یوسف پور عشق

Water resources are often exposed to pollutants related to urban waste disposal. This study aimed to determine the quality of water sources around the landfill of Langrod City in 2021.

This cross-sectional study selected two springs upstream, two water sources (well and spring) downstream of the landfill site, and a river (with two sampling stations) near the landfill site as the studied water sources. Sampling and analysis of physical (temperature, turbidity and TSS), chemical (pH, EC, TDS, BOD5, COD, nitrate, sulfate and heavy metals) and microbial (coliform and E.coli) parameters of water quality and soil samples of the region with Standard methods were performed. The data were analyzed by comparison with Iranian standards, Schuler and Wilcox indices.

In all water samples, the turbidity was more than the desired level, and the concentration of all chemical parameters was lower than MCL in the Iranian standard for drinking and irrigation. In the downstream well of the landfill, the total concentration of nitrite and nitrate measured compared to the recommended values in drinking water was almost four times the Iranian standard. The number of coliform and E. coli in all water sources was higher than the permissible limit of Iran's standard for drinking. The quality of all water samples, based on the Schuler diagram (drinking), was acceptable to good, and according to the Wilcox index, except for the downstream river of the landfill, they were in the medium salty category and were relatively suitable for agriculture.

The quality of water sources upstream and downstream of the Langrod urban waste landfill site was similar, and the water quality of the river downstream of the landfill was high salty and suitable for agriculture with the necessary considerations (drainage).

 Radioactive compounds in water and wastewater have raised global concerns. Numerous epidemiological studies have shown that these substances can endanger the health of humans and animals. These contaminants must be removed before entering the natural cycle due to their carcinogenic properties. This study investigated the processes of removing radioactive compounds from water and wastewater.

 For this purpose, related articles were selected from Scopus, PubMed, and Web of Science databases. Overall, 89 articles were retrieved, and ultimately 11 articles were reviewed after removing duplicates and deleting unrelated studies. Experimental conditions, including pH, temperature, initial concentration, adsorbent dose, ionic strength, and contact time, as well as adsorbent regeneration and adsorption/recovery capacity, were extracted from these studies. 

 Almost all adsorption experiments were performed at room temperature and showed that higher temperature leads to higher adsorption rates. More than 45% of studies determined the optimum pH at the 6-7 range. In addition, increasing the initial concentration improves the adsorption capacity while reducing metal ion recovery. Most articles (44%) used of Langmuir equation to model isotherm studies. In addition, about 41% of them described the adsorption kinetics with a pseudo-second-order model and suggested chemical adsorption as a velocity-limiting step. 

 As discussed in this review, decontamination of such wastewater is much more challenging than handling conventional industrial and municipal wastewater. However, further studies concerning well-designed large-scale studies are needed to strengthen the evidence.

The presence of natural organic matter in water sources creates various problems, especially in common water treatment process. These compounds cause unfavorable taste and odor in water and are among the most important precursors of water disinfection by-products. This study was carried out to evaluate the efficiency of activated carbon (AC) and activated carbon modified with ZnO nanoparticles (AC-ZnO) in removal of humic acid (HA) from aqueous solutions.

In the present experimental study, the removal of HA with AC or AC-ZnO was discontinuously studied as a function of pH, contact time, HA concentration, and absorbent dose. The structure of absorbents and their morphology were investigated by FTIR, SEM, XRD and pHpzc techniques. The HA was measured using spectrophotometer at the wavelength of 245 nm. Absorption isotherm was determined by using Langmuir and Froundlich models and absorption kinetics by pseudo-first and pseudo second-order models.

The efficiency of removing HA had a direct relationship with absorbent dose and inverse relationship with pH and HA concentrations. The optimal removal rate of HA for 1.6 g/L dose of AC or AC-ZnO were reached to 82.44 % and 96/26%, respectively, in HA concentration of 50 mg/L and contact time of 40 minutes

The removal rate was considerably higher for AC-ZnO than AC, which indicates the effective role of nanoparticulate stabilization on activated carbon. As a result, the method of nanoparticulate stabilization on activated carbon can provide an effective and very efficient adsorbent and appropriate alternative to remove humic acid from aqueous media.

