حسین موحدیان عطار

In recent decades, there has been a growing concern about the presence of antibiotics in water resources. The presence of these micropollutants even in low concentrations has significant effects on the environment and human health, and their entry into the soil and especially receiving waters should be prevented as much as possible. As effluents from wastewater treatment plants (WWTPs) are significant sources of antibiotics in the environment, this study aimed to investigate the efficiency of antibiotics removal in municipal WWTPs.

In this study, Isfahan East WWTP with a combination of stabilization ponds and an aeration lagoon, and Isfahan South WWTP with conventional activated sludge treatment were selected as well as four antibiotics from the beta-lactam group including ampicillin, amoxicillin, cephalexin, and penicillin, and their removal efficiency was investigated in both WWTPs. Samples were collected from the influent and effluent of both WWTPs on 13 occasions and analyzed immediately after being transferred to the laboratory. The concentration of antibiotics was determined by high-performance liquid chromatography (HPLC).

In the Isfahan East WWTP, the average removal efficiency was 86.22 ± 19.84% for ampicillin, 34.35 ± 31.38% for amoxicillin, 78.75 ± 23.81% for cephalexin, and 89.80 ± 19.42% for penicillin. In the Isfahan South WWTP, the average removal efficiencies of amoxicillin, ampicillin, cephalexin, and penicillin were equal to 54.82 ± 33.29%, 66.85 ± 24.88%, 87.65 ± 21.76%, and 82.76 ± 21.85%, respectively.

The study's findings revealed that Isfahan municipal WWTPs were unable to fully eliminate antibiotics. According to statistical analysis, there were significant differences in the concentration of antibiotics in both WWTPs, and no critical correlation was observed between the removal efficiency of antibiotics and other principal wastewater parameters. Consequently, there is a need for stricter control over the discharge of effluent into the river or its use for agricultural irrigation.

Industrial wastewater treatment has always been difficult and costly due to the presence of different and high concentrated pollutants. The use of constructed wetlands is economical due to the need to use no external energy sources and materials and equipment to reduce pollutants. The aim of this study was to determine the efficiency of horizontal and vertical subsurface wetlands in the removal of pollutants from the wastewater of the Mourchekhort Industrial Estate and its comparison with performance of the conventional coagulation-flocculation-filtration unit of reuse process.

Two horizontal and vertical wetlands in pilot scale and two control (no plant) reactors were operated for eight months. Removal efficiency of TSS, COD, turbidity, phosphorous and nitrogen compounds and index bacteria were evaluated. Horizontal wetlands with dimensions of 0.8 × 0.65 × 2 m and floor slope of 1% were considered. HRT equal to 6 days and incoming sewage flow rate set to 0.2 m3/d. Vertical subsurface reed had dimensions of 0.4 × 0.60 × 2 m and floor slope was equal to 1%. The control pilot (no plant) was designed exactly the same as the horizontal and vertical tests. The results were compared with coagulation-flocculation-filtration process.

The efficiency of vertical wetland in removal of TSS, COD, turbidity, phosphorus and nitrogen compounds and index bacteria were: 58.1, 62.4, 73.4, 20.41, 21.34, 40.51%; for horizontal wetland 57, 52.59, 70.3, 22.41, 18.22, 39.08%; and for conventional treatment process 85.34, 69.7, 81.55, 69.23, 73.95 and 78.2%, respectively.

Although vertical wetland was more efficient than horizontal one for most of the operation parameters, both of these wetlands were less efficient than conventional coagulation-flocculation-filtration unit of reuse process. Although operating costs of wetlands are low, these systems alone cannot be considered as a substitute for the conventional process because of their low performance for the purpose of polishing.

Recently, microplastics (MPs) have been found in the aquatic and terrestrial environments, air, and food. Other pollutants can be transported by MPs and pose a threat to the human, animal, and environment. Measurement and evaluation of microplastics can either increase knowledge about them or boost understanding of their possible harmful effects. However, no standard method has been established to measure microplastics and the measurement of microplastics has been done by various methods in different published studies. The aim of current study was to investigate different methods of measuring microplastics in water and wastewater environment and identifying the strengths and weaknesses of these methods.

