Process Simulation of Co-Gasification of Raw Municipal Solid Waste and Bituminous Coal in CO₂/O₂ Atmosphere

• Main Authors: Guangchao Ding, Boshu He
• Format: Article
• Language: English
• Published: MDPI AG 2020-03-01
• Series: Applied Sciences
• Subjects: municipal solid waste (msw); bituminous coal; co-gasification technology; co₂/o₂ atmosphere; thermodynamic equilibrium model
• Online Access: https://www.mdpi.com/2076-3417/10/6/1921

An integrated CO₂/O₂ co-gasification system of municipal solid waste (MSW) and bituminous coal (BC) with CO₂ capture was developed and simulated by the Aspen plus, which mainly consisted of three processes: air separation unit, co-gasification system, and CO₂ absorption unit. In addition, raw syngas composition, cold gas efficiency (CGE), and overall energy efficiency (OEE) of the entail system were evaluated in detail with respect to the main operating parameters (gasification temperature, <i>T</i>; oxygen equivalence ratio, <i>R</i>_o; mole of CO₂ to carbon ratio, <i>R</i>_c; and the MSW blending ratio, <i>R</i>_M). The results indicated that the addition of BC improved the gasification of MSW. Higher gasification temperature increased CGE and OEE. Increasing the <i>R</i>_c ratio led to the decrease of H₂ mole fraction due to the enhanced reverse water-gas shift reaction. In addition, the CGE and OEE of the system decreased with increasing <i>R</i>_M. From the analyses of the parameters, the most optimal operating conditions were set as <i>T</i> = 900 &#176;C, <i>R</i>_o = 0.2, <i>R</i>_c = 0.5, and <i>R</i>_M = 0.6, and the corresponding OEE of the system reached 0.57. The system can achieve a large processing capacity of MSW at the cost of the efficiency loss of this condition.