the patients in each part of area 4 with relevance to sex revealed that the most contamination percentage was attributed to Emamzadeh Ebrahim and Sheikhabad and Shahed from Niroogah area and no positive specimen was taken from Haftado-do-tan and Shahrdary areas.
Conclusion: According to high occurrence of the disease in same areas, and results from other researchers based on increased frequency of non-O1 strains in the environment during the epidemic, so can release a connection between Vibrio cholera O1 strains and non-O1 strains to conclude. On the other hand, none of the clinical and environmental samples, Vibrio cholera O1 was isolated, so probably human carriers in Qom, not the main factor is the emergence of this disease.


M Ahmadimoghadam, H Amiri,
Volume 3, Issue 2 (7-2010)
Abstract

Backgrounds and Objectives: Formaldehyde and phenol are key precursors in the industrial manufacture of resins. Toxicity of these compounds prevents function of microbial populations, so they affect the biological treatments. The aim of this study was investigation of TOC removal from phenol-formaldehyde resin manufacturing wastewater by electrocoagulation using Al- electrodes.
Materials and Methods: This study is the laboratory scale experiment was conducted as a pilot. Wastewater sample was adjusted in the desired pH, electrical conductivity and current density, then it was placed in to the reactor contains four electrodes in aluminum. The electrodes were connected to a DC power supply (0-40V, 0-3A). Samples were collected for TOC determination in the middle of cell at regular time intervals. Collected samples were analyzed using TOC analyzer.
Results:The results indicated that the optimum conditions for the removal of TOC were current density 75 A/m2, solution pH 4 and Conductivity 3 mS/cm. In this condition energy consumption was found 22.5 kWh m-3 after 60 min reaction.
Conclusion: This study shows that electrocoagulation of wastewater from phenol-formaldehyde resin manufacturing can be used as a pretreatment process.


A.r. Talaie Khozani, N Jafarzadeh Haghighi Fard, M.r Talaie Khozani, M. Beheshti,
Volume 3, Issue 2 (7-2010)
Abstract

Backgrounds and Objectives: Oil pollution can be generated as a result of spillage, leakage, discharge, exploration, production, refining, transport and storage of crude oil and fuels in the environment. Consequently, many researchers have developed and studied the chemical, physical and biological methods to degrade crude oil. Among them, the biological treatments are the most interesting as they are simple and economical methods. The aim of this study was to determine biokinetic coefficients of crude oil degradation by pseudomonas aerogenusa. This microorganism was isolated in our previous work.
Materials and Methods: In this study the bio-kinetic coefficients of crude oil biodegradation were evaluated. Pseudomonas aerogenusa bacteria which had been isolated from the soil sample taken from a gas station in our previous work were used in this study. This microorganism was cultured in the liquid medium containing crude oil as sole carbon source. Finally with determining the amount of microorganisms and crude oil concentration during biodegradation process, the bio-kinetic coefficients based on modified Monod equation were calculated.
Results: bio-kinetic coefficients obtained from laboratory studies are vital factors in industrial applications. As a result, the bio-kinetic study was performed to find bio-kinetic coefficients for biodegradation of crude oil using the isolated bacteria. The results showed that ,Y, k and were equal 0.107 , 0.882 , 9.39 and 169.3 respectively.
Coculusion:Our results showed that pseudomonas aerogenusa is usable for treatment of oily wastewaters in the full scale facility. Results of this study indicated bio kinetics confections.


H Banejad, V Yazdani, A.r Rahmani, S Mohajeri, E Olyaie,
Volume 3, Issue 3 (10-2010)
Abstract