Ethidium bromide is known as a Mutagenic substance that due to some of its characteristics including accumulative property in organism bodies, can cause major environmental problems. In this research, we studied the effect of activated persulfate by electrochemical method in removal of ethidium bromide in laboratory conditions.
In this experimental study, which was conducted in a laboratory pilot, used from a discontinued reactor with one liter capacity that equipped with four electrodes of iron as a monopolar connection? Entrance voltage (Amper), initial concentration of persulfate, pH, reaction time and initial concentration of Ethidium bromide was investigated. The remaining concentrations of Ethidium bromide was determined by using spectrophotometry at a wavelength of 480 nm.
The results of this study showed that the initial pH, entrance voltage and the initial concentrations of persulfate have a significant effect on the removal of pollutants, also the maximum removal rate occurred in acidic pH. By increasing the concentration of persulfate and the entrance voltage, the efficiency of the process increased and by increasing the initial concentration of Ethidium bromide, the efficiency of the process decreased. So that in appropriate conditions obtained from the experiment, 93.2% of the pollutant was removed in40 minutes and 100% in 60 minutes. Also removal efficiency for COD at optimal time was 72 %.
The results showed that by using activated persulfate in electrochemical process with iron electrodes can be an appropriate method to remove the pollutants in refineries and aqueous solutions.

Surfactants can be found in soaps, detergents, pharmaceutical products, personal care products, as well as in leather industries. In this study, adsorption of Sodium Dodecyl Sulfate (SDS) on magnetic multi-walled carbon nanotubes in the aqueous solutions was investigated.
Surfactant concentration, adsorbent dosage, and pH values were considered as variables. Residual surfactant was measured using methylene blue method and adsorbent characteristic was determined by X-Ray diffraction and Fourier transform infrared spectroscopic analysis. Adsorption capacity, adsorption isotherm, and kinetic reaction were also investigated.
Adsorption investigations demonstrated that the increase in initial SDS concentration or pH values, led to the decrease in SDS adsorption. Conversely, the same result was achieved by decreasing adsorbent dosage. After 120 min SDS adsorption became stable. By increasing in SDS concentration from 15 to 150 mg/L, adsorption capacity improved from 8 to 61 mg/g. Isotherm and kinetic data demonstrated that experimental data pursued Langmuir isotherm (R2=0.993) and pseudo-second order equation (R2=0.992).
Magnetic multiwall carbon nanotubes can be used as an effective and useful sorbent for SDS removal due to several advantages including: high adsorption capacity, relatively low equilibrium time, and easy separation of magnetic multiwall carbon nanotubes from aqueous solutions.

Methods of mineral adsorbents recognition and surveying methods of making new adsorbent are essential due to importance of applying effective and inexpensive methods for wastewater treatment. Zeolite and Kaolin are among the conventional adsorbents which have been used for removing many pollutants. In this study, synthesis of zeolite materials by hydrothermal transformation of natural Iranian kaolin was investigated at 850ºC for 2 hr.
In this study, physical properties of kaolin was determined using different experiments such as laser particle size analyzer (PSA) and chemical properties was studied by SEM, XRD and FTIR methods. Synthesis of Zeolite materials by hydrothermal transformation of natural Iranian kaolin in NaOH solutions was investigated at 850ºC for 2 hr.
The experiment results showed; kaolin density = 2.608 gr/Cm3, particle size = 0.37-52.76 µm, specific surface area (BET) = 9.17± 0.0748 m2/g and pHpzc = ~8.5. SEM results showed flak shape for kaolin particle. X-ray diffraction illustrated quartz as a major phase of the kaolin. The presence of AL and Si functional groups was proved by FTIR. SEM results demonstrated raised surface and irregular shape for the zeolite particles. XRD and FTIR results confirmed the crystalline structure of quartz and presence of SiO2 and AL3 and Si-AL functional groups, respectively
The results revealed that application of hydrothermal method using calcinations process in the presence of NaOH is an appropriate and inexpensive method for zeolite production and this synthetic zeolite has the highest similarity to Clinoptilolite.

