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Study on an Existing PV/Wind Hybrid System Using Biomass Gasifier for Energy Generation Полный текст
2020
Malik, P. | Awasthi, M. | Sinha, S.
Untapped pine needles with high potential for energy generation in the hilly area are not only a waste of resource but also increase the chance of environmental hazards as forest fires and GHG emission. This study is conducted to propose a new hybrid system (PV/Wind/Biomass) using abundant pine needle resource as a replacement of existing roof-mounted PV/wind hybrid system and analyse the feasibility using Hybrid Optimization of Multiple Energy Resources (HOMER). Biomass gasifier is integrated to meet the increased load demand of 29.5 kW from 4.3 kW at the Centre for Energy and Environment Engineering building in NIT-Hamirpur. Both cases (with and without storage) has been considered in this research study. New optimized configuration is found to be a 1kWp PV array, one wind turbine of capacity 5kW, gasifier with a 17 kW capacity, 10 numbers of 12v batteries connected in series and 10 kW converter. The comparative analysis of off-grid hybrid systems shows that the system with the storage unit was more economical with 0.222 $/kWh as the cost of energy generation compared to the system without storage unit. The proposed hybrid system is found more reliable, economical and environment friendly and save about 27815 kg of CO2 per year when only diesel is used to meet the same energy demand. Therefore, biomass gasifier in decentralized small-scale power plants can be a better replacement for diesel generators.
Показать больше [+] Меньше [-]Sustainable Environmental Management using Life Cycle Sustainability Assessment Model in Petrochemical Industry Полный текст
2020
Maleki, R. | Atabi, F. | Jozi, S. A. | Arjomandi, R. | mansouri, N.
This study aims to present a sustainable environmental model using the life cycle sustainability assessment (LCSA) method in Shazand Petrochemical Company. To determine the evaluation indices, two Delphi and DEMATEL-FTOPSIS questionnaires were distributed among 27 and 8 experts in the field of sustainable environmental management. The environmental, social, economic, environmental-economic, socio-environmental and socio-economic factors were selected as the main criteria based on the previous studies. Data analysis was performed using the DEMATEL-FTOPSIS approach. The values of the determined indices were specified by this study, and the management of the company was prepared. The indicated that the BOD/COD output from the company with the value of 2.181 has the highest effectiveness. Moreover, the index of having short - and long-term planning for local sustainable development with the value of 2.416 had the highest influence. Identification of powerful, strategic and high-quality contractors to enter a long-term contract with them in order to get the competitive advantage in the value chain of the company with the value of 0.569 was found to be the best strategy. Eventually, the sustainable management model for petrochemical industry was presented based on the output results. In this model, indices, prioritizing improvement plans and assessing life cycle sustainability were identified as the most important factors among others.
Показать больше [+] Меньше [-]Artificial Neural Network Modeling for the Management of Oil Slick Transport in the Marine Environments Полный текст
2020
Janati, M. | Kolahdoozan, M. | Imanian, H.
Due to an increase in demand of petroleum products which are transported by vessels or exported by pipelines, oil spill management becomes a controversial issue in coastal environment safety as well as making serious financial problems. After spilling oil in the water body, oil spreads as a thin layer on the water surface. Currents, waves and wind are the main causes of oil slick transport. These phenomena depend on the overall interaction among gravity, viscosity, surface tension and interfacial tension of oil in water bodies. In the current study, Artificial Neural Network (ANN) models have been designed and trained for the prediction of oil spreading and advection under different hydrodynamic conditions. In this regard, results obtained from a multiphase Lagrangian numerical model are deployed to train ANN model. The mentioned numerical model which is based on the moving particle semi-implicit (MPS) method is developed in the earlier stage of the study. In this research study, the MPS numerical model is first validated and verified against the analytical formulas which are based on experimental data cited in the literature. Then, various hydrodynamic conditions and oil spill scenarios were chosen to obtain different numerical model results. Finally, numerical model results are then deployed for training ANN model to provide a useful tool for urgent prediction of oil slick trajectory in order to manage the oil slick transport in the coastal environments.
Показать больше [+] Меньше [-]Estimation of Phosphorus Reduction from Wastewater by Artificial Neural Network, Random Forest and M5P Model Tree Approaches Полный текст
2020
Kumar, S. | Deswal, S.
