Partial CO2 capture to facilitate cost-efficient deployment of carbon capture and storage in process industries - Deliberations on process design, heat integration, and carbon allocation

Climate change requires that all energy-related sectors reduce drastically their greenhouse gas (GHG) emissions, at a global rate of 1–2\ua0GtCO2 per year, starting now. Process industries, such as the iron and steel, cement, petrochemical, and oil-refining industries, are inherently carbon-intensive, and carbon capture and storage (CCS) is one of the few options available to achieve the required deep reductions in carbon dioxide (CO2) emissions. Despite being technologically mature, CCS has so far not been implemented at the required rates. This is due inter alia to the low value created by CCS for process industries, which is attributed to uncertainties related to carbon pricing and the considerable investments required for CO2 capture installations. This thesis explores the concept of partial carbon capture as an opportunity for the process industry, as part of its transition, to operate in a net-zero emissions framework by the middle of this century. Partial capture is governed by market and site conditions, and aims to capture a designated share of the CO2 emissions from an industrial site, thereby lowering the absolute and specific costs (in€/tCO2) for CO2 capture, as compared to a conventional full-capture system. The thesis elaborates the relevant technical, economic, and policy-related aspects related to facilitating the near-term implementation of carbon capture at industrial sites. These aspects include: 1) the energy- and cost-effective design of solvent-based processes for partial capture, which can lead to capture cost savings of up to 10% for gases with a high CO2 content (>17 vol.%wet); 2) the efficient use of residual heat and existing capacities on-site to power partial capture, which in case studies of an oil refinery and an integrated steel mill, are shown to confer cost savings along the entire CCS chain of 17%–24%; 3) the incorporation of site realities, such as temporal variations in heat availability, into techno-economic assessments; 4) the adaption of policies that address the allocation of carbon emissions reductions to low-carbon products, so that investments in mitigation technologies are incentivized with respect to the ambition level; and 5), the recognition of the rather narrow window of opportunity for partial capture with regard to the lifetime of the existing infrastructure, alternative production and (co-)mitigation technologies, as well as the regional energy and CO2 transport and storage systems. As the title image indicates, the share of carbon extracted from the earth that is sequestered needs to reach 100% by mid-century, in order to limit global warming in line with the targets of the Paris Agreement (i.e., 1.5\ub0C or well below 2\ub0C). Thus, partial capture is only a short-term solution for kick-starting CCS, and it will eventually have to lead to full capture, alternatively full mitigation (e.g., via carbon-free production), or be combined with renewable feedstocks if used in the longer term. Therefore, it is timely for the process industry to apply partial capture and, thereby, ramp up widespread adoption of CCS, so to build up the infrastructure for direct removal of carbon from the atmosphere, which will be required on the gigatonne scale in the second half of the 21st Century

Partial carbon capture – an opportunity to decarbonize primary steelmaking

Climate change requires that all energy-related sectors drastically reduce their greenhouse gas emissions (GHG). To have a high likelihood of limiting global warming to 1.5\ub0C, large-scale mitigation of GHG has to start being implemented and cause emissions to fall well before Year 2030. The process industry, including the iron and steel industry, is inherently carbon-intensive and carbon capture and storage (CCS) is one of the few options available to achieve the required reductions in carbon dioxide (CO2) emissions. Despite its high technological maturity, CCS is not being implemented at the expected rates due inter alia to the low value creation of CCS for process industries, which is often attributed to uncertainties related to carbon pricing and the considerable investments required in CO2 capture. This thesis deals with the concept of partial carbon capture, which is governed by market or site conditions and aims to capture a smaller fraction of the CO2 emissions from an industrial site, thereby lowering the absolute and specific costs (€ per tonne CO2) for CO2 capture, as compared to a conventional full-capture process. Depending on the scale and market conditions these savings hold true especially for a process industry that has large gas flows with concentrations of CO2 ≥20 vol.% and access to low-value heat. Integrated steel mills typically fulfill these conditions.The value of partial capture for the steel industry is assessed in a techno-economic study on the separation of CO2 from the most carbon-intensive steel mill off-gases. The design for partial carbon capture using a 30 wt.% aqueous monoethanolamine (MEA) solvent is optimized for lower cost. Powering the capture process exclusively with excess heat entails a cost of 28–35\ua0(\ub14)\ua0€/tonne CO2-captured and a reduction in CO2 emissions of 19%–\ua043% onsite, depending on design and CO2 source. In contrast, full capture requires external energy to reduce the CO2 site emissions by 76%, entailing costs in the range of 39–54 (\ub15) €/tonne CO2-captured. Furthermore, the use of excess heat has impacts on the cost structure of partial carbon capture, i.e., increasing the ratio of capital expenditures to operational expenditures, as well as on the relationship between carbon and energy intensity for primary steel as an industrial product.The present work concludes that near-term implementation of partial carbon capture in the 2020s will be economically sustainable if average carbon prices are in the range of 40–60 €/tonne CO2 over the entire economic life-time of the partial capture unit (ca. 25 years). Once implemented, partial capture could evolve to full capture over time through either co-mitigation (e.g., with biomass utilization or electrification) or efficiency improvements. Alternatively, partial capture could act as a bridging-technology for new, carbon-free production. In summary, partial carbon capture is found to be readily available and potentially economically viable to initiate large-scale mitigation before Year 2030. Partial capture may represent a starting point for the transition to the carbon-constrained economies of the future in line with the 1.5\ub0C target

