二氧化碳直接空气捕获装置的技术经济评价(英).pdf
ect Keywords: Carbon dioxide (CO 2 ) Direct air capture (DAC) Carbon capture and utilisation (CCU) Negative emission technology (NET) Economics C) s in energy in a neutral or negative greenhouse gas emission energy system, and influence policy makers. In this formed, wherein, DAC technologies are categorised as high temperature aqueous solutions (HT DAC) and caused dioxide in the 2016, with an annual growth rate of 2ppm (IEA, 2017). The Paris mentation of Negative CO 2 Emissions Technologies (NETs) (Kriegler et al., 2017; Rogelj et al., 2018). A range of options are available for CO 2 emissions removal. CO 2 emissions can be captured at point sources such as flue gases from conventionalpowerplantsor non-energeticsectorssuchas cement the transport sector, which account for 50% of global GHG emis- CO 2 capture to the undeniable are capable of is capturing CO 2 directly fromthe atmosphere.Hitherto, plants have been doing it naturally to some extent. Nonetheless, they cannot keep up with the increasing anthropogenic emissions (Goeppert et al., 2012). Afforestation, bioenergy with carbon capture and storage (BECCS) and enhanced weathering were introduced to reduce CO 2 con- centration in the atmosphere (Williamson, 2016). However, their commercial feasibility is limited, as all of these measures are associated with risks. Large-scale BECCS and afforestation threat biodiversity, water and food security, as both are characterised by * Corresponding author. Contents lists available Journal of Cleaner els Journal of Cleaner Production 224 (2019) 957e980 E-mail address: Mahdi.Fasihi@lut.fi (M. Fasihi). Agreement aims to mitigate climate change and keep temperature rise well below 2 C14 C and preferably 1.5 C14 C in comparison to the pre- industrial age by united efforts of all countries (UNFCCC, 2015). To achieve this goal, along with sharply cutting anthropogenic GHG emissions, actions are needed for active CO 2 removal by imple- sions, are just impossible to neutralise byconventional applications (Seipp et al., 2017). These facts lead necessity of finding additional solutions that capturing CO 2 independent of origin and location. Another approach for climate change mitigation 2 increased from 280ppm in the pre-industrial era to 403ppm in 2 and marine transport. Large amount of small emitters, such as in 1. Introduction The problem of global warming (GHG) emissions, mainly carbon dangerous levels. CO concentration https://doi.org/10.1016/j.jclepro.2019.03.086 0959-6526/© 2019 The Authors. Published by Elsevier penditures, energy demands and costs have been estimated under two scenarios for DAC capacities and financial learning rates in the period 2020 to 2050. DAC system costs could be lowered significantly with commercialisation in the 2020s followed by massive implementation in the 2040s and 2050s, making them cost competitive with point source carbon capture and an affordable climate change mitigation solution. It is concluded that LT DAC systems are favourable due to lower heat supply costs and the possibility of using waste heat from other systems. CO 2 capture costs of LT DAC systems powered by hybrid PV-Wind-battery systems for Moroccan conditions and based on a conservative scenario, without/ with utilisation of free waste heat are calculated at 222/133, 105/60, 69/40 and 54/32 V/t CO2 in 2020, 2030, 2040 and 2050, respectively. These new findings could enhance DAC s role in a successful climate change mitigation strategy. © 2019 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). by greenhouse gas (CO 2 ), has reached atmosphere has rapidly plants. However, some plants are too old and cannot be retrofitted. Moreover, even in plants with CO 2 removal systems, not all emis- sions are captured as the average capture rates are in the range of 50e94% (Leeson et al., 2017). On the other hand, it is not possible to directly capture CO emissions produced by long-distance aviation low temperature solid sorbent (LT DAC) systems, from an energy system perspective. DAC capital ex- Accepted 8 March 2019 Available online 14 March 2019 study, a literature review and techno-economic analyses of state-of-the-art DAC technologies are per- Techno-economic assessment of CO 2 dir Mahdi Fasihi * , Olga Efimova, Christian Breyer LUT University, Yliopistonkatu 34, 53850, Lappeenranta, Finland article info Article history: Received 14 October 2018 Received in revised form 25 January 2019 abstract CO 2 direct air capture (DA Despite technical advance long-term costs as well as journal homepage: www. Ltd. This is an open access article air capture plants has been increasingly discussed as a climate change mitigation option. the past decade, there are still misconceptions about DAC s current and , water and area demands. This could undermine DAC s anticipated role at ScienceDirect Production evier.com/locate/jclepro under the CC BY license (http://creativecommons.org/licenses/by/4.0/). er Pro