Search published articles


Showing 153 results for Waste

Mr Mehrasbi, Z Farahmand Kia,
Volume 1, Issue 1 (10-2008)
Abstract

Background and Objectives: Heavy Metals in Water resources is one of the most important environmental problems of countries. Up to now various methods of removing of these metals is considered, which is including using of low prices materials. In this study the potential of banana shells was assessed for adsorption of heavy metal ions such as Pb and Cd from aqueous solution.
Materials and Methods: Banana shells were pretreated separately with 0.4 mol/L NaOH, 0.4 mol/L HNO and distilled water and their adsorption ability were compared. Batch adsorption experiments were carried out as a function of the initial ion concentration, pH and adsorbent dosage. Adsorption isotherms of metal ions on adsorbents were determined and correlated with common isotherm equations such as Lungmuir, Freundlich and BET models.
Results: The maximum adsorption capacities were achieved by alkali modified banana shells (36 mg/g) for Pb and by acidic modified banana shells (16 mg/g) for Cd. Experimental results showed that the best pH for adsorption was 6 and the adsorption values decreased with lowering pH. Isotherm models indicated best fit for Freundlich model for modified banana shells.
Conclusion: In comparing the parameters of models, it was observed that the capacity of banana shells for adsorption of lead is higher  than for adsorption of cadmium, but the adsorption of  cadmium is stronger than the adsorption of lead.


Ms Hassanvand, R Nabizadeh, M Heidari,
Volume 1, Issue 1 (10-2008)
Abstract

Background and Objectives: In the recent years Municipal Solid Waste (MSW) has been one of the most important environmental concerns to throughout regions of Iran. Sound MSW management for any area needs to the reliable data in which present the actual MSW condition in that area. The aim of this study is express of integrated view of MSW in Iran.
Materials and Methods:  In this study we collect the data from various municipal regions of Iran, to represent the roughly integrated view of MSW management situation in Iran. In this paper quantity, average generation rate, physical composition, and types of disposal methods in all of municipal regions of Iran also were investigated.
Results: Results from this study has shown that the amount of MSW generated in all of the municipal regions of Iran was 10370798 tons per year, and the average generation rate of MSW was 0.64 kg/capita/day. Results showed that only 6% of MSW was recycled, 10% was treated at organic waste (composting) plants, and about 84% was disposed of in landfill.
Conclusion: According to obtained results from this study and compare  MSW composition of Iran to some countries, its found that MSW properties in Iran is near to MSW properties in Low-income countries. Since the most of MSW in Iran contain organic fraction, there is a high potential to develop of composting industry.


R Rostami, A Nabaey, A Eslami,
Volume 1, Issue 2 (3-2009)
Abstract

Background and Objectives:Nowadays vermicompost production of food wastes is posed as one of appropriate methods to food wastes. disposal, its production used in agriculture and gardening. Moreover this process has some by products beside useful fertilizer that one of them is the worms. we can use them in variety of products specially in production of poultry and fish food. So determination of optimal condition for operating vermicompost production process of food wastes and worms. growth in these wastes is important. The aim of this study was determination of optimal temperature and moisture range for process progression in vermicompost production of food wastes.
Materials and Methods: In this study we used Eisenia foetida species. Process performed in pots with 15 cm (h) and 12 cm (d) and in a mouth period of time. Three ranges of temperature including 5-15, 15-25, 25-35 oC and three ranges of moisture including 55-65%, 65-75%, 75-85% were applied in this study.
Results: Multivariate analysis was used for analyze of results and it showed that influence of temperature and moisture on C:N ratio is significant in vermicomposting process (p <0.05).
Conclusion: The results showed that the range of temperature 15-25 oC is more appropriate for operating of process. Due to these study.s results with increasing or reduction of ambient temperature, like summer and winter, conservation of moisture around the range of 65-75 %, is effective in better performance of the process. According to this study.s results, it seems that the temperature of 15- 25 oC and moisture of 65-75% are better conditions for worm.s growth.


