Open AccessDEVELOPMENT OF A CALCIUM-BASED SORBENT FOR HOT GAS CLEANUP
Author(s) -
T.D. Wheelock,
L. K. Doraiswamy
Publication year - 1999
Language(s) - English
Resource type - Reports
DOI - 10.2172/780840
Subject(s) - sorbent , aluminate , calcium looping , cement , cement kiln , materials science , calcium carbonate , pellets , pelletizing , calcium oxide , coating , carbonation , adsorption , mineralogy , metallurgy , composite material , chemistry , organic chemistry
The preparation and testing of potential sorbents for removing H{sub 2}S and COS from hot coal gas continued. Two preparation methods received the most consideration. Both methods involve pelletizing powders in a revolving drum under moist conditions followed either by heat treatment or steam curing to harden the pellets, depending on the particle bonding mechanism. One method was used to pelletize mixtures of calcium carbonate and either alumina or a calcium aluminate cement in a single step. Another method was used to pelletize powdered limestone in an initial step followed by the application of a coating consisting of both limestone and a hydraulic cement in a second step. By employing this method, an especially promising material was produced consisting of a limestone core surrounded by a shell consisting initially of 80 wt.% limestone and 20% wt.% calcium aluminate cement. The best material exhibited both an acceptable crushing strength and adsorption capacity for H{sub 2}S