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Underground gassy longwall mining goafs may suffer potential gas explosions during the mining process because of the irregularity of gas emissions in the goaf and poor ventilation of the working face, which are risks difficult to control. In this work, the 3235 working face of the Xutuan Colliery in Suzhou City, China, was researched as a case study. The effects of air quantity and gas emission on the three-dimensional distribution of oxygen and methane concentration in the longwall goaf were studied. Based on the revised Coward’s triangle and linear coupling region formula, the coupled methane-oxygen explosive hazard zones (CEHZs) were drawn. Furthermore, a simple practical index was proposed to quantitatively determine the gas explosion risk in the longwall goaf. The results showed that the CEHZs mainly focus on the intake side where the risk of gas explosion is greatest. The CEHZ is reduced with increasing air quantity. Moreover, the higher the gas emission, the larger the CEHZ, which moves towards the intake side at low goaf heights and shifts to the deeper parts of the goaf at high heights. In addition, the risk of gas explosion is reduced as air quantities increase, but when gas emissions increase to a higher level (greater than 50 m3/min), the volume of the CEHZ does not decrease with the increase of air quantity, and the risk of gas explosion no longer shows a linear downward trend. This study is of significance as it seeks to reduce gas explosion accidents and improve mine production safety.

This study aims to analyze whether exposure to indoor air pollution affects obesity. In our research, we recruited 127 participants, with an average age of 43.30 ± 15.38 years old, residing in 60 households. We monitored indoor air quality for 24 h, and conducted both questionnaire surveys and collected serum samples for analysis, to assess the relationship between indoor air pollutant exposure and obesity. After adjusting for demographic characteristics, the results showed that CO2 exposure is positively associated with being overweight and with a higher risk of being abdominally obese. Exposures to CO and formaldehyde were also positively associated with being overweight. IQR increase in TVOC was positively associated with increases in the risk of a high BMI, being abdominally obese and having a high body fat percentage. Two-pollutant models demonstrate that TVOCs presented the strongest risks associated with overweightness. We concluded that persistent exposure to indoor gaseous pollutants increases the risk of overweightness and obesity, as indicated by the positive association with BMI, abdominal obesity, and percentage body fat. TVOCs display the strongest contribution to obesity.

The calculation method commonly used in the industry takes into consideration mainly fuel consumption (excluding electricity) and the amount of removed moisture which is reflected in the unit MJ·(Mg·%)−1. This is not a scientific approach because the result will change if the basic moisture is different (drying from 21% to 18% will consume less energy than drying from 18% to 15%). This paper aims to compare the energy consumption of two industrial continuous flow grain dryers powered by LPG and hard coal based on a comprehensive approach to energy efficiency calculation enriched with electricity consumption, flow measurements, and control of grain moisture. It could be useful for manufacturers who could use this method to generate more reliable data in their product datasheets, and it could also be legally regulated as an appropriate tool for calculating the energy consumption of agricultural grain dryers. According to the approach presented in this paper, the S428.CS construction powered by LPG gas had an energy consumption that was 6.14% lower than the DT2532 dryer construction, which used hard coal.

The abnormal emission of gas in coals is the main factor that induces serious gas disasters in coal mines. During the coal mining process, roof movement has important effects on the gas emission law and gas flow characteristics. In this study, an extremely thick coal seam under fully mechanized sublevel caving mining conditions from the Tashan coal mine in China was used as an example; the effect of roof weighting on gas emission in the goaf was studied. Then, the large roof weighting step and the small roof weighting step caused by the different thicknesses of lamprophyre breakage were used as the objects and a numerical simulation study on the gas flow characteristics in the goaf was carried out. The results indicate that the mining coal seams, the overlying adjacent unmined coal seams, and the goaf are the main contributors to the large gas emission capacity, and even situations exist where the gas concentration exceeds the limit in the working face. During roof weighting, the gas concentration and emission capacity in the return airway, upper corner, and high drainage roadway increase substantially. The results of the numerical analysis are in good agreement with the observed data, which indicates that it is effective to control the gas in coal seams by designing the location of high drainage roadway according to the mining characteristics of coal seam and the gas emission law.

