Exergetic, economic and carbon emission studies of bio-olefin production via indirect steam gasification process

Abstract

The indirect steam gasification of biomass to olefins (IDBTO) coupled with CO2 utilization was proposed and simulated. Energy and exergy efficiencies, net CO2 emissions, and economic evaluation were performed against IDBTO as well as the direct oxygen-steam gasification of biomass to olifins (DBTO).The influences of unreacted gas recycling fraction (RU) and CO2 to dry biomass mass ratio (CO2/B) on the thermodynamic performance of the processes were also studied. The results showed that the yields of olefins of DBTO and IDBTO were 17 wt% and 19 wt%, respectively, the overall energy and exergy efficiencies of the IDBTO were around 49% and 44%, which were 8% and 7% higher than those of the DBTO process, respectively. A higher RU was found favor higher energy and exergy efficiencies for both routes. Besides, for the IDBTO process, it is found that the addition of CO2 to gasification system led to an improvement in both energy efficiency and exergy efficiency by around 1.6%. Moreover, lifecycle net CO2 emission was predicted to be -4.4 kg CO2 eq./ kg olefins for IDBTO, while for DBTO, it was -8.7 kg CO2 eq./ kg. However, the quantitative economic performance of IDBTO was superior to that of the DBTO process.

Analytical Review of Life‐Cycle Environmental Impacts of Carbon Capture and Utilization Technologies

“…This option, which allows producing chemicals such as olefins, DME and methanol, can be considered environmentally sustainable and is generally preferred over other treatments (e. g., incineration) to deal with solid waste [136] . Similar approaches were recommended by Jiang et al., [129] who used biomass as the starting raw material, and Peters et al., [137] who proposed using manure and municipal solid waste as feedstock for CO 2 in Power‐to‐Gas projects. The use of liquid manure for this purpose would result in not only a reduction of CO 2 emissions (the authors report a net value of −85.6 per MJ of generated fuel), but also reducing acidification and eutrophication of soil and water by avoiding land spreading this material.…”

“…Methanol to olefins is a widely studied alternative that has started to be applied at large scale. The first commercial methanol‐to‐olefins plant was launched in 2010 in China, with a production rate of 600 kt y −1 [129] …”

“…Jiang et al [129] . assessed the gasification of biomass and use of CO 2 to produce olefins by two methods to generate syngas: using steam and oxygen for the gasification process in a reactor combined with a catalytic reforming unit (direct method) and using steam in a gasifier connected with a combustor (indirect method).…”

Kinetic and thermodynamic investigations of CO2 gasification of coal chars prepared via conventional and microwave pyrolysis

“…To evaluate the syngas composition and cold gas efficiency, thermodynamic modelling of char gasification using CO 2 was carried out using Aspen Plus (Li et al 2014). Detailed simulation descriptions can be found in our previous work (Jiang et al 2019(Jiang et al , 2020. The CGE represents conversion of the char energy content to the lower heating value of syngas, as defined by Eqs.…”

An economic analysis of twenty light olefin production pathways

“…While TEA of ethylene production via bioethanol dehydration with different sources revealed that not all scenarios enable the cost-competitive production of ethylene at current market prices [15 , 21] . Jiang et al [22] proposed bioolefin production via MTO coupled with the CO 2 utilization process and studied the exergetic, economic and carbon emission profiles. These design concepts or suggestions are positive to promote the development of certain renewable pathways.…”