Backgrounds and Objective: In arid and semi-arid regions of the world, urban runoff as a source of water restoration and is considered valuable. Wastewater treatment, while preserving the environment, it can be considered as water source. The aim of this study to evaluate the possibility of using powder grain Peregrina in wastewater treatment in comparing with Alum and PloyAluminum Chloride (PAC).
Materials and Methods: Flocculation and coagulation tests were done by Jar test. Wastewater quality parameters were measured according to standard method.
Results: Studies have been showed that in optimum Peregrina concentration, efficiency of turbidity reduction, total hardness, calcium hardness, magnesium hardness, total E. Coli are 95.11, 38, 55.5, 46.6, 97 and 97 percent respectively. It is noted that turbidity reducing directly related with coli form reduction. As, with increasing turbidity reduction, coliform reduction is increased. The most reduction of E. coli with combination of Alum, Ploy Aluminum Chloride and Peregrina was 100 percent. In optimum concentration of Alum, Ploy Aluminum Chloride and Peregrina, the quality of treated wastewater would be in the range of environmental standards. Therefore, treated wastewater can be entering to surface water and reuse as irrigation water.
Conclusion: The results derived from this study showed that the treated wastewater can be use in a variety of irrigation except sprinkler irrigation due to burn the leaves of plants. (high electrical conductivity).Also, the low cost of seed Peregrina and good performance in the refining operations, it is suggested that Peregrina as a replacement for poly aluminum chloride and an alum to be used for wastewater treatment.


M Meschi Nezami, H Ganjidoust, N Mokhtarani, B Ayati,
Volume 3, Issue 4 (1-2011)
Abstract

Backgrounds and Objectives:Owing to the fact that the major environmental problem is production of surplus sludge in wastewater treatment plant, reducing the volume of produced sludge was objective of this research.
Materials and Methods: An anaerobic-aerobic SBR with working volume of 10 L was used to make micro-organism adapted and a polymer production reactor (PPR) with working volume of 1.5 L was used for producing polymer munisipal wastewater which contained different concentration of volatile fatty acids was consodered as the feed source (acetate and propionate) and this system was evaluated with SRT of 5, 7 and 10 days.
Results: The maximum polymer production efficiency observed within 5 days (SRT=5 days) though this efficiency was not significant in comparison with the two others time courses study. In this research the maximum polymer production efficiency at optimum condition was 25% of the sludge dry weight.
Conclusion: Experiment revealed that producing polymer from activated sludge reduced the volume of sludge and the maximum reduced sludge volume was obtained 19%.


M.h Dehghani, S Nasseri, M Ghaderpoori, A.h Mahvi, R Nabizadeh Nodehi,
Volume 3, Issue 4 (1-2011)
Abstract

Backgrounds and Objective: Surfactants are one of the largest pollutants which exist in urban and industrial wastewaters. Large quantities of surfactants have entered to the environment since last decade due to increased use of synthetic detergent in industrial and home consumptions.In this study, the efficiency of UV/H2O2 process in removal of linear alkylbenzane sulfonate (LAS) from aqueous solutions was investigated.
Materials and Methods: In this study methylene blue active substane(MBAS)method and spectrometery were used to determine anion and residual surfactant respectively. In this study important variables were H2O2 concentration, initial concentration of surfactant, pH and duration of UV radiation. The effect of UV/H2O2 process on the degradation of LAS was analyzed statistically by using Multiple Linear Regression test.
Results: The resulted showed that after 20 minute, ultraviolet radiation solely removed 38.44 percent of Anionic detergent, Hydrogen peroxide showed no significant removal of detergent solution in the time course study. The efficiency of UV/H2O2 process in 10, 20 and 30 minute were to 86.2, 90 and 96.5 %, respectively.
Conclusion: The results showed that the efficiency of ultraviolet radiation and hydrogen peroxide process in anionic detergent was not significant thoogh it was considerable in combination process (UV/H2O2).


