Oxy-fuel Technology Research Articles

Improving the energy efficiency of carbon capture process: The thermodynamic insight

The efficient use of energy is an important challenge in engineering tasks. Even with the end-of-pipe treatment method, the carbon capture process has possibilities to improve its efficiency with heat integration. Since exergy analysis helps detect the most efficient way of energy intensification, exergy investigation based on thermodynamic analysis is carried out to improve energy efficiency. Two cases for exergy destruction calculation can be considered and compared depending on the operation of the capture process: (i) the stand-alone situation, where utilities are applied, and (ii) the total site integration, where sources and sinks are available at every temperature level of the carbon capture process. Besides heat integration, the application of oxyfuel technology can further improve thermodynamic efficiencies reducing the detrimental exergy destruction. Air-combustion exhibits higher exergy destruction compared to oxyfuel-combustion, particularly at high carbon dioxide removal efficiency levels. Heat-integrated configurations nearly double thermodynamic efficiency, especially in the cases of oxyfuel technologies. Therefore, it is recommended that, for the sake of cleaner energy production, both oxyfuel technologies and heat integration should be applied to enhance carbon capture process’ energy efficiency.

Wear and corrosion properties of HVOF sprayed WC-Cr3C2 composite coating for application in polysilicon cyclone separator

The wear and corrosion properties of the cyclone separator play a crucial role for the preparation of high-purity trichlorosilane in the Siemens method polysilicon cold hydrogenation system. In this work, we used fluent simulation technology to determine the optimal spraying process parameters of high velocity oxy-fuel (HVOF) technology, and the Ni60-WC composite coatings with different content of Cr3C2 were prepared on 316L stainless steel surface by using HVOF technology. The microstructure, phase structure and mechanical properties of the coating were characterized, and the wear resistance and corrosion resistance of the coating were studied. By comparing the friction coefficient, wear rate, wear profile and electrochemical polarization and impedance spectrum of the coating, the effects of Cr3C2 content on the microstructure, hardness, wear resistance and corrosion resistance of HVOF sprayed WC composite coating were studied. The results show that the coating prepared by using the simulation parameters are uniform and compact, the coating is tightly bonded to the substrate. The main phases in the coating are WC, W2C and Cr3C2. With the increase of Cr3C2 hard phase, the wear resistance and corrosion resistance gradually improve. Ni60–35WC–20Cr3C2 and Ni60–35WC–30Cr3C2 volume loss rate is the lowest, the friction depth is the shiniest, compared with the substrate, the wear rate is reduced by more than 95 %. Ni60–35WC–20Cr3C2 has the highest corrosion potential, the smallest corrosion current, the smallest corrosion rate and the largest impedance spectrum radius. However, when the content of Cr3C2 reaches 30 %, the corrosion resistance is the worst. Combined with wear resistance and corrosion resistance analysis, the Ni60–35WC–20Cr3C2 coating is selected to provide support for upgrading and prolongating the service life of the cyclone separator.

DEM/CFD simulations of a generic oxy-fuel kiln for lime production

Shaft kilns are the common type of reactor for the production of quicklime. Limestone (CaCO3) particles of cm-size are converted to quicklime (CaO) with the energy provided for calcination by the conversion of a typically gaseous fossil fuel. The CO2 emissions of lime production are severe due to the calcination reaction and the CO2 from combustion. Therefore, methods which pave the way for CO2 capture, such as the Oxy-Fuel technology, are of great interest for the lime industry. This motivates the current contribution, which examines the Oxy-Fuel operation of a single-shaft kiln fired by methane and the results are compared to conventional air operation. A generic, down-scaled version of a kiln has been examined. The height of the kiln is 2.5 m and its diameter is 0.64 m. It contains 23,000 limestone particles with four size classes approximating a polydisperse distribution. The particles are assumed to be spherical. The thermal input of the kiln has been fixed to 80 kW. The evaluation is based on 3D DEM/CFD simulations of the kiln. For simplicity, to avoid the combustion simulation, the exhaust gas produced by the burners of the system is precomputed by Cantera and added to the computational domain as a source term. The source terms are added in two different ways: homogeneously distributed over the cross section at a certain kiln height and spatially distributed at four different locations in a cross section to mimic the presence of burner lances, which are used in industrial kilns.The study shows that the average calcination degree is around 5 % lower for Oxy-Fuel operation compared to the conventional air-fired mode since the increased CO2 concentration hinders the reaction. Further, it is evident that considering a spatially resolved fuel inflow results in an improved degree of product calcination in the order of 5 %, implying that the positioning of burner lances is crucial for the design of industrial kilns.

