Carbon Recycling: An Alternative to Carbon Capture and Storage

Limits to Paris compatibility of CO2 capture and utilization

Will blue hydrogen lock us into fossil fuels forever?

Net-zero emissions chemical industry in a world of limited resources

Carbon Capture, Usage and Storage – in short CCUS, is not a new term in the current industrial environment. It is being discussed widely at all industrial forums, across all countries, big or small, to control pollution to ensure a healthy and happy life for all. There have been attempts and studies over last 50 years to capture carbon dioxide from the environment to avoid pollution and control global warming scenario. Many technologies have been in use for carbon capture, across the globe, some in large scale and others confined to local areas. It is expensive but very much essential – it is a goal set by WHO/UNO/European Commission – to clean the environment off CO2 gases, use it for alternative purposes or store it for future action. According to International Energy Agency (IEA), we must capture around 100 billion tons of CO2 by 2060 to meet International Global Warming and Energy goals. It is a huge goal and is a very expensive goal to achieve. All big countries who impact the environment in a huge way through their industries shall come forward for a collaboration to prepare a robust plan, pump-in money, monitor and control the processes, to achieve the goal. There is an estimate that US emitted around 5,1 mln t of CO2 in 2019 whereas Global estimate emitted around 33 mln t. These are very huge numbers and hence Global monitoring is very essential to control emission and safe storage and disposal. It is important to understand that Carbon Capture (CC), Carbon Capture and Use (CCU) and Carbon Capture and Storage (CCS) are three different terms. CC, CCU and CCS are combinedly termed as CCUS. CC is to capture carbon from various sources – fuel gas, fossil fuels, petroleum products, flares from refineries and power plants etc. Usage of the captured carbon in the form of carbon dioxide (CO2) is CCU and this is an important long-term vision by any government to ensure it is being used meaningful to avoid negative impact on climate. CCS is storage of the captured carbon quickly so that it does not impact the environment as a greenhouse gas and at the same time, it can be used later. Another term which is frequently used is Net Zero CO2. It is defined as follows: Any CO2 released into the atmosphere from a human activity shall be balanced by an equivalent amount being removed, either by nature-based solutions (including afforestation, reforestation or other changes in land use) or technological solutions that stores CO2 captured directly or indirectly, permanently. Net Zero CO2 is very important, unless this is achieved, CCUS goal cannot be achieved to control climate change. This write-up provides an insight into the following topics:  What is CCUS?  Why is it important?  Steps to CCUS;  CAPEX and OPEX involved.

Low-carbon production of iron and steel: Technology options, economic assessment, and policy

Towering 650 feet over the sea surface and spouting an impressive burning flare, it would be easy to mistake the Sleipner West gas platform for an environmental nightmare. Its eight-story upper deck houses 200 workers and supports drilling equipment weighing 40,000 tons. Located off the Norwegian coast, it ranks among Europe’s largest natural gas producers, delivering more than 12 billion cubic feet of the fuel annually to onshore terminals by pipeline. Roughly 9% of the natural gas extracted here is carbon dioxide (CO2), the main culprit behind global warming. But far from a nightmare, Sleipner West is actually a bellwether for environmental innovation. Since 1996, the plant’s operators have stripped CO2 out of the gas on-site and buried it 3,000 feet below the sea floor, where they anticipate it will remain for at least 10,000 years. We believe [CCS] is a viable way to cut global warming pollution. . . . We have the knowledge we need to start moving forward. –David Hawkins, Natural Resources Defense Council Operated by StatoilHydro, Norway’s largest company, Sleipner is among the few commercial-scale facilities in the world today that capture and bury CO2 underground. Many experts believe this practice, dubbed carbon capture and storage (sometimes known as carbon capture and sequestration, but in either case abbreviated CCS), could be crucial for keeping industrial CO2 emissions out of the atmosphere. Sleipner injects 1 million tons of CO2 annually into the Utsira Formation, a saline aquifer big enough to store 600 years’ worth of emissions from all European power plants, company representatives say. With mounting evidence of climate change—and predictions that fossil fuels could supply 80% of global energy needs indefinitely—the spotlight on CCS is shining as brightly as the Sleipner flare. A panel of experts from the Massachusetts Institute of Technology (MIT) recently concluded that CCS is “the critical enabling technology to reduce CO2 emissions significantly while allowing fossil fuels to meet growing energy needs.” The panel’s views were presented in The Future of Coal, a report issued by MIT on 14 March 2007. Environmental groups are split on the issue. Speaking for the Natural Resources Defense Council (NRDC), David Hawkins, director of the council’s Climate Center and a member of the MIT panel’s external advisory committee, says, “We believe [CCS] is a viable way to cut global warming pollution. . . . We have the knowledge we need to start moving forward.” Other environmental groups, including the World Resources Institute, Environmental Defense, and the Pew Center on Global Climate Change, have also come out in support of CCS. These groups view CCS as one among many alternatives (including renewable energy) for reducing CO2 emissions. Greenpeace is perhaps the most vocal critic of CCS. Truls Gulowsen, Greenpeace’s Nordic climate campaigner, stresses that CCS deflects attention from renewable energy and efficiency improvements, which, he says, offer the best solutions to the problem of global warming. “Companies are doing a lot of talking about CCS, but they’re doing little to actually put it into place,” he says. “So, they’re talking about a possible solution that they don’t really want to implement now, and at the same time, they’re trying to push for more coal, oil, and gas development instead of renewables, which we already know can deliver climate benefits.”