R Fouladi Fard, A.a Ebrahimi,
Volume 3, Issue 4 (1-2011)
Abstract

Background and Objective: Nickel (II) and cadmium (II) are important in environmental pollutant. Biosorption of heavy metals can be an effective process for the removal and recovery of heavy metal ions from aqueous solutions because of the decrease in sludge problems, economical issues, high efficiency and compatibility with the environment.
Materials and Methods: power of wasted activated sludge have been contact with nickel (II) and cadmium (II) solutions in 0.25 and 0.75 milli molar invarious pHs and mixing pace, at 24-26 0C temperature on batch reactor system .After two hours (continuously 5-420 min in kinetic study) samples were analyzed with atomic absorption spectrophotometer.
Results:The kinetic study results show that equilibrium adsorption time for nickel (II) and cadmium
(II) reached within 2 hr, but the profile curve of cadmium (II) biosorption was smoother than nickel (II) biosorption. Both metals adsorption followed the Langmuir model and the maximum adsorption capacity (qmax) for nickel (II) and cadmium (II) was 0.195 and 0.37 milli mole per gram respectively. The increase in pH resulted in adsorption increase for both metals. For cadmium (II) at 0.25 and 0.75 mMinitial concentration there was no adsorption at pH 2 where as nickel (0.25 mM) adsorption was observed at the same pH. The optimum mixing rate for both metals was 200 rpm and this effect was more obviously in greater concentration.
Conclusion: Like othe biosorbents ,wasted activated sludge showed greater capacity for cadmium(II) biosorption than nickel (II). Cadmium (II) in modeling and biosorption characteristics study had more conformity than nickel (II).


M Hadi, R Shokoohi, A.m Ebrahimzadeh Namvar, M Karimi, M Solaimany Aminabad,
Volume 4, Issue 1 (5-2011)
Abstract

Background and Objectives: widely use of antibiotics as therapy and uncontrolled discharge of them to receiving waters increased the percentages of antibiotic resistant bacteria in various environments which may cause problems in therapy. The aim of this study was to investigate the antibiotic resistance of E. coli, K. pneumoniae and P. aeruginosa bacteria isolated from urban and hospital wastewaters. Nine antibiotics namely Chloramphenicol, Ciprofloxacin, Trimethoprim Sulfamethoxazol, Gentamycin, Ceftizoxime, Nalidixic Acid, Ceftazidime, Ceftriaxon and Cefalexin were investigated in this study.
Materials and Methods: through a cross-sectional descriptive study the isolation of bacteria from hospital and urban wastewater samples was performed by microbiological identification techniques. The resistance to nine antibiotics was tested by application of the standard disc diffusion technique and zone-size interpretation chart of Kirby-Baeur. Non-parametric Mann-Whitney test was used to assessing two environments differences.
Results: The resistance percentage of E. coli to studied antibiotics was significantly less (ranged from 1.81 to 51.02%) than the resistance percentage of P. aeroginosa (ranged from 3.57 to 61.76) and K. pneumoniae (ranged from 6.45 to 91.83%). the highest resistance to antibiotics studied was for K. pneumonia in comparison with others. E. coli, K. pneumonia and P. aeroginosa bacteria showed the highest resistance to CAZ, SXT and CN, respectively. The study showed the resistance rate in hospital wastewater is more than urban wastewater.
Conclusion: Easy access and uncontrolled usage of antibiotics cause discharge of antibiotics to wastewaters and consequently diminish the drugs' effectiveness. High concentration of antibiotic and diversity in wastewater of hospital in comparison with urban wastewater causes to transfer resistant agents between bacteria and increased the multiple resistances.


M.h Dehghani, F Fazelinia, Gh.a Omrani, R Nabizadeh, K Azam,
Volume 4, Issue 1 (5-2011)
Abstract

Background and Objectives: Not paying attention to management and control of medical wastes in different stages of production, keeping, gathering, transporting and finally eliminating them all have been creating various setbacks such that the environment and human's health are in danger with the relevant consequences. This descriptive cross-sectional study was performed in Vali-e Asr, Amir Kabir, Taleghani, Amir Al-Momenin and Imam Khomeini hospitals of Arak city in 2009. In this research the current condition of gathering, maintaining, transportation and final elimination of hospital wastes of Arak city was investigated .Eventually an appropriate model was introduced.
Material and Methods: Solid wastes were separated, weighed and registered in two sequential intervals. In order to get acquaintance with the management procedure of medical solid wastes in the hospitals studied, a questionnaire approved byW.H.O was used. The questions were then replied by the Managers and Hygiene Experts worked at hospitals and their responses were recorded.
Results: The investigations conducted in 5 hospitals reveal that the average per annual was2.9 Kg in 24 hours per active bed and 4.6 Kg for each patient. This volume consists of 60% for semi-home solid wastes, 39% for infectious solid wastes, 0.34% for sharp wastes, 0.28% for the pathologic and 0.38% for medicinal and chemical solid wastes.
Conclusion: According to the results obtained in this study, in order to reduce pollution create in the hospitals, action should be taken to deal with pollutants at their source of generation. The staff members involved in waste collection and transportation should practice all the personal protection measures.finaly it also should be considered that,success in medical waste management wouldn't be achievable unless all groups of medical staff involved cooperate and participle.