Today, in various leading power utilities in developing countries, achieving optimal operational energy management and planning, taking into account the costs reduction of generation, transmission and distribution of electricity, and also reducing the emission of an environmental pollutant becomes more and more important. Optimal use of renewable energy sources (RESs) is an effective way to achieve these goals. In this regard, in this research article, an improved multi-objective differential evolutionary (IMODE) optimization algorithm is suggested and performed to dispatch electricity generations in a smart microgrid (MG) system, taking into account economy and emission as competitive issues. In this paper, a nonlinear equation of multi-objective optimization issue with various equality and inequality limitations is formulated in order to lower the total operational costs of the MG considering environmental pollution effects simultaneously. In order to address the issue of optimal operation of the MG in single-objective and multi-objective forms, an intelligent method according to the improved differential evolutionary (IDE) optimization is utilized and performed and the proposed algorithm is implemented on different problems. First, it is assumed that there is no limit to the exchange of power overhead, and secondly, the limitation of power exchange with the upstream grid is considered. In multi-objective mode, these two modes are also considered. In order to show the impact of renewable energy on the cost, in the third part of the simulations, the operation is solved with maximum participation of renewable energy sources. In the final section, the sensitivity analysis on the number of populations in this problem is performed. The obtained results of the simulation are compared to differential evolutionary (DE) and particle swarm optimization (PSO) techniques. The effectiveness of the suggested multi-operational energy management method is confirmed by applying a study case system.

Currently, the design of advanced moving grate (AMG) incinerators for solid waste is aided by computational simulations. The simulation approach couples a waste bed model to characterize the incineration processes of the waste material on top of the moving grate, with a computational fluid dynamics (CFD) model to reproduce the heated air movement and reactions in the incinerator space above. However, the simulation results of AMG incinerators are rarely compared with actual field measurements for validation in the literature so far. In this study, we first examine the sensitivity of pyrolysis kinetics in the waste bed model using three existing alternatives. The predictions of combustion characteristics, including the bed height, flow and temperature distributions, composition of stack gases and gas emissions are obtained for the three alternatives and compared with measurements from a simple laboratory furnace. The results show that the pyrolysis kinetics mechanism can significantly affect the outputs from the waste bed model for incineration modelling. Subsequently, we propose a new coupling approach based on a recent AMG waste bed model (which includes the complex pyrolysis kinetics inside the waste bed on top of the moving grate) and the freeboard CFD simulations. The new approach is then used to predict the field performance of a large scale waste-to-energy (WTE) plant and the predictions are compared directly with the real measurements in various operational scenarios. The comparison shows an overall satisfactory agreement in terms of temperature and exit gases composition given the complexity of the real life operations, although the CO emission is slightly underpredicted. National Environmental Agency (NEA) National Research Foundation (NRF) Published version This research was funded by the National Research Foundation, Prime Minister’s Office, Singapore and the National Environment Agency, Ministry of Sustainability and the Environment, Singapore under the Waste-to-Energy Competitive Research Programme (WTE CRP 1601 105). We would also like to acknowledge the support of Keppel Seghers Pte Ltd. who provided the field data for this research project.

The increasing trends in gas emissions have had direct adverse impacts on human health and ecological habitats in the world. A variety of technologies have been deployed to mitigate the release of such gases, including CO2, CO, SO2, H2S, NOx and H2. This special issue on gas-capture processes collects 25 review and research papers on the applications of novel techniques, processes, and theories in gas capture and removal.

Biomass materials have been increasingly used due to their renewable nature. The problems occurring during the storage of fresh woody materials include gas emissions and dry matter losses as a result of degradation. The objective of this study was to investigate and quantify the effect of moisture content on gas emissions from stored wood chips. Experiments were conducted under non-aerobic and aerobic conditions using fresh Western Red Cedar (WRC) chips with different initial moisture contents over a range of temperatures. The peak CO2 emission factor of 2.9 g/kg dry matter (DM) was observed from high moisture chips at 20 °C under non-aerobic conditions after two-month storage, which was an order of magnitude greater than that from low moisture chips. In the case of volatile organic compounds, a range of compounds were detected from all tests. The concentration of VOCs was found to be positively correlated with moisture content. Gas emissions from the aerobic reactors exhibited similar trends as non-aerobic reactors with respect to the effect of moisture content, although higher values were observed under aerobic conditions. Slight reduction of dry mass from all tests at the end of storage indicated the decay-resistance characteristics of WRC.

