Technical feasibility and sensitivity analysis of medical waste gasification by the converter gas

The temperature of the converter gas at the outlet of the converter is as high as 1600 °C, and the output is about 120–150 Nm3/tons steel. In order to improve the utilization efficiency of heat energy, and the recovery rate and calorific value of the converter gas, medical waste (MW) gasification of by the converter gas was proposed. At the same time, the technical feasibility and sensitivity analysis of MW gasification were conducted by Aspen Plus soft on the basis of Gibbs free energy minimization. The simulated results were successfully validated with the experimental data from MW gasification in a bench scale gasifier. Moreover, the influence of the gasification temperature, steam/MW ratio and MW/converter gas ratio on the composition, the low heating value (LHV), gas yield (GY), and carbon conversion efficiency (CCE) were evaluated. During the simulation, the mixed gas (CO: CO2: N2 = 40: 20: 40) was used as the simulated converter. The simulated results demonstrated that the optimum parameters were 1050 °C gasification temperature, 0.8 steam/MW ratio, and 0.08 kg/m3 MW/converter gas ratio, CO, H2, and CO2 reached to 46.54%, 38.09%, and 0.10% due to Boudouard reaction and water-gas shift reaction. After MW gasification, CO2 content in the converter gas was decreased from 20% to 0.10%, and LHV was increased from 5480 to 10,021 kJ/Nm3. •No additional heat was need for MW gasification by the converter gas.•1050 °C, 0.8 steam/WM ratio, and 0.08 kg/m3 MW/converter gas were the optimum parameters.•CO2 content of the converter gas was decreased from 20% to 0.10% by MW gasification.•LHV was increased from 5480 to 10,125 kJ/Nm3 by MW gasification.