NOx and N2O emissions from Ca-rich fuel conversion in oxyfuel circulating fluidized bed combustion

A part of Estonia’s power generation is based on oil shale combustion in thermal power plants, resulting in high CO2 and pollutant emissions. The presented paper is a part of long-term experimental work to investigate the combustion of Ca-rich oil shale for air and oxyfuel combustion environments. The experiments were performed in a 60 kWth circulating fluidized bed (CFB) test facility under air, O2/CO2, and O2 with the recycled flue gas (RFG) modes of inlet O2 as vol.% ranging from 21% to 52%, and with RFG of 50% and 87%. The influence of different combustion atmospheres, excess oxygen volumetric ratios in the primary oxidizer (λPr), and dense bed temperatures (TDB), on the total NOx and N2O formations, have been studied in detail.The results show that specific concentrations of NOx (per MJ) were reduced by 14% in O2/CO2 mode, and 22% in O2/RFG compared to air combustion. N2O emissions were increased in OXY21 mode and reduced significantly from 20 mg/MJ to 4 mg/MJ with increasing inlet O2% to 52% under O2/CO2. NOx and N2O emissions were the lowest of all combustion experiments at high inlet O2% with RFG application (OXY87 + RFG). Under all tested atmospheres, NOx emissions were increasing with increasing excess oxygen in the primary oxidizer. N2O enhanced with excess oxygen, accounted for the homogenous gas-phase reaction of volatile-N and the heterogenous reaction of char-N. NOx emissions at low operating TDB were decreasing with increasing bed temperatures and increased at higher TDB > 770 °C in air combustion and TDB > 850 °C in OXY30. N2O emissions were slightly decreased at higher bed temperatures under air and O2/CO2 modes. Combustion efficiency enhanced at higher inlet O2% resulting in lower CO concentrations with reduced fuel burnout, and increased NOx and N2O emissions.Overall, NOx and N2O formations were more affected by the condition of operating parameters under both air and oxyfuel combustion experiments, and the obtained results are giving confidence that oxyfuel technology does not influence the release of nitrogen emissions from oil shale combustion. To lower the cost of CO2 impurities removal, the optimal operating conditions during oil shale CFB combustion can be confirmed after considering the discussed parameters. However, further CO2 purification resulting from oil shale oxyfuel flue gas stream is possibly required.

Techno-Economic Analysis and Life Cycle Assessment of High-Velocity Oxy-Fuel Technology Compared to Chromium Electrodeposition.

Due to the toxicity associated with chromium electrodeposition, alternatives to that process are highly sought after. One of those potential alternatives is High Velocity Oxy-Fuel (HVOF). In this work, a HVOF installation is compared with chromium electrodeposition from environmental and economic points of view by using Life Cycle Assessment (LCA) and Techno-Economic Analysis (TEA) for the evaluation. Costs and environmental impacts per piece coated are then evaluated. On an economic side, the lower labor requirements of HVOF allow one to noticeably reduce the costs (20.9% reduction) per functional unit (F.U.). Furthermore, on an environmental side, HVOF has a lower impact for the toxicity compared to electrodeposition, even if the results are a bit more mixed in other impact categories.

Experimental investigation of single wood particle combustion in air and different O2/CO2/H2O atmospheres

This work aims to obtain experimental data of the combustion behavior of single wood particles under oxyfuel conditions relevant for grate incineration facilities. The objectives are to derive insights on how the application of the oxyfuel technology affects the conditions in the fuel bed in grate firing systems and to generate an experimental data basis for simulation activities. Therefore, combustion experiments of single spherical particles with 4 mm, 6 mm and 8 mm diameter have been performed with varying O2 concentrations (10–50 vol-%) in O2/CO2, O2/CO2/H2O and O2/H2O atmospheres at 900 °C. The duration of the characteristic stages of the thermal conversion process, volatile and char combustion, has been investigated by means of recording videos with distinct frame rate. Additionally, the temperature of the flame as well as the particle has been measured throughout the combustion process. It has been found that the total combustion times of the particles under oxyfuel conditions at 21 vol-% oxygen in dry and wet atmospheres are generally shorter compared to the respective air cases throughout all particle sizes. Increasing the oxygen concentration further reduces the combustion durations. At the same oxygen concentration, the temperature of the volatile flame is increased during oxyfuel combustion compared to air conditions. Comparable particle temperatures during char combustion under air conditions have been measured at 30 vol-% oxygen under oxyfuel conditions. In general, both temperatures increased with rising oxygen concentration and the smallest particles did show the highest values. However, the smallest particles were more strongly affected by the changes in the atmosphere causing higher differences in the measured temperatures. Addition of 40 vol-% steam had a decreasing effect on the temperatures with higher extent at the bigger particle sizes. However, increasing the steam concentration to 70 vol-% at the same oxygen concentration caused higher temperatures.

