Health and environment
mostafa baghani; Abolfazl Rahmani Sani
Volume 30, Issue 1 , May and June 2023, , Pages 13-21
Abstract
Introduction: Population growth causes the need to produce more agricultural products. And the lack of water causes people to use unconventional waters, including treated sewage. Improper quality of wastewater can be harmful to the soil, plants and the health of consumers. Therefore, it is necessary ...
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Introduction: Population growth causes the need to produce more agricultural products. And the lack of water causes people to use unconventional waters, including treated sewage. Improper quality of wastewater can be harmful to the soil, plants and the health of consumers. Therefore, it is necessary to measure and check their quality.Materials and Methods: In this study, the factors of EC, BOD, COD, TSS, TN, TP, PH, Ecoli, TC, CL,Ca, Mg, Na, SAR in effluent treatment plants, Sabzevar stabilization pond, activated sludge (Factory sanitary wastewater) and rural Wetland with Tested by standard methods. (according to 2017 version of the book Standard Methods for the Examination of Water and Wastewater) and compared with Wilcox, Ayers and Westcot, FAO, WHO, USEPA standards.To determine the competence of three different types of effluent for agricultural use.Results: In accordence with the standards of Iran, Wilcox, Ayers and Westcot, FAO and WHO, all three types of effluent can be used for irrigation with low to moderate negative impacts. However, in the more stringent standards (USEPA), stabilization pond and Wetland did not meet the BOD, TSS factors threshold, and the activated sludge effluent did not provide the BOD factor.Conclusion: According to the results, the activated sludge treatment system meets the standards of wastewater consumption in agriculture better than the other two systems. Over time, the standards will become stricter. Choosing the type and correct operation of the treatment system has a significant impact on providing the quality standards of effluent for irrigation.
Health and environment
Ahmad Allahabadi; Abolfazl Rahmani Sani; MohammadHossein Saghi; Hamideh Behrozikhah; Shahram Sadeghi; Mohammadreza Behrouzikhah
Volume 26, Issue 1 , March and April 2019, , Pages 63-71
Abstract
AbstractBackground: One of the most important environmental pollutants that there is in sewage of different industrials is cyanide to cause pollution of water sources that are dangerous to humans and the environment. Cyanide can be removed in different ways from the aqueous media, but most of these methods ...
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AbstractBackground: One of the most important environmental pollutants that there is in sewage of different industrials is cyanide to cause pollution of water sources that are dangerous to humans and the environment. Cyanide can be removed in different ways from the aqueous media, but most of these methods are costly. Therefore, the aim of this study is the removal cyanide using iron nanoparticles. Material and Methods: Removal of cyanide from aqueous media using iron nanoparticles in various conditions including the effect of the adsorbent, initial cyanide concentration, contact time and pH were studied in discontinuous phase. In this study, adsorption equilibrium and also the kinetics of the reaction examined.Results: In the process of sharing discontinuous, the balance was achieved after 120 minutes of contact time and maximum amount of removal cyanide in the pH =11 for cyanide concentration of 2.5 mg/L and 1 gr of nanoparticle over 97% obtained. Also the results showed that the adsorption process fitted with Langmuir isotherm and chemical kinetic fitted with of secondary grade.Conclusion: According to the findings, iron nanoparticles can be used as a suitable option for removal cyanide from aqueous solution in hazardous waste. Keywords: iron nanoparticles, cyanide, hazardous waste
Health and environment
Akram Eskandariyan; Sahar Sadat Azad; Abolfazl Rahmani Sani; Ayoob Rastegar; Ahmad Alahabadi
Volume 24, Issue 3 , July and August 2017, , Pages 183-189
Abstract
Background& Objectives: Antibiotics are a group of synthetic organic materials that are not removable by biological treatment process and need to be treated by advanced process like surface absorption. Since activated carbon is one of the best choices for using as adsorbent, this project was aimed ...
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Background& Objectives: Antibiotics are a group of synthetic organic materials that are not removable by biological treatment process and need to be treated by advanced process like surface absorption. Since activated carbon is one of the best choices for using as adsorbent, this project was aimed on the removal of amoxicillin antibiotic from aquatics solutions by a novel modified activated carbon.
