Autothermal CaO looping biomass gasification

  • Shuming Zhang

Student thesis: Doctoral ThesisDoctor of Philosophy


Biomass gasification is considered a promising renewable energy technology to address climate change caused by greenhouse gas emissions and produce portable and clean energy products. However, biomass gasification has several challenges including poor syngas quality, low process energy efficiency and ash sintering. Autothermal CaO looping biomass gasification is directly maintained by the thermal compensation of carbonation reaction, which can maximize the production of combustible gas and reuse carbon dioxide in the flue gas. Firstly, the experiments were conducted in a lab-scale two-stage fixed bed reactor, and the results indicated that similar H2 yield could be obtained via autothermal CaO looping biomass gasification technology at lower operating temperatures. Sequentially, the inhibition of the sintering of simulated ashes (silica, potassium oxide and alumina) was investigated. Thirdly, the promotion of biomass gasification using thermal compensation generated in situ by CaO-CO2 in a fixed bed reactor was studied with emphasis. In addition, the effect of steam on the regeneration of CaO was also determined during biomass gasification from an energy-saving perspective. Lastly, a comparison between the autothermal CaO looping biomass gasification and sorption enhanced gasification were carried out based on the Aspen plus simulation and economic analysis with parameters including natural gas consumption, annual CO production, process energy efficiency, the total annual cost and the CO cost.

Thesis embargoed until 31 July 2023
Date of AwardJul 2022
Original languageEnglish
Awarding Institution
  • Queen's University Belfast
SupervisorChunfei Wu (Supervisor) & Beatrice Smyth (Supervisor)


  • Biomass gasification
  • CaO carbonation
  • syngas production

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