| 41. |
- Beiron, Johanna, 1992, et al.
(författare)
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Integration of CCS in Combined Heat and Power Plants in a City Energy System
- 2022
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Ingår i: Proceedings of the 16th Greenhouse Gas Control Technologies Conference (GHGT-16) 23-24 Oct 2022. - : Elsevier BV.
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Konferensbidrag (refereegranskat)abstract
- Carbon dioxide removal (CDR) is expected to play an important role in climate change mitigation. Bio-energy carbon capture and storage (BECCS) is a form of CDR discussed in the Swedish district heating sector where large-scale point sources of biogenic CO2 emissions are found. This work investigates the retrofit of CO2 capture processes to combined heat and power (CHP) plants in a city energy system context, to examine the impact on CHP plant energy output and city energy balances, and the cost-optimal way to integrate and operate the capture processes. An energy system optimization model is applied to a case study of the city Västerås, Sweden, with scenarios involving the retrofit to two existing CHP plants in the city of either a heat-driven (MEA) or electricity-driven (HPC) carbon capture process. The results show that it is possible to retrofit the CHP plants with either of these options without significantly impacting the district heating system operation or the marginal costs of electricity and district heating. The MEA process mainly causes a reduction in district heating output (up to 30% decrease on an annual basis), which can be partly offset with heat recovery from the capture unit, or increased utilization of the CHP plants (if possible). The electrified HPC process does not impact the CHP plant steam cycle, but implies increased import of electricity to the city (up to 44% increase) compared to a reference scenario.
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| 42. |
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| 43. |
- Berggren, Mårten, et al.
(författare)
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Biomass co-firing potentials for electricity generation in Poland—Matching supply and co-firing opportunities
- 2008
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Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 1873-2909 .- 0961-9534. ; 32:9, s. 865-879
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Tidskriftsartikel (refereegranskat)abstract
- As part of the European Union (EU) accession treaty, Poland is obliged to increase the share of renewable electricity production to 7.5% by 2010 (from a present share of about 2% in 2002). Most of this increase is expected to be covered by biomass-based electricity generation. This paper investigates the potential for co-firing of biomass and coal in the Polish power-generation system. More specifically, this study focuses on matching potentials in biomass supply with opportunities for co-firing biomass in existing coal-fired power plants. Available estimates of biomass supply and information on the power plant infrastructure are used as input for modelling the co-firing potential for each of the 16 regions in Poland ("Voivodship"). The modelling also gives the additional cost of the electricity and the CO2-avoidance cost for the co-firing. The result shows a potential of electricity produced from biomass in co-firing of 1.6-4.6% (2.3-6.6 TWhe) of the total electricity production in 2010. Adding this potential to the existing production of about 2% electricity from renewable energy sources (RES-E) gives an overall contribution of RES-E in the range 3.6-6.6%. The additional cost for the implementation of co-firing is less than €20 per MWhe (the average electricity price in Poland in 2003 was €96 per MWhe) corresponding to a CO2-avoidance cost of less than €20 per tonne CO2. In summary it can be concluded that although co-firing can serve as a low-cost option for near-term increase of RES-E, there is still an additional 0.9-3.9% of other RES-E production required to be developed to reach the 2010 target of 7.5% RES-E. The results call for quick action with respect to implementation of co-firing, if Poland should have any chance to reach the RES-E target by 2010.
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| 44. |
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| 45. |
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| 46. |
- Berndes, Göran, 1966, et al.
(författare)
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Strategies For 2nd Generation Biofuels In Eu - Co-firing to stimulate feedstock supply development and process integration to improve energy efficiency and economic competitiveness
- 2010
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Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 1873-2909 .- 0961-9534. ; 34:2, s. 227-236
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Tidskriftsartikel (refereegranskat)abstract
- The present biofuel policies in the European Union primarily stimulate 1st generation biofuels that are produced based on conventional food crops. They may be a distraction fromlignocellulose based 2nd generation biofuels – and also from biomass use for heat and electricity – by keeping farmers’ attention and significant investments focusing on firstgeneration biofuels and the cultivation of conventional food crops as feedstocks. This article presents two strategies that can contribute to the development of 2nd generation biofuels based on lignocellulosic feedstocks. The integration of gasification-based biofuel plants in district heating systems is one option for increasing the energy efficiency and improving the economic competitiveness of such biofuels. Another option, biomass co-firing with coal,generates high-efficiency biomass electricity and reduces CO2 emissions by replacing coal. It also offers a near-term market for lignocellulosic biomass, which can stimulate development of supply systems for biomass also suitable as feedstock for 2nd generation biofuels. Regardless of the long-term priorities of biomass use for energy, the stimulation of lignocellulosic biomass production by development of near term and cost-effective markets isjudged to be a no-regrets strategy for Europe. Strategies that induce a relevant development and exploit existing energy infrastructures in order to reduce risk and reach lower costs, are proposed an attractive complement the present and prospective biofuel policies.
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| 47. |
- Berntsson, Thore, 1947, et al.
