Written by Saba Manzoor from Imperial College London, whose attendance at the UKCCSRC Cardiff Biannual Meeting was supported by the ECR Meeting Fund.
The first two presentations in the Biomass CCS session were given by Dr Maria Botero of cmcl innovations and Dr Karen Finney of the University of Leeds.
Techno-economics and global sensitivity analysis for biomass based CO2 capture storage and utilisation (CCSU) technologies – Dr Maria Botero, cmcl innovations
The talk highlighted the fact that to date there is little activity at industrial scale on the application of CO2 capture technologies to co-fired or dedicated biomass power plants. This dearth of practical data increases the complexity and uncertainties associated with the estimation and road mapping of biomass CCS technologies. The industry’s progression to the large fossil-based CCS demonstration projects is slow due to high cost and requirement of significant government subsidies. Recent setbacks and cancellations of the coal-based CCS projects will further delay the development of biomass CCS. This, however, also presents an opportunity for lower TRL biomass CCS technologies. Incentivising negative CO2 emissions via the capture and storage of biogenic CO2 under the EU emissions trading scheme is highly important.
The presentation focused on the results of the development and application of the Model Development Suite (MoDS) to biomass based CO2 capture storage and utilisation technologies. The first case study involved the techno-economic assessment of biomass based power generation combined with CO2 capture for storage (TESBiC project). Twenty eight bio-power CCS technology options involving combustion or gasification of biomass (either dedicated or co-fired with coal) together with pre-, oxy- or post-combustion CO2 capture are studied for LHV efficiencies, capital and operating costs (CAPEX and OPEX), and regulated emissions as a function of scale/capacity, co-firing, and the extent of CO2 capture; while covering the critical timescales up to 2050. It was suggested that biomass CCS is attractive for small (50MWe), intermediate (250MWe) and large (~ 600 MWe) scales. At large scales, the issue of ‘’sustainable biomass procurement’’ needs careful consideration. For the eight biomass-based power generation combined with carbon capture technologies varying over a wide range of TRLs, from TRL 3 to TRL 8, the range of techno-economic parameters are the following: ~5-15% : range of efficiency drop ; 45-130 % range of the increase CAPEX (£/MWe) with CO2 capture, ~ 4 -36% range of increase in OPEX (£/yr) with carbon capture. CAPEX, LCOE: generation scales and fuels costs are the main drivers.
In the second case study, MoDS was applied to perform global sensitivity analysis of a CO2 capture and utilisation (CCU) process that involves the production of algae-derived syngas using dual fluidized bed (DFB) gasifier (C-FAST project). A global sensitivity analysis was performed to determine the impact of key process parameters (i.e. gasification temperature, feed water content, steam of biomass ratio, and fuel-air equivalent ratio) on the product yield and cold gas efficiency. It was emphasized that the results presented could assist in benchmarking gasification against other algae conversion strategies in terms of process efficiency, feasibility and impact on the environment. The sensitivity of the production cost of algal-derived diesel was shown to decrease in the following order: algal oil content> algal specific annual productivity> plant capacity> Carbon price increase rate> PBR unit CAPEX. It was found that crude oil and carbon price increase rate influence long-term ROI substantially, as compared to the negligible impact on the short-term ROI. Plants solely producing algal biodiesel perhaps need supplementary revenue from producing additional value-added products.
The talk concluded by introducing the third case study which was in progress, the “Assessing CO2 utilisation technologies in the European Context (ACUTE)” project. The objectives were to develop and validate process flow models for CO2 utilisation options and to analyse current and future estimate for process, demand and corresponding elasticises for the CCU product.
BIO-CAP-UK: Air/Oxy Biomass Combustion with CO2 captures Technology- A UK study, Karen Finney, University of Leeds.
The presentation discussed the research agenda and funding for industrial secondments associated with the project which is a two year programme funded through UKCCSRC Call 1. It is a consortium of three university partners (Edinburgh, Leeds and Tyndall Manchester), which also brings together the UKCCSRC Research Centre and the Supergen Bioenergy Hub. The primary research aim that was highlighted by the speaker was to accelerate progress towards achieving operational excellence for flexible, efficient and environmentally sustainable Bio-CCS thermal power plants by developing and accessing fundamental knowledge, pilot plant tests, techno-economics and LCA.
The project comprised of four main work pages which are the following: (1) Fundamental studies and biomass characterisation biomass combustion rate - fundamental studies to be performed on fuel, char and ash characterisation. A range of fuels are to be tested but most detailed studies will be carried out on those intended for pilot-scale test such as white wood pellets, EI Cerrejon coal and a torrefied wood. Other fuels used for comparison include Pittsburgh coal, pine and white wood chips. Tests for fuel characterisation would also be performed which would include proximate and ultimate analyses, TGA combustion in air and CO2-O2, TGA pyrolysis in N2 and in CO2 and DTF char preparation test. Tests on char will also be carried out for proximate and ultimate analysis, TGA, SEM/EDX and BET SA. These would also be accompanied by tests on ash residues using XRF, XRD and AFT. The speaker also explained the data that would be provided by these analyses. (2) Pilot-scale plant campaign at UKCCSRC PACT - Technical assessment of up to 100% biomass firing using PACT facilities and investigation into dedicated biomass powder and co-firing with coal will be conducted. It is aimed to design a 250 kW combustion ring which can run in air-mode firing with amine-based post combustion carbon capture or oxy-fuel combustion with flue gas recirculation. There will also be a need to provide information for subsequent modelling on operational experience; flue gas recycle, optimal burner settings and combustion efficiency; ash formation and composition; heat flux/transfer; and emissions measurements. (3) Power plant simulations for air-/oxy-biomass combustion – process simulation linked to CFD modelling of the power plant and virtual power plant simulations. (4) Bio-CSS value chain in the UK – developing viable process configurations for different bio-CSS options.
The speaker concluding by saying that all the data from the four work packages will be fed into the life cycle and techno-economic assessments.