Ash characterisation formed under different oxy-fuel circulating fluidized bed conditions

The CO2-intensive oil shale power industry accounts for more than 70% of the Estonian energy sector, producing large amounts of ash that are mainly landfilled. Adopting oxy-fuel technology in the Estonian energy sector, in conjunction with CO2 storage, can be a critical tool for reducing carbon footprint. Nevertheless, several differences in ash formation under oxy-fuel conditions can be expected, which can lead to additional ash handling/utilization and related environmental concerns. In this context, the composition of oil shale ash was obtained from a series of combustion experiments in a 60 kWth circulating fluidized bed (CFB) test unit under both air and oxy-fuel combustion regimes studied by means of physical, chemical analysis as quantitative X-ray diffraction and element analysis for ashes from different separation ports. During the experimental work, special attention was given to understanding the impacts of the boiler temperature, recycled flue gas (RFG), and elevated oxygen concentration. As a result, the primary goal of this research is to characterise the ash produced by oxy-fuel combustion of oil shale in order to gain a better understanding of its chemical and mineral compositions, including Ca-Mg silicates and clay minerals, as well as to investigate the behaviour of the formation of free lime and anhydrite, which are the major compounds influencing potential ash utilisation routes. The results show that although the decomposition of calcium carbonates was limited during oxy-fuel combustion because of the high CO2 partial pressure, the contents of secondary silicates and anhydrite were slightly higher. The increased particle temperature and the higher SO2 partial pressure (with RFG) can explain this. The particle size distributions (PSDs) were wider under oxy combustion, and the specific surface area (SSA) in Filter ashes were much higher under elevated inlet O2% atmosphere. Oxy-fuel combustion had no significant impact on the concentration of elements in the ash. Overall, the mineralogy of the ashes formed in air and oxy-fuel combustion environments is similar, yet slight differences exist in the formation of clay minerals in the case of increased oxygen concentrations and with the application of RFG as a result of the increased residence time of the particles.

Numerical simulation on co-firing ultra-low volatile carbon-based fuels with bituminous coal under oxy-fuel condition

The oxy-fuel combustion allows the large-scale CO2 capture from coal-fired power plant, which is an effective approach to reduce CO2 emission and achieve carbon neutrality. The ultra-low volatile carbon-based fuels (LVFs, mainly including gasification residual carbon and pyrolyzed semi-coke) generated from the coal chemical industry cannot be directly disposed effectively, but co-firing with other fuels (bituminous coal for example) is a potential option. However, many nitrogen oxides (NOx) are possibly generated with the absence of combustion stability. Here, the present study aimed at co-combusting LVFs with bituminous coal under oxy-fuel condition to take advantages of oxy-fuel technology to deeply reduce NOx and realize large-scale CO2 capture. The effects of atmosphere and fuel property on co-combustion performances were numerically investigated. The simulation results of co-combustion demonstrate that the NOx emission increases as the mass fraction of bituminous coal falls. The effects of oxidizing gas distribution method on the co-combustion characteristics are highly related to the properties of co-firing fuels. The premixed combustion for bituminous coal/semi-coke co-combustion and in-furnace blending (residual carbon injected from the E layer) for bituminous coal/residual carbon co-combustion could yield less NOx. It is recommended that the oxy-fuel O2 concentration could be kept between 27% and 30% considering the balance between NOx generation and combustion behavior. The 50% bituminous coal/50% semi-coke co-combustion is applicable to co-fire using premixed combustion and appropriate reduction of secondary oxidizing gas flow in the semi-coke layers. The present research will contribute to a further understanding of the efficient and environmentally-friendly utilization of LVFs, as well as better knowledge of CO2 capture and carbon neutrality during electricity generation.

