Microbial fuel cell (MFC) is one among several other technologies which are being vigorously explored on the assumption that they can achieve pollution control with concomitant generation of ‘clean’ energy. In this study, the techno-economical problems associated with MFCs have been identified and catalogued in the context of the fuel cell technology in general and MFCs in particular. It is shown that even as the attention of the supporters of MFCs is riveted on the ability of MFCs to generate electricity directly from organic waste, the high costs and the pollution that the making, operation, decommissioning, and disposal of MFCs entails, is not taken into account. Once this is done, MFCs prove not only prohibitively costly but environmentally incompatible as well. In this respect MFCs are one among numerous other waste-to-wealth technologies whose promise was never fulfilled because the energy they generated might have been clean but the process of that generation was very unclean as well as expensive. The study underscores the harm caused by the expectations associated with MFCs and other similar, perpetually ‘likely to succeed’, technologies because in the vain hope that such options will one day enable ‘clean’ treatment of waste we keep generating ever larger quantities of waste instead of focusing on what is viable: waste reduction and conservation of resources.

The major and overriding factors affecting water quality and the aquatic ecosystems in the coastal areas are sewage and nutrient inputs from municipal and industrial wastewater, depletion of seaside contrivances, risks of public health as well as loss of biodiversity. The coastal area of the Karachi harbour is most heavily polluted due to these reasons. In this study, we proposed the artificial neural network (ANN) models to monitor and control the sea surface water quality of the Karachi coastal area along the harbour. Recently, various types of ANN have been successfully applied in hydrological fields. In this study, Nonlinear Auto Regressive eXogenous Neural Network (NARX-NN) shall be applied to predict the concentration of heavy metals in coastal sea surface water of the Karachi harbour area. This method provides significant insight into the comparative study of two different training functions of NARX-NN, namely, Levenberg-Marquardt (LM) and Scale Conjugate Gradient (SCG). The physical parameters like sea surface temperature (SST), salinity, tides and pH are taken as an input and the chemical parameters chromium, copper, lead, nickel and zinc are taken as output individually for all six locations. The performance of the model was evaluated by statistical criteria that include a correlation coefficient (r) and mean square error (MSE). The prediction results indicated that the LM training function is superior to SCG training function. Hope this study is helpful for local authorities and policy makers to develop a new infrastructure and install a water treatment plant to reduce the water pollution of the harbour area.

Zero-valent iron permeable reactive barrier (ZVI-PRB) has attracted great attention for its high efficiency and low cost in the in-site remediation process. However, passivating oxide layers are usually yielded and covered on the surface of ZVI, which shorten the service life of PRB. In this study, Morganella morganii subsp was used to hydrolyse the passivating oxide layers on ZVI. The hydrolysing condition was optimized. The highest Cr(VI) removal efficiency was achieved with glucose of 4 g/L, yeast powder of 6 g/L and pH = 7. With Morganella morganii subsp, the maximum removal quality of ZVI was increased from 19.96 mg/g to 24.35 mg/g, indicating Morganella morganii subsp could improve the reduction ability of ZVI. SEM-EDS analysis also showed that M. morganii subsp could promote the surface corrosion of ZVI and adsorb Cr simultaneously.

Recycling of organic waste with enormous nutrients gives soil fertility when added to the soil and reduce the usage of chemical fertilizers. Vermicomposting process of recycling the bio-organic waste by earthworms contains efficient nutrients with low levels of toxic contents. In the present study, banana leaves waste was mixed with cow dung in different ratios. The earthworm Eudrillus euginea was later added to the compost. Total organic matter (TOM), total organic carbon (TOC), pH, EC, total alkalinity and phosphorus were analysed and compared for different ratios of vermicompost at different day intervals. Microorganisms present in vermicompost were isolated and analysed for their enzymatic activities. Compost maturity was also observed by FTIR application. Results showed that the vermicompost quality was improved with positive catalase and protease enzymatic activity. FTIR analysis showed the proper maturation of vermicompost with reduced complex structures such as aromatic compounds, polysaccharides and polypeptides. It was concluded that composting of organic wastes by vermicomposting promote humification, increased microbial activity and enzyme production, which in turn increase the aggregate stability of soil particles resulting in better aeration with pollutionfree technique.

Civil buildings are among the structures that consume the most energy in society. Reducing the energy consumption of civil buildings has become an important component of China’s energy policy. Identifying the key influencing factors of the energy consumption of civil buildings and formulating effective energy-saving countermeasures are important to enhance the energy efficiency of civil buildings. This study conducted a systematic analysis of the influencing factors of the energy consumption of civil buildings in Hubei Province, China. First, existing studies on the influencing factors of the energy consumption of buildings in foreign developed countries were reviewed. The status of the population, economic life, and social life that influenced the energy consumption of civil buildings in Hubei Province in the past 10 years was summarized. Relevant influencing factors were estimated via ridge regression. Results demonstrated that developed countries generally investigated the influencing factors of the energy consumption of civil buildings from the energy supply-demand relation, family factors, and out-of-family factors. Gross domestic product (GDP), total population, tertiary industry development, per capita floor space, household consumption level, and urbanization facilitated the energy consumption of civil buildings in Hubei Province during the aforementioned period, and the regression coefficients were significant at the 5% level. Lastly, policy countermeasures were proposed to accelerate the energy-saving development of civil buildings. Research conclusions are important to enrich theories regarding the energy consumption reduction of civil buildings, to help relevant government sectors of Hubei Province recognize action points for the energy-saving development of civil buildings, and to accelerate the benign development of energy-saving buildings.

