Performance analysis of municipal solid waste gasification with steam in a Plasma Gasification Melting reactor

Plasma Gasification Melting (PGM) is a novel gasification technology which offers a promising treatment of low-heating-value fuels like municipal solid waste (MSW), medical waste (MW) and other types of waste. By considering the differences in pyrolysis characteristics between cellulosic fractions and plastics in MSW, a semi-empirical model was developed to predict the performance of the PGM process. The measured results of MSW air and steam gasification in a PGM demo-reactor are demonstrated and compared with the model predicted results. Then, the effects of dimensionless operation parameters (ER, PER, and SAMR) are discussed. It was found that all three numbers have positive effects on system cold gas efficiency (CGE). The reasons can be attributed to promoted tar cracking by enhanced heat supply. The effects of PER and ASME on syngas LHV are also positive. The influence of ER on syngas pyrolysis can be divided into two parts. When 0.04 < ER < 0.065, the effect of ER is on LHV positive; when 0.065 < ER < 0.08, the effect of ER is positive. This phenomenon was explained by two contradictory effects of ER. It is also found that interactions exist between operation parameters. For example, increasing PER narrows the possible range of ER while increasing SAMR broadens possible ER range. Detail extents for those operation parameters are demonstrated and discussed in this paper. Finally, the optimal point aiming at obtaining maximum syngas LHV and system CGE are given.

► A process simulation model was used to simulate the PGM.
► Heat supply from both plasma and internal combustion is beneficial for PGM due to favored tar cracking.
► Steam injection has positive effects on syngas yield and LHV.
► The optimal syngas LHV can be obtained at PER = 0.14, SAMR = 0.8 and ER = 0.055.