Materials & Method: The present study was an experimental study which was conducted by using batch wise method. Erlenmeyers with 100 mL volume containing 50 mL of amoxicillin with a known concentration and amount of adsorbent were shacked at different pHs, contact times and temperatures. The samples were filtered by vacuumed pump using 0.04 acetate cellulous filter and the residual of amoxicillin was determined by UV spectrophotometer at 228 nm using quarts cell.
Results: The results obtained from experimental data was shown that the best efficiency of amoxicillin removal from aquatic solution by the new activated carbon takes places at pH= 6, adsorbent dose of 0.06 g/L and 20 min contact time. In this project the used activated carbon efficiency was 75.5%, in antibiotic concentration of 50 mg/L. Isotherm studies were shown that the amoxicillin absorption can be explained by both Langmuir and Freundlich models, and the degree of reaction obtained from kinetic studies was of second order.
.Conclusion: With regard to acceptable worth capacity of the new activated carbon, it was suitable to replace standard Merck carbon for water and wastewater treatment.
Seyyed Hossein Hosseini; Ahmad Hosseini; Ahmad Allah abadi; Abolfazl Rahmani sani; Zakiyeh Mojarrad
Volume 22, Issue 5 , November and December 2015, , Pages 879-892
Abstract
Background & Objectives: Despite the great importance of determination of radioactive elements in the environmental samples, most of analytical instruments have not the necessary sensivity for this purpose. Pre-concentration and separation of elements from the sample matrixes is the best and often ...
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Background & Objectives: Despite the great importance of determination of radioactive elements in the environmental samples, most of analytical instruments have not the necessary sensivity for this purpose. Pre-concentration and separation of elements from the sample matrixes is the best and often the only practical method for solving this problem and the purpose of the present research is solidphase extraction of uranium and thorium, using a selective and suitable sorbent, and precise determination of their ultra-trace concentrations in the environmental samples.
Materials & Methods: In this experimental study, Amberlite XAD-7 resin was impregnated with Clayton yellow and used for pre-concentration and determination of uranium and thorium in the environmental samples and, after investigating the optimum conditions of pH and ionic strength and studding equilibrium aspects of sorption process, determination of uranium and thorium was performed, using arsenazo III procedure, after their pre-concentration by the column method. In the column method, some variables such as sample flow rate, eluent type, eluent concentration, elution rate, eluent volume and tolerable concentration of interference ions were also optimized precisely.
Results: Optimization of pH and ionic strength showed that uranium and thorium can be simultaneously sorbed at pH 5. The equilibrium data obtained from the sorption experiments were adjusted to the Langmuir isotherm model (R2=0.9999)better than Freundlich (R2≤0.8979) and Tempkin (R2≤0.9705) models and the calculated maximum sorption capacities in terms of monolayer sorption were 0.609 and 0.571 mmol g-1 for uranium and thorium, respectively. The flow rates in both sorption and elution processes was desirable.The studies showed that, after simultaneous adsorption, the analyte ions can be separated by sequential elution with 0.5% (w/v) Na2CO3 for uranium and 2.0 mol L-1 HCl for thorium. The limits of detection for U(VI) and Th(IV) were as low as 50 and 25ng L-1, respectively. Relative standard deviations (RSDs, n=7) for U(VI) and Th(IV) were 3.1% and 2.9%, respectively. The interference effects of foreign ions on the retention of the analyte ions were ignorable. The method was successfully applied to determination of ultra trace amounts of U(VI) and Th(IV) in different real matrices including industrial wastewater samples and environmental waters.
Conclusion: According to the obtained results, it is proposed that CY/XAD-7is very desirable for pre-concentration and determination of ultra-trace amounts of U(VI) and Th(IV) in the environmental samples.
Ayyob Rastegar; Zahra Rezaee Gezal Abad; Ahmad Allahabadi; Abolfazl Rahmani Sani; RamezanAli Khamirchi
Volume 21, Issue 6 , January and February 2015, , Pages 1090-1102
Abstract
Background: Aniline is an important chemical compound which has wide applications in several industries such as dyestuffs, rubbers, pesticides and plastics. It is highly toxic and has injurious influences on human physical conditions and aquatic life. Therefore the purpose of this study is to investigate ...