M.a Zazouli, A Mohseni Bandpei, A Eslami, A Sadeghi,
Volume 1, Issue 2 (3-2009)
Abstract

Background and Objectives: Recycling is one of the best alternatives in solid wastes management.  Recycling has few benefits from the viewpoint of economics and environmental. Paper and cardboard are the valuable recyclable materials in solid wastes. The rate of paper recycling is 35% in world. The major production source of paper and cardboard wastes is private and governmental offices and organizations. To be informed about paper production is very important in the solid wastes recycling.Thus, the aim of this study was to determine production rate of paper and cardboard waste and also to determine paper recycling potential in the 20 head offices of Mazandaran province.
Materials and Methods: This study was conducted in the 20 head offices of at province center. The  offices were selected by chance. This study was conducted four months in 2006. paper waste was separated after suspension of work. Collected material weighed on the sensitive scales. Separation and measuring was done for a week per month.
Results: The results showed that more than 2 tons of paper waste was produced in the twenty offices.  The maximum and minimum of paper production was in education and recycling organization, respectively. The maximum and minimum of production rate was 2.08 and 0.192 kg per capita in month that was in the education and Jihad-e-Agriculture organization, respectively. Also the maximum and minimum of paper waste was produced at first work day of week (Saturday) and last work day of week (Thursday), respectively. However, it was not significantly (P >0.05). Paperrecycling operation and marketing was done in an office.
Conclusion: Findings of this study indicated that office solid waste management needs more notice  in Iran. And also calculations showed that paper recycling is economical.


G Moussavi, A Jamal, H Asilian,
Volume 1, Issue 2 (3-2009)
Abstract

Background and Objectives: A conventional treatment to stabilize the excess activated sludge is the aerobic digestion process but due to long aeration time, it requires large equipments as well as high investment cost. Because of high oxidation potential of ozone, sludge ozonation enhances stabilization rate and reduces sludge treatment equipment size and cost. Therefore, in this study, the combination of pretreatment with ozone and aerobic digestion processes were investigated.
Materials and Methods: The experimental set-up consisted of an ozone generator and ozonation reactor with the total volume of 2 L. Removal percentages of TSS, VS, total and soluble COD, HPC, fecal coliform and settable solids were measured in integrated process compared to the single ones.
Results: The results of this research indicated that the aerobic digestion of waste activated sludge during 10 days could reduce 38% of volatile solids and thus obtaining the EPA standard. Also, the results of combined ozonation and aerobic digestion revealed that the pre-ozonation at 0.25 g O3/g TS or 0.5 g O3/g TS with 6 or 3 days aeration, respectively, could achieve 38% reduction in VS and hence the requirement set by EPA. Therefore, integration of pre-ozonation with aerobic digestion can significantly reduce the digestion time to attain the standards.
Conclusion: The sludge pre-ozonation with low dose of ozone due to solids disintegration can enhance the efficiency of aerobic digestion in waste activated sludge stabilization, and consequently decrease size of equipments, air requirement, investment and probably operation cost.


M Aghanejad, A.r Mesdaginia, F Vaezi,
Volume 2, Issue 1 (7-2009)
Abstract

Backgrounds and Objectives: Now a days modified activated sludge ways are used for standard removing nutrient substances from waste water that is named Enhanced biological phosphorus removal One of the most suitable ways is Anoxic-Oxic(A/O) process. The goal of this research is investigation and solving existing problems of Khoy power plant(P.P) waste water treatment plant(WWTP)and optimizing of phosphorus removal in it.
Materials and Methods: This research is done full scale in this treatment plant. The treatment plant was operating with extended aeration process, and some problems had, so in the first stage with in investigation of total efficiency, problems and their reasons determined. In the second stage after operational modifications existing problems was solved and real efficiency of treatment plant particularly for phosphorus(P) removal determined. In the third stage changes, system converted to A/O process and new system was tested with Changing parameters like food/microorganism(F/M), return sludge ratio(RAS)and sludge retention time(SRT)
Risults: In the first stage the most important problems were over concentration of BOD,TSS, and P in effluent of treatment plant and overgrows of alga observed in parts of treatment plant and effluent receiving conduit. The main reason of high concentration of P was considered releasing of sludge. In the second stage operating condition modification efficiency of P removal increased from 50to 62 percent. In the end of third stage value of P removal reached to %82 and the most suitable of anoxic contact time was determined 3to4 hours, SRT terry day and F/M ratio o.12,that the most effective change has been the decrease of SRT to three days.
Conclusion: Adjusting of operating factors like SRT,RAS, sludge processing way in WWTP can increase P removal in them with in total efficiency remaining, such as in this case it was %12. In waste water treatment particularly for P removal the A/O process is suitable so in this project its effect on P removal efficiency has been %20.


