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The purpose of this paper is to show possible approaches which can be used for modeling complex flow phenomena caused by swirl burners combined with simulating coal combustion process using air- and oxy-combustion technologies. Additionally, the response of exist boiler working parameter on changing the oxidizer composition from air to a mixture of the oxygen and recirculated flue gases is investigated. Moreover, the heat transfer in the superheaters section of the boiler was taken into account by modeling of the heat exchange process between continuum phase and three stages of the steam superheaters.

An accurate solution of the flow field is required in order to predict combustion phenomena correctly for numerical simulations of the industrial pulverized coal (PC) boilers. Nevertheless, it is a very demanding task due to the complicated swirl burner construction and complex character of the flow. The presented simulations were performed using the discrete phase model for tracking particles and combustion phenomena in a dispersed phase, whereas the Eulerian approach was applied for the volatile combustion process modeling in a gaseous phase.

Applying the air- to oxy-combustion technology the temperature in the combustion chamber, decreased for investigated oxidizer compositions. This was caused by the higher heat capacity of flue gases which also influences on the level of the heat flux at the boiler walls. Simulations shows that increasing the O₂ concentration to 30 percent of volume base in the oxidizer mixture provided the similar combustion conditions as those for the conventional air firing. Moreover, the evaluated results give a good overview of differences between approaches used for complex swirl burners simulations.

Nowadays, the numerical techniques such as computational fluid dynamic (CFD) can be seen as an useful engineering tool for design and processes optimization purposes. The application of the CFD gives a possibility to predict the combustion phenomena in a large industrial PC boiler and investigate the impact of changing the combustion technology from a conventional air firing to oxy-fuel combustion.

This paper gives good overview on existing technique, approaches used for modeling PC boiler equipped with complex swirl burners. Additionally, the novelty of this work is application of the heat exchanger model for predicting heat loses in convective section of the boiler. This usually is not taken into account during simulations. The reader can also find basic concept of oxy-combustion technology, and their impact on boiler working conditions.

The main goal of this work was the CFD analysis of air and oxy-coal combustion, in order to develop a validated with experimental measurements model of the combustion chamber. Moreover, the purpose of this paper is to provide information about limitations of the sub-models implemented in commercial CFD code ANSYS Fluent version 13.0 for the oxy-coal combustion simulations. The influence of implementation of the weighted sum of gray gas model (WSGGM) with coefficients updated to oxy-coal combustion environment has been investigated.

The sub-models validated with experimental measurements model for the air combustion has been used to predict the oxy-coal combustion case and subsequently the numerical solutions have been compared with the experimental data, which enclose the surface incident radiation (SIR) and the flue gas temperature. To improve the numerical prediction of the oxy-coal combustion process the own routine for calculating properties of the oxy-combustion product has been implemented.

The results of numerical simulation of combustion in the air environment fitted within the experimental measurements accuracy. However, the air combustion sub-models implemented for the oxy-coal combustion simulations does not predict the SIR within the experimental data accuracy. The implementation of own routine, which uses the coefficients calculated for oxy-coal combustion environment shows improvement in numerical prediction of oxy-coal combustion.

The radiative properties of gases in the combustion chamber during oxy-coal combustion calculated using the WSGGM implemented in ANSYS Fluent 13.0 do not predict the SIR within experimental measurement accuracy, however, implementation of WSGGM with updated coefficients provide a reasonable improvement in numerical prediction of SIR in the oxy-coal combustion.

In Turkey, dependence on foreign countries for energy is a problem which upsets all economic balances. Turkey’s biggest fossil energy source is lignite coal. Therefore, energy conversion of lignite in thermal plants, causing minimum environmental effect is extremely important. The basic problem in terms of the combustion technology is to improve the combustion technology that can burn the low-qualified fuels that do not have standard fuel features (lignite, peat, schist). The most suitable technology today for the efficient and clean combustion of nonstandard low-qualified fuels is the combustion at fluidized-bed technology. In this study, CO₂ emission that occurs during the combustion of Orhaneli coal that is one of our native low-qualified lignite, has been investigated according to the experimental study.

For this combustion experiment, laboratory-scaled circulating fluidized-bed (CFB) process that exists at TÜBITAK-MAM Energy Institute which has been designed and used before has been used. The effect of excess-air coefficient, combustion type and bed temperature to the greenhouse gas formation and CO₂ emission has been investigated experimentally. In terms of flue gas emissions, it has been detected that the decrease of the amount of CO₂ that has occurred has no positive effects on combustion efficiency, water vapor, SO₂, NO_x, CO and other gases which occur during deficient combustion must be thought as a whole and each reaction affects each other similar to complex reactions.