Electro-Ozonation process (EOP) has a good potential for the removal of persistent organic pollutants. This process is a combination of ozonation process and electricity for producing hydroxyl radical and removal of pollutants. The purpose of this study was to evaluate the EOP for SDBS degradation in aqueous media. In this experimental study, a semi-batch reactor with four graphite electrodes of 120 cm2 area was used. The effects of pH (3-11), the inlet of ozone (6-30 mM / s), current density (16-85 mA/cm2), the initial concentration of SDBS (0.02-0.3 mM/L) and radical scavenger dose (0.2 mM/L) were studied.SDBS concentration measured by spectrophotometer (DR5000) by instructions provided in the standard method book. The results indicate the high efficiency of this process in the removal of SBDS and COD. In optimum conditions of pH = 3, current 85 mA/cm2, ozone flow rate 30 mM/s and initial SDBS concentration 0.02 mM/L, more than 99% removal was observed in 50 min. By changing the parameters of the optimum conditions, the process performance was decreased. High efficiency of COD removal in this process was obtained in 80 min. Influence of TBA in solution was the efficiency decrease of process to 80 %. Electro-ozonation process as an advanced oxidation process can reduce organic pollution industry and can be considered as an environmentally friendly process.

Electrochemical processes have been applied effectively to remove organic compounds from aqueous solutions. In this work، the efficiencies of Electro Fenton (EF) process and Electrocoagulation (EC) using iron electrodes were investigated for removal of Acid Black 1. This experimental study was performed in a batch reactor and the effects of parameters such as pH، time، voltage، H2O2 and dye concentrations، and COD removal were investigated. In Electro Fenton process H2O2 was chemically added to the reactor while iron anode electrode was used as a ferrous ion source. The results showed that pH، voltage and H2O2 concentration were the main parameters in EF process. The optimum conditions in EF process were obtained at pH 3، H2O2concentration of 100 mg/l and 20 V. With increasing pH from 3 to 11 and voltage from 20 to 40 V the removal efficiency decreased، however، in the EC process the maximum efficiency was obtained at pH 7. Electro Fenton and Electrocoagulation using iron electrodes are suitable processes for dye degradation and treatment of colored wastewater.

Usually, to produce radical sulfate, persulfate anions can be activated by heat, UV light and transition metals such as iron ions. The purpose of this study was investigation of performance of persulfate activated with iron produced by electrical method using iron anode electrode in degradation of Acid Blue 113 from aqueous solutions. In this study, a lab-scale electrochemical batch reactor equipped with four iron electrodes and a DC power supply was used for removing of Acid Blue 113. The effect of operating parameters such as initial pH, voltage, persulfate and initial Acid Blue 113 concentration were evaluated. Also, the amount of pH changes during the process, the synergistic effect of processes in the system and Acid Blue 113 UV-Vis spectrum analysis in optimal conditions was investigated. The results showed, initial pH of solution, initial concentration persulfate and applied voltage has a significant effect on dye removal. Dye removal efficiency was higher in acidic condition and decreased with increasing pH, So that, after 2 min of reaction at pH 3, voltage 10 V and 150 mg/L of persulfate, 98% of the dye was removed, at pH 5, 7, 9 and 11, after 2 min of reaction and in the same condition the dye removal efficiency was, 66, 0, 0 and 13.5%, respectively. With increasing voltage from 1 to 10 V, increased the dye removal efficiency. S2O82- at the end of 20 min of reaction, removed 17% of dye, at the same condition, electrochemical process with iron electrode had only 31% efficiency, but, the combination of these two processes could remove 99.8% of dye. The use of S2O82- anions in an electrochemical reactor with iron electrodes can be increase the efficiency of process. Therefore, using this process can be promising process to industrial wastewater treatment.