M. T Ghaneian, Gh Ghanizadeh,
Volume 2, Issue 1 (7-2009)
Abstract

Background and Objectives: Phenolic compounds are presence in many industrial wastewaters, and have been classified as priority pollutants. Application of several conventional processes due to high cost and low efficiency has been limited. Thus, new methods such as enzymatic polymerization seem to be preferable and effective processes with high potential to substitute the conventional processes. This study was carried out to evaluate Raphanus sativus extract as a peroxides enzyme source for polymerization and removal of phenol from synthetic wastewater in the presence of hydrogen peroxide.
Materials and Methods: The study was performed in batch reactor at room temperature. Peroxidase enzyme was extracted from Raphanus sativus plant roots . Primary concentration of phenol in wastewater was 100 mgl-1. The concentration of phenol and enzymatic activity was been measuredby photometric assay.
Results: The results show that Raphanus sativus extract is a suitable source of peroxidase enzyme. Mean enzymatic activities in this extract was 3.107 Uml-1. Also, our results showed that elevation of extract volume lead to high efficiency of phenol removal, in which the increase in the extract volume from 5 to 50 ml, resulted in the efficiency of processes increased from 7.6 to 98.2 %. Also, sequencing addition of H2O2 and extract has improved the effects. The phenol removal efficiency of the reaction time after 3 h with single and three stages adding of reactants was 84.2 and 93.1% , respectively.
Conclusion:Enzymatic polymerization can be used as an appropriate process for the removal of phenolic compounds from wastewaters. To meet the optimized condition in process, the ratios of phenol/ enzyme and H2O2/ phenol and sequences of the adding of reactants should be considered.


A Kulivand, R Nabizadeh, A Joneidy, M Yunesian, Gh Omrany,
Volume 2, Issue 1 (7-2009)
Abstract

Backgrounds and Objectives:Today, One of the most important environmental issues is solid waste Produced in Dentistry That because of the presence of hazardous, toxic and pathogen agents has special importance. In this survey, solid waste produced in Hamadan Dentistry laboratories and practical dentist offices is studied.
Materials and Methods: In this descriptive study, from 24 Dentistry laboratories in Hamedan 5 offices and from 27 practical dentist offices 5 offices were selected in simple random way. From each offices 3 sample at the end of successive working day (Sunday, Monday and Tuesday) were analyzed. Samples were manually sorted into different 41 components and by means of laboratory scale were measured. Then, measured components were classified based on characteristic and hazardous potential.
Results: Total annual waste produced in Dentistry laboratories and practical dentist offices in Hamaden is 15921.79 and 8677.56 Kg respectively. Production percentages of domestic type, chemical and pharmaceutical waste, potentially infectious and toxic wastes in practical dentist offices were 91.14, 6.7, 2.14 and 0.02 respectively. Dentistry laboratories solid waste comprises of 94.47 percent domestic type and 5.53 percent chemical and pharmaceutical waste. Main components of produced analyzed wastes were 2 components that consist of more than 80 percents of total dental solid waste. So, waste reduction, separation and recycling plans in the offices must be concentrated on these main components.
Conclusion: In order to waste suitable management, it is suggested that in addition to educate waste producer for waste reduction, separation and recycling in the offices, each section of dental waste (toxic, chemical and pharmaceutical, potentially infectious and domestic type wastes) separately and according to related criteria are managed.


