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Summary: Coal is the most abundant energy source, and around 40% of the world's electricity is produced by coal combustion. The emission generated through it put a constraint on power production by coal combustion. There is a need to reduce the emissions generated through it to utilize the enormous energy of coal for power production. Detailed understanding of various aspects of coal combustion is required to reduce the emissions from coal‐fired furnaces. The aim of present paper is to review various aspects of pulverized coal combustion such as oxy‐fuel combustion, co‐combustion of coal and biomass, emissions from pulverized coal furnaces, ash formation and deposition, and carbon capture and sequestration (CCS) technologies to outline the progress made in these aspects. Both experimental and numerical aspects are included in this review. This review also discusses the thermodynamic aspects of the combustion process. Furthermore, the effect of various submodels such as devolatilization models, char combustion models, radiation models, and turbulent models on the process of pulverized coal combustion has been investigated in this paper. [ABSTRACT FROM AUTHOR]

Oxy-fuel combustion is an effective technology for carbon capture and storage (CCS). Oxy-combustion for coal-fired power stations is a promising technology by which to diminish CO2 emissions. Unfortunately, little attention has been paid to the oxy-combustion characteristics affected by the combustion atmosphere. This paper is aimed at investigating the oxy-fuel combustion characteristics of Australian coal in a 0.3 MWth furnace. In particular, the influences of various oxygen flow rates and recirculated flue gas (RFG) on heating performance and pollutant emissions are examined in O2/RFG environments. The results show that with increases in the secondary RFG flow rate, the temperatures in the radiative and convective sections decrease and increase, respectively. At a lower oxygen flow rate, burning Australian coal emits lower residual oxygen and NO concentrations. In the flue gas, a high CO2 concentration of up to 94.8% can be achieved. Compared to air combustion, NO emissions are dramatically reduced up to 74% for Australian coal under oxy-combustion. Note that the high CO2 concentrations in the flue gas under oxy-coal combustions suggest great potential for reducing CO2 emissions through carbon capture and storage. [ABSTRACT FROM AUTHOR]

As a part of the strategic research program 'Advanced technologies for energy generation: Development of a technology for highly efficient zero-emission coal-fired power units integrated with CO capture', a mobile CO absorption pilot plant was erected. The main purpose of the pilot plant was to demonstrate the post-combustion technology in conjunction with a coal-fired power plant. The pilot plant captured CO by chemical absorption in amine-based solvents, which was considered to be the best adapted technology to the requirements of coal-fired power plants and suitable for retrofitting to existing units. The pilot plant captured up to 1000 kg/day of CO from the power plant's flue gases with CO recovery exceeding 90 %. The flexible process flowsheet of the pilot plant offered high potential for the validation of various improvements, which were designed to reduce the process energy demand and to increase the CO recovery. This paper summarizes the initial operation experience at the TAURON Łaziska Power Plant in Poland. Selected first results obtained are presented and discussed. The initial campaigns utilized 20 and 30 wt% monoethanolamine (MEA) solutions recognized as baseline solvents that were suitable for comparative purposes. The initial campaigns at the pilot plant successfully demonstrated reliable operation and promising results. [ABSTRACT FROM AUTHOR]