Heavy metals in industrial wastewater especially chromium (VI) are considered as the main environmental pollutants. Electrochemical cell made of plexiglass with a volume of 1.95 lit was used. Iron and graphite electrodes, electricity conductor, each with dimensions of 0.1×3×10 cm (width×length×height) were designed and built. Tests were carried out in various conditions of pH, concentrations of input chromium (VI), different amounts of electrolytes, electric currents and retention times. Measurement of samples was performed using of diphenylhydrazine method. Maximum removal efficiency for iron and carbon electrodes at about 99.8% and 88.3% was observed, respectively. The lowest among of Cr+3 in efficiency wastewater of system was recorded about 0.05 mg/l for Fe electrode. The results showed that the operation of the electrochemical cell, efficiency removal of Cr (VI) by iron electrode in the same process conditions is more than carbon electrode. Generally, despite in this method removal efficiency of hexavalent chromium from synthetic wastewater is acceptable however consume a lot of electrical energy. Thus, electrochemical method is usable for the removal of heavy metals in industrial scale.

Cyanide ion is one of the most dangerous compounds for the man. Electrocoagulation process with high efficiency to removing pollutants, than researchers considered a effective process. The aim of this study was to determine the efficiency of electrocoagulation process by aluminum electrodes in cyanide removal from synthetic wastewater using magnesium oxide as a coagulantaid. Mehods: In this study, a reactor with four aluminum electrodes with dimensions 200 × 20 × 2 mm use of 1 Liter of useful volume of electricity generating device for the removal of cyanide was used. Effect of parameters such as pH(3-9), voltage (10-30 V), the initial concentration of cyanide(50-500 ppm) and different concentrations of magnesium oxide particles (0.1 to 1 mg l) as coagulant aid in the process were investigated. The results show that the efficiency of EC process at pH 5, voltage of 30 V and an initial concentration of cyanide, 50 mg/lit in 45 minutes, was 80 percent. process will Efficiency by adding coagulant aid. In optimal amounts of coagulant aid (0.1 mg/lit) in electrocoagulation process on the removal of the cyanide 90% was achieved. Electrocoagulation process is suitable process for the removal of cyanide. Also, Magnesium Oxide as a coagulant aid in this process was good and increase process efficiency.

This study aimed at evaluating the water quality of thermal springs of Nir، Ardabil province، with emphasize on S. aureus bacteria، as one of the organisms that involved in skin and eye infection، in the first half of 2011. In this study، 45 samples were collected from all thermal springs of Nir from May to September. The levels of free residual chlorine، temperature، pH، turbidity، H2S، ORP، DO، and EC were measured in situ by portable devices. Total coliform، fecal coliform، Staphylococcus aurous، fecal streptococci and HPC were determined according to Standard methods for examination of water and wastewater. The results showed that the highest levels of contamination to total coliform، fecal coliform، Staphylococcus aurous، and HPC were occurred in July. The lowest contamination to fecal streptococcus (maximum 11 MPN/100) was observed in August. Significant difference was observed between the months of sampling and S. aureus contamination (p<0. 001). On the other hand، S. aureus contamination showed significant inverse correlation with water temperature and directly correlated with turbidity (p<0. 05). There has been no statistically significant correlation between bacterial contamination and pH and H2S. The results showed that Staphylococcus aureus contamination level in 86. 67% of samples were higher than the standard limits (MPN/100<50)، which is a significant alarm for occurrence of skin diseases and probable infections to swimmers.