CFD SIMULATION COMPARISON OF BOILER COMBUSTION TEMPERATURE USING CONVENTIONAL COMBUSTION AIR AND OXY-FUEL COMBUSTION

The burning of fossil fuels is the cause of the largest carbon dioxide (CO2) emissions in the world today. CO2 emissions may cause the greenhouse effect and global countermeasures. Boilers are steam generators that use fossil fuels such as coal and natural gas in their environment. The boiler itself is commonly used in power plants and industrial steam generators. In its operation, conventional boilers fueled by natural gas use air for the combustion system where the content of Nitrogen (N2) gas in ordinary air reaches 79% which dissolves CO2 gas in the exhaust gas so that the CO2 gas is carried into the atmosphere. Several technologies that aim to reduce CO2 emissions include pre-combustion, post-combustion, and combustion of oxygen fuel. Numerical methods such as Computational Fluid Dynamics (CFD) are used because the oxy-fuel technology has limited use in the industrial and utility world, and requires large procurement costs. Based on the simulation results, the combustion temperature in the fire system in 1917 o C originating from the combustion system, the resulting temperature is 1857 o C. Even so, the temperature distribution in the oxyfuel combustion system is more even in the combustion system so that the combustion system will be better. This is evidenced by the comparison of temperature comparison graphs on each furnace wall. The result was an increase in the temperature of the wall furnace by 5 o C to 20 o C.

Techno-economic case study on Oxyfuel technology implementation in EAF steel mills – Concepts for waste heat recovery and carbon dioxide utilization

Compared to integrated steel production via blast furnace and basic oxygen furnace, the electric arc furnace route saves energy and carbon dioxide emissions. While the major part of the energy is provided in the form of electric power, a substantial fraction of thermal energy is supplied by the combustion of direct fuels. In the present study, we describe available options for increasing the energy efficiency and cut down on carbon dioxide emissions in electric arc furnace steel mills. Based on these technologies, we develop possible process layouts including the transition to Oxyfuel ladle preheating, on-site utilization of the CO 2 -rich product gas and off-gas heat as well as the recovery of waste heat from the hot gas duct of the electric arc furnace for process steam production. With the aid of an energy system model, a case study is carried out to determine the potential for fuel savings as well as carbon dioxide and waste heat utilization. In a technical assessment, we investigate the relationship between the storage capacities, the carbon dioxide and waste heat utilization ratios as well as the fuel and CO 2 emission savings. The subsequent economic analysis yields the optimum system layout under different framework conditions.

Study of the coolant type influence on the thermal and hydraulic characteristics of cooling channels for high-temperature turbine blades in an oxy-fuel energy system

Electricity consumption by people is increasing every year, followed by an increase in harmful emissions of carbon dioxide into the atmosphere during its generation. A promising solution to the problem of global pollution can be an oxy-fuel technology for energy production. It has been proven that the Allam cycle at an initial temperature of 1100 C is the most efficient oxy-fuel cycle. With a further increase in the initial temperature, the efficiency of this cycle decreases due to an increase in the relative coolant flow rate. This paper discusses the effect of the changeover from carbon dioxide to nitrogen coolant on thermal and hydraulic characteristics of cooling channels for the first-stage blade of a carbon dioxide turbine. We have found that, upon changeover from carbon dioxide to nitrogen cooling, the heat transfer coefficient decreases for a channel with pin intensifiers 1.3 to 1.65 times, for a channel with pin-and-dimple intensifiers, 1.65 to 1.77 times. We have also found that, upon changeover from pin intensifiers to pin-dimple ones, the heat transfer coefficient is increased for a cooling system using carbon dioxide coolant 2.2 to 2.5 times, whereas when using nitrogen coolant, the heat transfer coefficient remains unchanged. It has been also found that, to maintain a constant heat transfer coefficient upon changeover from carbon dioxide to nitrogen coolant, we should provide a 23.6% higher nitrogen flow rates compared to dioxide.

Nd:YVO4 Laser Irradiation on Cr3C2-25(Ni20Cr) Coating Realized with High Velocity Oxy-Fuel Technology—Analysis of Surface Modification

The high-velocity oxy-fuel (HVOF) technique has been extensively used for the deposition of hard metal coatings. The main advantage of HVOF, compared to other thermal spray techniques, is its ability to accelerate the melted powder particles of the feedstock material to a relatively high velocity, leading to good adhesion and low porosity. To further improve the surface properties, a mechanical machining process is often needed; however, a key problem is that the high hardness of the coating makes the polishing process expensive (in terms of time and tool wear). Another approach to achieving surface modification is through interaction with a thermal source, such as a laser beam. In this research, the effects of laser scanning rate, scanning strategy, and number of loop cycles were investigated on an HVOF-coated surface. Cr3C2-25(Ni20Cr) was selected as the coating and Nd:YVO4 as the laser source. The results demonstrate the significance of the starting coating morphology and how the laser process parameters can be tuned to generate different types of modifications, ranging from polishing to texturing.

