2-01　Development of HCl Removal Process for Poly-Generation System with CO₂ Capture

Abstract

To develop a low-cost hydrogen chloride (HCl) removal process from syngas, removal characteristics of HCl using commercially available calcium hydroxide sorbent (CHS) were evaluated. The CHS was set into a quartz reactor of lab-scale fixed-bed test apparatus, and the simulated coal and waste plastic gasification gas containing 400-2000ppm HCl was fed into the reactor for a certain period. The results of gas analysis using a Fourier transform infrared (FT-IR) spectrophotometer showed that the CHS was able to reduce HCl to less than a few ppm. Elemental analysis and XRD analysis of the tested CHS revealed that the Ca in CHS reacted with HCl to produce CaClOH, and reacted with CO₂ to produce CaCO₃. In the temperature range of 250～450°C, CHS reacted better with HCl at lower temperatures. A low-cost two-stage halide removal system could be constructed by providing a small-scale high-performance sorbent such as sodium aluminate reactor as a backup process downstream of the CHS reactor.