Parametric techno-economic studies of coal/biomass co-gasification for IGCC plants with carbon capture using various coal ranks, fuel-feeding schemes, and syngas cooling methods

Abstract

Summary Because of biomass's limited supply (as well as other issues involving its feeding and transportation), pure biomass plants tend to be small, which results in high production and capital costs (per unit power output) compared with much larger coal plants. Thus, it is more economically attractive to co‐gasify biomass with coal. Biomass can also make an existing plant carbon‐neutral or even carbon‐negative if enough carbon dioxide is captured and sequestered (CCS). As a part of a series of studies examining the thermal and economic impact of different design implementations for an integrated gasification combined cycle (IGCC) plant fed with blended coal and biomass, this paper focuses on investigating various parameters, including radiant cooling versus syngas quenching, dry‐fed versus slurry‐fed gasification (particularly in relation to sour‐shift and sweet‐shift carbon capture systems), oxygen‐blown versus air‐blown gasifiers, low‐rank coals versus high‐rank coals, and options for using syngas or alternative fuels in the duct burner for the heat recovery steam generator (HRSG) to achieve the desired steam turbine inlet temperature. Using the commercial software, Thermoflow®, the case studies were performed on a simulated 250‐MW coal IGCC plant located near New Orleans, Louisiana, and the coal was co‐fed with biomass using ratios ranging from 10% to 30% by weight. Using 2011 dollars as a basis for economic analysis, the results show that syngas coolers are more efficient than quench systems (by 5.5 percentage points), but are also more expensive (by $500/kW and 0.6 cents/kW h). For the feeding system, dry‐fed is more efficient than slurry‐fed (by 2.2–2.5 points) and less expensive (by $200/kW and 0.5 cents/kW h). Sour‐shift CCS is both more efficient (by 3 percentage points) and cheaper (by $600/kW or 1.5 cents/kW h) than sweet‐shift CCS. Higher‐ranked coals are more efficient than lower‐ranked coals (2.8 points without biomass, or 1.5 points with biomass) and have lower capital cost (by $600/kW without using biomass, or $400/kW with biomass). Finally, plants with biomass and low‐rank coal feedstock are both more efficient and have lower costs than those with pure coal: just 10% biomass seems to increase the efficiency by 0.7 points and reduce costs by $400/kW and 0.3 cents/kW h. However, for high‐rank coals, this trend is different: the efficiency decreases by 0.7 points, and the cost of electricity increases by 0.1 cents/kW h, but capital costs still decrease by about $160/kW. Copyright © 2016 John Wiley & Sons, Ltd.

Numerical Investigation of Coal and Biomass Co-Gasification Regimes in Entrained-Flow Oxygen-Steam Blown Reactor

“…зом, чтобы газификация биомассы была технически и экономически оправданной. Как показывают теоретические и экспериментальные работы, при совместной газификации угля и биомассы часто существует оптимальное соотношение, при котором реализуется достаточно эффективная конверсия компонентов топливной смеси при незначительном изменении технической эффективности [11]. Настоящая работа посвящена исследованию термических режимов конверсии топливных частиц в реакционной зоне поточных газогенераторов.…”

Parametric Study on Co-Feeding of Municipal Solid Waste and Coal in an IGCC Power Plant with Pre-Combustion Carbon Capture

“…Pre-combustion CO 2 percentage is high in IGCC, leading to a more energy-efficient carbon capture and storage (CCS) scheme downstream. Captured CO 2 can be sequestered underground in geological caverns, used in enhanced oil recovery schemes, or can be subjected to ex-situ or in-situ mineral carbonization to achieve a neutral or a negative carbon powerplant depending on feedstock composition [4,5,6]. For this reason, co-feeding coal with MSW or biomass is preferable [6].…”

“…Captured CO 2 can be sequestered underground in geological caverns, used in enhanced oil recovery schemes, or can be subjected to ex-situ or in-situ mineral carbonization to achieve a neutral or a negative carbon powerplant depending on feedstock composition [4,5,6]. For this reason, co-feeding coal with MSW or biomass is preferable [6]. MSW contains food wastes, organic debris like papers, plastics, rubbers, lignocellulosic materials and typically has an LHV of 7 MJ/kg [7].…”

Combustion and heat transfer characteristics of co-firing biomass and coal under oxy-fuel condition

“…Recently, there are a number of investigations on biomass utilization which are beneficial to control the global warming . A refined model was proposed by Bunchmayr et al to conduct the CFD study on air staging combustion in a lab‐scale biomass furnace.…”

“…Recently, there are a number of investigations on biomass utilization which are beneficial to control the global warming. 21,22 A refined model was proposed by Bunchmayr et al 23 to conduct the CFD study on air staging combustion in a lab-scale biomass furnace. A computationally inexpensive steady flamelet model was used to calculate the gas phase combustion of wood chips.…”