Y Hamzeh, S Izadyar, E Azadeh, A Abyaz, Y Asadollahi,
Volume 4, Issue 1 (5-2011)
Abstract

Background and Objectives: The dyestuff manufacturing and textile industries consume a high volume of water and produce a great amount of wastewater containing various toxic substances. Different methods are used to remove dye compounds from wastewaters. Removal of dyes from water by adsorption processes received considerable attention and a number of studies focused on the adsorption of some dyes by non-conventional low cost and effective adsorbents. In this study, the suitability of the canola stalks for Acide orange 7 adsorption was assessed.
Materials and Methods: The dry canola stalks obtained from the research farm were milled and screened and the particles size ranged between 0.4-0.7mmwere used in all experiments. Acid orange 7 supplied by Alvan Sabet. Initially, the effects of initial dye concentration, pH and temperature on adsorption were examined. The kinetic and equilibrium data obtained for various concentrations of evaluated on the basis of Langmuir and Freundlich isotherms.
Results: The results showed that the absorption efficiency depended strongly on pH and slightly on the temperature. Absorption of acid orange 7 on the canola stalks was fairly rapid and more than 95% of adsorption occurred within the initial 5 minutes of the treatment. Both Langmuir and Freundlich models were applicable for the description of acid orange 7 dye adsorption by canola stalks.
Conclusion: According to the Langmuir model, the highest capacity of canola stalks for acid orange 7 adsorption was found 24.8 mg/g which was higher than the capacity of beech wood sawdust and soil mixture with fly ash.


M Pirsaheb, A Almasi, A.a Zinatizade, R Khamutian, S Delangizan,
Volume 4, Issue 2 (9-2011)
Abstract

Background and Objectives: Linear alkyl benzene sulfonates are widely used as surfactants in formulated detergent products. Because of their use in household and industrial detergents, LAS is discharged into wastewater collection systems and subsequently entered to wastewater treatment plants. Therefore, it is important to determine the concentration of LAS with accuracy. They are usually determined by standard method which is time-consuming,tedious and requires great quantities of chloroform. IN 2006 E.Jurado et al proposed a simplified method for measurement of LAS. In the present work the standard method and E.Jurado simplified method was compared economically.
Material and Methods: In this work NPV method was used for accounting the cost of initial investment, consumable material, non-consumable equipment and annual cost of staff and finally Net Present Value was calculated for them separately. The rate of interest was considered 15%.
Results: calculation showed initial investment, annual cost of staff and materials for standard method 13351981, 499968 and 1710981 RLS, respectively. And these costs for simplified method were 12048202, 83328 and 58202 RLS, respectively. Finally NPV for standard method and simplified method were equal to 30360709 and 14681848 RLS.
Conclusion: The method proposed by E.Jurdo et al is simple, time consuming and more economical than standard method .This technique can be suggested applying to the routine measurement of LAS in wastewater treatment plants.


M Ghani, F Golbabaie, A.r Akbarzadeh Baghban, H Aslani, N Moharamnejad,
Volume 4, Issue 3 (10-2011)
Abstract