Utilization of natural resources in the form of coal mines has a positive impact on economic and energy development, in addition to coal mining activities have a negative impact on the environment that result in environmental pollution in soil, water, and air. Pollution begins when clearing land, taking exploitation, transporting, stockpile and when the coal is burned. When land clearing causes damage to forest ecosystems. At the time of exploitation impact on air pollution by coal dust particles, the erosion, siltation of the river, the pollution of heavy metals and the formation of acid mine drainage (AMD). The high acid conditions cause the faster heavy metals such as Hg, Cd, Pb, Cr, Cu, Zn and Ni present in the coal dissolved and carried to the waters. Coal stockpile activity also causes pollution in the air, soil, and water. At the time the coal is burned as an energy source causes the emission of hazardous materials into the air of Hg, As, Se and CO 2 gas, NOx, SO 2 . This condition has an impact on the environment and ultimately on human health. Keywords: coal, pollution, heavy metal, gas emission Abstrak (Indonesian) Pemanfaatan sumber daya alam berupa tambang batubara berdampak positif dalam pembangunan perekonomian dan energi, disamping itu aktivitas penambangan batubara berdampak negatif bagi lingkungan yang berakibat pencemaran lingkungan di tanah, air dan udara. Pencemaran dimulai ketika membuka lahan, pengambilan batubara (exploitasi), pengangkutan, penyimpanan sementara (stockpile) dan saat batubara tersebut dibakar. Ketika pembukaan lahan untuk penambangan batubara, hutan mulai di tebang sehingga menyebabkan kerusakan ekosisitem. Pada saat exploitasi berdampak pada tercemarnya udara oleh partikel debu batubara, terjadinya erosi, pendangkalan sungai, pencemaran logam-logam berat dan terbentuknya air asam tambang (AAT). kondisi asam yang tinggi menyebabkan semakin cepat logam-logam berat seperti Hg, Cd, Pb, Cr, Cu, Zn dan Ni yang ada pada batubara tersebut terlarut dan terbawa ke perairan. Aktivitas penyimpanan sementara (stockpile) batubara juga menyebabkan terjadinya pencemaran di udara, tanah dan air. Pada saat batubara tersebut dibakar sebagai sumber energi menyebabkan emisi bahan berbahaya ke udara berupa Hg, As, Se dan gas CO 2 , NOx, SO 2 . Kondisi ini yang berdampak pada lingkungan dan akhirnya pada kesehatan manusia. Katakunci : batubara, polusi, logam berat, emisi gas.

The further development of coal mining in different countries and in India is connected with many problems. The emission of gas, sudden outbursts of gas and coal, mine fires, dustiness, spontaneous combustion, methane concentration are very serious problems. This article deals with solving these problems. It describes a new method applied in coal mines in the Czech Republic that has brought very good results. Napredak u pridobivanju ugljena u mnogim je zemljama, posebice u Indiji, suočen s brojnim problemima. Postoje velike emisije plinova, njihove iznenadne eksplozije, požari, prašina, samozapaljenje te visoke koncentracije metana. U radu je opisano kako smanjiti ili ukloniti takve probleme, a prikazana je i nova metoda, već primijenjena u češkim rudnicima ugljena, koja je pokazala vrlo dobre rezultate. Web of Science 33 1 13 7

The rapid increase of the number of motor vehicles, especially motorcycles, makes serious problem caused by the pollution from gas emission of fossil fuel combustion. The problems related to human health and the erosion on ozone layer is credited to its gas emission. Several dangerous and toxic gasses such as Hydrocarbon (HC), Carbon Monoxide (CO), and Nitrogen Oxide (NOx), Sulphur Dioxide (SO2), and Lead (Pb) are emitted during IC engine operation.To manage those dangerous gasses, catalytic converter which converts the gasses into more eco-friendly CO2H2O and N2 may be employed. In this research, a specially designed catalytic converter made from brass (CuZn) wire in the form of spider web pattern was fitted into exhaust system of a standard motorcycle. The performance of the converter for several engine rotation speeds was examined by measuring CO and HC of exhaust by using Gas Analyzer.By comparing the exhaust of a standard exhaust system and modified exhaust system (fitted with converter), it can be concluded that the converter was able to decrease the exhaust emission gas. For HC content, the percentage of decrease was as much as 36,88 % for converter fitted exhaust system compared to 61.12% for standard one. For CO content, the decrease percentage was 19.90% compared to 80.10% for standard one.

