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Showing 5 results for Zoqi
Neural Network Modeling and Prediction of Methane Fraction in Biogas from Landfill Bioreactors
M.j Zoqi, A Ghavidel,
Volume 2, Issue 2 (16 2009)
Abstract

Backgrounds and Objectives:A number of different technologies have recently been studied todetermine the best use of biogas, however, to choose optimize technologies of using biogas for energy recovery it is necessary to monitor and predict the methane percentage of biogas. In this study, a method is proposed for predicting the methane fraction in landfill gas originating from Labscalelandfill bioreactors, based on neural network.
Materials and Methods: In this study, two different systems were applied, to predict the methane fraction in landfill gas as a final product of anaerobic digestion, we used the leachate specifications as input parameters. In system I (C1), the leachate generated from a fresh-waste reactor was drained to recirculation tank, and recycled. In System II (C2), the leachate generated from a fresh waste landfill reactor was fed through a well-decomposed refuse landfill reactor, and at the same time, the leachate generated from a well-decomposed refuse landfill reactor recycled to a fresh waste landfill reactor.
Results: There is very good agreement in the trends between forecasted and measured data. R valuesare 0.999 and 0.997, and the obtained Root mean square error values are 1.098 and 2.387 for training and test data, respectively
Conclusion: The proposed method can significantly predict the methane fraction in landfill gasoriginating and, consequently, neural network can be use to optimize the dimensions of a plant using biogas for energy (i.e. heat and/or electricity) recovery and monitoring system.


Prediction of landfill leachate amount using HELP model Case study: Semnan landfill
M.j Zoqi, A Ghavidel,
Volume 4, Issue 1 (24 2011)
Abstract

Background and Objectives:. Owing to the non-seperated municipal solid wastes the leachate form in land fills contain high amounts of heavy metalls and toxic substances Hence, leachate treatment is a serious problem. In order to design leachate treatment and collection systems, estimation of quality and quantity of leachate is of high necessity. Hydrologic Evaluation of Landfill Performance (HELP) Model was used to estimate leachate generation in the lined landfill cells for a variety of conditions. The HELP program is a quasi-two-dimensional hydrologic model for conducting water balance analysis of landfills, cover systems, and other solid waste containment facilities. In this paper HELP program is used to predict leachate generating in Semnan landfill after its operational life.
Materials and Methods: HELP model use weather, soil and design data to estimate leachate quantity. The meteorological data were obtained from semnan Atmospheric Data Centre. Soil mechanics examinations in the landfill area were applied to achieve soil data. In addition, design parameters were based on Semnan landfill design specifications. Semnan landfill capacity is designed so as to accommodate municipal solid wastes generated during the next 25 years.
Results: In this study result indicated that precipitation and evapotranspiration has the most influenced on leachate generation increase and decrease, respectively. 82% of annual precipitation isn't percolated into Semnan landfill due to evapotranspiration. HELP Model simulations were indicated that the maximum and average value of leachate height above barrier layer is 36 and 3mm,respectively.
Conclusion: Semnan landfill is designed under minimum standard condition. Therefore, low height of leachate generated is due to area weather. The precipitation amount is low while the evapotranspiration amount is high in this area. High evapotranspiration is due to high temperature and solar radiation in Semnan landfill area. High evapotranspiration in the landfill cap caused 14.2% of the precipitation to infiltrate into the wastes and became leachate.


Evaluation of the performance of conventional and baffled horizontal subsurface constructed wetland in the removal of Reactive Red 198
Hadi Entezari Zarch, Mohamad Javad Zoqi, Mohamad Reza Doosti, Somayeh Rahmani,
Volume 13, Issue 1 (4-2020)
Abstract