Background and Objectives: Particular importance of hazardous wastes is due to having characteristics such as toxicity, flammability, corrosively and reactivity. Some of the chemical wastes due to having hazardous materials must be collected and managed in a proper manner, since they are potentially harmful to the environment. Owing to the fact that educational centers have important roles in developing countries, so the main objective of the present study was to investigate, hazardous waste management in chemistry laboratories of Ministry of Science universities, in Tehran, Iran.   
Materials and Methods: Study area of this research includes all chemistry laboratories in Tehran universities which were covered by Ministry of Science. To obtain the number of samples, based on Scientific Principles and identification formula, 64 samples were calculated. In addition, sampling was done by Stratified sampling. Validated checklists were used for data gathering. Data analysis were done by Descriptive statistics (mean, frequency and etc.) and inferential statistics (kruskal- wallis test).
Results: results obtained in this study indicate that Sharif University by obtaining the mean score of 60.5 and Tehran University by obtaining the mean score of 4.5-6 are placed in best and worst rank, respectively. Beheshty, Alzahra and Tarbiat Moallem univesities by acquiring the mean score of 20-28.5 have a same position in ranking table. 
Conclusion: Results show that most of the studied laboratories do not have any collection program and only 26.5 percent of them have acceptable programs.The separation and storing program observed in about 12.5 percent . Hazardous wastes' management in chemistry laboratory of Tehran Universities was not in good status. And from the standpoint of management, only 12.5 percent of studied cases are in good status, while 75 percent was in undesirable status.


M Gholami, A Sabzali, E Dehghani Fard, R Mirzaei, D Motalebi,
Volume 4, Issue 3 (10-2011)
Abstract

Background and Objectives: One of the complete treatment processes for industrial and municipal wastewater treatment is membrane bioreactor process which has dominant potential in process and operation sections. This study was conducted to compare the performance of extended aeration activated sludge (EAAS) with submerged membrane bioreactor (SMBR) systems in the treatment of strength wastewater, in the same condition.
Materials and Methods: The initial activated sludge was brought from the Plascokar Saipa wastewater plant. The Plexiglas reactor with effective volume of 758 L was separated by a baffle into the aeration and secondary sedimentation parts with effective volumes of 433 L and 325 L, respectively. The chemical oxygen demand (COD) concentration of the influent wastewater of the EAAS and SMBR systems were between 500-2700 and 500-5000 mg/L, respectively.
Results: Results showed that the SMBR system produced a much better quality effluent than EAAS system in terms of COD, biochemical oxygen demand (BOD5), total suspended solids (TSS) and ammonium. By increasing the COD concentration, the concentration of mixed liquor suspended solids (MLSS) and the removal efficiency of organic matter in the SMBR system, were increased regularly, however the removal efficiency of COD in the EAAS system was irregular. 
Conclusion: The average BOD5/COD ratio of effluent in the EAAS and SMBR systems were 0.708±0.18 and 0.537±0.106, respectively. These show that the organic matters in the effluent of the SMBR system was less degradable and thereupon more biological treatment was achieved. Nitrification process was completely done in the SMBR system while the EAAS system could not achieve to complete nitrification.

 


M.b Miranzadeh, M Sabahi Bidgoli, A.r Zarfeshani, M Heidari,
Volume 4, Issue 4 (3-2012)
Abstract

Background and Objectives Autoclaving is one of  the methods which sterilizes infectious solid wastes. Since variety of parameters such as temperature, time, and pressure influence autoclave performance, this study was carried out to evaluate the parameters and set optimum condition for the autoclave apparatus  applied in Shahid Beheshti Hospital in Kashan.
Materials and Methods: In this descriptive-analytical study, the performance of subjected autoclave was surveyed based on biological index and through setting 144 tests. Variables were packaging type in two groups (open and wrapped), loading type in three groups (light, medium and heavy), and four temperature-time features in fixed pressure equal to 101 kpa. Biological index was ATCC 7953 which contained Stearotermophilus Geobacillus spores. Finally obtained results were analyzed by Chi-Square test.
Results: The results of statistical test showed that there isn't any meaningful relation between packaging type of waste, system loading, and efficiency of sterilization(P>0.05),while meaningful relation was found between system performance and variety states of temperature-time feature(P<0.05), illustrating temperature and time effects in fixed pressure on sterilization of solid waste.
Conclusion: Based on the results, the best autoclave operational condition for sterilizing infectious solid wastes are: temperature-time equal to 10 min-140°C and 15 min-134°C in fixed pressure of 101 kpa, respectively. It was also revealed that temperature-time condition suggested by manufactory, i.e. 20min-121°C, is not sufficient for complete sterilization of solid waste.