Carbon dioxide (CO2) emitted into the atmosphere by fossil fuel combustion is the most significant greenhouse gas contributing to climate change. Use of coal alone accounts for 43% of global CO2 emission in 2010. As the most abundant, the most reliable and cheap energy source, coal will continue to play a significant role in the world’s economy and improving people’s standard of living in particular in the developing countries. With the strong demand for coal, there is no doubt that the CO2 emissions will continue to rise. On May 9, 2013, the daily mean concentration of carbon dioxide in the atmosphere of Mauna Loa, Hawaii, surpassed 400 ppm for the first time since measurements began in 1958. The rate of increase is ca 2.1 ppm per year during the last 10 years. Without significant reduction of CO2 emissions, it is unlikely to limit the long-term concentration of greenhouse gasses to 450 ppm CO2 by 2050. Carbon capture and storage (CCS) is a process CO2 is separated from large point sources, including fossil fuel power plants, and transported to a disposal site, normally an underground geological formation, for permanent storage. It is generally agreed that CCS is the only technology available to make deep cuts in greenhouse gas emissions while still using fossil fuels and much of today’s energy infrastructure. According to the International Energy Agency (IEA), CCS will account for 19% of total emissions reduction if the global CO2 emissions are halved by 2050. However, looking back, there has been great uncertainty surrounding the commercial implementation of CCS technologies. Despite the fact that all the necessary components of CCS process are commercially available, the question about the large scale CO2 storage remains. The progress towards the commercial deployment of CCS technologies is slow. A number of factors contribute to a slow progress of CCS development. Firstly, the CCS projects are very costly. Most studies estimate that CCS will add more than 50% to the cost of electricity from coal. The costs for the first commercial CCS plants will be much higher than the following projects. No one wants to take the risk to be the first one. Secondly, CCS depends on the political polices to drive it. There is no a legally binding agreement on the emissions reduction applied to all countries and there is no market for CCS. Last but not the least, CCS depends on the government support. In an unfavourably financial environment, the R & D spending is expected to decline. Recently Australian government has announced a budget cut of $500 million over three years to its national CCS flagship program, almost one third of the total funding from the federal government. The Australia’s opposition party has even pledged to abolish the carbon tax if elected in September 2013. So, what is the future for CCS? It is a difficult question to answer. A critical issue is who is going to pay for the development of CCS. It should be pointed out that the majority of the upcoming projects use captured CO2 for enhanced oil recovery. The reason for that is EOR can facilitate the development of CCS by improving the financial viability of the CCS, building the infrastructure required for CCS, and developing capability along the supply chain. An increase in EOR projects reflexes the importance of CO2 utilisation. Carbon Capture, Utilisation and Storage (CCUS) is gaining increased attention in particular in USA and China. It is unlikely for the developing counties to deploy the CCS technologies with financial support from the government alone. In these countries the priorities are to sustain the economic growth and improve people’s living standard. To move CCS forward, it is important to realise the challenges facing the CCS development and make appropriate adjustment based on the political and economic realities. Considering that the funding on the development of CCS is limited, the international R & D program needs to be well coordinated and have the right focus and the right scale to avoid unproductive overlap between demonstration projects and ensure that limited resources are spent wisely to achieve the highest benefits. As a researcher working on CO2 capture, I am glad to