Background and Objective: Reactive Red 198 is a mono azo dye widely used in the textile industry of Iran. The toxicity of reactive dyes is higher than other dyes and causes disorders such as irritation, cancer and mutation in humans. The overall objective of this study was to determine the efficiency of a Constructed Wetland pilot system with conventional and baffled horizontal subsurface flow to remove Reactive Red 198.
Materials and Methods: In order to remove Reactive Red 198, two cells were constructed in parallel with 2 × 0.6 × 0.5 m. In the conventional and baffled cell, native straw of Phragmites australis was used. In the research process, COD concentration and reactive dye concentration were investigated. The effect of retention time and type of plant on the efficiency were also investigated.
Results: The results showed that the maximum removal efficiency of the Reactive Red dye 198 was obtained at 100 mg/L inlet pollutant concentration and 3.5 days retention time, which was related to the baffled cells. Also, the presence of the baffles in the constructed wetland system increased the removal efficiency. The presence of straw in both cells was directly affected the removal efficiency. The effect of the retention time in the conventional cell was more effective in removal efficiency than the baffled cell. The pollutant inlet concentration was also inversely correlated with the removal efficiency.
Conclusion: According to the results, it can be concluded that the baffled and conventional horizontal subsurface constructed wetland can be used for low concentrations and at low retention time as a well-functioning system in the removal of Reactive Red 198.


Application of response surface methodology to optimize the ultraviolet/hydrogen peroxide process for the removal of Reactive Red 195 dye from aqueous solution
Mohamad Javad Zoqi,
Volume 14, Issue 3 (12-2021)
Abstract
Background and Objective: The most used dyes in textile industries are Azo Group dyes. Azo dyes have complex aromatic compounds, low chemical and biodegradable stability. Due to these properties, treatment of this type of wastewater by conventional methods will not meet environmental standards. The advanced oxidation process has been widely used to treat organic matter from wastewater. In this study, dye purification of azo dye Reactive Red 195 by UV/H2O2 process was investigated. Moreover, the parameters affecting this process have also been determined.
Materials and Methods: In this study, dye treatment was conducted in the presence of different concentrations of hydrogen peroxide, and at different retention time, temperature and pH values in a continuous photoreactor equipped with UV lamps. Using central composite design and response surface methodology (RSM), effects of various concentrations of hydrogen peroxide, retention time, temperature, and pH on the color and COD removal were studied in the range of 0–2%, 60-240 min, 25-80 oC, and 3-10, respectively.
Results: The results showed that the concentration of hydrogen peroxide and retention time were the most influential parameters on color and COD removal. Color removal significantly enhanced by increasing retention time and H2O2 concentration to 200 min and 1.2%, respectively. pH increase had positive effect on color removal. There were increases in the rate of color and COD removal as the temperature went up to 50 oC. However, temperature of 80 oC negatively impacted AOP process. According to RSM, the optimum factor levels were achieved at 1.28%, 240 min, 49 oC and 10 for concentrations of hydrogen peroxide, reaction time, temperature, and pH, respectively.
Conclusion: According to the result, UV/H2O2 proved to be capable of degrading Reactive Red 195. Almost all the azo dye color destroyed after 209 min while 87.52 % of the COD was removed after 240 min of irradiation.

Efficiency of the electrokinetic process in copper recovery from the waste of the mine
Mohammad Javad Zoqi, Mohammad Amin Rasooli, Behnoosh Khataei, Mohammad Reza Doosti,
Volume 16, Issue 2 (9-2023)
Abstract
Background and Objective: Mining is one of the important economic activities all over the world. It causes the release of various emissions, especially heavy metals in the soil, due to the weak exploitation and improper disposal of mineral wastes. Different techniques are used for soil remediation and heavy metal extraction; including the electrokinetic method (so effective in fine-grained soils). In this research, the electrokinetic process was used to extract copper from the waste of the mine in Birjand.
Materials and Methods: In this research, a 24 cm long PVC reactor was used. The retention time was 2, 4, and 6 days and the voltage gradient was 1 V/cm. Graphite electrodes and electrolyte solutions of nitric acid and citric acid were investigated for copper extraction. The electrode polarity was alternately changed in order to pH control and improve the extraction process.
Results: According to the results, the highest removal efficiency (54%) was obtained after 6 days using 0.1 M citric acid and distilled water in the anode and cathode reservoir, respectively. Further, by 24-hour polarity reversing, the copper removal efficiency increased to about 60%.
Conclusion: The use of citric acid in anode was more effective than nitric acid, leading to more copper removal. In addition, by periodically polarity change and keeping the soil pH in the neutral range, further dissolution of the metal and reducing its sedimentation in the soil occurred. As a result, the rate of its transfer outside the treatment area and removal efficiency increased.
 

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