This paper presents the results of chemical looping combustion (CLC) research. Nowadays, CLC is one of the best prospective combustion technologies, because it enables the production of a concentrated carbon dioxide (CO 2 ) stream, following water condensation, without any energy penalty for its separation. The objective of this work was to study chemical looping reaction performance with the application of novel perovskite-type oxygen carriers (OCs). Sr(Fe 1-x Cu x )O 3-δ family members were tested for hydrogen combustion for power generation purposes. Sr(Fe 1-x Cu x )O 3-δ , which is a perovskite-type oxide, was prepared using the calcination method, where x = 0, 0.1 and 0.33. Reactivity tests were performed using a thermogravimetric analyser (TGA, Netzsch STA 409 PG Luxx) under isothermal conditions in multiple reduction–oxidation cycles. Both the temperature (600–800 °C) and number of redox cycles (five cycles) effects on the reaction performance of recently developed OC samples were evaluated in the study. TGA data were used for the assessment of the oxygen transport capacity value, redox reaction rates and stability. Sr(Fe 1-x Cu x )O 3-δ showed an excellent stable chemical looping performance. The changing of oxygen content (3.8–4.86 wt%) occurred within approximately 2 min, with the chemical properties of the material maintained during the cycling combustion tests. In addition, new SrFeO 3-δ OCs, doped with copper (Cu) perovskite-type materials, were analysed using multiple methods: X-ray powder diffraction (XRD); scanning electron microscopy (SEM); surface area by Brunauer–Emmett–Teller (BET) method; and melting behaviour study. In terms of physical properties, the new OCs can resist both high CLC process temperatures and mechanical forces, which are essentially useful. The analysis showed that Sr(Fe 1-x Cu x )O 3-δ carriers performed at extremely high melting temperatures (>1280 °C). Results of crushing strength testing showed that developed materials had a pronounced mechanical resistivity with a crushing strength higher than 1 N and will perform well in fluidized beds (4.31–6.23 N). In this paper, it was demonstrated that known mixed oxygen-ionic and electronic conducting membrane materials such as Sr(Fe 1-x Cu x )O 3-δ might also be applied as oxygen carriers. Overall results demonstrated Fe-Cu-based perovskites might be successfully used as OCs in the chemical looping combustion process. [ABSTRACT FROM AUTHOR]

Engineering efforts to handle contemporary energy supply challenges and mitigate pollutant emission lead towards more complicated systems. Power plants are supplementing with additional processing units, alternative production modes and higher level of automation. Wind and solar sources, biomass combustion, gasification, carbon capture and storage (CCS), and cogeneration have appeared as important players in the energy systems. The increasing complexity comprises a risk that the systems become less manageable and less stable than currently. Traditional steady-state engineering methods cannot fully address these challenges that are inherently dynamic in their nature. Dynamic process simulation appears as important tool to the systems design and optimisation tasks. A large variety of dynamic process modelling and simulation approaches has been presented recent years. This paper presents a brief review of methods and simulation packages that are generally applied for studying energy systems' transient behaviour. A CCS capable power plant is presented as an example of utilizing dynamic process simulation for virtual evaluation of a novel electricity production concept. The modelling was performed using two simulators Apros and Aspen Plus Dynamics, which were linked together for dynamic simulating the full chain of cryogenic oxygen distillation, oxy combustion, turbine islands and carbon dioxide purification and liquefaction operations. • Dynamic simulations for design and optimisation of contemporary energy systems have been reviewed. • A case study for evaluating oxy combustion CFB boiler cycle with carbon capturing is presented. • Co-simulation with two dynamic process simulation software: Apros and Aspen Plus Dynamics were shown. • Flexibility aspects of oxy combustion power plant are discussed. [ABSTRACT FROM AUTHOR]

Abstract: This paper estimates the cost of CO2 capture for three Australian industrial emission sources: iron and steel production, oil refineries and cement manufacturing. It also compares the estimated capture costs with those of post-combustion capture from a pulverised black coal power plant. The cost of capture in 2008 using MEA solvent absorption technology ranges from less than A$60 per tonne CO2 avoided for the iron and steel production to over A$70 per tonne CO2 avoided for cement manufacture and over A$100 per tonne CO2 avoided for oil refineries. The costs of capture for the iron and steel and cement industries are comparable to or less than that for post-combustion capture from a pulverised black coal power plant. This paper also investigates costs for converting low partial pressure CO2 streams from iron and steel production to a more concentrated stream using pressurisation and the water-gas shift reaction. In those cases, the costs were found to be similar to or less than the cost estimates without conversion. The analyses in this paper also show that estimated costs are highly dependent on the characteristics of the industrial emission source, the assumptions related to the type and price of energy used by the capture facilities and the economic parameters of the project such as the discount rate and capital costs. [ABSTRACT FROM AUTHOR]