The present review study was conducted during the winter 2021, by searching the papers cited in PubMed, Google Scholar, Web of Science, and Scopus databases using the keywords "Microplastic", "Water", "Drinking-water", "Wastewater", "Surface", "Bottled-water" and "Marine" and selecting articles published between 2015 and 2021 in reputable journals.

The main stages of MPs measuring in various studies included sampling and sieving, pretreatment and digestion, density separation, counting and Identification of MPs by their chemical composition.

Digestion using H2O2, density separation using NaCl, counting by stereomicroscope, and Spectroscopy using FTIR and micro-RAMAN are the most widely used methods in the studies related to detecting MPs in water and wastewater environment. However, different methods of measuring and identifying microplastics have made comparing the results of studies difficult and it seems that efforts should be made to standardize these methods.

Considering the development of industries and the importance of industrial waste production and its environmental hazards, it is important to survey the quantity and quality of waste. Therefore, the present study was conducted with the aim of properties investigation of waste produced from industrial units in Ure and Shoja Abad.

This descriptive cross-sectional study was performed in 2018. A questionnaire was used for quantitative and qualitative survey of industrial waste. For this purpose, after referring to the industrial units and completing the questionnaires, the data were analyzed to determine the status of industrial waste.

A total of 59730 and 168620 tons per year of industrial waste are respectively produced in Ure and Shoja Abad. Waste from non-metallic minerals has the highest amount of total production waste at 29460 and 151490 tons per year in Ureh and Shoja Abad, respectively.On-site recycling in the industries of Urea and Shoja Abad towns with 1212.74 and 434.91 tons per year, respectively, is the main method of waste management.

According to the results the main method of industrial waste management is on-site recycling. Non-metallic minerals are used and recycled in the production process to a greater extent than other production wastes in Urea and Shojaabad industrial plants.

Crude oil is a very complex composition containing thousands of hydrocarbons with different structure. Many compounds in crude oil, if entering in drinking, water can harmful on human health.
the effect of ozonation and powdered activated carbon separately and together for reducing the toxicity of crude oil in the water has been investigated. For toxicity test, different concentrations of water soluble fraction of crude oil in water and larvaeofrainbow trout were used. Before and after ozonatiopn and adding powder activated carbon, TOC and bioassay test was performed and the results were compared.
Findings: the ozonation at concentrations of 1 to 10 mg/l reduced the toxicity from 1.5 to 4 times. While, the use of activated carbon in concentration of 10 to 60 mg/l could decrease the toxicity in triplicate. The use of activated carbon and ozone in catalytic process can reduce the toxicity of the samples about 5 times.
the ozonation of the samples prior to activated carbon increases the adsorption and leads to better reduction of TOC and toxicity.

In a conventional method for determination of the chemical oxygen demand (COD)، organic compounds are oxidized by potassium dichromate in acidic condition and thermal digestion (150°C، 2 hr). Whereas microwave produces heat through rapid rotation of polar molecules and ionic polarization، microwave digestion was investigated for rapid measurement of COD in present study. In this experimental study، in order to compare the thermal and microwave digesters for COD determination، 243 standard samples of potassium hydrogen phthalate solution and raw wastewater and effluent samples were studied according to standard methods based on the colorimetry of reduced chromium ion. The results were analyzed by Wilcoxon test. The mean COD obtained from microwave digestion (360 Watt، 5 min) had no significant difference with the one determined by thermal reactor (150 °C، 2 hr.). Energy consumption of thermal reactor and microwave for determination of COD in each sample was determined as 736 and 30 W. hr، respectively. Therefore، the energy consumption and digestion time of thermal reactor in COD determination were about 24 fold higher than the microwave digestion. Application of microwave is preferred to the thermal reactor in terms of the time and energy consumption due to its catalytic ability in chemical oxidation.

Leachatecontaining high levels of organic pollution with ammonia، halogenatedhydrocarbons، heavy metals and inorganic salts. Among the various methods fortreating leachate، has been developed membrane processes so that a morebiological process of membrane processes is used for separation of solid -liquid. The aimof this study was to evaluate the efficiency of Membrane bioreactor efficiencyin treatment of composting plant leachate.

This study is a cross-sectional study was carried outat a laboratory scale. In this study، SBR used with 5 litercombined with hollow fiber membrane reactor about 50% porosity and operational pressureMPa 0. 02. 150 samples were analyzed andaverage concentration of COD، ammonia، phosphorus and TSS was measured in inletleachate and bioreactor effluent. Finally removal efficiency was determined.