The determination of influent and effluent water quality of water treatment plants is important to increase standards of water quality for users. Parsabad city situated in north of Ardabil province and is the biggest city of province Ardabil. So, this study was accomplished due to lack of substantial studies for Parsabad water treatment plant. In the study, some of the important parameters of water was investigated for 7 years and was presented solutions for improvement treatment plant performance. This study was accomplished since 1384 to 1390 and four parameters total dissolved solids, turbidity, phosphate and calcium with 192 samples (96 samples collected from treatment plant influent and 96 samples collected from effluent) were analyzed according to standard methods for the examination of water and wastewater. Maximum removal performance of turbidity, total dissolved solids, phosphate and calcium were 99.8, 6.1, 92.67 and 28.45 respectively, during 7 years operation of treatment plant. The results of this study showed that Parsabad water treatment plant with having a rapid sand filter, enable to remove turbidity up 85% when maximum turbidity at treatment plant influent was 700 NTU. But, significant difference statistically was not observed between influent and effluent samples of total dissolved solids and calcium (Pvalue˃0.05) and removal performance were trivial for total dissolved solids and calcium. Also, this treatment plant has not good performance (mean %38) for phosphate removal.

Cyanide is a very hazardous compound that enters into the environment by different industries. In this study performance of Electrofenton process (EFP) for elimination of cyanide from aquatic environment in presence of humic Acid as an interfering compound was evaluated. In this experimental study، at every step of experiment، 1000 mL of cyanide solution with known concentrations was added to a reactor. The effects of selected parameters such as pH (3-10)، reaction time (5-20 min) cyanide concentrations (100–1000 mg/l)، voltage (10-30V)، hydrogen peroxide concentrations (5-50 ml/lit)، and humic acid levels (25-100 mg/L) on cyanide removal were investigated. The results showed that efficiency of EFT process decreased with increasing pH، concentrations of cyanide and humic acid and increased with increasing voltage and hydrogen peroxide levels. The efficiency of 72% was achieved for EFP process in optimum conditions of pH = 3، initial concentration of cyanide = 100 mg/lit، hydrogen peroxide level = 25 ml/lit، voltage = 30V، and humic acid concentration = 25 mg/lit. In the same conditions، however، EFP efficiency was 96% in the absence of humic acid The overall results show that this process has high ability on removal of cyanide. This process was influenced by the parameters studied and the removal efficiency was varied with variation of each parameter.

Monitoring and quality control of water resources are important tools to manage and protect these valuable resources. Hiroo River is the principal source of water supplies for Khalkhal and Kosar cities. The purpose of this work was to investigate water quality of Hiroo River by NSFWQI and WILCOX indices. In this descriptive cross-sectional study; pH، DO، BOD، TS، NO3، PO4، turbidity، temperature، fecal coliform، EC، Na، K، Ca، and Mg were determined. NSFWQI and WILCOX indices were applied. Data were analyzed by determining the above mentioned quality indices. In the optimum situation، NSFWQI was related to S1 with the value of 74 in February 2009 indicating good water quality. Minimum value of 53 was determined for NSFWQI at S3 in August 2009 representing medium water quality. Water quality was good in upstream (S1) due to lack of contamination sources، however، discharging wastewater of Khalkhal and Givi cities to the river decreased water quality gradually in downstream (S2 and S4). Average of data obtained indicates that all the monitoring stations fall in C (medium) category based on NSFWQI classification.

Pollution of water resources to organic matters and their associated problems including taste، odor، and formation of disinfectant by-products require evaluating removal methods for these materials from drinking water. This study aimed to evaluate performance of organic matter removal from water using deaerating system. A PVC pilot deaerator tower (diameter=15، height=140 cm) was designed، constructed، and used for this study. The system was loaded in flow rates of 0. 6، 0. 8، 1، 1. 2، and 1. 5 l/min. Absorption of samples were measured at wavelength of 253. 7 nm and COD was determined for all samples. COD levels and absorption rates of samples decreased with time for flow rates of. 6، 0. 8، 1، and 1. 2 l/min. However، absorption rates and CODs increased with increasing flow rate (except for flow rate of 1. 5 l/min). Deaeration tower system has capability to remove organic matters from water and the highest efficiency was observed at low flow rates. In addition، significant relationships (R2>0. 95) was observed between COD and absorption rates (except for flow rate of 1. 5 l/min)، and that COD may be measured through determination of absorption rate at UV wave length.