The use of natural gas for power generation is becoming increasingly important in many regions in the world. Given that the combined cycle gas turbine (CCGT) power stations are lower in capital cost and carbon intensity than their coal-fired counterparts, natural gas fired power stations are considered a vital part of the transition to a low carbon economy. However, CCGTs are not themselves “low carbon” and in order to reach a carbon intensity of less than 50 kg CO 2 /MWh, it will be necessary to decarbonise them via CCS, with post-combustion CCS currently regarded as being a promising technology for this application. In this study, we present a detailed model of a 420 MW triple-pressure reheat CCGT and evaluate its technical and economic performance under full and part load conditions. We evaluate the technical performance of our CCGT model by comparison to an equivalent model implemented in Thermoflow THERMOFLEX and observe agreement of power output and efficiency to within 4.1% and the temperature profile within the HRSG within 2.9%. We further integrate the CCGT with a dynamic model of an amine based CCS process, and observe a reduction in the base plant efficiency from 51.84% at full-load and 50.23% at 60% load by 8.64% points at full-load and 7.93% points at 60% load. A core conclusion of this paper is that CCGT power plants equipped with post-combustion CCS technologies are well suited to dynamic operation, as might be required in an energy system characterised by high penetrations of intermittent renewable power generation. [ABSTRACT FROM AUTHOR]

Abstract: CO2 capture by chemical or physical sorption and membrane separation have been the dominant fields of research within post- and pre-combustion CO2 capture from power cycles and industrial processes. Except for oxy-combustion capture applications, limited attention has been given to low-temperature capture from flue gas and synthesis gas by phase separation. This paper gives an overview of common CO2 capture conditions for a broad range of different power cycles and industrial processes. For a selected range of capture conditions, potential applications for low-temperature CO2 capture have been evaluated with respect to energy consumption and CO2 capture ratio. For all applications of low-temperature capture, specific power consumption and obtainable CO2 capture ratio are sensitive to flue-gas or synthesis-gas feed CO2 concentration. However, for certain applications such as synthesis gas from coal gasification, low-temperature capture shows promising potential and highly competitive energy figures compared to baseline technology. [Copyright &y& Elsevier]

Carbon capture, transport and storage (CCS) is a very active field of research, because of its potential to make large reductions of emissions from fossil fuel combustion relevant to climate change. This paper reviews the recent and current work on practical injections of CO2 as research tests for storage projects and specifically focuses on industrial-scale or relevant injections into saline formations (about 1 Mt CO2 per year). All injection projects around the world have been reviewed, and 20 are reported to compile, depth, reservoir quality and injectivity, cost, and rate. This shows that testing of injection is concentrated onshore; however the projects with the highest total CO2 storage estimate are offshore. Pipeline transport systems are mostly used for the large projects. Formations targeted in the injection process are sandstone or carbonate. In the majority of cases initial projections of injectivity are confirmed in tests. A variety of monitoring techniques are used in all projects, these have detected CO2, but have not shown unexpected CO2 movement. Practical experiences of CO2 injection operations therefore suggest that similar operations can be successfully carried out in the saline formations of the UK North Sea and other large sedimentary basins. [ABSTRACT FROM AUTHOR]

Abstract: Carbon dioxide is more and more pointed out as one of the factors mostly responsible of climate changes. As a consequence the reduction of CO2 emissions, especially in the energy generation field, is becoming a worldwide must. This paper presents an overview on the main issues that are expected to affect, from this standpoint, power generation scenario and a spur for a critical comparison among ways to capture CO2 by proposing new aspects to be considered within the evaluation criteria. In particular attention is drawn on the fully innovative opportunities that are offered by Molten Carbonate Fuel Cells (MCFCs) as a unique option suitable to effectively combine carbon capture from thermal plants and typical benefits of hydrogen and fuel cell power generation. As an example, such a new option is compared with one of the most common technologies forecast for reducing carbon dioxide emissions and relevant results are shortly presented. [Copyright &y& Elsevier]