Efficient heat integration of industrial CO2 capture and district heating supply

Excess heat from industrial processes can be used for carbon capture and storage (CCS) as well as providing heat to a district heating network, leading to increased energy efficiency and reduction of on-site and/or off-site CO2 emissions. In this work, both options are assessed with respect to economic performance and potential reduction of CO2 emissions. The work includes a generic study based on five heat load curves for each of which three CO2 capture plant configurations were evaluated. The economic assessment indicates that the specific cost of capture ranges from 47-134 €/t CO2 depending on heat profile and capture plant configuration. Having excess heat available during a long period of the year, or having a high peak amount of heat, were shown to lead to low specific capture costs. The paper also includes results of a case study in which the methodology was applied to actual seasonal variations of excess heat for an integrated steel mill located in northern Sweden. Specific capture costs were estimated to 27-44 €/t CO2, and a 36% reduction of direct plant emissions can be achieved if the CO2 capture plant is prioritized for usage of the available excess hea

Capture of CO2 from Steam Reformer Flue Gases Using Monoethanolamine: Pilot Plant Validation and Process Design for Partial Capture

Carbon dioxide (CO2) capture from a slipstream of steam reformer flue gas (18–20 vol %wet CO2) using 30 wt % aqueous monoethanolamine was performed for ∼500 h in a mobile test unit (∼120 kg CO2/h). Specific reboiler duties (SRDs) of 3.6–3.8 MJ/kg CO2 were achieved at 90% capture. The pilot data validate the modeling of off-design partial capture, that is, operation at lower CO2 capture rates (at constant gas flow) than the absorption column was designed to achieve. This paper demonstrates that off-design partial capture enables significant energy savings (SRD, cooling) relative to on-design capture. The accrued savings depend on the column design (packing height, flooding approach) and the feed CO2 concentration. Finally, a concept for stepwise deployment of carbon capture and storage in industries with high-CO2 concentration sources (e.g., steel and cement manufacturing and refining) is introduced. Thanks to its inherent full-capture-ready design, the initial energy-efficient, off-design partial capture operation can be extended to full capture over time

An analysis of a highly compounded two-stroke-cycle compression-ignition engine

Presents an analysis of a compound engine operating with manifold pressures ranging from 60 to 110 lb/sq in. absolute. The effects of engine limits (peak cylinder pressure and turbine-inlet temperature) and component efficiency are discussed. A range analysis is used to evaluate the merit of the engine. The analysis indicates that specific-fuel-consumption values of 0.32 lb/bhp-hr and specific weights of 0.8 lb/bhp are obtainable at high manifold pressures

Plant and system-level performance of combined heat and power plants equipped with different carbon capture technologies

Installing carbon capture and storage (BECCS) capability at existing biomass-fired combined heat and power (bio-CHP) plants with substantial emissions of biogenic CO2 could achieve significant quantities of the negative CO2 emissions required to meet climate targets. However, it is unclear which CO2 capture technology is optimal for extensive BECCS deployment in bio-CHP plants operating in district heating (DH) systems. This is in part due to inconsistent views regarding the perceived value of high-exergy energy carriers at the plant level and the extended energy system to which it belongs. This work evaluates how a bio-CHP plant in a DH system performs when equipped with CO2 capture systems with inherently different exergy requirements per unit of CO2 captured from the flue gases. The analysis is based upon steady-state process models of the steam cycle of an existing biomass-fired CHP plant as well as two chemical absorption-based CO2 capture technologies that use hot potassium carbonate (HPC) and amine-based (monoethanolamine or MEA) solvents. The models were developed to quantify the plant energy and exergy performances, both at the plant and system levels. In addition, heat recovery from the CO2 capture and conditioning units was considered, as well as the possibility of integrating large-scale heat pumps into the plant or using domestic heat pumps within the local DH system. The results show that the HPC process has more recoverable excess heat (∼0.99 MJ/kgCO2,captured) than the MEA process (0.58 MJ/kgCO2,captured) at temperature levels suitable for district heating, which is consistent with values reported in previous similar comparative studies. However, using energy performance within the plant boundary as a figure of merit is biased in favor of the HPC process. Considering heat and power, the energy efficiency of the bio-CHP plant fitted with HPC and MEA are estimated to be 90% and 76%, respectively. Whereas considering exergy performance within the plant boundary, the analysis emphasizes the significant advantage the amine-based capture process has over the HPC process. Higher exergy efficiency for the CHP plant with the MEA capture process (∼35%) compared to the plant with the HPC process (∼26%) implies a relatively superior ability of the plant to adapt its product output, i.e., heat and power production, and negative-CO2 emissions. Furthermore, advanced amine solvents allow the BECCS plant to capture well beyond 90% of its total CO2 emissions with relatively low increased specific heat demand