huge land requirements (Smith et al., 2016). Enhanced weathering provokes rising pH values in rivers and changing the chemistry in oceans (Kohler et al., 2010). Besides afforestation/reforestation, BECCS and enhanced weathering, the full portfolio of NETs also includes biochar, ocean fertilisation and soil carbon sequestration (Fussetal.,2018;Minxetal.,2018),whichmayhavetobeappliedin aportfolioofNETsforeffectiveclimatechangemitigation(Buietal., 2018). CO 2 Direct Air Capture (DAC), besides BECCS, is the other option for capturing CO 2 from the atmosphere, diluted gases and distrib- utedsourcesofcarbonviaindustrialprocesses(Broehmetal.,2015; Goeppert et al., 2012; Lackner, 2009). DAC is a relatively new and innovative technology in early commercial stages (Nemet et al., 2018), which in a long term perspective, along with conventional technologies, can help humankind to control and mitigate climate change (Keith, 2009; Sanz-PC19erez et al., 2016). In this paper, a techno-economic assessment of the main CO 2 direct air capture technologies, from an energy system point of view, has been carried out. The remaining sections of the paper are as follows: Section 2 describes the methodology. In section 3,a literature review has been carried out. In section 4, available technologies have been described and the collected techno- Nomenclature BECCS Bioenergy with Carbon Capture and Storage capex Capital Expenditures CCS Carbon Capture and Storage CCU Carbon Capture and Utilisation COP Coefficient of Performance DAC Direct Air Capture DACCS Direct Air Carbon Capture and Storage FLh Full Load hours GHG Greenhouse Gas HT High Temperature LCOD Levelised Cost of CO 2 Direct Air Capture LT Low Temperature MOF Metal Organic Frameworks MSA Moisture Swing Adsorption NET Negative Emission Technology M. Fasihi et al. / Journal of Clean958 economic data is categorised and summarised in the form of ta- bles. The final model of main technologies in 2020 are introduced. Later, DAC capital expenditures, energy demands and costs have been estimated under two scenarios for DAC capacities and finan- cial learning rates in the period 2020 to 2050 and sensitivity ana- lysesforthemostvaluableparametersaredone.Further,DAC sarea and water demands, as well as CO 2 compression, transport and storage are presented. In section 5, relevanceof DACwith respect to the Paris Agreement, as well as benefits and challenges of the main DAC technologies are discussed. Later, more factors on the final costs of large-scale DAC systems are examined and results are compared to projections from companies or literature. Moreover, a cost comparison to point source carbon capture (PSCC), as one of the competing technologies is performed. In addition, the cost share of CO 2 DAC in power-to-gas systems has been investigated. Finally, conclusions are drawn in section 6. 2. Methodology and data An extensive review has been performed considering literature published from the early 2000s to the present time that are rele- vant to this research. Research was conducted in the following manner: data gathering via such platforms as ScienceDirect, Sco- pus, Google Scholar, ResearchGate, official websites of companies and international agencies such as Intergovernmental Panel on Climate Change (IPCC) and International Energy Agency (IEA). The following keywords were used: CO 2 capture plant, CO 2 capture methods, CO 2 scrubbing, CO 2 separation, direct air capture, cost of CO 2 capturing, carboncapturestart-upcompaniesandatmospheric CO 2 capture. A database of relevant data has been created from all the reviewed publications, for further analyses. Recalculation and aligning of the findings were conducted. All parameters are pre- sented on a comparable scale for classification of all available technologies and to deliver the final models, including long-term estimations. A sensitivity analysis of the most valuable variables is performed. Cost numbers from different years presented in USD are con- vertedtoeurosbyusing afixedexchange ratioof 1.33USD/V, as the long term average exchange rate. As an exception, cost numbers fromKeithetal.(2018)andvaluesinothercurrenciesareconverted to euros based on exchange rates of the corresponding year. equations (1)e(4) below have been used to calculate the lev- elised cost of electricity (LCOE), the levelised cost of heat (LCOH) opex Operating Expenditures PSCC Point Source Carbon Capture PtG Power-to-Gas PV Photovoltaic RE Renewable Energy SNG Synthetic Natural Gas TSA Temperature Swing Adsorption TVSA Temperature Vacuum Swing Adsorption WACC Weighted Average Cost of Capital Subscripts el electricity fix fixed p peak th thermal var variable duction 224 (2019) 957e980 and the levelised cost of CO 2 DAC (LCOD). Abbreviations: capital expenditures, capex, annuity factor, crf, annual operational expen- ditures, opex, fixed, fix, variable, var, annual CO 2 production of DAC plant, Output CO2 , full load hours per year, FLh, electricity