Bioreactor efficiency removal for COD، BOD5،TSS، ammonia and phosphorus، respectively were approximately 99. 2، 99، 89. 2،87and 98٪. The paired t test، showed astatistically significant difference between the input leachate and bioreactoreffluent (p-value <0. 05). based on one-sample t test، there aresignificantly different between values of the bioreactor effluent quality and standardsvalues (p-value <0. 05).

Raw leachate pretreatment processes such as microscreening، chemical precipitation، and ammonia stripping، anaerobic reactorswould be very effective in bioreactor performance.

Listeria and in particular Listeria monocytogenes is considered a ubiquitous foodborne pathogen which can lead listeriosis in human and animals. Listeriosis can be serious and may cause meningitis، septicemia and abortion in pregnant women. Although wastewater or sludge may contaminate foods of plant origin، there are no data on occurrence of Listeria spp. in wastewater and sludge in Iran. The purpose of current investigation was to study the occurrence of Listeria spp. in various samples of wastewater and sludge in Isfahan North wastewater treatment plant. Influent، effluent، raw sludge and dried sludge samples were collected from Isfahan North municipal wastewater treatment plant. L. monocytogenes were enumerated by a three–tube most probable number (MPN) assay using enrichment Fraser broth. A total of 65 various samples from five step in 13 visits were collected. The presence of Listeria spp. also was determined using USDA procedure. Then، phenotypically identified L. monocytogenes were further confirmed by Polymerase Chain Reaction amplification. L. monocytogenes isolated from 76. 9%، 38. 5%، 84. 6%، 69. 2% and 46. 2% of influent، effluent، raw sludge، stabilized sludge and dried sludge respectively. The efficiency of wastewater treatment processes، digester tank and drying bed in removal L. monocytogenes were 69. 6%، 64. 7% and 73. 4% respectively. All phenotypically identified L. monocytogenes were further confirmed by Polymerase Chain Reaction. The results of present study have shown that Listeriaspp. and L. monocytogenes in particular، were present in wastewater treatment plant effluents and sludge at high level. The bacteria may spread on agriculture land and contaminate foods of plant origin. This may cause a risk of spreading disease to human and animals.

Moving bed biofilm reactor (MBBR) is one of the new hybrids biological systems that are used in treatment of wastewater contaminated by organic and nitrogen pollutant. In this study, the continuously operated laboratory scale Kaldnes(k1) moving bed biofilm reactors (MBBRs) was investigated. In this system, two series as Anoxic reactor (R1) and aerobic (R2) have a size 3.5 and 10 liters, respectively. This system was operated at temperature 28.5 oC, pH=7-8, DO= 1-1.5 mg/l and internal recycle ratio in continuously. All tests based on the standard methods were performed. The Anoxic and Aerobic reactors were filled to 40 and 50 %(v/v) to attach and retain biomass with k1 biofilm carriers, respectively. Statistical analysis software was SPSS and EXCEL. During operation, the average dissolved oxygen in the aerobic reactor was 1-1.5 mg/l. The average removal efficiency of soluble organic carbon (SCOD) was obtained over 95% at different load organic matter (300-2000 mg/l) in the anoxic reactor. The average removal efficiency of total nitrogen (TN) occurred in the range of 80-99.4% at different load nitrogen (25-250 mg/l) and maximum removal efficiency based on biofilm surface area occurred close 92% at loading rate of 0.127-0.181 mg-N/m2.day. The results show that nitrification rate was increased to increase loading rate of nitrogen compounds but the rate of nitrification was decreased at high loading rate. Probably this was due to an excessive accumulation of nitrite ion in the aerobic reactor. This investigation showed that the process of removal organic and nitrogen compounds in the MBBRs system under pre-denitrification without recycle sludge and external carbon source has an acceptable performance for treatment of wastewater with high load organic carbon and organic nitrogen compounds.