This study aims to examine the ability of free floating aquatic plants to remove phosphorus and to predict the reduction of phosphorus from rice mill wastewater using soft computing techniques. A mesocosm study was conducted at the mill premises under normal conditions, and reliable results were obtained. Four aquatic plants, namely water hyacinth, water lettuce, salvinia, and duckweed were used for this study. The growth of all the plants was inhibited in rice mill wastewater due to low pH, high chemical oxygen demand, high conductivity, and high phosphorus concentration. Subsequently, a 1:1 ratio of mill water to tap water was used. A control was maintained to assess the aquatic plant technology. In this study, the aquatic plants reduced the total phosphorus content up to 80 % within 15 days. A comparison between three modeling techniques e.g. Artificial neural network (ANN), Random forest (RF) and M5P has been done considering the reduction rate of total phosphorus as predicted variable. In this paper, the data set has been divided in two parts, 70 % is used to train the model and residual 30 % is used for testing of the model. Artificial neural network shows promising results as compared to random forest and M5P tree modelling. The root mean square error (RMSE) for all the three models is observed as 0.0162, 0.0204 and 0.0492 for ANN, RF and M5P tree, respectively.
Показать больше [+] Меньше [-]Phytotoxicity of Lead and Chromium on Germination, Seedling Establishment and Metal Uptake by Kenaf and Mesta Полный текст
2020
Sultana, R. | Islam, S. M. N. | Zaman, M. W. | Uddin, N.
Heavy metal contaminated soil raises major global environmental and agricultural concern. Recently soil pollution through lead (Pb) and chromium (Cr) becoming serious problem and remediation or utilization of those contaminated soil with potential crops is of the outmost importance. The objectives of present study were to examine the effects of Pb and Cr on three different kenaf and mesta varieties for seed germination, seedling establishment and amount of Pb and Cr uptake by tested varieties in laboratory condition. Three varieties were used for the study namely, HC-95 (kenaf), CPL-72126 (mesta) and Samu-93 (mesta) and the treatments were combination of Pb and Cr chemical at (0,0), (60,60), (80,80), (100,100) and (120,120) mg/L. Increased level of lead and chromium gradually reduced the germination percentage and primary growth parameters compared to control. The shoot and root lengths were affected only little, whereas, the biomass showed a considerable reduction with the increase of Pb and Cr toxicity. Stress tolerance indices showed a gradual and negative response by the plant with the increase of metal concentrations. However, in all the levels of Pb and Cr treatment, the seedlings were capable to tolerate the toxicity and seedlings were established. Bioaccumulation of Cr was higher than that of Pb in all varieties and in all treatments. The interaction of Pb and Cr reduced the toxic effect of both metals to the plants. The findings are helpful for selecting fiber crop varieties for cultivation in contaminated soils or phytoremediation of Pb and Cr from the contaminated soils.
Показать больше [+] Меньше [-]Carcinogen Risk Assessment of Mutagen X in Chlorinated Drinking Water in West of Tehran, Using Probabilistic Approaches Полный текст
2020
Bagheban, M. | Karyab, H. | Baghdadi, M. | Mohammadi, A. | Akbarpour, B. | Keshtkar, A.
The present study aims at evaluating the risk of Mutagen X (MX) (3-chloro-4-(dichloromethyl)-5-hydroxy-2 (5H)-furanone) and adverse health effects, associated with direct ingestion of chlorinated drinking water in west of Tehran, supplied by chlorinated drinking water from surface and underground water sources. For one year, MX concentrations in tap water samples has been measured for consumers in four different zones in western Tehran. It has been found that average MX concentration in the whole study area is 24.16 ng/L, with the highest concentration being in Zone 1 with a value of 38 ng/L. Also, the role of water sources, seasonal changes, and effective factors such as Total Organic Carbon (TOC) have been evaluated on MX formation. The highest of excess lifetime cancer risk (ELCR), estimated as 0.0037E-05, belongs to Zone 1, which uses surface water to supply drinking water, while the lowest can be seen in Zone 4, being 0.0021E-05. This latter zone utilizes underground water as the water source. In all zones, the highest risk of excessive cancer is related to winter, ranging from 0.0045E-5 in Zone 1 to 0.0023E-5 in Zone 4. The estimated number of cancer cases for Zones 1 to 4 have been 0.012, 0.016, 0.016, and 0.004, respectively, based on their population. The estimated average risk and the number of ELCR, caused by exposure to MX, through direct ingestion of drinking water have been 0.0030E-5 and 0.047, respectively, in the entire studied area for the duration of one year.
Показать больше [+] Меньше [-]Decolorization of Reactive Black-5 High Concentration by Vermicompost Microflora and Detoxification of By-Products by UV-C/H2O2 Post-Treatment Полный текст
2020
Emadi, Z. | Sadeghi, M. | Mohammadi-moghadam, F. | Sadeghi, R. | Forouzandeh, S. | Sadeghi, R.