Besides the application of the life cycle assessment methodology in products and services, the consideration of environmental impacts at the organizational level in a holistic approach can also provide significant information about other environmental issues. In 2012 the European Commission developed the Organizational Environmental Footprint Guide, however there is still scarce experience with its implementation. In this research it was examined whether the conduct of an Organizational Environmental Footprint could be readily applied to construction companies, and additionally the corresponding costs and benefits were estimated. Using a case study within the former Bilfinger Construction Company, part of the Implenia Group since summer 2015, the feasibility of the application of the guide in construction companies was reviewed and possible adjustments were proposed. The main obstacle lies in the product portfolio of such companies, which can be very heterogeneous. It was observed that most data could be collected from the already implemented accounting and procurement software. Additional data were obtained through the environmental management system of the analyzed company. Difficult was the determination of resource use and emissions from upstream activities along the supply chain. Using the Greenhouse Gas Protocol, decision supports were set to generate emissions data. The results of the case study were then generalized to construction companies, what can support such organizations to achieve a sustainable transition to a cleaner production.

One of our era's greatest scourges is air pollution, on account not only of its impact on climate change but also its impact on public and individual health due to increasing morbidity and mortality. There are many pollutants that are major factors in disease in humans. Among them, Particulate Matter (PM), particles of variable but very small diameter, penetrate the respiratory system via inhalation, causing respiratory and cardiovascular diseases, reproductive and central nervous system dysfunctions, and cancer. Despite the fact that ozone in the stratosphere plays a protective role against ultraviolet irradiation, it is harmful when in high concentration at ground level, also affecting the respiratory and cardiovascular system. Furthermore, nitrogen oxide, sulfur dioxide, Volatile Organic Compounds (VOCs), dioxins, and polycyclic aromatic hydrocarbons (PAHs) are all considered air pollutants that are harmful to humans. Carbon monoxide can even provoke direct poisoning when breathed in at high levels. Heavy metals such as lead, when absorbed into the human body, can lead to direct poisoning or chronic intoxication, depending on exposure. Diseases occurring from the aforementioned substances include principally respiratory problems such as Chronic Obstructive Pulmonary Disease (COPD), asthma, bronchiolitis, and also lung cancer, cardiovascular events, central nervous system dysfunctions, and cutaneous diseases. Last but not least, climate change resulting from environmental pollution affects the geographical distribution of many infectious diseases, as do natural disasters. The only way to tackle this problem is through public awareness coupled with a multidisciplinary approach by scientific experts; national and international organizations must address the emergence of this threat and propose sustainable solutions.

Tectonic coal is a kind of soft coal that is generated during tectonic movement. Gas outbursts usually occur in seams containing both virgin coal and tectonic coal. To reveal the adsorption characteristics of this type of coal seam (containing both virgin coal and tectonic coal), both tectonic coal and virgin coal were collected from the same longwall face and a series of laboratory tests were conducted, including coal sorption tests and pore specific surface measurements. Both the tectonic coal and virgin coal were crushed into coal powder (0.18–0.25 mm) for the coal sorption tests. In these laboratory tests, different mass ratios between tectonic coal and virgin coal were tested. We found that with the increase of the percentage of tectonic coal, the adsorption volume showed a rising trend, reached its maximum value, and then decreased. The specific surface areas of the mixed coal samples had the same evolution trends as those of the adsorption volume. From the laboratory tests, we found that when the mass ratio of virgin coal to tectonic coal was 1:1, both the adsorption volume and the specific surface areas reached their maximum values. Due to the percentage variation of the tectonic coal in the panel with the advancement of the longwall face, when the tectonic coal accounted for 50% of the total coal, the gas content would rise. Thus, proper measures should be adopted for outburst hazards control. The mathematical model between the change of specific surface area and the stress and strain of pore expansion before and after gas adsorption was established, and the relationship between the change of pore structure and gas emission before and after gas adsorption was obtained. It provides a theoretical basis for further research on coal and gas outburst mechanisms.