The effluent of textile industries is high dyefully and this is one of most problems for environmental health engineers. Two Azo dyes biosorption، direct black 19 and direct red 23، on Cystoseira indica، an invasive macroalga in Iran، has been investigated using visible absorption spectroscopy. Pre-treatment and chemical cross-linking with CaCl2، have been conducted in order to improve the stability as well as the biosorption capacity of the algal biomass. All measurements were conducted by UV-Visible Spectrophotometer. The effects of operating parameters such as contact time، pH، initial dye concentration and amount of biosorbent on the dye removal efficiency were investigated. The biosorption has been described in terms of isotherm and kinetic models; from the maximum adsorption capacity values، an estimation of the algal specific surface area was made. It has been found that biosorption kinetics can be described according to the pseudo second order model and biosorption equilibrated for 120 min (89. 3% of direct red 23 and 69. 02% of direct black 19 removed). Maximum biosorption found at pH 5 (2. 4mg/g). It also observed increasing initial dye concentration and decreasing biomass dosage would reduce dye removal. Isotherm studies also revealed the dye biosorption on algal biomass followed from Freundlich model. Biosorption of selected Azo dyes onto algal biomass، Cystoseira indica was fast and more dye is eliminated in the first hour. So، by determining the optimum conditions of contact time، pH، initial dye concentration and biosorbent dosage، Cystoseira indica can be used as an inexpensive sorbent for removal of Azo dyes from aqueous solutions.

Pollution of groundwater and surface waters to nitrate is an environmental problem in many parts of the world including Iran. It might cause diseases such as methemoglobinemia, lymphatic system, and blood cancer. Therefore, nitrate removal from water resources is necessary. Since application of nanomaterials in treatment of the environment pollutants has become an interesting method, the objective of this study was application of ZnO nanoparticles under UV radiation to remove nitrate from aqueous solution. Three nitrate concentrations of 50, 100 and 150 mg/l were considered for present study. In order to determine the optimum level of ZnO nanoparticles on nitrate removal, concentrations of 0.1, 0.4, and 0.8 g/l were used. PH ranges of 5-9 were studied. Also, the effect of UV irradiation was investigated. In this study, the effects of exposure time, nitrate concentration, ZnO nanoparticle dose, and pH were investigated. The results showed that nitrate removal decreases with increasing initial nitrate concentration. Also, nitrate removal efficiency increased from 75.7% at 0.1 g/l to 91.2% at 0.8 g/l 0f photo-catalyst. Maximum reduction efficiency was observed in neutral pH. For UV application, maximum performance of 27% was observed at pH=9. Application of UV irradiation solely did not effectively removed nitrate from aqueous solution, however, efficiency of combination of ZnO/UV process was appropriate for nitrate removal.

Considering the effect of Pseudomonas aeroginosa on public health as one of the most important microorganisms in swimming pools, this study was conducted to assess the possibility of contamination of hot spring pools with this organism in Ardabil province. In this study, 195 specimens were investigated from all public hot spring pools of Ardabil province during April to September 2011 when the number of swimmers reaches its peak. Standard method was used to investigate the presence or absence of P. aeroginosa in the valume of 100 ml collected samples. The rates of contamination with P. aeruginosa at different months were as follows: April 17.5%, May 22.5%, June 22.5%, July 25% and August 20%. There was no statistically significant difference for P. aeroginosa contamination within the months. However, a statistically significant difference was considered for P. aeroginosa among all locations (p <0.05). Totally, 22.9% of specimens revealed P. aeroginosa which is alarming. So, it is suggested that monitoring and disinfection the public hot spring pools should be considered more seriously. It is also necessary to limit the number swimmers in public hot spring pools to reduce burden of contamination.