N Jaafarzadeh Haghighifard, M.m Mehrabani Ardekani, R Nabizadeh Nodehi, A.r Yazdanbakhsh,
Volume 2, Issue 1 (7-2009)
Abstract

Backgrounds and Objectives: in recent years, mobile bed biological reactors have been used progressively for municipal and industrial wastewaters treatment. Dissented experiment is a trial that significant changes will accrue for influent variables in the process, and generally used for identification of the effective factors and optimization of the process. The scope of this study was determination of the optimized conditions for the MBBR process by using of Taguchi method.
Materials and Methods: Reactor start up was done by using of the recycled activated sludge from Ahwaz wastewater treatment plant. After that and passing the acclimation period, with hydraulic residence time equal to 9 hours matched for 1000, 2000 and 3000 mg/l based on COD respectively, for optimization determination of the acclimated microbial growth, the variables change (pH, nitrogen source, chemical oxygen demand and salinity) were determined in 9 steps, and all of the results were analyzed by Qualitek -4 (w32b).
Results:In this study, organic load removal based on COD was 97% and best optimized condition for MBBR were (inf. COD=1000 mg/l, pH= 8, salinity = 5% and the Nitrogen source= NH4CL)
Conclusion: Based on our finding, we may conclude that Taguchi method is on of the appropriate procedure in determination the optimized condition for increasing removal efficiency of MBBR.


A.h Sayyahzadeh, M.t Samadi,
Volume 2, Issue 2 (9-2009)
Abstract

Backgrounds and Objectives: Municipal Solid Waste (MSW) management and planning without  adequate and reliable data about its physical components and generation rate are not obtainable. Because of MSW collection and landfilling expenses, in last decades, reuse and recycle of its components as an environmental object have been considered.
Materials and Methods:In this research, in order to determine the possibility of source recycling application in Malayer and physical composition of MSW, samples were taken by Truck-Load method and cluster random sampling from autumn 2006 until summer 2007 and analyzed for physical components percents. The obtained data were analyzed by One-Way ANOVA and Tuky statistical test. Also, public partnership was investigated. Public opinion deliberation was accomplished by dividing the city into several clusters. Questionnaires were filled by oral interview conversation.
Results: The results showed that average daily generation rate was 138 Tons and 0.88 Kg per person per day. The average percent of recyclable materials was about 11% of total daily generated wastes. Also 99% of residents had positive response to source recycling plans.
Conclusion: In general, by planning of enforceable reuse and recycling programmes, could avoid  of 15 Tons of recyclable materials burial and save 19 millions Rials each day.


Gh Ghanizadeh, Gh Asgari,
Volume 2, Issue 2 (9-2009)
Abstract

Backgrounds and Objectives: Dyes  are  organic  materials  with  complex structures, toxic,  carcinogenic, teratogenic,nonbiodegredable properties and!the most!important pollutants of textile industrial wastewaters. The goal of this study was to survey the feasibility application of bone char (BC) as a sorbent for the  of methylene blue (MB) from synthetic wastewater.The sub goals of the research!were to determine!the adsorption isotherm, !effects of primary concentration of dye, adsorbent!dose, contact!time, and pH for the adsorption of MB with BC.
Materials and Methods: BC was prepared under laboratory conditions by using of electrical furnace at 400°C for 2h. The prepared BC was crushed and pulverized by standard ASTM sieves with range of 10-16mesh(1.18-2mm).The  chemical composition  and  solid  structure  of BC was  analyzed using X-ray diffraction(XRD) and  scanning  electronic  microscopy (SEM). Measurement  of  the surface area was carried out by N2 gas via BET isotherm and Belsorb software. The concentration of dye was measured by photometric!method (663nm).
Results: Predominant!compositionof BC is calcium hydroxyl apatite (Ca5 (PO4)3OH with 14m2/g surface area. The results of this study showed that increasing of primary concentration of dye, adsorbent dose and pH (5 to12) would lead to increasing of adsorption/removal of MB dye.Equilibration of dye adsorption was reached at lapse of 2h andoptimum pH for adsorption of MB with BC found in the rage of 8.5-12.Adsorption of MB witht BC complies witht freundlich isotherm(R2:0.99).
Conclusion: Bone char is a cheap component that can be used as an adsorbent in water and wastewater treatment. Based on optimum pH of 8.5-12 found for the removal of MB and the fact that many of textile!industrial wastewaters have an alkaline pH, this adsorbent can be!used for the removal of dyes from these wastewaters.