Abstract: Adding post-combustion capture technology to existing coal-fired power plants is being considered as a near-term option for mitigating CO2 emissions. To supply the thermal energy needed for CO2 capture, much of the literature proposes thermal integration of the existing coal plant’s steam cycle with the capture process’ stripper reboiler. This paper examines the option of using an auxiliary natural gas turbine plant to meet the energetic demands of carbon capture and compression. Three different auxiliary plant technologies were compared to integration for 90% capture from an existing, 500 MW supercritical coal plant. CO2 capture (via a monoethylamine (MEA) absorption process) and compression is simulated using Aspen Plus. Thermoflow software is used to simulate three gas plant technologies. In some circumstances, it is found that using an auxiliary natural gas turbine may make retrofits more attractive compared to using thermal integration. The most important factors affecting desirability of the auxiliary plant retrofit are the cost of natural gas, the full cost of integration, and the potential for sale of excess electricity. [Copyright &y& Elsevier]

Abstract: This paper discusses the energy penalty of solvent based post combustion capture for three different power stations and includes a comparison of shockwave CO2 compression versus conventional turbo machinery on the energy penalty associated with carbon capture and storage. This study uses pinch analysis to determine targets for the energy penalty of three different power stations that include a brown coal power plant with no reheat stage, a more efficient brown coal power station and a black coal power station. Heat integration can be used to reduce the energy penalty of all power stations combined with CCS. It is also found that when heat integration is considered, the heat that can be recovered in shockwave compressor inter/after-coolers reduces the amount of steam that needs to be extracted from the steam turbine. Hence, the net power output from the power station will be higher when shockwave compressors are used for CO2 compression compared to conventional turbo-machinery. [Copyright &y& Elsevier]

Abstract: Commissioned in 2009, the CO2CRC/H3 Capture Project is demonstrating post-combustion carbon capture (PCC) on a lignite fired power plant in the Latrobe Valley, Victoria, Australia. The facility is located within International Power’s Hazelwood Power Plant and uses three different CO2 capture technologies — solvent, adsorption and membrane processes. This project, addressing the PCC issues specific for Victorian brown coal fired power stations, was initiated in July 2007 as a three year research project by the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC) under the Victorian State Government’s Energy Technology Innovation Strategy (ETIS) program. The project is part of the Latrobe Valley Post Combustion Capture (LVPCC) Project — a multi site, multi scale, multi technology PCC trial. The integrated research and development program includes an evaluation of these technologies for commercial scale application. This paper describes the technologies used, how they have progressed from laboratory to pilot demonstration, the main outcomes, and plans for future developments. [Copyright &y& Elsevier]

Abstract: In May 2007, E.ON Group (E.ON) set an ambitious target for reducing the specific CO2 emissions of the overall group’s electricity generation. By 2030, E.ON will reduce the specific CO2 emissions to 360 grams per kilowatt hour, half the 1990 figure. Thus, besides increasing the share of renewables and maintaining the nuclear share, E.ON identified the need to advance the technology of fossil fuel fired power plants. E.ON pursues a strategy of replacing power stations at the end of their life cycle with new, state-of-the-art power stations which are ready to be equipped with CCS (carbon capture and storage) and therefore “capture ready”. Moreover, E.ON is developing CO2 capture and storage as this technology has the potential to drastically reduce emissions from coal-fired plants. Beginning in 2020, E.ON intends to have large scale CCS technology available. E.ON’s coordinated strategy encompasses research, development and demonstration (RD&D) and is directed towards pre combustion capture, oxyfuel and post combustion capture with a focus on the latter. E.ON is working together with international partners to further develop the existing technologies for capturing of CO2 by testing advanced technologies in several pilot plants at our sites. The goal of the pilot projects is to optimise the downstream capture of CO2 from flue gas (post combustion capture) hence reducing the auxiliary power consumption of the capture process. An update on the pilot projects, suppliers and achievement made will be given. Besides improving the capture process itself the technology needs a significant increase of the treatable flue gas capacity compared to today’s limits known from chemical industry. Therefore E.ON is also involved in the development of demo scale projects proving the feasibility of the full CCS chain (including transport and storage). E.g. our Kingsnorth power station in the UK has entered the next stage of the UK Government’s carbon capture and storage (CCS) competition after developers. We submitted an Outline Solution Bid competition on 9 November 2009. The competition is aiming to deliver the UK’s first fullscale CCS demonstration project. We have come to an agreement with both the European Commission and the Dutch Government on the funding of our ROAD-project. This is our joint project with Electrabel (part of GDF SUEZ) at RotterdamMaasvlakte (NL). The Dutch part of the funding is now before the European Commission for State Aid approval. We will report about the projects and the progress made in our market units. In addition E.ON is engaged in the development of storage sites and transport routes for CO2. Our business unit E.ON Gas Storage is involved in several research and development activities. The paper will highlight E.ON’s main CCS activities. An overview will be given as well as an update on the status of the current projects and available results. [Copyright &y& Elsevier]

