BEHAVIOR OF MERCURY IN HAZARDOUS-WASTE TREATMENT BY REVERSE-BURN GASIFICATION

The fate of mercury in the treatment of hazardous waste by reverse-burn gasification was investigated. Mercuric chloride was loaded into coal char at a rate of 333 mug/g and the char was subjected to reverse-burn gasification to determine if mercury would be vaporized in the process as it is in typical incineration processes. Two types of mercury vapor traps, Amberlite IR-124 (a sulfur-containing cation-exchange resin) and triple-reverse-burned coal char (TRB Char), were examined for their ability to remove mercury vapor from the gasification reactor exhaust gas. Detection of mercury vapor exiting the gasification reactor or mercury traps was accomplished by collection on a gold surface in a specially designed mercury vapor collection tube. Mercury was measured by flameless atomic absorption following thermal desorption from the collection tube. Although mercury was vaporized in the gasification process, TRB Char proved to be an effective sorbent for the removal of mercury vapor from the exhaust gas.