KINETICS OF HCL REACTIONS WITH CALCIUM AND SODIUM SORBENTS FOR IGCC FUEL GAS CLEANING

Experiments for HCl sorption by calcium and sodium sorbents have been carried out with simulated gases of compositions typical for ''air-blo wn'' and ''oxygen-blown'' IGCC fuel gases. The concentration of CO2 af fects the behaviour of HCl sorption by Ca-sorbents but does not influe nce the performance of Na-sorbents in the temperature range 300-600 de grees C. The sorbent panicle size has a slight effect on HCl sorption by Na2CO3 in the range 90-250 mu m. The optimum temperature for the re action was found to be between 400 and 500 degrees C. This has been at tributed to a combination of reaction kinetics and sintering. A mathem atical model has been developed to simulate gas solid reactions in fix ed beds. The coefficient of gas diffusion through the product layer (N aCl) was obtained at 300-600 degrees C.