Challenge

Coal ash is a waste product of coal combustion used for electrical power generation.  Fly ash (from smoke stacks) and bottom ash (from boilers and combustion chambers) may contain trace metals including Aluminum, Arsenic, Cadmium, Chrome, Copper, Mercury, Nickel, Lead, Selenium, Vanadium and Zinc.  This ash is removed from the boiler using a water slurry and stored in holding basins or ash piles within the power generation facility.

Solution

The client provided a one-gallon sample for analysis and column studies were performed to select the proper ion exchange resin for the Vanadium removal.  These studies showed that anion ASC resin effectively removed the Vanadium below the required discharge levels.  Siemens Water Technologies, formerly USFilter, provided prefiltration, pumps and floating suction for the project, as well as installation services.  Three vessels, each with 30 cubic feet of ASC resin were installed and Vanadium levels were monitored for compliance with local discharge standards. 

Exhausted resin from these vessels is transported to Siemens' RCRA-permitted facility in Roseville, Minnesota for regeneration and metal recovery.  All residuals from the regeneration process are sent for metals recovery and no waste is destined for a landfill.  The regenerated resin can be reused in future applications.

Result

Siemens' solution provided a quick response with minimal capital investment for the client, as well as providing a local service and environmentally conscious disposal.  This economical solution also takes away the concern for future liability issues for the client and environmental concerns for those living near the facility.

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