Most of the world’s 1500 active volcanoes are not instrumentally monitored, resulting in deadly eruptions which can occur without observation of precursory activity. The new Sentinel missions are now providing freely available imagery with unprecedented spatial and temporal resolutions, with payloads allowing for a comprehensive monitoring of volcanic hazards. We here present the volcano monitoring platform MOUNTS (Monitoring Unrest from Space), which aims for global monitoring, using multisensor satellite-based imagery (Sentinel-1 Synthetic Aperture Radar SAR, Sentinel-2 Short-Wave InfraRed SWIR, Sentinel-5P TROPOMI), ground-based seismic data (GEOFON and USGS global earthquake catalogues), and artificial intelligence (AI) to assist monitoring tasks. It provides near-real-time access to surface deformation, heat anomalies, SO2 gas emissions, and local seismicity at a number of volcanoes around the globe, providing support to both scientific and operational communities for volcanic risk assessment. Results are visualized on an open-access website where both geocoded images and time series of relevant parameters are provided, allowing for a comprehensive understanding of the temporal evolution of volcanic activity and eruptive products. We further demonstrate that AI can play a key role in such monitoring frameworks. Here we design and train a Convolutional Neural Network (CNN) on synthetically generated interferograms, to operationally detect strong deformation (e.g., related to dyke intrusions), in the real interferograms produced by MOUNTS. The utility of this interdisciplinary approach is illustrated through a number of recent eruptions (Erta Ale 2017, Fuego 2018, Kilauea 2018, Anak Krakatau 2018, Ambrym 2018, and Piton de la Fournaise 2018−2019). We show how exploiting multiple sensors allows for assessment of a variety of volcanic processes in various climatic settings, ranging from subsurface magma intrusion, to surface eruptive deposit emplacement, pre/syn-eruptive morphological changes, and gas propagation into the atmosphere. The data processed by MOUNTS is providing insights into eruptive precursors and eruptive dynamics of these volcanoes, and is sharpening our understanding of how the integration of multiparametric datasets can help better monitor volcanic hazards.

In the last decades, saving energy and protecting environment became the most important topics for search and survey. The energy engineer for any chemical process is obliged by restrictions of “Kyoto Protocol” for limitation of carbon dioxide emissions from fuel combustion, so he does his best to reduce utility consumption and thus reduce gas emission. Proper designing of the heat exchanger network (HEN) for any process is an effective and successful method to minimize utility consumption and therefore minimize gas emission (mainly carbon gases (CO 2 ) and sulfur gases (SO x )). Fuel switching coupled with energy targeting achieved the least gas emission. In this work we choose a hydrotreater unit of a petroleum refinery as a case study due to its effective role and its obvious consumption of utility. We applied the methodology of energy targeting through HEN design (using pinch technology) at several values of mean temperature difference (Δ T min ); where the maximum percentage of energy saving was 37% for hot and cold utility which directly leads to percentage reduction of gas emission by 29% for CO 2 and 17% for SO x . Switching fuel oil to other types of fuel realized gas emission reduction percentage where the maximum reduction established was through natural gas fuel type and reached 54% for CO 2 and 90% for SO x . Comparison between existing design and the optimum Δ T min HEN led to few modifications with the least added capital cost for the hydrotreater existing design to revamp it through four scenarios; the first one depended on fuel switching to natural gas while the second one switched fuel to diesel oil, in the third scenario we applied heat integration only and the fourth one used both of heat integration and fuel switching in a parallel way.

