Reduction of energy consumption and enhancement of hydrogen yield from E-waste via plasma gasification process with waste heat recovery system

Electronic waste (e-waste) poses environmental issues and risks to health, but it holds polycarbonate, epoxy, and metal oxide, which have the potential for hydrogen production via the gasification process. This research involves the proper recycling of e-waste to an effective feedstock for hydrogen production via a plasma gasification process featuring a waste heat recovery system. During the plasma gasification process, the operating temperature is varied from 1500 to 3000 °C with an interval of 500 °C without a catalyst. The optimum plasma gasification temperature involves different concentrations of calcium oxide (CaO) catalyst for enriching the hydrogen yield. Effects of plasma gasification processing with a waste heat recovery system on energy consumption reduction, syngas yield, reactor stability, and carbon conversion efficiency are studied. The system featuring higher plasma gasification temperature (3000 °C) found reduced energy consumption (48.9%) and enhanced hydrogen yield of 66.7 mol/kg while reducing CH₄ and CO₂ emissions to 9.8 mol/kg and 10.5 mol/kg, respectively. The incorporation of a heat recovery system improved energy utilization efficiency to 71.5% and increased CCE (carbon conversion efficiency) from 69.8% to 91.6%. Additionally, CaO catalyst addition (15 wt%) further optimized gasification performance, leading to a hydrogen yield of 72.6 mol/kg while reducing CH₄ and CO₂ emissions to 8.1 mol/kg and 7.8 mol/kg, respectively. These findings highlight plasma gasification as a viable and sustainable technology for hydrogen production from e-waste, offering significant environmental and energy efficiency benefits.