Kicking the Oil Addiction

Capturing rogue carbon

Carbon capture and storage (CCS) demonstration projects in Canada

Qatar is the biggest exporter of liquefied natural gas, LNG, in the world and is a main oil-producing member of The Organization of Petroleum Exporting Countries, OPEC. A fossil fuel-based industry emerged around the ports of Ras Laffan and Mesaieed, Qatar's industrial cities, perusing industrial diversity and maximising the huge fossil fuel reserves that serve as the primary feedstock for the industrial sector. LNG, crude oil, and petroleum products has given Qatar a per capita GDP that ranks among the highest in the world with the lowest unemployment. This also has given Qatar a per capita CO 2 emissions among the highest in the world. A recent report from The World Health Organisation, stated that the capital of Qatar, Doha, is one of the world's most polluted cities and its air ranked the 12th highest average levels of small and fine particles which are particularly dangerous to health [1]. The people and wise leadership of Qatar recognizes the significance of the problem and made environmental development one of the four pillars of Qatar National Vision 2030. The vision places environmental preservation for Qatar's future generations at the forefront. Qatar Carbonates and Carbon Storage Research Centre is an example demonstrating Qatar's commitment to preserve the envioronment by investigating and implementing key technologies such as carbon capture and storage (CCS) to address the next step in climate change. CCS in deep saline aquifers is an important process for CO 2 reduction on industrial scales. The aim of CCS is to safely sequester CO 2 generated from stationary sources, such as power-plants, into aquifers and depleted oil reservoirs. It is considered a valuable option to reduce greenhouse gases and has been proposed as a practical technology to tackle climate change [2–4]. The importance of CCS as a key option to mitigate CO 2 emissions and combat climate change has been highlighted also in a report by the International Energy Agency (IEA) and suggests that CCS could contribute to a 17% reduction in global CO 2 emissions by 2035 [5]. Previously, carbon dioxide injection into the subsurface has mainly been used for enhanced oil recovery (EOR) purposes. That gave rise to Carbon capture, utilization and storage (CCUS) processes in mature oil reservoirs where CO 2 is first used to enhance oil recovery and then ultimately stored in the reservoir. The incremental hydrocarbon recoveries associated with CCUS make it more attractive to implement compared to CCS. It have significant energy, economic and environmental benefits and is considered an important component in achieving the widespread commercial deployment of CCS technology. Residual trapping of CO 2 through capillary forces within the pore space of the reservoir is one of the most significant mechanisms for storage security and is also a factor determining the ultimate extent of CO 2 migration within the reservoir. Observations and modelling have shown how capillary, or residual, trapping leads to the immobilisation of CO 2 in saline aquifer reservoirs, limiting the extent of plume migration, enhancing the security and capacity of CO 2 storage [6,7]. In contrast, carbonate hydrocarbon reservoirs are characterised by a mixed-wet state in which the capillary trapping of nonpolar fluids have been observed to be significantly reduced relative to trapping in rocks typical of saline aquifers unaltered by the presence of hydrocarbons [8,9]. There are, however, no observations characterising the extent of capillary trapping that will take place with CO 2 in mixed-wet carbonate rocks, the same rock type found in Qatar's subsurface geological formations and many other giant oil reservoirs in the Middle East that hold most of the oil in the world [10, 11]. Experimental tests of CO 2 and brine in carbonate rocks at reservoir conditions are very challenging due to the complex and reactive nature of carbonates when dealing with corrosive fluids pair of CO 2 and brine. In this study, we compare residual trapping efficiency in water-wet and mixed-wet carbonates systems on the same rock sample before and after wettability alteration by aging with oil mixture of Arabian medium crude oil. The experimental work was conducted using a state of the art multi-scale imaging laboratory (core and pore scale) developed at Imperial College London designed to characterise reactive transport and multiphase flow, with and without chemical reaction for CO 2 -brine systems in both sandstone and carbonate rocks at reservoir conditions [12]. The flow loop included stir reactor to equilibrate rock with fluids, high precision pumps, temperature control, the ability to recirculate fluids for weeks at a time and an x-ray CT scanner and micro x-ray scanner for in situ saturation monitoring. The wetted parts of the flow-loop are made of anti-corrosive material that can handle co-circulation of CO 2 and brine at reservoir conditions with the ability to preserve the rock sample from reacting to carbonic acid. We report the initial-residual CO 2 saturation curve and the resulting parameterisation of hysteresis models for both water-wet and mixed-wet systems. A novel core-flooding approach was used, making use of the capillary end effect to create a large range in initial CO 2 saturation in a single core-flood. Upon subsequent flooding with CO 2 -equilibriated brine, the observation of residual saturation corresponded to the wide range of initial saturations before flooding resulting in a rapid construction of the initial residual curve. Observations were made on a single Estaillades limestone core sample. It was made first on its original water-wet state, then were measured again after altering the wetting properties to a mixed-wet system. In particular, CO 2 trapping was characterized before and after wetting alteration so that the impact of the wetting state of the rock is observed directly on both core and pore scales. A carefully designed wettability alteration programme was designed in this study to replicate a mixed-wet carbonate system similar to those found in Qatari oil reservoirs. At the pore level, oil can precipitate asphaltene and other heavy components after long exposure with the rock changing the wetting state of the surface to oil-wet. A mixture of the evacuated crude oil with an organic precipitant, n-heptane, was used to deposit a stable oil-wet film. The precipitant substituted some of the evaporated and oxidised light hydrocarbon originally existed in the crude and deposited asphaltene to generate a stable strongly oil-wet film layer. Filtration experiments were carried out to sensibly precipitate enough asphaltene for a stable and strong oil-wet film without over precipitating and causing fine migration that can damage the core sample. The weight fraction of asphaltene precipitated with different fractions of crude-precipitant mixtures were measured. The diluent consisted of toluene as the solvent and heptane as the precipitant. 40 ml of the diluent was thoroughly mixed with 1 ml of Arabian Medium crude oil at 11 different precipitant/solvent volume ratios ranging from 0–100% at 10% increments and then left in the dark for 48 hours to allow the system to come to equilibrium. The mass of precipitated asphaltenes was measured in each mixture by vacuum filtration using a 0.45 micron polytetrafluoroethylene hydrophobic filter paper (Millipore) and evaporation of any remaining liquid oil from the filter paper. No asphaltene was precipitated at low precipitant volume fraction and only above the onset of precipitation, a linear relationship was seen between the wt% precipitated asphaltenes and the volume % of the precipitant in the mixture. The onset for asphaltene precipitation for an oil mixture of Arabian Medium crude oil and heptane alone without solvent was calculated at the onset using the volume fractions of the components with the mixing rule. The sample's wettability was altered to a mixed-wet using the appropriate oil mixture as measured using the filtration test and the oil was then removed from the sample by CO 2 enhanced oil recovery injected above the minimum miscibility pressure. This allowed for producing unique dataset and a great complement to the more theoretical analysis. That is if we make a surface oil-wet (to water), how does it behave in the presence of a gas. Here we show that residual CO 2 trapping in mixed-wet carbonate rocks characteristic of hydrocarbon reservoirs is significantly less than trapping in water-wet systems characteristic of saline aquifers. We found that in the native water-wet state of the carbonate sample, the extent of trapping of CO 2 and N 2 were indistinguishable, consistent with past studies of trapping and multiphase flow properties in water-wet sandstones [13, 14]. After alteration of the wetting state of the same rock sample with oil, the residual trapping of N 2 was reduced compared to the amount in the pre-altered rock. Surprisingly, the trapping of CO 2 was reduced even further. The unique results were complemented with pore scale observations to investigate the balance of interfacial tensions and contact angles in three-phase flow. Our results show that one of the key processes for maximising CO 2 storage capacity and security is significantly weakened in hydrocarbon reservoirs relative to saline aquifers. We anticipate this work to highlight a key issue for the early deployment of carbon storage – that

