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Avicenna Journal of Environmental Health Engineering - Volume:3 Issue: 2, Dec 2016

Avicenna Journal of Environmental Health Engineering
Volume:3 Issue: 2, Dec 2016

  • تاریخ انتشار: 1395/10/08
  • تعداد عناوین: 8
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  • Ali Almasi, Mohammad Soltanian, Fateme Asadi, Parvin Nokhasi, Kazem Godini, Mitra Mohammadi, Ghasem Azarian, Ahmad Mohammadi Page 1
    Tetrachloroethylene (TCE) is a chlorinated aliphatic hydrocarbon, used in many industries. Effective and efficient treatment of industrial wastewater, containing TCE, is one of the environmental requirements. The purpose of this study was to determine the role of alkaline environments in TCE removal rate from aqueous solutions, using copper-doped pumice. This experimental study was performed, using granulated pumice stones with a mesh 4 (8.4 mm) in alkaline conditions; the samples were coated with copper. Copper-doped pumice was prepared as a bed at doses of 1, 2, and 3 g/L; the study was performed at pH ranges of 3, 7, and 11. Based on the results, copper-doped pumice showed good efficacy in TCE removal; in addition, its performance increased in alkaline conditions. Therefore, use of this stone for the treatment of wastewater, containing TCE, is effective due to its availability and low cost. Besides, it can be considered a good option, given its high efficiency in the absorption process.
    Keywords: Pumice, Copper, Tetrachloroethylene Removal, Alkaline Environments
  • Ali Reza Rahmani, Fahime Zamani, Amir Shabanloo, Halime Almasi * Page 2
    Azo dyes are the greatest classes of synthetic dyes, which are widely used in the textile industries. This study aimed at examining Acid Black 1 (AB1) removal from aqueous solution thermal activated persulfate using silica (SiO2). The effects of operational parameters such as initial pH, initial concentration of AB1, SiO2 dosage, and persulfate concentration were investigated and the chemical oxygen demand content was considered as a response. The results indicated that the removal efficiency had a direct relationship with concentration of SiO2 and persulfate up to their optimum values, and was inversely correlated with the alkaline pH and elevated concentrations of AB1. Moreover, the removal efficiency was increased significantly by increasing the silica concentration from 25 mg/L to 100 mg/L. Ultimately, AB1 was completely removed after 45 minutes.
    Keywords: Ultrasonic, Persulfate, Silica, Acid Black 1, Azo Dyes
  • Zeinab Atashzaban, Abdolmotaleb Seidmohammadi, Davood Nematollahi, Ghasem Azarian, Omid Heidary Shayesteh, Ali Reza Rahmani * Page 3
    Polyvinyl acetate (PVAc) is a type of thermoplastic resin generated by a polymerization of vinyl acetate. Effluent of this polymer is highly rich with chemical oxygen demand (COD) and total solids (TS). Due to lack of studies on the above problem, the current study aimed at obtaining a sufficient method for the effluent pre-treatment. In fact, the study discussed PVAC effluent treatment by electrocoagulation (EC) and electroflotation processes.The study considered the effect of various operating parameters such as pH and current density, initial concentration of pollutant, inter-electrode distance, electrolysis times, and types of electrode materials (iron and aluminum); COD and TS removal efficiency and optimal values of operational parameters were calculated. In the study, COD and TS reduction rates in the optimized conditions in batch flow reactor were 83% and 78%, and 80% and 72% for Fe and Al electrodes, respectively. Optimized conditions were taken as 24 mA cm -2, 20 g/L PVAC, and neutral pH in 20 minutes for Al-Al electrodes and 15 minutes for Fe-Fe electrodes, 1 cm distance between electrodes with parallel-type monopole of connection modes. According to the results, electrochemical process with batch flow tends to be a suitable pre-treatment process that is inexpensive, easily operated, and highly sufficient for effluent treatment, which contains polyvinyl acetate.
    Keywords: Effluent Treatment, Polyvinyl Acetate, Electrocoagulation, Electroflotation
  • Nahid Ghobadi, Reza Shokoohi, Ali Reza Rahmani, Mohammad Taghi Samadi, Kazem Godini, Mohammad Reza Samarghandi * Page 4
    In this study, the performance of a pilot-scale vermifilter (VF) for the treatment of hospital wastewater using the earthworm species Eisenia fetida was evaluated. The earthworms’ gut acts as a bioreactor and can ingest the wastewater solid and liquid organic wastes and expel these as vermicompost. A pilot-scale vermifilter was installed and operated for 133 days in one of hospitals in Hamadan city; the designed system was fed with the influent passed through coarse and fine grillage and the sedimentation tank of the hospital’s sanitary collection system. In order to study the efficiency of the system, the variations of pH value, chemical oxygen demand (COD), biochemical oxygen demand (BOD5), and total suspended solids (TSS) were measured. In addition, a conventional geofilter (GF) without Earthworm was used as the experimental control. The vermifiltration caused a significant decrease in the levels of COD (75%), BOD5 (93%), and TSS (89%) as well as neutralized pH in the wastewater. Also, these contents in the geofilter were observed to be 65%, 71%, and 71%, respectively. The vermifiltration technology can, therefore, be applied as an environmentally friendly method for hospital wastewater treatment.