Contamination of drinking water sources with nitrate may cause adverse effects on human health. Due to operational and maintenance problems of physicochemical nitrate removal processes, using biological denitrification processes have been performed. The aim of this study is to evaluate nitrate removal efficiency from drinking water using autotrophic denitrifying bacteria immobilized on sulfur impregnated activated carbon in a fluidized bed bioreactor. After impregnating activated carbon by sulfur as a microorganism carriers and enrichment and inoculation of denitrifying bacteria, a laboratory-scale fluidized bed bioreactor was operated. Nitrate removal efficiency, nitrite, turbidity, hardness and TOC in the effluent were examined during the whole experiment under various conditions including constant influent nitrate concentration as 90 mg NO3--N/l corresponding to different HRT ranging from 5.53 to 1.5 hr. We found that the denitrification rates was depended on the hydraulic retention time and the nitrate removal efficiency was up to 98% and nitrite concentration was lower than 1mg/l at optimum HRT=2.4 hr respectively. Moreover, there was no difference in hardness between influent and effluent due to supplying sodium bicarbonate as carbon source for denitrifying bacteria. However pH, TOC, hardness, and turbidity of the effluent met the W.H.O guidelines for drinking water. This study demonstrated that an innovative carrier as sulfur impregnated activated carbon could be used as both the biofilm carrier and energy source for treating nitrate contaminated drinking water in the lab-scale fluidized bed bioreactor.

Cyanide is a highly toxic compound which is found normally in the wastewater of numerous industries, such as Electroplating. The release of this compound into the environment has a lot of health hazards. The Purpose of this study was to compare the electrochemical oxidation efficiency with chemical precipitation method for cyanide removal from industrial wastewater. This study was conducted experimentally in a pilot system. In this study, the optimum conditions such as pH, Fe/CN- and reaction time were investigated in the Ferrous Sulfate precipitation method for cyanide removal from wastewater of electroplating industries by the use of jar test. It also investigated the effect of pH, voltage and operation time for total cyanide removal by electrochemical oxidation method by applying a stainless steel as an anode and copper as a cathode. And finally, the efficiency of two methods was compared. In the Ferrous Sulfate Precipitation method, the optimal conditions were obtained for the removal of cyanide at (pH 6/5, and 10:1 Molar Ratio and Operation Time 60 minutes). In these conditions, the removal efficiency was 93 percent. In the electrochemical method, the optimal conditions were obtained at the voltage of 9V and pH=13 and the operation time of 90 minutes in which the average percentage removal of cyanide was about 88 with SD=2.43. The results statistically confirmed the significant relationship between cyanide removal efficiency and optimal conditions in both methods (p< 0.05). But comparison of the two methods showed that the cyanide removal efficiency in the electrochemical method was as much as the chemical precipitation method. Due to the high cyanide removal efficiency and achieving the standards for effluent disposal to the environment, it seems that ferrous Sulfate precipitation method is more useful.

crude oil is a very complex composition that contains thousands of hydrocarbons with different structure. Many compounds in crude oil if entering in drinking water can harmful to on human health. Use of bioassay method for assessment effect of purification process has considered for useful results. The effect of ozonation and powdered activated carbon separately and combination for reducing the toxicity of crude oil from water has been investigated. for toxicity test, different concentrations of water soluble fraction of crude oil added in water and larvaes of rain bow trout were used. Before and after ozonatiopn and adding powder activated carbon, TOC and bioassay test were performed. Probit test was used for analysis the result and determination of LC50. it was found Ozonation and activated carbone were effective on decreasing the toxicity and TOC.The result also shawed that the use of activated carbon for reducing the toxicity and TOC were more effective than ozonatiuon. The result showed that ozonation with 1 and 10mg/L would increase LC50 98h from 60 to 113.3 and 205.5 mg/L. At the some sample TOC concentration changed from 54.98 to 42.8 and 205.5 mg/L. LC50 96 h in the samples after add of different concentration of PAC was, 94.8, 106.6, 117.8, 138.3 and 181.5 mg/L. Ozonation of sample perior the luse of activated carbon, increasing the adsorbtion rate and resulted in more decreasing in the TOC and toxicity.

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 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. 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. 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.

Phenolic compounds have become a cause for of worldwide concern due to their persistence, toxicity and health risks. Hence, removal of these pollutants from aqueous effluents is an important practical problem. Ultrasonic technology may be used for water and wastewater treatment as an advanced oxidation process. Application of this technology, leads to the decomposition of many organic compounds during cavitation process. The degradation of 4-chlorophenol in aqueous solution under sonolysis at 45 kHz coupled with fFenton process was is investigated. The oxidation rate was influenced by many factors, such as the pH value, the amount of hydrogen peroxide, catalyst (FeSO4) and initial p-chlorophenol concentration. The experimental results showed that the decomposition of p-chlorophenol was affected by the various reaction conditions. The optimum conditions obtained for the best degradation rate were pH=3, H2O2 concentration of 0.05 mol/L and 0.025 mmol/L for catalyst, respectively. Also it was observed that the degradation of p-chlorophenol depended on its initial concentration.