K Naddafi, R Nabizadeh, M.s Hassanvand, A.r Mesdaghinia, K Yaghmaeian, F Momeniha,
Volume 2, Issue 3 (11-2009)
Abstract

Backgrounds and Objectives: Due to having features such as toxicity, corrosiveness, ignitability, reactivity or other similar characteristics, hazardous wastes refer to the wastes that jeopardize man's health and environment. A study was required to identify the hazardous wastes in Tehran University of Medical Sciences (TUMS), since it plays an important role in the development of the country's education. The objective of this research was to provide a review of hazardous wastes production and its management at Tehran University of Medical Sciences.
Materials and Methods: In this study, four schools that were in the central campus of Tehran University of Medical Sciences, Iran, were selected and the necessary data were gathered using a sampling, questionnaire, interviewing those in charge of the units, and referring to the available documents. The information includes the type and amount of waste, method of temporary storage, frequency of waste discharge, and method of final disposal of wastes.
Results: The obtained results indicate that approximately 2072 Kg of hazardous wastes are produced each year, excluding the uncontrolled wastewater. Moreover, schools of dental, pharmacy, medicine, and public health produced approximately 993, 606, 256, 217 Kg/year, respectively, of hazardous wastes in the central campus. Also, the results show that, of total amount of annual hazardous waste that was 2.72 tons, 954, 848, 475, 427, 245, 49 Kg were wastes that the features infectious, toxicity, ignitability, carcinogenesis, corrosiveness, and reactivity, respectively.
Conclusion: It  is to be mentioned that hazardous solid wastes were manage with household solid waste and hazardous liquid waste were discharged into sink without any kind of control. Improper practice is evident from the point of waste production to final disposal.


M Farzadkia, S Salehi, A Aameri, A Joneidy Jafari, R Nabizadeh,
Volume 2, Issue 3 (11-2009)
Abstract

Backgrounds  and Objectives:  Over than 70% of solid wastes is consisted of food wastes with high putrecibility in Iran.  Due to this regard, construction of composting factories for sanitary disposal or fertilizer production from solid wastes was very appreciated in our country. The objective of this research was to study on the quality and comparing of the compost produced by Khomain and Tehran compost factories.
Materials and Methods: This study was accomplished on the compost produce from Khomain and Tehran compost factories about 9 months. For investigation of chemical qualities of these materials, some indexes such as percentage of organic materials, carbon, nitrogen, phosphorus, potash and heavy metals consists of lead, cadmium, mercury and chromium were measured. Microbial quality of these compost materials were defined by assessing of the amounts of coliforms bacteria, salmonella bacteria and parasites ova.
Results: The average amounts of some indexes in compost of Khomain and Tehran were been: organic materials % (37.77, 29.80), carbon %( 22.14, 18.12), nitrogen% (2.08, 1.6), lead (229.6, 59.44 ppm), and chromium (70.2, 19.75), respectively. The microbial quality of these compost samples were agreement with class B of USEPA guidelines.
Conclusion: This study showed that quality of organic materials percent in Tehran's samples was better than Khomain's samples, but these indexes on these samples were lower than the grade No.2 of compost. The percentage of carbon, nitrogen and potash in these samples were desirable but, phosphorus amount were not in sufficient. The heavy metals especially lead and chromium in Tehran's samples were higher than Khomain's samples, but these samples were usually in agreement with guidelines of compost. Due to the defined microbial qualities, these samples could be used as well as amendment agents for poor soil.


A.r Yazdanbakhsh, A Sheikh Mohammadi, M Sardar, H Mohammadi, M Zarabi,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives: A great part of organic compounds cause more pollution in natural  waters meet, are chemical dye material. Azo dyes have more usage in different industries. Azo dyes not only give undesirable dye to the water but also have mutation potential and carcinogenesis effects in human and cause the production of toxic substances in water environments.The purpose of this study is investigation of iron powder, hydrogen peroxide and iron powder-hydrogen peroxide processes in removal of acid yellow 36 dye from aqueous solutions.
Materials and Methods: This study was conducted in laboratory scale. At this experiment synthetic solution was made from acid yellow 36 dye, and the removal of acid yellow 36 dye was studied by iron powder, hydrogen peroxide and iron powder- hydrogen peroxide processes .Also effect of dye concentration, pH solution, hydrogen peroxide concentration, iron powder concentration and the time of contact on decolorization, were evaluated.
Results: The results showed that iron powder - hydrogen peroxide process, compared to two other  process has high decolorization power. Removal efficacy of iron powder-hydrogen peroxide process with H2O2 =23.33 ml / L, pH =3, iron powder 2000 mg/L and 60 minute ,was about 97.9%
Conclusion:In general this investigation showed that , this method (Iron powder-hydrogen peroxide process) has high efficiency for removal of Azo dyes. But application this method in the industry, should be economically evaluated.