demand of DAC plant per t CO2 produced, DAC el.input , heat demand of DAC plant per t CO2 produced, DAC heat.input , fuel costs, fuel,efficiency, h, coeffi- cient of performance of heat pumps, COP, weighted average cost of capital, WACC, lifetime, N. A WACC of 7% is used for all the calculations in this study. LCOE ¼ Capex,crf þOpex fix FLh þOpex var þ fuel h (1) LCOH ¼ Capex,crf þOpex fix FLh þOpex var þ fuel h þ LCOE COP (2) the first who proposed the same approach on an industrial scale. In M. Fasihi et al. / Journal of Cleaner Production 224 (2019) 957e980 959 addition, he has benchmarked the system with two previous studies on thermodynamic levels. Stolaroff et al. (2008) discussed optimisation of energy demand and possible reduction of final costs by improving the contactor part. The extensive report of American Physical Society (APS) by Socolow et al. (2011) compared post-combustion CO 2 capture methods to DAC systems based on the work of Baciocchi et al. (2006). Zeman (2014) investigated the APS report and proposed a reduction in final costs of avoided CO 2 by using low-carbon electricity and minimising plastic packing materials of the contactor part. Li et al. (2015) investigated the optimal operation of the system proposed in the early work of Zeman (2007) by using wind power and battery as the energy in- puts. All the above mentioned works applied different approaches to improve the performance of aqueous alkaline solution, in particular sodium hydroxide; whereas, Nikulshina et al. (2009) presented a single-cycle system carrying out continuous removal of CO 2 via serial CaO-carbonation at higher temperatures (of about 365e400 C14 C) and CaCO 3 -calcination at 800e876 C14 C, powered by concentrated solar power (CSP). Mahmoudkhani and Keith (2009) LCOD ¼ Capex DAC ,crf þOpex fix Output CO 2 þOpex var þDAC el:input ,LCOE þDAC th:input ,LCOH (3) crf ¼ WACC,ð1þWACCÞ N ð1þWACCÞ N C01 (4) Maturityleveloftechnologiesisalsotakenintoconsideration,as the focus of this research is on pilot and commercial-scale tech- nologies, while the theoretical and laboratory-scale studies have been included as well. Costandtechnicaltrendsbasedontechnologyevolutionover20 years of active research and development are identified. As a result, up to date data is used for the long-term estimation of key pa- rameters for the time periods 2020 to 2050 in 10-year steps, based on adapted learning rates. 3. Literature review The first application of capturing CO 2 from ambient air was introduced in the 1930s in cryogenic air separation plants and later it found its application in life support systems of manned closed systems such as space stations and submarines (House et al., 2011). The first systems dated back to 1965 were not regeneratable (Isobe et al., 2016). Whereas, modern space shuttles are all equipped with regeneratableCarbonDioxideRemovalAssembly(CDRA)thathelps to maintain habitable environment for crewmembers (NASA, 2006). Due to ultra dilute concentration of CO 2 in the atmosphere, chemical sorbents with strong binding characteristics became widely discussed in literature. An aqueous solution of strong bases is used in conventional PSCC technologies and many researchers have investigated its applicability to DAC. Keith et al. (2006) ana- lysed physical and economic limits of BECCS and aqueous solution- based DAC and concluded the second option to be feasible in the near term. However, high-grade (900 C14 C) heat demand of aqueous solution-based DAC could limit the options for heat source and increase the costs. Baciocchi et al. (2006) tried to optimise the system based on the same chemical solution and applied two different calcium carbonate precipitators. Zeman (2007) was one of suggested a novel approach to avoid calcium carbonate in the loop, by using Sodium Tri-Titanate. The technique requires 50% less high-grade heat than conventional causticisation and the maximum temperature required is reduced by at least 50K, from 900 C14 C to 850 C14 C. Holmes and Keith (2012) and Holmes et al. (2013) suggested potassium hydroxide (KOH) as a non-toxic solution and discussed the results of laboratory-scale and prototype tests of improved contactor parts. Keith et al. (2018) provided a detailed techno-economic analysis of a 1 Mt CO2 /a design based on a real pilot plant for the first time. Another major group of scientific publications are focused on systems based on adsorption process. Temperature swing adsorp- tion (TSA) is the main DAC method in this category, described by Kulkarni and Sholl (2012) and Sinha et al. (2017). Unlike typical aqueous solution-based systems, the regeneration in solid sorbent DAC happens at relatively lower temperatures (80e100 C14 C), which ischeapertoproduceorcouldbeavailableaswasteheatfromsome industrial plants, such as combined heat and power plants, power plants with cooling tower, pulp and paper mills, steel or glass making plants, or waste heat from exothermic synthetic fuels productio