Crude oil is very complex composition with harmful effect in human health, such as carcinogenesis and blood dyscrasia. Because of the entry of relatively high volume of these compounds in aquatic environments, effective controlling is very important. The aim of this study was to investigate the effect of powdered activated carbon (PAC) for reducing the toxicity of crude oil in water. Water soluble fraction standard samples were prepared with one part crude oil in 9 part water. For toxicity test, different concentrations of crude oil water soluble fraction in water and larvae of rainbow trout were used. Before and after the addition of 10, 20, 40 and 60 mg/l powdered activated carbon, TOC and bioassay tests were performed. LC50 and evaluation of results was done with probit statistic program. LC50 for samples 24, 48, 96 hrsafter addion of different concentration of PAC were 94.8, 106.6, 117.8, 138.3 and 181.5 mg/l. Values of TOC for these samples was 44.81, 43.88, 38.16, 36.62 and 35.14 mg/l. The use of activated carbon reduced toxicity and TOC. With increase in the concentration of activated carbon, toxicity was decreased, but intensity of TOC removal wasn’t similar to toxicity removal. Using of powdered activated carbon for treatment, in case of accidents and entering crude oil in drinking water supplies, can be considered.

This study was carried out to evaluate the secondary effluent disinfection of the Isfahan north municipal wastewater treatment plant using filtration and UV technology in current operational condition. The combined system was used in series in pilot scale including: Pressure Sand Filter + Low Pressure (LP) + Medium Pressure (MP) UV Lamps. The UV dose varied according to the initial intensity of lamp, flow rate and influent transmittance. Total coliform (TC), fecal coliform (FC) and fecal streptococcus (FS) were analyzed as microbiological parameters in all effluent samples. TSS, BOD5, COD, VSS, pH and transmittance (UVT percentage) were tested as physicochemical parameters, before and after the units. Results showed that the filtration with loading of 1050 lit/m2.hr, followed by MP lamp with dose of 230 mW.s/cm2 is an effective alternative to reduce the TC/FC and FS in the secondary effluent. The combined disinfection processes that were used in this study, could be met the standards of 1000 TC, and 400FC/100ml for effluent discharge to receiving waters or restricted reuses in the agriculture. This process can also inactivate the FS down to 6-log.Using low-pressure lamps due to low dose radiation for disinfection is not cost-effective. In this study, parasite egg counts due to lack of access to accurate identification techniques for alive cyst detection was not examined.

There are many varieties of compounds in chemical and petrochemical wastewater. One of the important members of the Chlorophenols (CPs) family is ρ-chlorophenol. This pollutant is introduced into the environment through various human activities such as waste incineration, uncontrolled use of wood preservatives, pesticides, fungicides and herbicides, as well as via bleaching the pulp with chlorine, chlorination of drinking water and wastewater.Experiments with microwave irradiation were carried out in a modified domestic microwave oven with the cooling system (2450MHz, SAMSUNG Co.). The oxidation rate was influenced by many factors, such as the pH value, the amount of hydrogen peroxide, the irradiation time, the initial concentration of organic material and the microwave power.The result showed that the optimum conditions obtained for the best degradation rate was pH=10.5, the H2O2 concentration of about 0.1 mol/L and the microwave irradiation power of about 600W for the microwave/H2O2 system at constant ρ-chlorophenol concentration. The degradation of ρ-chlorophenol by different types of oxidation processes were followed by the first order rate decay kinetics. The energy consumption for UV/H2O2 in degradation of p-Chlorophenol (93%) and the reaction time of 180 min was 17460 KWh/kg p-Chlorophenol removing.

Crude oil is a very complex composition with harmful effects in human health such as carcinogenesis and blood effects. Using the bioassay method to assess the effect of purification process produces useful results. In this study the effect of ozonation to reduce the toxicity of crude oil in the water is investigated.