M Panahandeh, M Arastou, A Ghavidel, F Ghanbari,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives: Landfill site selection is an important action in integrated solid waste management process. Difference criteria should be paid attention in site selection, so using of special methods are necessary to assimilate the criteria. In this research, GIS software and Analytical Hierarchy Process were used.
Materials and Methods: First of all, maps were built in considering to economical, social and environmental factors, in next step, each layer, was graded. Low grade showed non coordination or less coordination and high grade showed more coordination.
Results: Assimilate of graded map in AHP process, separates area into unsuitable, suitable and very
suitable parts.
Conclusion: Very suitable parts can have high priority in decision making and also suitable parts can have high priority for development projects in future.


N Jaafarzadeh Haghighi Fard, A.r Talaiekhozani, M.r Talaiekhozani, S Jorfi,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives:Propylene glycol is applied in many industries as raw material and can be released to the environment through wastewater of such industries. The biological treatment of solutions containing high concentration of propylene glycol is difficult and some problems can be observed during this process. The main objective of this study was the investigation of electrochemical degradation of propylene glycol and the parameters influencing on improving removal efficiency.
Materials and Methods: In this study the degradation of propylene glycol was made by passing an electrical current though the synthetic wastewater containing propylene glycol. In order to investigate this process several types of electrode with applied voltage ranging between 5 to 50 V was used. Due to the effect of NaCl concentration on removal efficiency which was mentioned in the literature, the experiment was performed for different NaCl concentrations.
Results: In optimum condition, the maximum removal efficiency of propylene glycol (based onCOD) was obtained equal to 90%. The results showed that rising applied voltage, NaCl concentrationand retention time increase the removal efficiency. The optimum retention time was obtained equalto 50 min. The maximum removal was obtained when aluminum electrode was used. It can beattributed to the production of coagulant material such as Al+3 during this process.
Conclusion: The results revealed that this process can be useful for treating the industrial wastewatercontaining propylene glycol.


A. Almasi, A.h Hashemian, E. Amirpour, A. Dargahi, M. Mahmoudi,
Volume 3, Issue 1 (4-2010)
Abstract

Backgound and Objectives: The aim of this study is to investigate water consumption, domestic wastewater generation and organic matter concentration, based on both, economical income and meteorological temperature.
Materials and Methods: The method of this study is descriptive and analytical. A checklist was used to collect data on economical income. Water consumption was obtained based on water bills. Wastewater generation and organic matter such as biochemical oxygen demand (BOD) per capita/ day were measured every four hours, during a day in three regions of Kermanshah city: Kasra, Ellaheiah and Taavon.
Results: Comparing water consumption in winter and summer showed significant difference in three regions, mentioned above. The water consumption was (398 ± 75, 291 ± 48 and 188 ± 50) for warm climate and (200 ± 25, 188 ± 35 and 140 ± 41) for three regions respectively in cold weather. In spite of an apparent difference in BOD in three regions, it was not significant statistically. Water consumption has strongly considerable relationship with economical income (r =0.988, P_value <0.001), while the generated wastewater in these regions were not different, statistically for warmclimate (220 ± 60, 204 ± 15 and 170 ±34), and in cold weather (170 ± 21, 158 ± 31 and 112 ±29), also the generated wastewater did not have considerable difference in cold climate. This study confirms that, the effects of these two parameters, i.e.monthly economical income and environmental temperature on water consumption, generated wastewater and biodegradable organic loading per capita/day is considerable. It was concluded that water consumption and wastewater generations were much more in warm climate than in cold weather.
Conclusion: Finally through this study the estimation of water consumption, wastewater generation and BOD concentration becomes possible, which is beneficial for establishment of water consumption.