The presence of synthetic dyes in textile wastewater is a problematic issue for environmentalist. Nowadays, dye removal is practiced via different methods. Among all these methods, biodecolorization is an ideal technique. The present research apples vermicompost microflora to remove reactive black- C, pH = 7, and under anaerobic condition. At 36h, removal efficiencies of 94.79%, 94.06%, and 93.6% are obtained for concentrations of 800, 850, and 950 mg/ L, respectively. It has also been observed that when the initial concentration rises to 1400 mg/ L, the efficiency drops to 51.57% at 36h. Also, methyl red, methyl orange, eriochrome black-t, and acid blue-113 could be decolorized by the isolated bacterial strain with an efficiency of 94.29%, 92.10%, 90.83%, and 88.95%, respectively. Phytotoxicity Test shows that the parent form of reactive black-5 has not been toxic for the seeds (100% germination for Triticum aestivum and 90% for Maize). When reactive black-5 is treated with isolated bacterial strain under anaerobic condition, none of the seeds remain germinated which might be due to the possible formation of toxic aromatic amines intermediates. Therefore, ultraviolet C + 100 mM H2O2 has been used as the post-treatment process for detoxifying of by-products. After the integrated treatment of synthetic wastewater, containing RB-5, complete germination (100%) of Triticum aestivum and Maize is observed. In the post-treatment process, due to the generation and activation of hydroxyl radicals, the toxic aromatic amines compounds convert to the less toxic compounds.
Показать больше [+] Меньше [-]Assessment of Disposal Scenarios for Solid Waste Management Using Fuzzy Rapid Impact Assessment Matrix; a Case Study of Khorramabad Industrial Estate Полный текст
2020
Ghobadi, M. | Ahmadipari, M. | Pazoki, M.
The present paper tries to assess different scenarios for solid waste management in Khorramabad industrial park. It uses a new hybrid method of fuzzy Rapid Impact Assessment Matrix, and proposes the Fuzzy theory, the ranking method of which is innovated so that the accuracy and flexibility of the RIAM method could be improved. Four scenarios are studied, namely open dumping, sanitary landfill, gasification, and incineration. They are then evaluated in terms of their physical/chemical, biological/ecological, social/cultural, and economic/operational effects. Afterwards, two scenarios have been selected with the aim of energy production. The evaluation of these aspects for each scenario is in accordance to the expert's judgments and field study, with the results showing that sanitary landfill has had the least undesirable effects. Hence, this approach is selected as the best scenario for waste management in the studied area. According to the obtained results, it is suggested to consider sanitary landfills as the main part of the waste management hierarchy program of the studied area. Also, it is highly recommended to use the Fuzzy RIAM technique in similar studies and to compare the results with the new ones in order to examine the accuracy of the new improved method.
Показать больше [+] Меньше [-]Levels of Fine Particulate Matter Bound Trace Metals in Air of Glass Industrial Area; Firozabad Полный текст
2020
Rajouriya, K. | Rohra, H. | Taneja, A.
The present study deals with sequential extraction of fine particulate matter (PM2.5) bound trace metals in an industrial area of Firozabad, India. During the study period, daily PM2.5 concentration ranged between 73.49 μg/m3 and 113.26 μg/m3 with poor air quality index of 196.37. In the present study, Ca recorded the highest while Co had the lowest concentration among all analysed metals. Mn, Ni, Pb, Co, and Cu had high bioavailability (34.80%-65.80%) than other elements. Cd, Pb, and Cu were found to be highly enriched (EF> 289-6516) by varied anthropogenic activities. Hazard Quotient (HQ) for Ni, Mn, and Cr and Excess Lifetime Cancer Risk (ELCR) of Cr(VI) and Ni exceeded the respective safer limit (HQ>1 and ELCR≥ 10-6), thus implying serious risk to the receptors. All the metals had the highest concentration in less mobile and residual fraction except for Ni and Co, which inferred greater risk due to their high toxicity. Overall, the results present exposure and risk assessment of metal associated particles; that provides in-depth knowledge of the risk factors through inhalation exposure pathway of particles associated with industrial environment.
Показать больше [+] Меньше [-]Air Pollution in the Capital City of Bangladesh: Its Causes and Impacts on Human Health Полный текст
2020
Khuda, K. E.
Air is one of the precious natural resources that are essential for animal including the human being. It is also the most important gift of nature without which human cannot survive. Pollution in the urban areas like Cairo, Delhi, Mexico and Dhaka far surpasses the acceptable limits set by the World Health Organization (WHO). Urban air pollution in the South Asian region is approximated to cause more than 300,000 deaths and billions of cases of respiratory disease per year. In Bangladesh, about 200000 people die each year due to the air pollution as the WHO estimates in 2018. The air in Dhaka City, the capital of Bangladesh, has become worsen to a level that the city has been identified as one of the most polluted cities in the world. Taking the problem with utmost importance into consideration as it is related with the public health, air pollution is being treated as one of the priority issues. The level of pollution at roadside environment is deeply connected with the density of motor vehicles plying on the roads. This situation is expected to worsen further in the upcoming days due to the increasing number of motor vehicles resulted from rapid economic growth and industrialization. This paper aims to provide the present statues of the air pollution in Dhaka city and some specific recommendations for making the city as a better living place through reducing its air pollution.
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