Background and aims The use of summer cover crops (SCCs) as residue inputs in agricultural systems can lead to a potential environmental trade-off between the amount C and N retained and the emission of N as the potent greenhouse gas, nitrous oxide (N2O). Our objectives were to relate N2O fluxes to the quality of SCCs residues and to select SCCs species with high C and N addition and low N2O emissions.Methods We measured SCC biomass production and N2O fluxes after SCCs termination - velvet bean, pearl millet, dwarf pigeonpea, sunn hemp, showy rattlebox and jack bean - under subtropical no-till conditions.Results The N2O fluxes in the first 30 days after SCCs termination corresponded to 65% of cumulative N2O emissions measured during 165 days in 2010 and 150 days in 2011. The cumulative N2O emissions varied from 0.46 to 1.38 kg N ha(-1) and were not proportional to aboveground biomass N addition. Cumulative N2O emissions were positively correlated to water-soluble C and N and the N content of crop residues and negatively correlated to cellulose and hemicellulose content. The N2O emission factor values varied from 0.24 to 0.64% and did not differ among SCCs.Conclusions Sunn hemp and dwarf pigeonpea are the most suitable species for inclusion in crop systems because they combined high C and N input and low N2O emissions.

The article deals with very topical problems as nowadays environment protection is very actual and one of the most obvious areas is freight transport, because it is an important creator of greenhouse gas and environment pollution. Countries face to big public pressure to decrease negative ecological but also economical and social impacts of freight transport. The aim of the article is also showing how to deal with improving of environmental performance of freight transport as there are many ways how to reduce carbon dioxide (CO2) in international road and rail freight transport. Generally actions could be divided to technical and non-technical measures.

In order to accurately predicting gas emission in coal mines, the complicated nonlinear characteristics of gas emission was analysis, the prediction method was put forward for gas emission based on self-organizing data mining. It was used the ternary quadratic polynomial for the local function and the original variable was used in each generation, and the minimum deviation principle was used for criteria of model selected. And then, the high-order equation of prediction was established for gas emission by self-organizing data mining method. The fitness relative error of this prediction model was ±0.03% and predictive relative error was ±1.45% to gas emission in coal mine. The results show that: self-organizing data mining method can automatically analyze non-linear relation between the gas emission and the factors, and can be establish the explicit high order equation to descript the gas emission laws, and the prediction model has enough prediction accuracy for application of actual engineering in coal mines.

For the purpose of making effective analysis and full use of gas measuring data in mines to achieve more accurate gas emission quantity prediction, studied the method for gas emission time series analysis to achieve gas emission quantity prediction based on the Gaussian process regression model. Two methods for gas emission time series analysis were proposed, the relationship between gas emission quantity and time (Q-T) model and autoregression model, considered gas emission time series as a function of time in Q-T model, while constructed the Gaussian process regression model from gas emission time series itself completely in autoregression model. The results of case study show that Gaussian process model can describe the objective laws and the developing trends of mine gas emission, its predictive results are accurate and reliable, therefore, the application of the Gaussian process regression in gas emission time series analysis is a feasible and effective method for gas emission quantity prediction, it has high practical application value.

According to the geological exploration about gas information in Liuzhuang Coal Mine, the gas pressure during well construction parameters, and the actual gas emission from tailgate and track trough, the author calculated and got the gas content of the first coal face; combining with coal mining conditions and coal bed methane occurrence conditions, the authors selected the gas emission coefficient from rock k 1 , the gas emission coefficient from pre-drainage tunnel k 2 , the gas emission coefficient from residual coal k 3 and a series of other forecast parameters, and used sub-source prediction method to calculate the gas emission from mechanized mining face and the adjacent layer. Finally, the author got the total gas emission about the first coal mining face in the 11-2 coal seam in Liuzhuang Coal Mine, which provides a theoretical basis for the gas control in Liuzhuang Coal Mine.

Underground coal mining needs effective technical methods for the control of gas emissions in order to be able to work under safe conditions. Based on the coal seam geological conditions among the Xuan Gang region, a major part of theoretical research and technical development has been directed to this purpose. According to the roles of mining fractures development and relief gas flow, a novel method for the comprehensive gas drainage was proposed and engineering practiced in the mining field, which includes long drilling boreholes, oblique crossed boreholes and upper corner flexible drainage pipelines. Compared with previous gas control measurements, the total gas drainage ratio significantly enhanced from 30% to 67.33% (No.51109 working face) and 76.44% (No.51105 working face). The ventilation air methane concentration of working face greatly decreased down to about 0.3%. Field tests shows that it is an effective method for gas control, which ensured the safety production of underground coal mine. The proposed gas drainage technology provides a novel approach for the three-soft coal seam gas management in China.