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Background: Aniline is an important chemical compound which has wide applications in several industries such as dyestuffs, rubbers, pesticides and plastics. It is highly toxic and has injurious influences on human physical conditions and aquatic life. Therefore the purpose of this study is to investigate the effects of NH4Cl-induced activated carbon (NAC) and standard activated carbon (SAC) in aniline removal from aqueous solutions were investigated. Material & method: This study is of experimental–intervention type. An UV-Visible spectrophotometer (CECIL CE7400) used For determination of remaining aniline concentrations. The effect of various parameters like adsorbent dose, pH, contact time and initial aniline concentration were studied for optimization.
Results: The results showed that the prepared NAC had a higher absorption capacity than standard activated one. The maximum adsorption capacity of aniline onto SAC and NAC was 1666 and 1000 mg/g, respectively, and the rate removal was dependended to pH, contact time, aniline concentration and absorption type. Results of equilibrium experiments indicated that the adsorption process of aniline onto SAC and NAC follows Langmuir model (R 2> 0.99.47 and 0.99,776 ). Also, kinetics of adsorption process follows pseudo second-order model with correlation R2> 0.99.97 and 0.99,30 respectively for SAC and NAC.
Conclusion: These consequences show that the developed NAC was a more competent adsorbent than SAS for removal aniline in water.
Mehran Eyvazzadeh; MohammadHasan Rakhshani; Ayyob Rastegar; Ahmad Allahabadi; Ebrahim Manochehriyan; Fatemeh Dareyni; Abolfazl Rahmanisani
Volume 21, Issue 5 , September and October 2014, , Pages 934-941
Abstract
Background: In recent years, crisis of water shortage has become a serious problem in many countries. In this regard, the use of treated wastewater in natural or artificial method in agriculture and the like, has been proposed as an important and practical solution. The natural purification method by ...
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Background: In recent years, crisis of water shortage has become a serious problem in many countries. In this regard, the use of treated wastewater in natural or artificial method in agriculture and the like, has been proposed as an important and practical solution. The natural purification method by the use of artificial canebrakes, compared with other methods of treatment is an appropriate method because of its low cost, and also, because of easy navigation, the requirements of low technology and low energy consumption. Several herbs have been used to increase the efficiency canebrakes which including special plants to purify such wastewater is Vetiveria that has unique genetic, morphological and physiological characteristics. Due to the limited knowledge of the plant's industrial wastewater treatment, in this study, a comparison of filterablity of hospital wastewater was done between Vetivaria and bulrush in tropical areas.
Methods: This experimental study was done in 2013 in the hot season, summer. In this study, was made two pilot glass with dimensions of 50*60*100 Cm. A mixture of soil, sand, gravel, clay soil was selected. The irrigation method in this study was subsurface and continuous. First, hospital wastewater via a 220 liter tank as the primary sedimentation retention time and with time of 2 hours entered into bed with a hydraulic retention time of 4 days to discharge 85/0 liters per hour. To evaluate the efficiency of each plant in the treatment of hospital wastewater, chemical parameters including (PH, TP, TN , TSS, BOD5, COD)were measured according to standard methods of measuring. . Analysis of the data was done by the use of t-test and Mann-Whitney and SPSS software.
Results :Based on the finding of this study, percentage of removal parameter(Bod5,Tss,Tn,Tp) by plant Vetiveria was (88.54,95.71,93.93,99.80) and for bulrush was (82.54,91.13,86.64,99.28).
Conclusion: Due to the unique characteristics of Vetiveria, such as high resistance against unfavorable environmental conditions and its higher efficiency than bulrush, this plant is recommended for the treatment of hospital wastewater.
Tahereh Vazeiri; Abolfaz Rahmani Sani; Ahmad Allahabadi; MohammadHossein Saghi; Reza Hekmatshoar
Volume 19, Issue 2 , May and June 2012, , Pages 127-135
Abstract
Background: The biosorption process has found numerous applications due to low cost, availability, biosorbent reuse, and utilization of excess sludge from wastewater treatment facilities. The aim of the present study was to evaluate the efficiency of dried activated sludge in removing Reactive Orange ...
