Amended Silicate Sorbents for Removal of Heavy Metals from Flue Gases

The Department of Defense uses specialized incinerators for the disposal of outdated munitions and agents. These units are subject to ever more stringent emissions regulations, especially with respect to lead, cadmium, and mercury. ADA Technologies withfunding from the EPA and U.S. DOE, has developed a new family of specialized sorbents that have been shown to be effective in the capture of mercury from coal-fired flue gas streams. Because of their chemical structure, these materials will be quiteefficient in the removal of lead and cadmium as well. The sorbents use a commercial-commodity natural mineral substrate, making them low-cost to prepare and use. These materials work as a chemisorbent, binding the target metals more securely than thephysisorption of activated carbon. In a Phase I SBIR project, ADA will quantify the ability of several formulations of sorbent from this new family to remove the target metals from a simulated incinerator gas stream, and prepare a conceptual design for afull-scale system to provide metals control in a military incinerator. In Phase II, a prototype system will be built and demonstrated on an operating unit. In addition to the removal of volatile metals from munition/agent incinerators, these sorbents canbe used in thermal treatment units being built to process DOE wastes. They will also be effective in treating exhaust gas from commercial hazardous waste incinerators. ADA has an agreement with CH2M Hill, an environmental engineering company, tocommercialize these sorbents for multiple applications.