M. A Karami, M Farzadkia, A Jonidi Jaafari, R Nabizade, M. R Gohari, M Karimaee,
Volume 4, Issue 4 (3-2012)
Abstract

Background and Objectives:  In recent years, poor industrial waste managements have created many crises in human societies. The aim of this study was to investigate industrial waste management located between Tehran and Karaj zone in 2009-2010.
Materials and Methods: This study is descriptive and sectional which was done by site visits, (Iranian environmental protection organization)  use of questionnaires, database production and results analysis. The questionnaire consisted of 45 questions mainly about industrial waste quantity, quality and management. Total number of industries with over 50 personnel's, calculated as 283. Class-weighted sampling was used in which the sample size contained 50 industries.
Results: Total generated industrial waste was 123451, kg per day. Major hazardous waste generated in industrial  sections included: chemical and plastic making. About 45.28% of waste generated disposed by private sectors. Landfill with 62% and reuse with 17% were the first and second alternative of common methods for final disposal of solid waste in this zone.
Conclusion: In order to reduce hazardous waste generation in this zone, reuse and recovery maximization of the waste must be noted in short-term. In long-term, some industries such as chemical-plastic and electronics which have high rate of hazardous waste production must be replaced with other industries with low rate production, such as wood-cellulose and paper industries.


R Khosravi, G.r Moussavi, Sh. Roudbar Mohammadi,
Volume 4, Issue 4 (3-2012)
Abstract

Background and Objectives: Effluent generated in several industries contains phenolic compounds, which have been classified as priority pollutants. Due to its toxicity, the conventional systems are inefficient for treatment of phenol-Laden wastewater. Biological processes using pure microbial culture, including fungi and yeast, are environmentally friendly techniques capable of complete destruction of contaminants.
Materials and Methods: This work was aimed at investigating the efficiency of a fungi specie in the decomposition of high concentrations of phenol ranging from 500 to 20000 mg/L. Several batch reactors were operated at different phenol concentration. The concentration of residual phenol was monitored over time using colorimetric method 4-aminoantipyrine. The removal efficiency was calculated considering the initial phenol concentration.
Results: Experimental data indicated that the phenol could efficiently degrade using the selected culture. The developed granules could completely degrade phenol at concentrations up to 20000 mg/L.
Conclusion: It can be concluded from the experimental data that the biodegradation using the Fungi granules is a very efficient and thus promising technique for treatment of wastewaters containing phenolic compounds.


A Khodadadi, H Ganjidoust, H Ijad Panah,
Volume 4, Issue 4 (3-2012)
Abstract

Background and Objectives: Many industrial effluent plants contain amounts of hard biodegradable compounds such as  β-naphthol which can be removed by conventional treatment systems. The objective of this research is to treat wastewater containing naphthalene by nano titanium oxide coated on activated carbon.
Materials and Methods: Photocatalytic experiments were carried out for different concentrations of β-naphthol using time and pH as dependent factors.  Nano TiO2 coated on activated carbone in one liter batch reactor and the resultants compounds' concentration were measured in a photocatalytic reactor  with UV-C of 12 Watt. 
Results: The experimental results indicated that UV/ nano TiO2  coated on activated carbone removed 92% of β-naphthol with concentrations of 100 mg/L within an overall elapsed time of three hours. β-naphthol total removal with concenteration of 25 mg/L was observed in two hours.
Conclusions: UV/ nano TiO2  process is very fast and effective method for removal of β-naphthol and  pH 11 was indicated as the optimum pH.


Z Kheradpisheh, H Movahedian Atar, M Salehii Najafabadi,
Volume 4, Issue 4 (3-2012)
Abstract

Background and Objectives: Cyanide is a highly toxic compound which is Normally found in numerous industries, such as electroplating wastewater. Release of this compounds in to the Enviroment has a lot health hazards.The Purpose of this study is to Determine the efficiency of electrochemical oxidation method for Cyanide removal from industrial wastewaters

Materials and Methods: This study conducted in a pilot system experimentally .In this study the effect of pH, voltage and operation time on total cyanide removal from industrial wastewaters by Electrochemical Oxidation was investigated by applying a Stainless Steel as a Anode and copper as a cathode .