Excess heat-driven carbon capture at an integrated steel mill – Considerations for capture cost optimization

Primary steelmaking in blast and basic oxygen furnaces is inherently carbon-intensive. Partial capture, i.e., capturing only a share of the CO2, is discussed as an option to reduce the cost of carbon capture and storage (CCS) and to realize a near-term reduction in emissions from the steel industry. This work presents a technoeconomic assessment of partial capture based on amine absorption of CO2. The cost of steam from excess heat is assessed in detail. Using this steam to drive the capture process yields costs of 28–50 €/t CO2-captured. Capture of CO2 from the blast furnace gas outperforms end-of-pipe capture from the combined-heat-and-power plant or hot stove flue gases onsite by 3–5 €/t CO2-captured. The study shows that partial capture driven exclusively by excess heat represents a lower cost for a steel mill owner, estimated in the range of 15–30 €/t CO2-captured, as compared to full capture driven by the combustion of extra fuel. In addition, the full-chain CCS cost (capture, transport and storage) for partial capture is discussed in light of future carbon prices. We conclude that implementation of partial capture in the steel industry in the 2020s is possible and economically viable if policymakers ensure long-term regulation of carbon prices in line with agreed emission reduction targets beyond Year 2030

An Open Educational Resource for minimal online resuscitation training

Van der Baaren, J., Skorning, M., Kalz, M., Kicken, W., & Biermann, H. (2012). An Open Educational Resource for minimal online resuscitation training. Resuscitation, 83 (S1). e111.When a cardiac arrest occurs it is vital that bystanders act immediately. As a minimum bystanders should be able to check consciousness, call 112 and perform chest compression of sufficient depth and speed until an ambulance or other professional support arrives. The majority of people however do not have these skills. Courses in Basic Life Support are available in all European countries on average 2 hour including a practice session. Research shows (1) these courses are effective and both immediate and short-term (4-6 months) retention is high. These courses are however a too time-consuming and costly option when our aim is to train the vast majority of people and maintain their skill level. In this presentation we present a minimal online resuscitation training.This conference contribution is partly sponsored by the European Regional Development Funds, regions of the Euregio Meuse-Rhine and participating institutions of the project

Efficient utilization of industrial excess heat for carbon capture and district heating

Carbon capture and storage (CCS) from fossil and biogenic (BECCS) emission sources is necessary to limit global warming to well below 2\ub0C. The EU as well as Swedish national agencies emphasize the importance of CCS for emission intensive industries. However, the cost of implementing CCS is currently still higher than the cost of emitting CO2 via the EU ETS, for example. To incentivize rapid deployment of CCS, the concept of partial capture has been suggested, i.e. capturing only a fraction of the site emissions to reduce capture cost. Several studies have found that the utilization of excess heat from industrial processes could significantly reduce the capture cost as the heat required (~120\ub0C) may be available in significant quantities. However, available excess heat will not be sufficient to power full capture at most industrial sites. In Sweden, many industries utilize all or part of their excess heat in heat recovery units or in combined heat and power (CHP) plants to produce electricity and deliver heat to municipal district heating (MDH) systems. A broad implementation of CCS will, thus, effect the availability of excess heat for industrial heat and power generation. The future product portfolio of industrial processes with excess heat export and CHP plants can therefore be expected to include not only heat and power production, but also climate services (CCS/BECCS) and grid services (frequency regulation due to intermittent renewables).The aim of this work is to assess partial capture at sites that have access to low-value excess heat to power the capture process, whilst considering competition from using the excess heat for MDH delivery. The work is based on process modelling and cost estimation of CO2 capture processes using amine absorption for two illustrative case studies, a refinery and a steel mill, which both currently use excess heat for MDH. The main focus is on investigating how seasonal variations in the availability of excess heat as well as the demand of district heating impact cost-efficient design and operation of partial capture at industrial sites. A challenge when utilizing excess heat in connection to a process connected to a district heating system is that the heat source which can be used to power part of the capture process will exhibit seasonal availability, and thus may inflict extra cost for the CCS plant not running at full load, and therefore may counteract the economic motivation for partial capture. To prevent this, heat integration between CCS and municipal district heating is investigated, for example by utilizing heat from the CO2 compression so that low-pressure steam is released from MDH to provide heat to capture CO2 whilst maintaining MDH supply. The design of the amine absorption capture process will have to handle significant load changes and still maintain high separation efficiency within hydrodynamic boundaries of the absorber and stripper columns. The cost of such operation will depend on the solvent circulation flows, the number of absorber columns (including packing and liquid collectors/distributors) and capacity of solvent buffer tanks for storing unused solvent during the winter season. Assuming that a constant amount of CO2 is avoided, the avoidance cost of CCS based on excess heat with seasonal heat load variations is compared to the avoidance cost of CCS based on the use of external fuel to achieve a constant heat load to the reboiler