Standard sample of the water soluble fraction were prepared with one part of crude oil and 9 part of water. For toxicity assessment, different concentrations of water soluble fraction of crude oil and larvae of rainbow trout were used. Before and after ozonation, TOC and the bioassay tests were performed.

Ozonation is effective in reducing the toxicity of the crude oil in drinking water. By increasing the time of bioassay experiment, the toxicity is increased too. LC 50%, 98 hours of the sample TOC was 60 and 54.98 mg/l before the ozonation process and after that in 1 and 10 mg/l, LC 50%, 98 hours was increased to 113.3 and 205.5 mg/l and the TOC reached to 42.8 and 205.5 mg/l.

Increasing the ozone doses to reduce the toxicity was highly effective, but intensity of TOC removal was not the same as the toxicity removal. In order to investigate the effectiveness of one treatment process to remove special pollutants, using bioassay test could produce useful and valuable results.

The Biological Solids produced during wastewater treatment processes are called sludge. As sludge contains various sickening microorganisms such as pathogens, organic and inorganic substances and has adverse effects on human and environment, therefore it should be treated and processed entirely prior to disposal and then disposed in line to the environmental regulations. Thermal treatment is one of the sludge treatment methods. Among these, microwave as one of the methods, could have an important role in sludge treatment. This study investigated the Microwave application to reduce volume and the final stabilization in primary and secondary sludge produced by south Isfahan WWTP in comparison with conventional laboratory electrical furnace. A batch system was set up to compare the microwave oven and electrical furnace in converting the primary and secondary sludge in south Isfahan WWTP (as a sample only and with adsorbent addition). The effects of relevant parameters tested were included the contact times between 1 and 10 minutes for microwave oven and 240 and 300 minutes for the electrical furnace, heating and the adsorbent dosage in the range of 5 to 30(w/w%) affect of the sludge mass temperature production, weight reduction percentage and total and volatile reduction percentage, coliform and HPC decrease. The study relieved that by increasing the radiation time, the microwave oven performance on the sludge sample increased significantly. In the samples with different percentages of adsorbent addition, the mass temperature increased to 600°c in microwave oven, however, in the samples treated in electrical furnace or with no adsorbent addition(in the microwave oven) no significant effect was observed on the temperature. Overall the study findings on the microbiological characteristics also indicated that the sludge samples contain different percentages of adsorbent addition. The removal efficiency of coliforms and HPC increased up to 100% the microwave oven but in the samples with no adsorbent addition it was able to reduce them to 4.5 and 5 log respectively. Overall data achieved from the study revealed that, if the sludge samples without adsorbent additives are placed under microwave radiation exposures in different times scales, they only are dried lose their humidity, but with different adsorbent addition dosage, in addition to drying, due to excessive temperature increasing in the sample mass, Pyrolysis process may occur and then the sludge samples are stabilized during digestion.

Backgrounds and Today, due to health, environmental and economical problems, of chlorine application, UV radiation is better option than chlorine for disinfection of effluent. The aim of this study was disinfection of secondary effluent with UV radiation. Two types of UV disinfection system including low pressure (LP) and medium pressure (MP) was used to disinfection of Isfahan North Wastewater Treatment Plant (INWWTP) effluent without pretreatment. Single and combined lamps were operated to evaluate the removal of total and fecal coliforms (TC and FC), and fecal streptococcus (FS). TSS, iron, hardness, UV absorption and transmittance were analyzed in order to observe the fouling of the quartz sleeves. After using LP lamp with dose of 161 mws/cm2, TC and FC content was declined to standard level (1000 TC, and 400 FC/100ml). In addition, disinfection with MP lamp was led to FS content of 400 MPN/100 mL. Combination of LP and MP, with dose of 460 mws/cm2 could be met the environmental requirements of TC & FC, and the FS count was reached to 400 MPN/100 mL with dose of 237 mws/cm2. Maximum photo-reactivation percentage of coliforms after LP and MP lamps were appeared 15 and 3 percent respectively, while it was not observed for FS. High fluctuation in secondary effluent quality of INWWTP mainly TSS concentration was caused to decline of the UVT value. Therefore, disinfection of effluent by LP, MP and even combined both systems are not applicable in conventional UV dose. Hence, using advanced process unit before UV disinfection system is necessary for removal of TSS.

