Iranica Journal of Energy and Environment (IJEE)

102-112

Authors: K. Fahmida and I.M. Rafizul

The principle objective of this study was to evaluate the soil quality and the level of contamination of soil by heavy metals adapting various developed index in a selected waste disposal site at Rajbandh, Khulna, Bangladesh. To theses endeavor, ten soil samples were collected from the selected locations and then the relevant elements of Al, Fe, Mn, Cr, Cu, Pb, Zn, Ni, Cd, As, Co, Sb, Sc and Hg were measured and monitored using standard method. To estimate the contamination situation of soil, contamination factor (CF), enrichment factor (EF) and geo-accumulation index (Igeo) and potential ecological risk index (PERI) were computed using geological background values. In addition, for assessing soil quality, Pearson's correlation coefficients analysis was also performed. Furthermore, this study revealed that the values of CF and Igeo in soils around the waste disposal area affected from the contamination of heavy metals mostly by Pb, Cd and Sb. In contrast, Pearson's correlation indicated that the sources of metals are almost the same and these heavy metals might be derived from the waste accumulation activity. Dump sites have great potential for energy extraction if the high valued compounds to be extracted.

118-126

Authors: S. N. Larimi and B. Ayati

The present study used the adsorption process of activated carbon produced from agricultural wastes and the photocatalytic process of nano-ZnO to break down complex compounds available in removing Direct Blue 71 (henceforth, DB71). The two processes were done under three varied circumstances- adsorption/photocatalytic, photocatalytic/ adsorption, and simultaneous use of the processes. First, DB71 was exposed to activated carbon produced from walnut and almond shells and the efficiency achieved at equilibrium time (45 and 60 minutes) was 55 and 60 percent, respectively. Then, DB71 was exposed to different dosages of nano-ZnO to remove the dye completely. The result showed that amount of AC/ZnO in an optimum condition for two walnut and almond shell absorbents were 0.75/0.096 and1/0.096 g/L. Second, (photocatalytic/ adsorption) the complex compound of DB71 with a dosage of 0.024 g/L was broken down as a result of UV radiation. The experiment proceeded with different dosages of walnut and almond shells after achieving the efficiency of 50% in removing DB71 in the second process. The amounts of AC/ZnO were 0.75/0.024 and 1/0.024 for walnut and almond shells respectively under the optimum condition for the second process. In the third process advantages of the simultaneous use of photocatalytic and adsorption processes were taken in which different dosages of AC/ ZnO were used. Given the smaller dosages of nano-ZnO and less dye removal time, amounts of 0.75/ 0.288 g/L and 0.75/0.288 g/L were measured for walnut and almond shells. The findings show that photocatalytic/adsorption process was the more optimal process because of the less dosages of nano-ZnO, efficiency of removing DB71 and shorter dye removing time. Furthermore, the effect of the intensity of UV radiant on the efficiency and time of removing DB71 was also examined. The experiment revealed that removing COD in the optimum conditions were 47.22 and 49.6 and 62.23 and 63.15 percent using walnut and almond shell respectively both in the first experiment and the simulations use of adsorption and photocatalytic processes after 30 hours. While, in the second experiment (photocatalytic/ adsorption) 42.21 and 39.18 percent of COD were removed using walnut and almond shell respectively after 30 hours. The LC-mass test of photocatalytic/adsorption process also showed the degradation of DB 71 complex compounds.

136-141

Authors: M. Naghizadeh* , P. Mohammadi, H. Sheibani,M. A. Taher

This work is reported on the synthesis of Fe 3 O 4 /eggshell nanocomposites in the absence of any stabilizer or surfactant.Fe 3 O 4 magnetic nanoparticles were established on the egg shell nanocomposite. The nanocompositeshave shown high catalytic activities in the synthesis of Tetrahydrobenzo[b]pyran. These derivatives were synthesized via an one‐pot three‐component condensation of aromatic aldehydes with malononitrile and dimedonewith excellent yields in the presence of Fe 3 O 4 /eggshell nanocomposites as a highly efficient heterogeneous catalyst. The obtained catalyst was characterized by Fourier transform infrared spectroscopy (FT-IR), Field emission scanning electron microscopy (FE-SEM), X-ray diffraction analysis (XRD) and Vibrating sample magnetometer (VSM). The developed technique of nano-composite synthesis is energy efficient since the reactions carried out in single step. The present catalyst is possible to be used for the production of biodiesel.

147-151

Authors: P. Hartwig

The water quality in a river is influenced by discharge from the sewerage network. Through increased efficiencies of the wastewater treatment plants, the main deterioration comes from combined water overflow. In view to a reduction of the discharge from combined water outflow the increase of the influent to a wastewater treatment plant can be an efficient solution. The main bottleneck on the waste water treatment plant is the final clarifier with the limited capacity regarding sludge discharge from the biological stage. Through bypassing the aeration with combined water and a direct feed of the combined water into the final clarification the specific sludge volume loading, which is significant to the efficiency of the final clarification, will not be raised. But the adsorption capability of the aerated sludge, the sedimentation effect of the final clarification and the partial recirculation over returnsludge can be used for an elimination of suspended solids, COD, ammonia and phosphate from the combined wastewater. In large-scale tests in Wilhelmshaven (160,000 PE) removal efficiencies for the elimination in the bypass of 75 % of COD, 60 % of ammonia and 89 % of suspended solids were reached. In comparison with conventional procedures for combined water treatment (e.g. storage volumes, soil filter) the bypass technology has got the possibility to achieve a highly efficient and economical combined water treatment by using the capability of existing clarifiers. In the frame of the presentation the basics for this advanced solution will be explained and the results from the technical application will be demonstrated.

160-169

Authors: Ali M. AL-Salihi 1 and Safaa A. AL-Kinani 1,2 *

The present paper involves Outgoing longwave radiation (OLR) under clear-sky condition modeling employing three measured meteorological parameters (Air surface temperature, Relative humidity and Cloud fraction). Dataset retrieved from NASA Atmospheric Infrared Sounder (AIRS), from 2003 to 2015 was employed to develop two models to estimate OLR values in Iraq using the multiple linear regression (MLR) and Artificial Neural Network (ANN) approach. For the entire period, the mentioned meteorological parameters were highly correlated with estimated OLR. Comparisons among selected cities (Mosul, Baghdad, and Basrah) for the year 2016 showed close agreement between the estimated and measured OLR. Mosul at the north of the Iraq, showed the lowest root mean square error (RMSE) and correlation coefficient (R) ranged between (1.3853 and 4.4966) and (0.9929 and 0.9993), respectively for the two developed models (MLR and ANN) respectively, indicating model's efficiency and accuracy. Statistical analysis in term of β showed that surface temperature (1.823 to 2.311) tended to provide a high contribute to OLR values. These results indicate the advantage of using the AIRS data and both of correlation analysis and computing system to investigate the impact of the meteorological parameters on OLR over the study area.