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Background: The biosorption process has found numerous applications due to low cost, availability, biosorbent reuse, and utilization of excess sludge from wastewater treatment facilities. The aim of the present study was to evaluate the efficiency of dried activated sludge in removing Reactive Orange 3R dye. Materials and methods: For this experimental, laboratory study, dye solutions were prepared in three concentrations: 50, 100, and 150 mg/L. The solutions were then subjected to adsorbent in weights 0.2, 0.4, 0.6, 0.8, and 1.0 g for various durations (0.5, 1, 1.5, 2, 2.5, and 3 hours) in different pH levels (4, 7, and 12). Data was analyzed using Excel software. Results: Increasing contact time from 0.5h to 3h, the dye removal efficiency increased from 56% to 76%. When the weight of the biomass increased from 0.2g to 0.8g, the dye removal efficiency increased from 58% to 72%. High initial iron concentration had an adverse effect on iron removal efficiency. Increasing initial dye concentration from 50 to 150 mg/L decreased iron removal efficiency from 71% to 62%. Freundlich isotherm models could describe the adsorption equilibrium of the dye onto the activated sludge. Freundlich isotherm represented a better correlation compared to other isotherms (R2>0.952). Also, second-order models fit well with experimental data (R2>0.979). Conclusion: This technology for dye removal from industrial wastewater, in addition to the optimal use of biomass from wastewater, can help resolve the environmental problem of wastewater dye excretion.
Ahmad Allahabadi; AliAkbar Azimi; Naser Mehrdadi; Abolfazl Rahmani Sani; Ali Torabian
Volume 18, Issue 1 , March and April 2011, , Pages 33-40
Abstract
Background and Purpose: Subsurface flow wetlands are one of the successful treatment methods used for municipal and industrial wastewater treatment، and are economical in terms of energy consumption and workforce. Much research has been conducted on wetland operation output in wastewater treatment، ...
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Background and Purpose: Subsurface flow wetlands are one of the successful treatment methods used for municipal and industrial wastewater treatment، and are economical in terms of energy consumption and workforce. Much research has been conducted on wetland operation output in wastewater treatment، but no enough information is available on their start-up and maintenance. The present study investigates the circumstance of starting up and implementing a wetland.
Methods and Materials: In this experimental study، two subsurface flow wetlands with a two-day detention time and two pretreatment units were built. The former was similar to Primary Settling tank with a 4-hour detention time and the latter was similar to anaerobic pond equipped a with digestion pit with a two-day detention time in a pilot scale. The wastewater (BoD5 = 250 mg/l، Tss=320 mg.l and ph=7.2) from municipal network in Sabzevar، Iran was used for irrigation; the pilot implementation and maintenance took one year.
Results: Pilot operation indicated that the principal factors in implementing subsurface flow wetland were temperature، non-penetrateability of the bed، and wastewater ingredients. However، pretreatment and bed obstruction were the limiting parameters of the wetland maintenance.
Conclusion: Pretreatment of the subsurface flow of wetlands does not yield a high output; and if anaerobic ponds equipped with digestion pits are used، the treatment output is significantly enhanced، and the wetland operation will face minimum barriers.
AA AZIMI; A RAHMANI SANI; N MEHRDADI
Volume 14, Issue 4 , January and February 2008, , Pages 198-204
Abstract
Background and Purpose: Waste stabilization ponds as a natural treatment method have been found among successful methods in municipal wastewater treatment. They are very costeffective in energy and manpower. Low efficiency rates and vast area required are some of their drawbacks which are less attended ...
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Background and Purpose: Waste stabilization ponds as a natural treatment method have been found among successful methods in municipal wastewater treatment. They are very costeffective in energy and manpower. Low efficiency rates and vast area required are some of their drawbacks which are less attended to. Therefore this study intends to research the optimization methods in anaerobic ponds.
Methods and Materials: In this experimental study, two anaerobic ponds were built in pilot scale with 48 hours detention time, 12 m2 area (6x2 m) and 4m depth. The control pond was a conventional pond; the optimized pond was built in two parts: a digestion pit and a detention time of 12 hours, and the anaerobic pond with 8 baffles with a detention time of 36 hours. The wastewater with BOD5=250 mg/l and TSS=320 mg/l from municipal network in Sabzevar, Iran was used; the pilot took one year from December 2006 to December 2007. The collected data were analyzed in Excel and Tsp7.
Result: Average removal efficiency for BOD5 and TSS in the conventional pond were 37% and 53% respectively; the figures for the optimized pond were 68% and 85% respectively. Conclusion: Using optimized anaerobic ponds enhances the removal efficiency rate.