Experimental study of nitrogen conversion during char combustion under a pressurized O2/H2O atmosphere

Pressurized O2/H2O combustion is a promising oxy-fuel technology for reducing CO2 emissions while improving the overall efficiency of power plants. However, this process is complex, and the associated char-N conversion are not well understood. In the present work, a pressurized horizontal furnace reactor was used to investigate the effects of different factors on the migration and transformation of char-N. Flue gas analysis and X-ray photoelectron spectroscopy were employed to assess the effects of pressure (over the range of 0.1–1.3 MPa), steam concentration (0%–60%) and residence time (60–240 s) on NO emissions and the transformation of char-N. Pressure was found to affect NO emissions and the lowest relative migration of char-N to NO was at 0.4 MPa. With increases in pressure, the proportions of N-5 and N-X groups increased and decreased, respectively·H2O promoted the migration of char-N to NO and the formation of N-X functional groups. As the reaction time prolonged, the proportion of N-5 groups decreased in the early stage of the reaction, that of N-X groups increased in the late stage and N-6 and N-Q groups remained stable.

Techno-Economic Analysis of the Oxy-Fuel Combustion Power Cycles with Near-Zero Emissions

This paper is devoted to improvement of environmental safety in hydrocarbon-firing TPPs. Despite the development of renewable power sources, the number of traditional power production facilities continues its growth. The toxic emission mitigation in traditional TPPs has been deeply investigated, but the problem of greenhouse gas atmospheric emissions is of topical interest. Oxy-fuel technology reduces CO2 emissions and is highly efficient and environmentally safe. Also, it requires relatively low capital investments. Thermal efficiency analysis shows that the Allam cycle facilities have the best efficiency. Their thermodynamic parameters can be optimized with minimal primary costs and capital investments. This newly developed analysis was used to compare the investment efficiency of projects for the buildup of oxy-fuel and combined cycle facilities. Without emission quote payments, the NPV of combined cycle projects is 16% higher, as well as having a lower DPP. The electricity production primary costs in oxy-fuel and combined cycle facilities are similar, which reflects the technologies’ similarity and similar fuel costs. Implementation of carbon dioxide emission quote marketing makes oxy-fuel facilities more investment-attractive. Parametric studies show that when Russia implements CO2 emission quotes compatible with the current EU level, an oxy-fuel facility erection project will be financially reasonable. Thus, it can be concluded that the construction of oxy-fuel power plants is one of the most promising and investment-attractive solutions to reduce CO2 emissions in the energy sector for large industrialized countries. The managerial consequences of their implementation will include the stabilization of greenhouse gas emissions while ensuring the financial stability of the energy industry.

Oxy-fuel Combustion Power Cycles: A Sustainable Way to Reduce Carbon Dioxide Emission

The energy generation from the fossil fuels results to emit a tremendousamount of carbon dioxide into the atmosphere. The rise in the atmosphericcarbon dioxide level is the primary reason for global warming and other cli-mate change problems for which energy generation from renewable sourcesis an alternative solution to overcome this problem. However, the renewablessources are not as reliable for the higher amount of energy production andcannot fulfil the world’s energy demand; fossil fuels will continue to beconsumed heavily for the energy generation requirements in the immediatefuture. The only possible solution to overcome the greenhouse gas emissionfrom the power plant is by capturing and storing the carbon dioxide within thepower plants instead of emitting it into the atmosphere. The oxy-fuel combus-tion power cycle with a carbon capture and storage system is an effective wayto minimize emissions from the energy sectors. The oxy-fuel power cycle canreduce 90–99% of carbon dioxide emissions from the atmosphere. Moreover,the oxy-fuel power cycles have several advantages over the conventionalpower plants, these include high efficiency, lesser plant footprint, much easiercarbon-capturing processes, etc. Because of these advantages, the oxy-fuel combustion power cycles capture more attention. In the last decades, thenumber of studies has risen exponentially, leading to many experimental anddemonstrational projects under development today. This paper reviews theworks related to oxy-fuel combustion power generation technologies withcarbon capture and storage system. The cycle concepts and the advancementsin this technology have been briefly discussed in this paper.