Abstract: The Dutch Ministry of Spatial Planning and the Environment (VROM) engaged Jacobs Consultancy to develop a definition and measuring tool aimed at quantifying the CO2 Capture Readiness of a combustion plant. The tool developed tests the level and completeness of pre-project execution information. The testing of pre-project information is a standard practice in the refining and petrochemical industry and Jacobs Consultancy has adapted and tailored these practices to develop the Capture Readiness tool. The tool was developed in 2008 and was pilot tested on two already permitted coal fired power plant projects in 2009. The Capture Readiness tool is similar in concept to the well known Project Definition Rating Index originally introduced by the Construction Industry Institute for Major Capital Projects. The tool quantifies the readiness of a project to accommodate future CO2 capture and parallels the phased approached to Major Capital Projects used by the Project Definition Rating Index. A short introduction to the application of the PDRI methodology to test the completeness of the project development information–often also referred to as Front End Loading or FEL, is included in this paper to establish the parallel approach we have used in the development of the Capture Readiness tool. The Jacobs Consultancy Capture Readiness tool is then discussed in more detail. [Copyright &y& Elsevier]

Abstract: This paper presents an environmental assessment of three scenarios postulating a national deployment of the Carbon Capture and Storage (CCS) chain by 2020–2050 on the French biggest industrial CO2 emitters (41 emitters among 9 industrial sectors) that had been carried out as part of the SOCECO2 project. 1 [1] SOCECO2 project, funded by the French National Research Agency, 2006–2009, involving the following partners: ALSTOM Power, APESA, BRGM, CNRS-CIRED, GDF Suez, IFP Energies nouvelles, INERIS, TOTAL. This analysis is based on the comparison of these CCS scenarios with reference scenarios without CCS at the same timeframe. Results detailed below focus on greenhouse gas (GHG) emissions and energy consumption, although NOx and SOx emissions balances have also been evaluated in the same project. Conclusions of this study provide information about the extent and main contributing factors of potential environmental outcomes (negative or positive) associated to CCS deployment. [Copyright &y& Elsevier]

Abstract: The oxy-fuel process is one of three carbon capture technologies which supply CO2 ready for sequestration – the others being post-combustion capture and IGCC with carbon capture. As yet no technology has emerged as a clear winner in the race to commercial deployment. The oxy-fuel process relies on recycled flue gas as the main heat carrier through the boiler and results in significantly different flue gas compositions. Sulphur has been shown in the study to have impacts in the furnace, during ash collection, CO2 compression and transport as well as storage, with many options for its removal or impact control. In particular, the effect of sulphur containing species can pose a risk for corrosion throughout the plant and transport pipelines. This paper presents a technical review of all laboratory and pilot work to identify impacts of sulphur impurities from throughout the oxy-fuel process, from combustion, gas cleaning, compression to sequestration with removal and remedial options. An economic assessment of the optimum removal is not considered. Recent oxy-fuel pilot trials performed in support of the Callide Oxy-fuel Project and other pilot scale data are interpreted and combined with thermodynamic simulations to develop a greater fundamental understanding of the changes incurred by recycling the flue gas. The simulations include a sensitivity analysis of process variables and comparisons between air fired and oxy-fuel fired conditions - such as combustion products, SO3 conversion and limestone addition. [Copyright &y& Elsevier]