In the nuclear industry، aerosols play an important role on emission and dispersion of pollutants. Nuclear reactors are the principal sources for pollution in fuel cycle and emit different radioisotopes into the environment. The radioactivity and size distribution of aerosols were measured using Anderson cascade Impactor (ACI) at three workstations in Tehran Research Reactor safety enclosure. Mass concentration and distribution of airborne particles in the chamber environment were determined using ACI. In order to identify radionuclides present in airborne particles of chamber fiber filters were used. Element identification and mass concentrations were performed using ICP-MS. To identify radionuclide type and determine their radioactivity in suspended particles، -ray spectrometry and liquid Scintillation spectrometer were used، respectively. Pb212، Pb214، Be212، Be214، Tl208، Ac228 and k40 radionuclides were determined by gamma spectrometry. Maximum mass was related to fine particle of 0 to 0. 4 µm. The greatest portion of alpha and beta particle were adsorbed on aerosols with the aerodynamic diameter of less than 0. 4µm. Majority of radioactivity was related to the particles in storage and nucleation areas (fine particles). The origin of these particles may be coagulation of mode particles «nucleation» and concentration growth in the particle size of studied.

The contamination of water by organic pollutant viz. phenolic compounds is a worldwide environmental problem due to their highly toxic nature. Biosorption has been attracted as a new technique to remove these contaminants from water and wastewater. The purpose of this study was to introduce an indigenous and inexpensive adsorbent، brown algae، for removal of phenolic compounds Phenol، 2-chlorophenol and 4-chlorophenol adsorption on Cystoseira indica has been investigated using HPLC، High Performance Liquid Chromatography. Pre-treatment، protonation and chemical cross-linking with CaCl2، have been done in order to improve the stability as well as the adsorption capacity of the algal biomass. The effect of various parameters like adsorbent dose، pH، contact time and initial phenolic concentration were studied for their optimization. The equilibrium binding has been described in terms of Langmuir or Freundlich isotherms and kinetic models. Data indicated that biosorption process was equilibrated for 2 hours and then desorption surpassed absorption process. Phenol showed lower elimination rate than 4-chlorophenol and 2-chlorophenol and 2-chlorophenol had most elimination. The rate of adsorption of phenol، 2-chlorophenol and 4-chlorophenol were found to be maximum at neutral pH. Equilibrium adsorption data for phenol، 2-chlorophenol and 4-chlorophenol were fitted by using Langmuir، Freundlich and Freundlich adsorption isotherms model respectively. Also it has been found that adsorption kinetics can be described according to the Pseudo-second order model، from which the R2 and the normalized standard deviation (NSD)، were determined. The results showed reasonable adsorption capacity of Cystoseira indica brown algae and can be used as a native alternative to phenolic compounds removal from aqueous environments.

Chemical and microbial quality are the most important characteristics associated with wastewater reuse for agricultural purposes. The aim of this study was determination of efficiency of Ghasr-e-Shirin (constructed wetland) and Kermanshah wastewater treatment plants (conventional activated sludge) to remove protozoan cysts and parasitic eggs in order to reuse in agricultural irrigation. In total, 96 samples were taken from influent and effluent of the wastewater plants at one week intervals for a period of 6 months for parasitic analysis by Mac master slide(with a hole size 0.3 ml) according to Bailenger method. Data were analyzed using SPSS software. Average removal efficiency of constructed wetland for parasitic eggs and protozoan cysts were 99.7-100% and 100%, respectively. These values for conventional activated sludge of Kermanshah were 97-99% and 99-100%. Statistically significant differences were observed in removal efficiency of the parameters studied between two treatment facilities (P<0.001). Based on the results obtained, removal efficiency for cysts and parasitic eggs in both treatment facilities are desirable with efficiency of constructed wetland being better than conventional activated system. In terms of number of nematode eggs, effluent quality of both treatment plants complies with Angelberg index (number of nematode eggs per liter ≤ 1).