    Keywords: Hospital Wastewater, Vermifiltration, Eisenia Fetida
  • Heavy Metal Levels and Potential Health Risk Assessment in Honey Consumed in the West of Iran
    Soheil Sobhanardakani *, Mona Kianpour Page 5
    Since the worldwide research on content of heavy metals in honey is narrow, this study was carried out to analyze heavy metals (Cd, Cr, Ni, and Zn) in honey and assess its associated health risk in Hamadan City, Iran, in 2015. Totally, 15 freshly ripened samples of honey were analyzed for heavy metals using ICP-OES with three replications after burning to ash and digesting with dilute nitric acid. The potential health index was then calculated. The results showed that the mean levels of Cd, Cr, Ni, and Zn in the honey samples were 63.18 ± 43.39, 58.05 ± 30.32, 56.15 ± 54.32, and 684.43 ± 190.43 µg kg-1, respectively. Also, the health risk assessment showed no potential risk for children and adults in relation to the consumption of honey in the studied region. According to the results of the current study, although there is no adverse effect for the local population through the consumption of honey, due to the increased discharge of pollutants especially heavy metals into the natural environment, it is very important to assess foodstuff before release to the consumer market.
    Keywords: Heavy Metals, Honey, Health Risk, Food Safety, Iran
  • Mohammad Taghi Samadi, Mostafa Leili, Hossein Haji Agha Alizadeh, Kazem Godini, Fatemeh Ahmadi * Page 6
    Despite fossil fuels, the energy supply from biogas process is of renewable energy resources; this kind of energy can be generated in all parts of the world. Thus, the potential of anaerobic co-digestion for production of methane from wastes of an industrial slaughterhouse and fruit and vegetable center in the Hamadan city, west of Iran, was investigated. The digester was operated under the mesophilic (35 - 37°C) condition for a period of 40 days with 3 different C/N ratios (20/1, 30/1 and 40/1). Before operation of digester, the amounts of C and N in the wastes were measured and during the experiments pH and composition of the biogas were determined. The cumulative amounts of the generated total biogas and methane at the 3 examined C/N ratios 20/1, 30/1 and 40/1 were, respectively 181, 201.7 and 162.5 L and 129.8, 149.2 and 114 L. The results indicated that the highest contents of biogas and methane (201.68 and 149.29 L, respectively) were obtained at C/N of 30 within 31 days.
    Keywords: Anaerobic Co-Digestion, Methane Production, Slaughterhouse Wastes, Fruit, Vegetable Wastes
  • Synthesis of Manganese Tetroxide Nanoparticles Using Precipitation and Study of Its Structure and Optical Characteristics
    Reza Shokoohi, Mohammad Taghi Samadi, Ghorban Asgari, Mohammad Vanaei Tabar *, Kazem Godini Page 7
    Considering extensive applications of manganese tetroxide nanoparticles in various industries due to its special properties, conducting studies on how to achieve more suitable ways to produce smaller nanoparticles is of great importance. In this study, nanoparticles of manganese tetroxide (Mn3O4) were synthesized by a co-precipitation method. In order to determine the characteristics of the structure, size, and specific surface of the resulting nanoparticles, techniques such as XRD, BET, BJH, FESEM, and FTIR were employed. Also, the nanoparticles were quantified with EDS and their colony size was examined using DLS experiments. The findings revealed a production of crystalline manganese tetroxide nanoparticles with a space group of 141/amd (S.G.) (141) and a molecular weight of 228.81 with the international code of ICSD Card # 89 - 4837. The specific surface area was 32.147 m2/g with a pore volume of 0.1041 cm3/g. The XRD and EDX analyses verify the production of the Mn3O4 nanoparticles. The size of the nanostructures is approximately 19 nm. The method used in this study could produce the Mn3O4 nanoparticles in a much easier way without the need for surfactants. Compared to the nanoparticles produced in other studies, the size of the nanoparticles produced in the present study is remarkably smaller. Moreover, less amount of the metal salt was used.
    Keywords: Mn3O4Nanoparticles Synthesis, Co-Precipitation, Structural Characteristics
  • Fatemeh Karimi, Mohammad Reza Samarghandi, Reza Shokoohi, Kazem Godini, Mohammad Reza Arabestani * Page 8
    Simultaneous presence of various antibiotics and bacteria in hospital wastewaters creates a suitable environment, in which the bacteria, such as enterococci become resistant to the antibiotics. The aim of this study was to evaluate the performance of different units of the hospital wastewater treatment plant (HWTP) to remove Enterococcus spp and Vancomycin-resistant Enterococcus (VRE). The study was performed on the 27 samples collected from HWTP in Hamedan, Iran during December 2014 to August 2015. Enterococcus spp and VRE were identified by biochemical tests and then the isolates were confirmed by PCR. Finally, the antibiotic susceptibility test was performed using disk diffusion methods. Of the 27 samples examined, 315 a total of enterococcal isolates were obtained. Of the 315 isolates of enterococci investigated, 162 (51.42%) were identified as E. faecium, 87 (27.61%) as E. hirae, 35 (11.11%) as E. faecalis, 11 (3.5%) as E. gallinarum, 7 (2.22%) as E. casseliflavus, 4 (1.26%) E. avium, and 9 (2.85%) isolates VR E. faecium.The results of antibiotic susceptibility testing showed that of the total 315 isolates, 146 (46.34%) were resistance to tetracycline, 9 (2.85%) were resistance to vancomycin and Teicoplanin. Lower antibiotic resistance was seen with Nitrofurantoin 2 (1.26%). This study indicates a high prevalence of multidrug resistance among E. faecium isolated from HWTP, thus, it could be considered as a threat to the health and safety of wastewater workers and even public health.
    Keywords: Vancomycin-Resistant Enterococci, Hospital Wastewater Treatment Plant, Enterococcus faecium, Enterococcus faecalis