Carbon dioxide (CO2) is an important material in many industries but is also representing more than 80% of greenhouse gases (GHGs). Anthropogenic carbon dioxide accumulates in the atmosphere through burning fossil fuels (coal, oil, and natural gas) in power plants and energy production facilities, and solid waste, trees, and other biological materials. It is also the result of certain chemical reactions in different industry (e.g., cement and steel industries). Carbon capture and storage (CCS), among other options, is an essential technology for the cost-effective mitigation of anthropogenic CO2 emissions and could contribute approximately 20% to CO2 emission reductions by 2050, as recommended by International Energy Agency (IEA). Although CCS has enormous potential in numerous industries and petroleum refineries due their large CO2 emissions, a significant impediment to its utilization on a large scale remains both operating and capital costs. It is possible to reduce the costs of CCS for the cases where industrial processes generate pure or rich CO2 gas streams, but they are still an obstacle to its implementation. Therefore, significant interest was dedicated to the development of improved sorbents with increased CO2 capacity and/or reduced heat of regeneration. However, recent results show that phase equilibria, transport properties (e.g., viscosity, diffusion coefficients, etc.) and other thermophysical properties (e.g., heat capacity, density, etc.) could have a significant effect on the price of the carbon. In this context, we focused our research on the phase behavior of physical solvents for carbon dioxide capture. We studied the phase behavior of carbon dioxide and different classes of organic substances, to illustrate the functional group effect on the solvent ability to dissolve CO2. In this chapter, we explain the role of phase equilibria in carbon capture and storage. We describe an experimental setup to measure phase equilibria at high-pressures and working procedures for both phase equilibria and critical points. As experiments are usually expensive and very time consuming, we present briefly basic modeling of phase behavior using cubic equations of state. Phase diagrams for binary systems at high-pressures and their construction are explained. Several examples of phase behavior of carbon dioxide + different classes of organic substances binary systems at high-pressures with potential role in CCS are shown. Predictions of the global phase diagrams with different models are compared with experimental literature data.