H. Asilian, G.r Moussavi, M. Mahmoudi,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds and Objectives:Much attention has been recently paid on using waste materials as adsorbents for removal of contaminants from water and wastewater. A new low cost waste was examined for its capacity to adsorb RR198, an azo reactive model dye, from an aqueous solution.
Materials andMethods: The waste was dried, powdered and characterized before being used as an adsorbent. The effects of pH (3-10), adsorbent dose (0.2-3 g), dye concentration and contact time on the adsorption efficiency were investigated. Equilibrium study data were modeled using Langmuir and Freundlich models.
Results: The characterization analysis indicated that itwas composedmainly of ferric hydroxide. The powder had a BET and average pore size of 107 m2/g and 4.5 nm, respectively. The results showed that dye removal was highest at a solution pH of 7 to 8 and a powder dose of 2 g/L. The RR198 removal percentage decreased from 100& to 43& at 140 min contact time when the concentration of dye was increased from 25 mg/L to 100 mg/L, at optimum pH and dosage. The Langmuir equation provided the best fit for the experimental data. The maximum adsorption capacity was calculated to be 34.4 mg/g.
Conclusion: According to the obtained results, the water coagulation waste sludge appears to be a suitable low cost and effcient adsorbent for removing reactive azo dyes from waste streams.


M.a Zazouli, E. Ghahramani, M. Ghorbanian Alahabad, A. Nikouie, M. Hashemi,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds and Objectives: One of environmental outcomes in industrial towns is developing environmental pollution such as production of industrial wastewaters. These industrial wastewaters should be appropriately treated before entering to receiving waters. However we can't solve environmental anxieties by establishing of wastewater treatment plants alone but permanent and regular assessment of these treatment plants performance is necessary for achieving environmental standards. Thus, this research has been done in order to investigation of activated sludge performance in wastewater treatment of Agghala industrial town in Golestan province.
Materials and Methods: This cross-sectional study implemented in sewage treatment plant laboratory of Agghala industrial town in Golestan within 12 months at 2007. Chemical Oxygen Demand (COD) parameter determined twice in week, But Biochemical Oxygen Demand (BOD) test accomplished weekly. pH measured by pH meter daily. Experiment of total suspended solids (TSS) and total dissolved solids (TDS) carried out every 10 days. All tests accomplished according to standard method for water and wastewater examination (2005). Then data analyzed using excel 2007.
Results: The average of BOD, COD and TSS in influent was 11196.17, 1854.58, 1232.25 mg/L respectively.Maximum influent organic loading rate was related to Shahrivar andMehr months. The total average of removal efficiency for BOD, COD and TSS was calculated 99.66, 98.2, and 97.6% respectively.
Conclusion:Quality of this treatment plant effluent was according to effluent disposal standards all over year. In sum, efficiency of this treatment plant (activated sludge system) was very good ininfluent pollutant removing. However occasionally effluent was not adapted with environmental standards but these deficiencies is solvable by accurate management and supervision on flow rate and influent organic loading rate easily.


R Dehghanzadeh, H Aslani, B Afshar Forugh Shams, B Ghoraishi,
Volume 3, Issue 2 (7-2010)
Abstract

Backgrounds and Objectives: Shortage of available water resource and deficiency of rainfall, increasing in population growth and industrial development, suitable use of water resources and pollution prevention is an essential issue in accord with sustainable development and environmental protection. Present study shows the qualitative status ofMehran River and determines its pollution or non pollution tomunicipal wastewater and to assess qualitative characteristics of the water according to international water quality index.
Materials and Methods:Padding strand of MEHRAN River from source to end has been done for wistful determination of branches, runoff and wastewater entrances, etc. Necessary decisions were made for determining sampling points and critical and effective points on water quality then water samples were analyzed to determine chemical and microbiological characteristics.
Results: Results showed the average of BOD5, COD, TSS, NO3, DO, pH, Turbidity and color are about 80±30, 155±58, 1013±637, 7.3±2, 4.5±3.5 mg/l, 7.2 ±1, 385±238 NTU, 122±70 TCU respectively.
Conclusion: It could be concluded that the Mehran River is completely polluted with municipal sewage and is unsanitary.Water quality index varies in the range of 41-52 and the water is classified as number 4. At present the river is in a dangerous ore toxic state and could not be considered as drinking water resource or needs more advanced water treatment units.



Page 1 from 8    
First
Previous
1
 

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

Designed & Developed by: Yektaweb