Emission of typical pollutants (NOX, SO2) in the oxygen combustion process with air in-leakages

Oxygen combustion, being an alternative to air combustion, is distinguished in a variety of modern coal management technologies by quick and easy removal of CO2 from the combustion process, which is the key merit of this oxy-fuel technology. The laboratory work conducted so far has not directly addressed the issue of air in-leakages in the oxy-fuel system. The previous studies showed that air in-leakages in the combustion system (both under the air and oxygen regime) occur and affect the combustion process. However, there are no direct research studies on the volume of air in-leakages and their impact on the individual stages of combustion, including the emission of gaseous pollutants. This article focuses on the assessment of the impact of air in-leakages on NOx and SO2 emissions for a single-stage coal-dust combustion system. Moreover, these studies were supplemented with measurements on the rate of devolatilisation of volatile matters and, in particular, on the rate of nitrogen compounds released from fuel. The obtained results of combustion in the oxy-fuel atmosphere with the following air in-leakage levels: 10, 15 and 20% were compared to combustion conditions in the air. Air in-leakages in the oxygen combustion system create an additional flow of oxygen and nitrogen appearing in the combustion area, which affects the course of pollutants and their emission. The conducted studies have shown that when adequate tightness of the combustion system is provided, it contributes to the reduced emission of nitrogen compounds.

Inhibiting in situ phase transition in Ruddlesden-Popper perovskite via tailoring bond hybridization and its application in oxygen permeation

Inhibiting in situ phase transition in Ruddlesden-Popper perovskite via tailoring bond hybridization and its application in oxygen permeation

Oxy-fuel combustion of natural gas: A review

The article compares newly developed methods of natural gas combustion through oxy-fuel technologies. It describes in detail the basic technological differences and ordering of technological parts for five different cycles using carbon dioxide and steam as a working medium in expansion turbines in electricity production. Among the procedures using steam as the working medium, attention is focused on GRAZ and CES cycles. In oxy-fuel procedures utilising carbon dioxide produced by natural gas combustion, the focus is on COOLCEP, MATIANS and COOPERATE cycles. For each cycle described, the respective operating conditions and principles are given. Additionally, detailed process diagrams are also provided. Important advantages of all of these cycles include the possibility of the combustion of not only liquefied natural gas but also other gaseous fossil fuels, whose introduction into production is not very time-consuming, and the possibility of connection to power distribution network within a relatively short period of time.

Creation of energy-efficient and environmentally friendly energy sources on fossil fuels to address global climate issues

For industrialized economies, a strategically important area is developing active methods for industrial use of carbon dioxide emissions to produce marketable products. A rational approach to the problem of clean generation should be based on the complete coordination of the output parameters of the CO2 discharged from the power plant and the input (working) CO2 parameters of the consumer, which will reduce the cost of emissions conditioning, and maintain power plant efficiency. The CO2 parameters from fossil fuel power plants and CO2 consumers’ potential were analyzed for three main indicators most sensitive to power generation: the amount of CO2, operating pressure, and purity considering the level of technological maturity and market attractiveness. Based on the analysis, three types of energy-industrial symbioses were identified with a cost-effective Power Plant – Consumer model without an intermediate unit for matching input and output parameters of CO2 (without a CO2 capture and conditioning system). A hybrid solution combining modern IGCC and the latest thermodynamic cycles based on oxy-fuel technologies is offered as a generalized configuration of the energy part of the promising complex. The concept and key technological solutions of the promising energy-industrial symbiosis “Power Generation Unit – CO2-based production” are being developed at Ural Federal University. Such symbiosis ensures the low-cost supply of CO2 to industrial consumers using mineralization technology. It will allow utilizing not only technogenic carbon but also ash, slag, and construction industry waste to produce marketable products (cement, concrete, and other materials).

Design configurations to achieve an effective CO2 use and mitigation through power to gas

Power to gas energy storage is usually conceived as a carbon utilization technology, as it consumes CO2 for the production of synthetic fuels. However, some authors put in doubt its potential for mitigating global warming, since CO2 is released to the atmosphere when the synthetic fuel is used. In this paper, we demonstrate that power to gas can be an effective mitigation option under certain design configurations. When synthetic fuels are used in the same installation where the CO2 is captured (industry or power plant) then CO2 could be effectively recycled. This “CO2 recycle concept” allows the use of renewable energy to satisfy thermal demands of industry or other sectors avoiding carbon emissions. This proposal is useful for decarbonising industrial processes based on fossil-fuels that cannot be decarbonised by direct renewable electrification. The paper provides key aspects to define a catalytic power-to-gas system where the CO2 is captured (through amine scrubbing or oxyfuel technology) and recycled. It analyses system efficiency, overall emissions and economic feasibility of the concept.