As a consequence of measuring CO₂ emissions over 10 minute periods, CO₂ emissions are 12.43 percent average, CO₂ decreases at different air coefficient values; Often form undesirable side reactions such as CO, NOx with back and forth reactions.

The importance of aerodynamic structure of the system, and the losses and leakages forming in the system has been observed experimental and affected parameters are evaluated.

The aim of this study is to assess the role of CO₂ capture and storage (CCS) technologies in the reduction of CO₂ emissions from European industries.

A database covering all industrial installations included in the EU ETS has been created. Potential capture sources have been identified and the potential for CO₂ capture has been estimated based on branch‐ and plant‐specific conditions. Emphasis is placed here on three branches of industry with promising prospects for CCS: mineral oil refineries, iron and steel, and cement manufacturers.

A relatively small number (∼270) of large installations (>500,000 tCO₂/year) dominates emissions from the three branches investigated in this study. Together these installations emit 432 MtCO₂/year, 8 percent of EU's total greenhouse gas emissions. If the full potential of emerging CO₂ capture technologies was realized, some 270‐330 MtCO₂ emissions could be avoided annually. Further, several regions have been singled out as particularly suitable to facilitate integrated CO₂ transport networks. The most promising prospects for an early deployment of CCS are found in the regions bordering the North Sea.

Replacement/retrofitting of the existing plant stock will involve large investments and deployment will take time. It is thus important to consider how the current industry structure influences the potential to reduce CO₂ in the short‐ medium and long term. It is concluded that the age structure of the existing industry plant stock and its implications for the timing and deployment rate of CO₂ capture and other mitigation measures are important and should therefore be further investigated.

CCS has been recognized as a key option for reducing CO₂ emissions within the EU. This assessment shows that considerable emission reductions could be achieved by targeting large point sources in some of the most emission‐intensive industries. Yet, a number of challenges need to be resolved in all parts of the CCS chain. Efforts need to be intensified from all stakeholders to gain more experience with the technological, economical and social aspects of CCS.

This study provides a first estimate of the potential role for CO₂ capture technologies in lowering CO₂ emissions from European heavy industry. By considering wider system aspects as well as plant‐specific conditions the assessment made in this study gives a realistic overview of the prospects and practical limitations of CCS in EU industry.

The purpose of this paper is to present a new approach of evaluation of the absorption line black body distribution function (ALBDF) for a mixture of gases. Currently published correlations, which are used to reproduce the ALBDF, treat only single gases.

A discrete form of the ALBDF is generated using line by line (LBL) calculations. The latest spectroscopic database HITEMP 2010 is used for the generation of the absorption coefficient histogram, which is cumulated later in order to produce a tabulated form of the ALBDF. The proper orthogonal decomposition (POD) statistical method is employed for the reproduction of the ALBDF. Interpolation property of the POD allows to reproduce the ALBDF for arbitrary gas mixture parameters.

POD proved to possess optimal interpolation properties. Results obtained by using POD are in very good agreement with LBL integration.

One have to be aware that the model generated with the POD method can be used only within the range of parameters used to build the model. The POD does not perform any property extrapolation. The model is limited to a mixture of two gases, namely CO₂ and H₂O. Expanding the number of gases used in the mixture may lead to a relatively large matrix system, which is difficult to process with the POD approach.

The presented approach can be used to produce absorption coefficients values and their weights, which can be applied in the gas radiative properties description using the weighted sum of gray gas (WSGG) concept. The proposed model can be used with any radiative transfer equation solver which employs the WSGG approach.

For the first time, radiative properties of gas mixtures are reproduced using the POD approach.

Cement industry for both developed and developing countries is important from the economic point of view. It is playing a vital role in economic development of a developing country like Pakistan. However, these industries are posing threat to the environment, human health and plant species. The purpose of this paper is to identify the most critical factors of cement industry that have a negative impact on the environment, human health and plant species in the context of Pakistan.

The factors are categorized into air pollution, noise pollution, soil pollution, human health and plant species. These factors are categorized on the basis of previous literature and environmental safety reports. Air pollution is caused by iron and sulphur while noise pollution is mainly caused by crusher room and rotatory kiln end. The soil is being polluted by zinc and lead while human health and plant species are being damaged by sulphur dioxide and nitrogen dioxide. For the analysis purpose, a multi-criteria decision-making (MCDM) technique, i.e., decision-making trial and evaluation laboratory (DEMATEL) is used.

