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.

6-10

Authors: A. K. Yadav

Day by day the energy consumption is very rapidly increasing. The world’s fossil fuel supply will be depleted in future. The rate of energy consumption is increasing the supply is depleted resulting in inflation and energy shortage. This is called the energy crisis. Alternate or renewable energy resources are very essential to develop for future energy requirement. Biodiesel is the best alternative to petrodiesel. The present research work deals with the production of biodiesel from Kusum oil. Kusum oil methyl ester (KOME) was produced using a two-stage esterification cum transesterification process on account of the high free fatty acid (FFA) contents of the oil. From the above study it may be concluded that Kusum oil is a promising feedstock for biodiesel production and may be the best alternative of petro-diesel The biodiesel property of Kusum oil methyl ester (KOME) has been characterized and it shows that KOME meets the properties of biodiesel as stated in ASTM/EN standards.

18-25

Authors: C. Kurinjimalar, G.Kavitha, S. S. Begum , G. Rajaram, S.Nagaraj, N. Senthilkumar and R. Rengasamy

Biofuel production by a sustainable method using microalgae is entirely dependent on biomass production. However, commercialization at large scale using microalgae is a major obstacle using analytical grade growth nutrients, due to their cost effectiveness. Hence, development of a cost effective method is essential to reduce the production cost. Therefore, the present study envisaged the effect of low-cost commercial fertilizers such as urea, sodium bicarbonate, magnesium sulfate, potash and di-ammonium phosphate as growth nutrients for the production of biomass and total lipid of Botryococcus braunii were made. The biomass and total lipid production were optimized using Response Surface Methodology by 2 5 Central Composite Design. The result showed 225 mg L -1 of urea, 650 mg L -1 of sodium bicarbonate, 225 mg L -1 of magnesium sulfate, 150 mg L -1 of potash and 15 mg L -1 of di-ammonium phosphate supported the algal growth with a maximum biomass and total lipid of 0.792 gL -1 dry wt.. and 260 mg L -1 dry wt.., respectively. The biomass productivity of alga B. brauniiat the above condition recorded as 0.04 gL -1 day -1 with a generation time of 1.90 days.

31-35

Authors: N. Azimi, G.D. Najafpour and M. Sadeghpoor

In this study the performance of integrated fixed film activated sludge system (IFAS) in Amol industrial wastewater treatment plant (Amol, Iran) in treatment of food industrial wastewater was investigated. In addition, kinetic coefficients were evaluated for the system. The capacity of this system was 1700 cubic meters per day; that includes different process comprising physical and biological treatment, disinfection, sludge thickening, digestion and dewatering. COD removal efficiency and kinetic coefficients including yield coefficient (Y), half saturation coefficient (Ks), maximum substrate utilization rate constant (k) and endogenous decay coefficient (kd) were evaluated. The obtained results demonstrated that except Ks other coefficient were in the normal range that was frequently reported for conventional activated sludge in the literature. The COD removal efficiency was about 98 to 99 percent. The results indicated that there is a direct relationship between the variation of kd and Ks with effluent substrate concentration; while, the relationship between rate constant (k) and effluent COD is reversed. Finally, the effect of increasing sludge retention time (SRT) on COD removal was also studied. It was concluded that COD removal increased with an increase active solid retention time to a certain point, behind that point there was no significant changes observed.

44-47

Authors: P. Hartwig

The energy demand of the wastewater treatment is contributing with a significant share to the running costs. Through optimization of the technology and the process control, the specific energy demand can be reduced to < 20 kWh/PE∙year. Only with the technology of anaerobic digestion of the sewage sludge and additional co-substrates a complete covering of the energy demand is possible. The treatment of the additional organic residues in the digester increases the specific gas production, contributes to a good economy of the wastewater treatment and solves at the same time an organic waste problem. As co-substrates a wide range of organic residues are available, like grease, residues from food production (slaughterhouse, fruit juice, diary etc.) and agricultural residues or products. Also the organic fraction of the solid waste is an effective co-substrate after a suitable pre-treatment. For application of this technology for smaller plants, a compact technology with an integrated digester has been developed (H-Batch system). Use of organic solid waste fraction as substrate (DUPLEX-technology) an energetic autarkic operation is possible for wastewater treatment plants larger than around 15,000 PE. This technology can especially been applied where the infrastructure for the waste water treatment and the solid waste treatment has to be developed at the same time.

56-60

Authors: M. A. I. Juel, S. A. Syed and T. K. Dey

Activated sludge process is feasible and extensively method used for biological treatment of sewage and industrial wastewaters. The system is usually designed based on the simplified hydraulic related parameters. But design of biological treatment system based on hydraulic considerations is not reasonable to ensure efficient treatment due to the extensive variation in the composition of wastewater and also for complex nature of biochemical reactions occurring in the treatment processes. Hence kinetic approach can be an option for appropriate design of biological treatment systems rather than hydraulic parameters considerations. The present study is aimed to develop kinetic coefficients for the treatment of chrome-tannery wastewater using activated sludge process. A laboratory-scale treatment unit subsuming an aeration tank and a clarifier were used for this system. The treatment unit was operated continuously for 80 days by varying the hydraulic retention time from 3 to 12 days. BOD for both influent and effluent as well as mixed liquor volatile suspended solid (MLVSS) of aeration tank were determined at different retention time to yield data for kinetic coefficients. The substrate utilization rate coefficient (k) was 0.624 day −1 while the half velocity constant (K S ) was 38.42 mg/L, yield coefficient (Y) was found to be 0.674 mgMLVSS/mgBOD and the endogenous decay coefficient (K d ) was found as 0.068 day -1 . These coefficients can be utilized for the rational design of activated sludge system for the treatment of chrome tannery wastewater.

67-70

Authors: Essien I. E. and Inyang, A.

The exposure level of gamma radiation and its consequent annual dose rate from the blocks faculty of sciences University of Uyo, Nigeria were investigated. An in -situ measurements of the exposure level were conducted using Radex radiation meter model RD 1212. The mean exposure measured for the different locations within the departments ranged between 0.096 ± 0.003 µSv/h µSv/h to 0.140± 0.007 µSv/h and the corresponding calculated annual dose rate (ADR ) ranged between 0.742 ± 0.021 mSv/y to 0.981± 0.049 mSv/y with department of chemistry contributing the highest value. Taking the football field as the reference site, the results show that the presence of chemicals have slightly increased the radiation level in the studied area; but not large enough for being concern as the annual dose rate is below the acceptable dose limit of 1mSv/y for the public and 20mSv/y occupational limit for personnel in the department. The area of study is new hence it is recommended that routine radiation level monitoring should be carried out for possible rise in the radiation level to be observed. For the safety, it is recommended for staff and students should spend less time indoors. The proper application of gamma rays are used for sterilization and cancer therapy.