Assessment of safety in drinking water supply system of Birjand city using World Health Organization’s water safety plan

Background: The conventional method for managing drinking water quality is not a suitable preventive strategy for protecting public health. A water safety plan (WSP) presents a systematic approach to ensuring the health and quality of drinking water. This study assessed the drinking water supply system safety of Birjand city using the WHO’s WSP. Methods: This investigation employed the WSP-QA Tool and the WSP manual of the WHO and the AWI. For this purpose, software checklists were prepared and, after confirmation of content and face validity, completed based on Birjand’s water and wastewater company records and interview with company’s experts. Data was analyzed using WSP-QA Tool. Results: From total possible 440 points for full use of the program and 328 points of the studied phases, a score of 190 was acquired, indicating a 43.18% coordinated implementation with WSP. System description and management procedures showed the maximum and minimum percentages of congruency with the WSP of 87.5% and 25%, respectively. Among the components of the water supply system, water resource had the most attention. Conclusion: As regards the percentage of overall WSP-phase implementation and the low attention given to some key parameters of the water supply system, such as risk assessment and management procedures, the system currently enjoys a relatively medium level of safety. However, the high points of some phases such as system description, operational monitoring and verification enhance the system’s flexibility for changing the current approach of qualitative management to the WSP. Keywords: Drinking water, Safety, Water supply, Risk assessment, Softwar

Investigating the removal of hexavalent chromium from aqueous solutions by functionalized carbon derived from rice husk

Background and Aim: Hexavalent chromium is a heavy metal with harmful effects on surface and ground water. Its removal from contaminated water and waste water has received great interest in recent years. This study aimed to evaluate the absorption of hexavalent chromium from aquatic environments using functionalized carbon produced from rice husk as an inexpensive and biological adsorbent. Materials and Methods: This experimental study investigated the effects of pH (2-10), adsorbent dose (5-20 g/l), initial chromium concentration (5-20 mg/l), contact time (5-60 min), temperature (1-40 °C), and mixing rate (100-500 rpm) on removal of hexavalent chromium from aqueous solutions using functionalized carbon made from rice husk. The results of absorption in equilibrium conditions were analyzed by Langmuir isotherm model. UV/V Spectrophotometer T80+ was employed to assess the obtained samples of hexavalent chromium at a wavelength of 540. The diagrams were drawn using the Excel software. Results: The most efficient removal of hexavalent chromium occurred at pH=2 and optimal dose of 10 g/l. As the initial hexavalent chromium concentration increased from 5 to 20 mg/lit, the removal percentage from reduced from 97.3 to 85.7%. Additionally, along with increased contact time and mixing speed, the removal efficiency improved. Conclusion: Functionalized carbon derived from rice husk with a maximum efficiency of 97% is very effective in the removal of hexavalent chromium from aqueous solutions. &nbsp

The efficiency of magnetic carbon activated by iron oxide nanoparticles in removing of Cu (II) from aqueous solutions

Background and Aim: Copper ions, due to forming complexes with organic and mineral compounds, can have worrying effects on health and environment. In the present study, the effect of powdered magnetic carbon activated by iron-oxide nanoparticles in removing of CU (V; II) from aqueous solutions was assessed. Materials and Methods: This experimental study aimed at determining the effect of powdered magnetic carbon activated  by iron-oxide nanoparticles  parameters including PH, contact time, absorbing dose, and initial concentration on copper(II) removal .from aqueous solutions; through an indirect current. In order to assess the qualities of the synthetized adsorbent, TGA, FT-IR and SEM tests were applied. Residual concentration of copper was measured at 324nm wavelength by means of atomic absorption spectrometry flame. The obtained data was analyzed using Langmuir and Freundlich isotherm model. Result: It was found that synthetic nanoparticles(PH=10), with the adsorbent dosage of 1gr/l, can remove more than 96% of copper ions from aqueous solutions at 2 minutes. Also, the results showed that copper absorption pattern is more in accord with Langmuir model.  Conclusion: Based on the current findings , magnetic synthesized nanoparticles coated with carbon. are in sporadic form in aqueous solutions. and can easily be separated using external magnetic environment. Moreover, because of existant active carbon sites absorption in iron oxide structure suferficial absorbtion capacity increases and and these nanoparticles reveal to have a high performance in the removing process of copper pollutants from aqueous solutions