Abstract: Using CO2/N2 gas separation membranes for post-combustion capture, the most important problem is how to create the driving force efficiently because the feed flue gas has only ambient pressure and a relatively low CO2 content. In order to fulfill the separation target – 95mol% CO2 purity and appropriate degree of CO2 separation – multi-stage systems are necessary using feasible membranes. This paper describes a detailed parametric study for multi-stage membrane systems used in a coal-fired power plant. According to the above-mentioned boundary conditions, the investigation process was divided into two steps: (a) energy consumption and (b) capture cost analyses. In the first step, by varying the position of the compressors and vacuum pumps and recycling the flue gas to the feed side, cascade variants were developed and analyzed in detail. The cascade system was integrated in the 600MW North Rhine-Westphalia reference power plant and compared with the chemical absorption process. In the second step, an economic model was developed to make a further analysis of the cascade system. A correlation was established between the membrane parameters (selectivity, permeability) and system performance (energy consumption, capture cost). [Copyright &y& Elsevier]

This paper presents the Life Cycle Assessment (LCA) analysis concerning the selected options of supercritical coal power units. The investigation covers a pulverized power unit without a CCS (Carbon Capture and Storage) installation, a pulverized unit with a "post-combustion" installation (MEA type) and a pulverized power unit working in the "oxy-combustion" mode. For each variant the net electric power amounts to 600 MW. The energy component of the LCA analysis has been determined. It describes the depletion of non-renewable natural resources. The energy component is determined by the coefficient of cumulative energy consumption in the life cycle. For the calculation of the ecological component of the LCA analysis the cumulative CO2 emission has been applied. At present it is the basic emission factor for the LCA analysis of power plants. The work also presents the sensitivity analysis of calculated energy and ecological factors. [ABSTRACT FROM AUTHOR]

The Solid Sorbent Technology (SST) is a breakthrough technology which separates CO 2 from flue gas in a continuous Temperature Swing Adsorption (TSA) fluidized bed process using solid adsorbent. The technology simultaneously delivers > 90% CO 2 capture efficiency and > 95% CO 2 purity with low to no process related emissions and at lower capture costs compared to state-of-the-art liquid amines technology. This paper will discuss results of a 900 h piloting campaign using Lewatit VP OC 1065 adsorbent and its impact on the cost comparison with liquid amines technology. The successful operation of the pilot plant and finalization of the test campaign marked the progression of the technology readiness level from TRL4 to TRL6. [ABSTRACT FROM AUTHOR]

Detailed analyses based on mass and energy balances of lignite-fired air-blown gasification-based combined cycles with CO2 pre-combustion capture are presented and discussed in this work. The thermodynamic assessment is carried out with a proprietary code integrated with Aspen Plus® to carefully simulate the selective removal of both H2S and CO2 in the acid gas removal station. The work focuses on power plants with two combustion turbines, with lower and higher turbine inlet temperatures, respectively, as topping cycle. A high-moisture lignite, partially dried before feeding the air-blown gasification system, is used as fuel input. Because the raw lignite presents a very low amount of sulfur, a particular technique consisting of an acid gas recycle to the absorber, is adopted to fulfill the requirements related to the presence of H2S in the stream to the Claus plant and in the CO2-rich stream to storage. Despite the operation of the H2S removal section representing a significant issue, the impact on the performance of the power plant is limited. The calculations show that a significant lignite pre-drying is necessary to achieve higher efficiency in case of CO2 capture. In particular, considering a wide range (10-30 wt.%) of residual moisture in the dried lignite, higher heating value (HHV) efficiency presents a decreasing trend, with maximum values of 35.15% and 37.12% depending on the type of the combustion turbine, even though the higher the residual moisture in the dried coal, the lower the extraction of steam from the heat recovery steam cycle. On the other hand, introducing the specific primary energy consumption for CO2 avoided (SPECCA) as a measure of the energy cost related to CO2 capture, lower values were predicted when gasifying dried lignite with higher residual moisture content. In particular, a SPECCA value as low as 2.69 MJ/kgCO2 was calculated when gasifying lignite with the highest (30 wt.%) residual moisture content in a power plant with the advanced combustion turbine. Ultimately, focusing on the power plants with the advanced combustion turbine, air-blown gasification of lignite brings about a reduction in HHV efficiency equal to almost 1.5 to 2.8 percentage points, depending on the residual moisture in the dried lignite, if compared with similar cases where bituminous coal is used as fuel input. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]