As a strategic emerging industry, environmental protection industry is important in the development of national economy. However, few empirical studies on the performance of environmental protection industry are carried out. In order to explore development performance and influencing factors of environmental protection industry in China, the selection of development data of China’s 31 provincial regions under the environmental protection industry was conducted based on industrial efficiency, economic contribution, industrial scale, and development speed. Development performance of environmental protection industry was qualitatively analysed and influencing factors were explored by using the method of factor analysis. Results show that the factor score of the eastern region is positive in both industry scale and pollution treatment. Factor score of industry scale, industry contribution and pollution treatment in the central region is positive. Development of environmental protection industry in the western region lags far behind other areas, and only factor score of industry contribution are positive and significantly higher than other areas. Factor score of industrial scale, industrial contribution, and pollution treatment in the northeast region is lower than that in the eastern and central region. Suggestions and countermeasures are proposed to promote the development of the environmental protection industry.

To study the characteristic behaviour of NO2 is quite necessary. Nitrogen dioxide is a major pollutant in the atmosphere, being a precursor to acid rain, photochemical smog, and ozone accumulation. Measurements of NO2 data over a period of one year (October 2014-September 2015) have been used to evaluate the NO2 concentration levels. The frequency distribution of NO2 reveals that out of the total 8760 data points, about 86% of NO2 lies between 5 ppb and 20 ppb. The lowest distribution is found in the range of 0-5 ppb, while the highest lies in the range of 10-15 ppb. The NO2 measurement level has been examined on a diurnal and seasonal scale. The diurnal scale of NO2 shows lesser values during daytime and higher values during night hours. The NO2 concentration levels are high in summer and minimum in the north-east monsoon. The daytime and night-time NO2 concentration pattern is found to be similar to the global scenario. It is observed that the NO2 concentrations in the study area are not high enough to pose health problems. The observed NO2 concentration levels at the study area are well within the National Ambient Air Quality standard for the entire period of study.

Water pollution by heavy metals due to discharge of industrial and anthropogenic waste leads to serious environmental and health problems as most of these heavy metals are carcinogenic in nature. In the present study chromium biosorption capacity of live and dead biomass of bacterial strain HGB1 isolated from Ganga River in Haridwar, which was examined as Bacillus subtilis, following 16S rDNA sequence analysis, was examined for different physical parameters such as pH, time of incubation and temperature. Experimental results indicate that the Bacillius subtilis has maximum tolerance capacity up to 1000 mg.L-1 with highest metal uptake of 95.64%, 97.25% and 97.11% at pH 3, 60 minutes, 2.5 mg/mL biomass respectively in case of dead biomass. In case of living biomass, highest metal uptake was 81.64%, 96.79 % and 95.89% at pH 7, 72hr and 32°C respectively. The surface chemical functional groups of Bacillus subtilis identified by FTIR were amino, carboxyl, hydroxyl and carbonyl groups. The morphological changes were examined by SEM analysis.

Renewable fuels are desirable as alternate fuels with ignition quality equivalent to diesel and its combustion parameters, but unsuitable for direct operation in diesel engines as fuel because of their higher viscosity. Hence, fuel and engine-based modifications are being developed to improve the performance, emission and combustion behaviour of the compression ignition engines. The higher viscosity of fuel oil does not let it vaporize even after it is being injected into the combustion chamber. Therefore, converting the higher viscosity of vegetable oil into biodiesel improves the atomization resulting in better combustion. Issues related to the use of biodiesel as working fuel are its oxidation stability and performance. In this study, safflower oil, neem oil and corn oil are used as fuel oils. The experimental results displayed a significant increase in the brake thermal efficiency of 28.25% for corn oil methyl ester (COME). HC and CO emissions are lower with corn oil methyl ester. At full load, the smoke emission reduces slightly with corn oil methyl ester about 58% opacity respectively, but it is still lower than diesel having 66.2% opacity.

Biochar is thought to be a good adsorption material for the adsorption of heavy metals. In this study, biochar derived from Torreya grandis nutshell was prepared through to be pyrolyzed under oxygen limited conditions in a muffle furnace. The adsorption experiments of Cr(VI) were carried out. Through Elemental Analyzer, Specific Surface Area Meter, Scanning Electron Microscopy, Transmission Electron Microscopy and Fourier Transform Infrared Spectroscopy, a fundamental understanding of the physical and chemical properties of biochar was gained. The results showed that it was a smooth sheet and irregular arrangement structure. The elements of C, H, O and N of biochar are 45.21%, 5.18%, 46.16% and 3.45% respectively. BET specific surface area of biochar is 42.24 m2/g. A lot of oxygencontaining functional groups (– OH, COO –, – C – OH and so on ) appeared on the surface of biochar. It can be described by the pseudo-second order kinetic rate model and Langmuir isotherm model. The adsorption process is a monolayer chemical process. The adsorption mechanism of biochar on heavy metal Cr(VI) contains the electrostatic attraction between biochar and Cr2O7 2-, HCrO4 - and CrO4 2- ions in aqueous solution and complexation reaction of oxygen-containing functional groups (– OH, – COOH and so on) and Cr2O7 2- , HCrO4 - and CrO4 2- ions on the surface of biochar.