Decolorization of Reactive Red 198 by means ofpistachio-nut shell ash

Background and Aim: Reactive dyes have extensively been used in textile industries during last year's due to their superior performance, but the effluence of the waste containing such dyes into water resources can pose hazardous effects on the environment and to the human health because of their carcinogenic, mutagenic, allergenic and toxic nature. The present research was performed to study the efficiency of pistachio-nut shell ash in removing Reactive Red 198 dye from aqueous solutions. Materials and Methods: In the present experimental study, effects of various operating parameters such as initial concentration of dye (20-200 mg/L), contact time (5-270 mines), adsorbent dosage (0.1-5 g/L) and pH (2-12) were investigated. Results: Maximum adsorption capacity of the pistachio-nut shell ash was 238.1 mg/g at pH 2, contact time 60 minutes and adsorbent dosage 0.3 g/L. Besides, the equilibrium data were also fitted into the Langmuir and Freundlich equilibrium isotherm models. It was found that the data fitted into Freundlich (R2=0.9352) model in a better extent than into Langmuir's (R2=0.8868). Conclusion: According to results of the present study, it was found that pistachio nut-shell has a high capacity to remove Reactive Red 198 dye from aqueous solutions and textile industry wastewater

Investigation of Cr(VI) removal from aqueous solutionsefficiency by almond green hull and its ash

Background and Aim: Hexavalent chromium is a metal, which causes harmful effects in surface and ground water, Its removal from contaminated water and waste water has received a great deal of interest in recent years. Thus, theaim of the presentstudy was a comparative analysis of the application of green almond hull and its resultant ash inremovingchromium from aqueous solutions. Materials and Methods: In this experimental study, the effects of variables such as pH of adsorbent dose, initial chromium concentration, contact time, temperature, and adsorbent characteristics of almond hull and its resultant ash on removing of chromium from aqueous solutions were investigated. Experiments were intermittently performed in batch reactor on Shaker. Finally, in order to assess the obtained samples colorimetricmethod using UV/V Spectrophotometer T80+ set, at a wavelength of 540, was applied. Results: The most efficient removal of hexavalent chromium occurred when pH was 2. Furthermore, it was found that removal percentage increased parallel to contact time and temperature. But, when the bioabsorbent and the resultant ash were used, a decrease in the initial hexavalent chromium density from 100 to 10mg/lit led to a decrease in the removal percentage from 99/66% to 61/19% and 78/93% to 37/01%, respectively. It was found that by increasing the absorbent dose (i.e. the bioabsorbent) the removing percentage tended to its extreme level (100%). However, when the absorbent ash was used, removing percentage increased at first, but then it decreased. Conclusion: Both almond green hull and its resultant ash are agents which cause effective removing of hexavalent chromium from aqueous solutions

Assessment of safety in drinking water supply system of Birjand city using World Health Organization’s water safety plan

Background: The conventional method for managing drinking water quality is not a suitable preventive strategy for protecting public health. A water safety plan (WSP) presents a systematic approach to ensuring the health and quality of drinking water. This study assessed the drinking water supply system safety of Birjand city using the WHO’s WSP. Methods: This investigation employed the WSP-QA Tool and the WSP manual of the WHO and the AWI. For this purpose, software checklists were prepared and, after confirmation of content and face validity, completed based on Birjand’s water and wastewater company records and interview with company’s experts. Data was analyzed using WSP-QA Tool. Results: From total possible 440 points for full use of the program and 328 points of the studied phases, a score of 190 was acquired, indicating a 43.18% coordinated implementation with WSP. System description and management procedures showed the maximum and minimum percentages of congruency with the WSP of 87.5% and 25%, respectively. Among the components of the water supply system, water resource had the most attention. Conclusion: As regards the percentage of overall WSP-phase implementation and the low attention given to some key parameters of the water supply system, such as risk assessment and management procedures, the system currently enjoys a relatively medium level of safety. However, the high points of some phases such as system description, operational monitoring and verification enhance the system’s flexibility for changing the current approach of qualitative management to the WSP

Application of Moringa Peregrina seed extract as a natural coagulant for Phenol removal from aqueous solution

Background and Aim: Phenol and its derivatives are toxic pollutants, frequently found in surface and tap waters, and in aqueous effluents from various manufacturing processes such as petroleum and petrochemical, coal conversion, synthetic rubber, plastics, paper, oil refineries and phenol-producing industries. In the present study efficacy of Moringa peregrina seed extract in phenol removal was investigated. Materials and Methods: The present research was an experimental one performed in a batch system to find out the efficacy of Moringa peregrina seed extract, as a natural coagulant, in removing phenol from aqueous solutions. To do so, the effects of major operating variables such as coagulant dose (0.05–4 ml/L), initial phenol concentration (5, 10, 20, 50 and 100 mg/l) and pH (3-9) were also investigated. Results: It was found that the optimum pH for phenol removal through coagulation using Moringa peregrina seed extract was 5 with coagulant dose 0.1 ml/L and the highest removal was found to be 94.13%, 95.69%, 98.04%, 98.14% and 99.34% at initial phenol concentration 5, 10, 20, 50 and 100 mg/L respectively, as a result of precipitation, co-precipitation and adsorption mechanisms. Conclusion: According to the obtained results, Moringa peregrina seed extract, with respect to its high efficacy, can be used as an effective, efficient, and inexpensive coagulant in removing phenol from aqueous environments