14211 was a prepared mining-face in Xin’ an Coalmine, Henan province, and it has not been done any work for mining so far. Geological parameters selected in this paper include seam thickness, burial depth, sandstone ratios in 20m and 40m coal seam roof, gas content and minor faults. With the calculating results of gas emission from 2007 to 2010 in other working faces, this paper interpreted the influence on gas emission of selected geological parameters. The gas emission was combined with characters of micro-cracks, permeability and isothermal adsorption. The results demonstrated that, in 14211 preparing face, there is a negative correlation between the absolute gas emission and 20m-sandstone ratio, while a significant positive correlation between the absolute gas emission and the 40m- sandstone ratio. There is gas conductivity in 20m-sandstone, adjacent to the coal seam roof. And this effect becomes so less indistinguishable in sandstone far away from coal seam that it transforms to the gas-storage effect, which is the same with tight sand and mud stone. Analysis concluded that this phenomenon is intimately associated with macroscopic type of coal and characteristic of micro-crack, isothermal adsorption and permeability.

The shipping industry is facing challenges to reduce exhaust gas emissions and greenhouse gases in particular, carbon dioxide from ships engaged in international trading. The main regulatory body, International Maritime Organization (IMO) and national environmental agencies of many countries have issued regulations that drastically reduce emissions coming from marine sources. Of particular note are regulations in Emissions Control Areas (ECAs) such as the North American ECA, which came into being in 2012, and the SOx Emission Control Areas (SECAs), which have been in effect in the Baltic Sea and North Sea and English Channel since 2006 and 2007, respectively. These new requirements will force ship owners and managers to look into other possibilities like using alternative fuels. The biodiesel is manufactured from vegetable oils, vegetable fats and algae, and it is a renewable and clean fuel which is reducing exhaust gas emissions and greenhouse emissions from

The growing number of motor vehicles on the street will increase the consumption of gasoline. At the national scale, gasoline consumption increased from 62.035.065 kiloliters in 2013 to 70.744.977 kiloliters in 2014. The increasing consumption of gasoline not only drains the non-renewable fossil energy but also affects the environment due to gas emission generated by fuel burning. The carbon monoxide (CO) or carbon dioxide (CO 2 ), hydrocarbon (HC), nitrogen oxide (No x ), particulate matter (PM), and sulfide (SO 2 ) concentration in a congestion area such as the area around traffic lights is substantially high. This research aims to find the gasoline consumption and emission rate in intersections with traffic lights, and its effect on surrounding environment. The research was done by collecting traffic volume in two locations in Surabaya, at morning rush hours, which started from 6.20 A.M. to 8.20 A.M, then calculated the emission rate and gasoline consumption from traffic data. The data showed that the volume of gasoline consumed in one lane (out of four lanes) at the traffic lights for two-hour duration was 700 liters, and the total substance of PM, NO, SO 2 produced were 353 grams, 15.166 grams, and 410 grams. The concentration of NO and SO 2 at Dr. Soetomo intersection after one-hour emission was 3059 μg/m 3 and 57 μg/m 3 , while that at Kertajaya intersection was 672 μg/m 3 and 12 μg/m 3 , respectively. These pollutants were away above the tolerable limit to human health as suggested by WHO, which should not exceed 50 μg/m 3 for PM, 40 μg/m 3 for NO 3 for NO, and 20 μg/m3 for SO 2 .

To face the increasing demand for animal products throughout the world, livestock-farming systems have been intensified. This intensification has proven to be economically effective but is noted for its negative impact on the environment through the production of ammonia (NH3) and the greenhouse gases nitrous oxide (N2O) and methane. In this context, dynamic models are useful tools to evaluate the effects of farming practice on nutrient flows and losses to the environment. This paper presents the development of a model simulating the flows of nitrogen (N) and phosphorus (P) in a rabbit production farm. The model is comprised of two submodels. The first submodel simulates the number of animals in the farm (births, deaths, culling of does/fatteners) and their respective performances (growth, feed intake, milk production). The second one simulates the excretion of N and P for each animal category using a mass-balance approach between intake (feed and/or milk intake) and exports (body deposition, milk production, gestation). Specific emission factors are then applied to the excreted N amounts to estimate total N, NH3 and N2O losses in the housing unit and during manure storage. Methane emissions from enteric fermentations and manure are also estimated. A simulation example based on French technico-economic data illustrates how the model could be used to study the dynamics of animal populations within the system and of nutrient flows. Finally, there is a need for new knowledge (experimental data) to improve the model and help design more sustainable rabbit production systems by identifying best practices that minimise environmental impacts.

