Prospective techno-economic and environmental assessment of carbon capture at a refinery and CO2 utilisation in polyol synthesis

Abstract

Keywords:Carbon capture and utilisation CO 2 economy CO 2 -based polyols CO 2 emissions reduction Pedigree analysis A B S T R A C T CO 2 utilisation is gaining interest as a potential element towards a sustainable economy. CO 2 can be used as feedstock in the synthesis of fuels, chemicals and polymers. This study presents a prospective assessment of carbon capture from a hydrogen unit at a refinery, where the CO 2 is either stored, or partly stored and partly utilised for polyols production. A methodology integrating technical, economic and environmental models with uncertainty analysis is used to assess the performance of carbon capture and storage or utilisation at the refinery.Results show that only 10% of the CO 2 captured from an industrial hydrogen unit can be utilised in a commercial-scale polyol plant. This option has limited potential for large scale CO 2 mitigation from industrial sources. However, CO 2 capture from a hydrogen unit and its utilisation for the synthesis of polyols provides an interesting alternative from an economic perspective. The costs of CO 2 -based polyol are estimated at 1200 €/t polyol, 16% lower than those of conventional polyol. Furthermore, the costs of storing the remaining CO 2 are offset by the benefits of cheaper polyol production. Therefore, the combination of CO 2 capture and partial utilisation provides an improved business case over capture and storage alone. The environmental assessment shows that the climate change potential of this CO 2 utilisation system is 23% lower compared to a reference case in which no CO 2 is captured at the refinery. Five other environmental impact categories included in this study present slightly better performance for the utilisation case than for the reference case.

Hydrogen production from natural gas and biomethane with carbon capture and storage – A techno-environmental analysis

“…Conversely, only few studies exist on the combined technical and environmental assessment of hydrogen production from natural gas or biomethane with CCS. The few results suggest that the life cycle Global Warming Potential (GWP) reduction of adding CCS to steam reforming plants varies from 35% to over 100%, 16,17 although the latter performance was only achieved by accounting for replacement of greenhouse gas (GHG) intensive grid electricity with low-carbon electricity produced by the fully abated steam reformer. 16 The existing studies more oen focus on techno-economics, 8,[17][18][19][20] and show that at a hydrogen cost increase of between 20-60 percent, roughly 55% to 90% of plant-wide CO 2 emissions can be captured.…”

Consequential life cycle assessment of carbon capture and utilization technologies within the chemical industry

“…28,60 CO 2 -based polyether polyol is formed similarly to the conventional synthesis; however, propylene oxide is partly substituted by CO 2 . 27 Marginal suppliers…”

“…5,6,[12][13][14][17][18][19] Other LCAs focused on the assessment of more complex molecules produced via CCU, like methyl propionate, 20 DME, 11,19,21 DMC, 17,22 OME, 23 (jet) fuels, 24,25 and polymers. 4,14,21,26,27 A recurrent conclusion from these studies is that emissions of greenhouse gases are reduced when producing the chemicals via CCU while using electricity from renewable resources compared to fossil-based production. However, in one study 22 this is not the case although best-case estimates were taken.…”

Analysis of CO2 utilization into synthesis gas based on solar thermochemical CH4-reforming

“…Besides, the techno-economic analysis indicated that the introduction of CCS required additional costs and thus higher electricity prices [2] . Thus, developing Carbon Capture and Utilization (CCU) technologies can overcome these issues by contributing to carbon sequestration into valuable products such as green fuel and chemical products [1,[5][6][7] . Utilizing CO 2 captured, for example, to produce syngas suitable for dimethyl carbonate (DMC) synthesis can reduce the GWP by 4.3 times and ozone layer depletion by 13 times compared to the conventional DMC process [4] .…”