System analysis for synthesis gas (syngas) production in Pakistan from municipal solid waste gasification using a circulating fluidized bed gasifier

A synthetic natural gas (syngas) production study via municipal solid waste (MSW) gasification system in a circulating fluidized bed gasifier is presented with the aim to produce clean energy. The syngas production offers a substantial energy alternative especially in regions such as Pakistan where the rates of MSW production are high and resources are less. MSW gasification could be an effective process that will not only contribute to solve solid waste problem but also reduces waste disposal landfills. The capacity of the plant was set based on the availability of feed and selexol process which was integrated with a carbon capture process. The energy conversion performance for the overall integrated process was evaluated based on material and energy balances and the system performance. The plant produced 30 MW of energy from a 50 MW estimated plant capacity. About 84% of syngas is produced from the overall process after capturing the carbon dioxide (CO2) using Selexol process. A process model was developed using ASPEN PLUS simulator to calculate the performance of the circulating fluidized bed (CFB) gasifier. Effect of gasification temperature, equivalence ratio, and moisture content was analyzed. Higher moisture content results in degradation of syngas quality. Large amount of MSW needs greater heat input and this increases the process cost. Gasifier temperatures were found to have a stronger impact on the syngas composition. The simulation results and energy balances in combination impart useful information in a search of proficient and clean utilization of MSW energy.