Integrated assessment model simulations are often cited when recommending  carbon capture and storage (CCS) as an important component of decarbonization for the power industry. Here, we use a simplified setting to analyze the economic sensitivity of post-combustion fossil-fuel CCS to a set of parameters including fuel costs, electricity prices, and subsidies. We formulate the model to represent coal and natural gas power plants fitted with CCS. We then ask what level of subsidies are necessary to make CCS profitable for the operator. Our results indicate that: (1) With current US subsidies and under most market conditions, CCS is much more profitable when injected carbon dioxide is used for enhanced oil recovery than for geologic storage. For this reason, CCS is likely to continue to be used for enhanced oil recovery and so will increase system-wide emissions because the combustion of the oil produced emits more carbon dioxide than is injected to produce the oil. (2) CCS subsidies can drop the marginal cost of electricity generation to near zero, making CCS fossil fuel electricity competitive with renewables in the power market, even as these power plants continue to emit a portion of their carbon dioxide. (3) With CCS subsidies, coal-fired power production can become more profitable than natural gas power because coal produces more carbon dioxide and hence harvests more subsidies. To be profitable, natural gas power plants require higher tax subsidies than coal, and their cash flow is more sensitive to changes in the price of power, which disadvantages natural gas plants when coupled to CCS. (4) In the US, subsidies are provided per ton of carbon dioxide stored rather than per ton of carbon dioxide kept out of the atmosphere. Our calculations demonstrate how the effective subsidy per ton of emissions avoided is more than the subsidy paid per ton of carbon dioxide captured unless the grid is completely decarbonized, because of the energy penalty of CCS. (5) The value of natural gas CCS for reducing emissions diminishes as the carbon intensity of the local power grid increases. We recommend that these insights be used in integrated assessment models such that these models more accurately represent the influence of market dynamics and provide better insights for reducing emissions. 

Carbon capture and storage, bio-energy with carbon capture and storage, and the escape from the fossil-fuel lock-in

Focus on Carbon Capture and Storage (CCS) has grown over the past decade with recognition of CCS’s potential to make deep CO2 emission reductions and that fossil fuels will continue to be needed to supply much of the world's energy demands for decades to come. How CCS will compare to other options in the future depends critically on the cost of CCS (the focus of this paper) and resolution of barriers to CCS deployment, as well as costs and barriers for other emission reduction options. This paper provides a comparison of the cost of electricity of five power generation options – coal and gas Combined Cycle Gas Turbine (CCGT,) with and without CCS and nuclear – and shows regions of carbon price and fuel prices where each can be economically viable. Current cost estimates for coal CCS for Nth-of-a-kind power generation plant are in the 60-100 $/ton of CO2 avoided – higher than some of the earlier CCS estimates, and higher than the generally accepted range of expected carbon prices in the next two decades. The high cost of coal CCS suggests that:Gas based power generation is much more economical than coal CCS at carbon prices below 60-100 $/ton CO2.Even after carbon prices reach 60-100 $/ton CO2, gas CCS produces lower cost electricity than coal CCS as long as natural gas prices remain below 9 $/MBTU.Nuclear has a lower cost of electricity than coal CCS. Although Coal or Gas CCS is unlikely to be economical in power generation over the next two decades, subsidized demonstrations of CCS are likely to occur. In addition, components of CCS technologies will continue to be economically practiced in early use segments such as natural gas processing and Enhanced Oil Recovery (EOR) operations. In this paper, we share ExxonMobil’s experience at LaBarge in using CO2 from a natural gas facility for EOR use – the single largest CO2 capture site for sub-surface injection in the world today. In the natural gas processing industry, CO2 separation cost is a fraction of the cost of CO2 capture in power generation due to its higher gas pressure, and the CO2 separation is typically necessary to monetize the natural gas resource. In contrast, CCS for most refinery and industrial emissions is expected to be significantly more costly than power generation because the CO2 streams are typically smaller scale and more distributed than those from large power plants. Realistic estimates of cost for CCS, as well as for other greenhouse gas (GHG) mitigation options, are an important input for focusing research, development and demonstration (RD&D) addressing barriers to applications that show the greatest promise, and development of sound policy.