(författare)
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Towards Sustainabel Oil Refinery - Pre-study for larger co-operation project
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In this report, the Chalmers EnergiCentrum (CEC) presents the results of a pre-study commissioned by Preem relating to the effective production of future vehicle fuels.This pre-study was made up of three studies focusing on energy streamlining, the utilisation of waste heat and carbon-dioxide separation and biorefinement relating to the gasification and hydration of vegetable oils. One of the common starting points for these studies was the current situation at the Preem refineries in Göteborg and Lysekil from where the measurement data were obtained and analysed. The report summarises the knowledge situation based on current research in the individual technical fields. The results present some interesting future opportunities for developing the sustainable production of future vehicle fuels. The sections vary, as the areas that have been examined differ and the sections have been written by different people. The reports ends with some joint conclusions and a number of questions which could be included and answered in a more extensive future main study, as part of a developed research partnership between Preem and the Chalmers University of Technology. The preliminary results of this work were analysed with the client at workshops on 1 October and 29 November 2007. The report is written in English combined with an extensive summary in Swedish including a proposal on a future main study. The study was conducted by the Chalmers EnergiCentrum (CEC), in collaboration with a number of researchers in the CEC’s network. They included Thore Berntsson, Jessica Algehed, Erik Hektor and Lennart Persson Elmeroth, all from Heat and Power Technology, Börje Gevert, Chemical and Biological Engineering, Tobias Richards, Forest Products and Chemical Engineering, Filip Johnsson and Anders Lyngfelt, Energy Technology, and Per-Åke Franck and Anders Åsblad, CIT Industriell Energianalys AB. The client, Preem, was represented by Bengt Ahlén, Sören Eriksson, Johan Jervehed, Bertil Karlsson, Gunnar Olsson, Ulf Kuylenstierna, Stefan Nyström, Martin Sjöberg and Thomas Ögren. Tobias Richards was responsible for compiling the report and Bertil Pettersson was the project manager.
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| 48. |
- Biermann, Max, 1989, et al.
(författare)
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Capture of CO2 from Steam Reformer Flue Gases Using Monoethanolamine: Pilot Plant Validation and Process Design for Partial Capture
- 2022
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Ingår i: Industrial & Engineering Chemistry Research. - : American Chemical Society (ACS). - 1520-5045 .- 0888-5885.
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 49. |
- Biermann, Max, 1989, et al.
(författare)
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Carbon Allocation in Multi-Product Steel Mills That Co‐process Biogenic and Fossil Feedstocks and Adopt Carbon Capture Utilization and Storage Technologies
- 2020
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Ingår i: Frontiers in Chemical Engineering. - : Frontiers Media SA. - 2673-2718. ; 2
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Tidskriftsartikel (refereegranskat)abstract
- This work investigates the effects of carbon allocation on the emission intensities of low-carbon products cogenerated in facilities that co‐process biogenic and fossil feedstocks and apply the carbon capture utilization and storage technology. Thus, these plants simultaneously sequester CO2 and synthesize fuels or chemicals. We consider an integrated steel mill that injects biomass into the blast furnace, captures CO2 for storage, and ferments CO into ethanol from the blast furnace gas. We examine two schemes to allocate the CO2 emissions avoided [due to the renewable feedstock share (biomass) and CO2 capture and storage (CCS)] to the products of steel, ethanol, and electricity (generated through the combustion of steel mill waste gases): 1) allocation by (carbon) mass, which represents actual carbon flows, and 2) a free-choice attribution that maximizes the renewable content allocated to electricity and ethanol. With respect to the chosen assumptions on process performance and heat integration, we find that allocation by mass favors steel and is unlikely to yield an ethanol product that fulfills the Renewable Energy Directive (RED) biofuel criterion (65% emission reduction relative to a fossil comparator), even when using renewable electricity and applying CCS to the blast furnace gas prior to CO conversion into ethanol and electricity. In contrast, attribution fulfills the criterion and yields bioethanol for electricity grid intensities 2/kWhel without CCS and yields bioethanol for grid intensities up to 800 gCO2/kWhel with CCS. The overall emissions savings are up to 27 and 47% in the near-term and long-term future, respectively. The choice of the allocation scheme greatly affects the emissions intensities of cogenerated products. Thus, the set of valid allocation schemes determines the extent of flexibility that manufacturers have in producing low-carbon products, which is relevant for industries whose product target sectors that value emissions differently. We recommend that policymakers consider the emerging relevance of co‐processing in nonrefining facilities. Provided there is no double-accounting of emissions, policies should contain a reasonable degree of freedom in the allocation of emissions savings to low-carbon products, so as to promote the sale of these savings, thereby making investments in mitigation technologies more attractive to stakeholders.
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| 50. |
- Biermann, Max, 1989, et al.
(författare)
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Efficient utilization of industrial excess heat for carbon capture and district heating
- 2020
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Carbon capture and storage (CCS) from fossil and biogenic (BECCS) emission sources is necessary to limit global warming to well below 2°C. 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°C) 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.
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