Results: The average percentage removal of cyanide was about 88 with SD=2.43. The optimal condition obtained at voltage of 9V and pH=13 and The operation time of 90 minutes.The volume of sludge which formed in this condition was  about 20 percent of a one liter pilot reactor.

Conclusion: the results statistically confirmed the significant relationship between

input and cyanide concentration removal efficiency (p< 0.05), and confirmed  The this confirmed The  relation between cyanide & cyanat oxidation and hydroxyl ions consumption 1:2.( L.Szpyruowicz). therefore the best pH is 12.5-13.5 by Considering the need  of alkaline environment to remove cyanide.

M Malakootian, M. M Amin, H Jaafari Mansourian, N Jaafarzadeh,
Volume 4, Issue 4 (3-2012)
Abstract

Background and Objectives: Microbial fuel cells are the electrochemical exchangers that convert the microbial reduced power, generated via the metabolism of organic substrate, to electrical energy. The aim of this study is to find out the rate of produced electricity and also treatment rate of simulated wastewater of food industries using dual chamber microbial fuel cell (MFC) without mediator and catalyst.
Materials and Methods: MFC used in this study was consisted of two compartments including anaerobic anode chamber containing simulated food industries wastewater as synthetic substrate and aerobic cathode chamber containing phosphate buffer, respectively. These two chambers were separated by proton exchange membrane made of Nafion. Produced voltage and current intensity were measured using a digital ohm meter and the amount of electricity was calculated by Ohm's law. Effluent from the anode compartment was tested for COD, BOD5, NH3, P, TSS, VSS, SO42- and alkalinity  in accordance with the Standard Methods
Results: In this study, maximum current intensity and power production at anode surface in the OLR of 0.79 Kg/m3.d were measured as 1.71 mA and 140 mW/m2, respectively. The maximum voltage of 0.422 V was obtained in the OLR of 0.36 Kg/m3.d. The greatest columbic efficiency of the system was 15% in the OLR of 0.18 Kg/m3.d. Maximum removal efficiency of COD, BOD5, NH3, P, TSS, VSS, SO42- and alkalinity, were obtained 78, 72, 66, 7, 56, 49, 26 and 40%, respectively.
Conclusion: The findings showed that the MFC can be used as a new technology to produce electricity from renewable organic materials and for  the treatment of different municipal and industrial wastewaters such as food industries.


Fazlollah Changani, Anvar Asadi, Gholam Ali Haghighat, Amir Hossein Mahvi,
Volume 5, Issue 1 (4-2012)
Abstract

MicrosoftInternetExplorer4 Background and Objectives: since there is not any information about the quality and quantity of carpet cleaning wastewater, this study was done for the evaluation of carpet cleaning wastewater   characterization in Tehran.
Materials and Methods: There are 122 carpet-cleaning units in Tehran. Compound samplings were taken from 10 randomly selected carpet-cleaning units. Each unit was sampled 5 times and analyzed based on the Standard Methods. Quality parameters measured included chemical oxygen demand (COD), detergent, color and suspended solids (SS), and data was analyzed using statistical software spss16.
Results: Results showed that the amount of water usage for carpet cleaning was 30.84 liters per square meter of carpet washed. The average level of COD, color, detergent and SS in the effluent of carpet cleaning unit was 367.4   mg/l, 171.85 ADMI, 55.51 mg/l and 359.62 mg/l, respectively.
Conclusion: The effluent characteristics of carpet cleaning units are almost with in the domestic wastewater range. However, since these wastes are disposed untreated into the environment which are then enter surface and groundwater, all measured parameter were higher than proposed standards regulated by EPA, So treating process must be done before disposal.

!mso]> ject classid="clsid:38481807-CA0E-42D2-BF39-B33AF135CC4D" id=ieooui>



Page 2 from 8     

© 2024 , Tehran University of Medical Sciences, CC BY-NC 4.0

Designed & Developed by: Yektaweb