Evaluation of Vali Asr (aj) hospital effluent for irrigation of the green

Background and Aim: Recycling of sewage in our country can be one of the ways to overcome the problem of water shortage. The aim of this paper is Evaluation of Valli-e-asr hospital effluent for irrigation of the green. Materials and Methods: During the 12 months of the project since January 2009, twelve samples of the hospital water were selected. 35 samples were taken both from raw sewage and refined effluent with the average frequency of two samples every month. Various physical, chemical, and biological factors were measured on the basis of the standard method book (AWWA). The gathered data was statistically analyzed using SPSS software (version 15) and paired T test at the significant level . Results: The percentages of separating some parameters such as BOD, TSS, COD, and MPS in the exiting effluent were 63.56%, 44.9%, 42.9%, and 89.97% respectively and those of the parameters PH, Mg, SO4, and SAR were 7.52mg/l, 66.82 mg/l, 382.14 mg/l, and 0.54 mg/l respectively. The amount of parameters BOD, COD, TSS, MPN, EC, CL, TDS, and NA% were 165.14mg/l, 887.657mg/l, 784.4286mg/l, 1856857 MPN, 4137.97µs/cm, 999mg/l, 2866.57mg/l, and 75.11% respectively. Conclusion: The sewage refinery of Valli-e-asr hospital does not produce a favorable outcome and some of the parameters of the effluent such as PH, Mg, SO4, and SAR are in accord with the standards of reusing in agriculture and irrigation but many of the necessary parameters do not correspond with the necessary standards for this task

Efficacy evaluation of activated carbon prepared from date stones in cyanide adsorption from synthetic wastewater

Background and Aim: Availability and low cost of date stones make them useful as raw material in the preparation of activated carbon. Cyanide, because of its toxicity for humans and aquatic organisms, is one of the most important health problems. The aim of the present study was to evaluate cyanide removal from aqueous solutions and determine influencing parameters in its adsorption into activated carbon prepared from date stones. Materials and Methods: In this experimental study, activated carbon was prepared by using an electrical furnace giving out 750°C temperature for 100 min. The effect of pH (2-12), cyanide concentration (100-300 mg/L) and activated carbon dosage (0.25-2 g/L) on the absorption process were explored. All experiments were conducted in triplicate and the mean absorption rate was reported. Results: The maximum adsorption capacity of 50.21 mg/g corresponded with Langmuir model. Kinetic evaluation indicated that the adsorption of cyanide ions by the adsorbent clearly followed the pseudo-second order rate reaction. The absorption was pH dependent and the maximum adsorption was done by solutions having pH 9. At an optimum pH 9, over 97% removal of 100 mg/L cyanide was attained for an adsorbent dose of 1.25 g/L during a 40 min contact time. Conclusion: Activated carbon prepared from date stones is an efficient and low-cost adsorbent for removing of different concentrations of cyanide from water and wastewater

Adsorption of tetracycline on polyvinyl chloride microplastics in aqueous environments

Abstract Microplastics (MPs), as carriers of organic pollutants in the environment, have become a growing public concern in recent years. Tetracycline (TTC) is an antibiotic that can be absorbed by MPs and have a harmful effect on human health. Therefore, this study was conducted with the aim of investigating the adsorption rate of TTC onto polyvinyl chloride (PVC) MPs. In addition, the adsorption mechanism of this process was studied using isothermal, kinetic, and thermodynamic models. For this purpose, experimental runs using the Box-Behnken model were designed to investigate the main research parameters, including PVC dose (0.5–2 g/L), reaction time (5–55 min), initial antibiotic concentration (5–15 mg/L), and pH (4–10). Based on the research findings, the highest TTC adsorption rate (93.23%) was obtained at a pH of 10, a contact time of 55 min, an adsorbent dose of 1.25 g/L, and an antibiotic concentration of 10 mg/L. The study found that the adsorption rate of TTC followed the pseudo-second-order and Langmuir models. Thermodynamic data indicated that the process was spontaneous, exothermic, and physical. Increasing ion concentration decreased TTC adsorption, and distilled water had the highest adsorption, while municipal wastewater had the lowest adsorption. These findings provide valuable insights into the behavior of MPs and organic pollutants, underscoring the importance of conducting additional research and implementing measures to mitigate their detrimental effects on human health and the environment