This paper is focused on methods to indicate the environmental impact in terms of air pollutants of CHP (Combined Heat and Power) systems. The aim is to combine the energy saving achievement with information concerning the environmental benefit, in comparison with the non-CHP scenario. Environmental impact of CHP production both on global and local scale should be taken into account. In particular, the method of the “Avoided Heat Generator” is highlighted in this study as a proper approach for CHP and is used for a local-scale environmental impact evaluation. This approach calculates the reduction of emission due to CHP operation, taking into account the amount of pollutant emitted by an equivalent heat generator, which provides the same thermal power of the CHP prime mover. Moreover, the recommended approach is compared in the paper with another proposed method, based on the PSI (Pollutant Saving Index) value, which is suitable to estimate the global-scale environmental impact. Numerical evaluations of the CHP environmental benefits, in terms of NOx, CO and CO2 emissions, are shown for several CHP systems with different technologies and electric power sizes, in order to provide a comprehensive overview of current CHP prime mover environmental performance and to serve as an application reference example of the two methods potential use, in the framework of the CHP units authorization procedure. The significant effect of the reference comparative scenario is also highlighted.

This paper presents a mathematical model for solving Multi-Objective Optimal Power Flow problem considering uncertainties modeled by fuzzy numbers aecting three objective functions given by total generation cost, total gas emission and voltage profle index. The presented resolution approach is based on Genetic Algorithm (GA), where the parameters of this algorithm are determined and optimized after many tests of execution. A model for analyzing trade-off between profit and security constraint is developed. The probabilities of crossover and mutation optimized for GA parameters, dedicated to the presented approach are used to demonstrate a performance and effectiveness of the algorithm compared to other approaches mentioned in this paper. The mathematic model is applied in the Algerian electrical network for 59-bus test system.

In this paper, a Dynamic Economic/Emission Dispatch (DEED) problem is obtained by considering both the economy and emission objectives with required constraints dynamically. This paper presents an optimization algorithm for solving constrained combined economic emission dispatch (EED) problem and DEED, through the application of neural network, which is a flexible Hopfield neural network (FHNN). The constrained DEED must not only satisfy the system load demand and the spinning reserve capacity, but some practical operation constraints of generators, such as ramp rate limits and prohibited operating zone, are also considered in practical generator operation. The feasibility of the proposed FHNN using to solve DEED is demonstrated using three power systems, and it is compared with the other methods in terms of solution quality and computation efficiency. The simulation results showed that the proposed FHNN method was indeed capable of obtaining higher quality solutions efficiently in constrained DEED and EED problems with a much shorter computation time compared to other methods.

Gas emission is affected by many factors. Effects of atmospheric pressure on coal mine gas emission have become a rising concern. Basing on the gas emission at Y485 fully mechanized working face of Tangshan mine and atmospheric pressure, the paper had carried out online monitoring with sensors for 20 days continuously. Calculating the average values of atmospheric pressure and the expectation values of return air gas concentration of each hour on every monitoring date according to monitoring data, affection laws of atmospheric pressure to gas emission at fully mechanized working face were studied combining the weather and temperature of monitoring dates. It pointed out that the atmospheric pressure declines along with the rising of temperature and the gas emission at fully mechanized working face could be restrained if the atmospheric pressure rises, otherwise it could be promoted to release, the affection of variation of atmospheric pressure to gas emission was 0.0575%/hPa on cloudy day, and was 0.0446%/hPa on sunny day, and it was predicted that the peak time of gas emission at fully mechanized working face was from 12 o’clock to 16 o’clock according to the data processing results.