In recent years, chitosan and Moringa oleifera Coagulant Protein a natural coagulant were used in order to reduce the problems occure from chemical coagulants. This investigation was done to determine effectiveness of Moringa Oleifera Coagulant Protein and Chitosan as natural coagulant aids in removal of colloidal particles and bacteria from turbid waters. In this interventional- quasi experimental study, the experiments were run by using synthetic water having low(10-20NTU), medium(100-120NTU) and high (200-220NTU) initial turbidities. In order to determine optimum pH and dosage of coagulant and coagulant aids, a conventional jar test apparatus was employed. Turbidity reading were carried out using a Hach model 2100P Turbidimeter. The samples were taken from the top four inch of the suspension for turbidity and bacteria removal measurement. Optimum dose of alum for waters with three different initial turbidities were 20, 40, and 20 mg/l, respectively. Optimum pH was between 7-7.5. Moringa oleifera Coagulant Protein and chitosan were reduced the required dosage of alum from 12.5% to 62.5% and from 50% to 87.5%, respectively, in different turbidities and residual aluminum was reduced to standard limit (0.2mg/l). The bacteria removal efficiency were from 90% to 99.9999%. It was found when samples were stored during 24 hours regrowth of E.coli was not observed. This study showed that natural coagulant aids can reduce the turbidity to below 5NTU without filtration in optimum condition.

Although Iran is known as an iodine sufficient area, congenital hypothyroidism (CH) is prevalent. Because iodine excess can contribute to hypothyroidism, we evaluated the role of iodine excess and ID in the etiology of CH. Methods and Materials: In a cross sectional study UICs (Urine Iodine Concentration) in newborns with CH as well as UIC and MIC (Milk Iodine Concentration) of their mothers were compared with a control group. After acid digestion of urine samples milk samples, iodine concentrations were determined by the Sandell-Kolthoff method. Chi-square and Wilcoxon, and Pearson correlation tests were used for statistical analysis. A P value less than 0.05 was considered statistically significant. The median of MIC of CH (n=68) and healthy subjects (n=179) was different (210 vs. 170 µg/L respectively, P<0.05). However the median of UIC in neonates and those of mother's of CH and healthy subjects were not different statistically (305 vs. 300µg/L and 150 vs.130µg/L respectively, P>0.05) 71.2% and 46.7% of mothers of hypothyroid and healthy subjects had MICs above 180 µg/l (iodine excess) respectively (p=0.002). Based on the higher levels of MIC in mothers of CH neonates, iodine excess could be a possible risk factor for CH. Since however comparison of UIC between the control and neonate groups showed no differences, further investigations are needed to facilitate deeper insight into and clarification of the etiology of CH.

Flotation involves separation of solids from the water phase by attaching the solids to fine air bubbles to decrease the density of the particles. Flotation including of tree type 1. Vacuum flotation, 2. Dispersed air flotation and 3.dissolved air flotation. In this research used from dissolved air flotation. Various industries produce many goods and marchandias and affects our environment. Vegetable oil manufacturing is one of these industries. The main pollutants in the east of this industry are chemical oxygen demand (COD), biochemical oxygen demand (BOD) and Oil. The aim of this assay is to study the reduction of pollution of vegetable oil manufacturing wastewater with “DAF” system. At first phase of these examinations, the optimum dosage of the coagulants was determined. The coagulants that used in this study were Alum and Ferric Chloride. The second phase was flotation. In this series of examinations, oil, COD, total solid, volatile solid, fixed solid and suspended solid measured in raw wastewater and the effluent of the DAF pilot Optimum value of “pH” for Alum and Chloride ferric obtained 7.5 and 5.5 respectively. And optimum dosage for these obtained 30and 32 mg/l respectively in this search. Mean moval for the parameters of oil, COD, total solid, volatile solid, fixed solid and suspended solid obtained 75.85%, 78.27%, 77.32%, 82.47%, 73.52% and 85.53% respectively. During pressure rising from 3 to 4 and 5atm removing rate of COD, total solid, volatile solid, fixed solid parameters reduced but oil and suspended solid have increase. In addition to, following increase of flotation time up to 120s all of the measured parameters have increase in removing rate. Optimum A/S for removal of COD, total solid, volatile solid, fixed solid parameters obtained 0.001 and for oil and suspended solid obtained 0.0015