The result shows that the major cause of air pollution is “sulphur” while “crusher room and rotatory kiln end” are responsible for noise pollution. On the other hand, “mercury” is responsible for causing soil pollution while human health and plant species are influenced by the toxic effect of “nitrogen dioxide.”

The results obtained are specific to cement manufacturing industry of Pakistan and cannot be generalized for any other manufacturing sector.

The proposed methodology shows the most critical factors toward which concertation should be given for mitigating their impact. This study will help the government and the cement industry to focus on all those elements that are the most responsible for causing different types of pollution.

No such work is reported in previous research that proposes a framework using DEMATEL technique for analysis of critical factors of cement industries that have a dangerous impact on the environment and human health, especially in a developing country, like Pakistan.

Coal, a fuel that once dominated the global energy scene, is staging a come‐back despite being environmentally dirty. The purpose of the paper is to analyse the return of King Coal to find out whether it is likely to be regain its dominance in the global energy in the future.

In analysing the metamorphosis of the coal industry, the paper looks at the historical evolution of the industry and analyses the factors behind the change. The deficiencies of coal's competitors are also analysed. Using a scenario analysis, the future role of coal in the global energy mix is estimated as well.

The paper finds that despite the domination of hydrocarbons in the global energy mix, coal has maintained a steady share and in some countries, it remained the main fuel. With the concerns of high‐oil prices and peak oil, coal is regaining its domination in the power sector around the world. The industry has reformed and restructured itself to remain competitive. Consequently, it has the possibility of staging a come back as a dominant fuel.

The paper is the first of its kind to take a long‐term perspective of the coal industry to analyse its re‐emergence as a dominant fuel. It combines the industry‐wide information to analyse the changes that swept the industry. It contributes by improving the academic understanding of a neglected fuel that still plays an important role.

The purpose of this paper is to estimate different air–fuel ratio motor shaft speed and fuel flow rates under the performance parameters depending on the indices of combustion efficiency and exhaust emission of the engine, a turboprop multilayer feed forward artificial neural network model. For this purpose, emissions data obtained experimentally from a T56-A-15 turboprop engine under various loads were used.

The designed multilayer feed forward neural network models consist of two hidden layers. 75% of the experimental data used was allocated as training, 25% as test data and cross-referenced by the k-fold four value. Fuel flow, rotate per minute and air–fuel ratio data were used for the training of emission index input values on the designed models and EI_CO, EI_CO2, EI_NO2 and EI_UHC data were used on the output. In the system trained for combustion efficiency, EI_CO and EI_UHC data were used at the input and fuel combustion efficiency data at the output.

Mean square error, normalized mean square error, absolute mean error functions were used to evaluate the error obtained from the system as a result of the test. As a result of modeling the system, absolute mean error values were 0.1473 for CO, 0.0442 for CO₂, 0.0369 for UHC, 0.0028 for NO₂, success for all exhaust emission data was 0.0266 and 7.6165e-10 for combustion efficiency, respectively.

This study has been added to the literature T56-A-15 turboprop engine for the current machine learning methods to multilayer feed forward neural network methods, exhaust emission and combustion efficiency index value calculation.

The use of CO₂ as a replacement for conventional air in combustion gas streams of gas turbine power‐generation equipment is a novel idea and a potential method of providing an almost pure CO₂ stream for subsequent disposal/sequestration. The purpose of this paper is to investigate the effects of this novel gas environment on conventional gas turbine component part materials over the same range of temperatures found in service.

Test samples of candidate materials were tested in simulated environments using controlled gas and steam supplies to sealed horizontal laboratory furnaces. Conventional weight change tests, metal loss tests and electron microscope examination were used to assess the performance of the materials and compare the oxidation morphology. Spectra of the oxidation products were also used to determine the nature of the oxides formed on selected materials.

It is found that changes in the percentage of steam in the novel gas environment made little difference to the performance of the selected alloys. However, when the results of the program are compared with typical data from previous works, where the same alloys are exposed in air, there is a distinct trend. Comparison between the data from air exposed samples and data from those in this paper show the high CO₂ environment, envisaged for the GAS‐ZEP concept, to be more aggressive to all of the alloys tested.

This paper describes the first investigation into the performance of candidate materials for the various components around a GAS‐ZEP system in the novel operating environments anticipated. The work has shown that current power plant materials can be considered for use in first generation GAS‐ZEP systems, but that care is required in their selection at the higher operating temperatures.