Filter System Resolves Asphalt Storage-tank Emissions

CECO Filters, Inc.ing distributor/manufacturer of asphalt products used large, heated tanks to store asphalt as a liquid for distribution to either tank trucks or directly to their manufacturing process. With heating of the asphalt to ensure drainage, the tanks came under a slight pressure, requiring venting of the asphalt vapors. The air-pollution regulatory agency for the area notified the company that the asphalt emissions were not in compliance with their environmental codes and ordered that the venting stop.

The company explored several methods of removing these fumes, including incineration systems. The distance between tanks, however, made combining the vented fumes from each tank to a common duct's leading to an incinerator impractical. An alternative, that each tank have its own incinerator, was too expensive.

Solution

The distributor/manufacturer contacted The <%=company%>. The company's engineers developed a fiber-bed filter system that would remove the asphalt fumes from the tank vent, collect the asphalt for return to the tank, and exhaust clean air to the atmosphere.

The filter bed filter is housed within a cylindrical carbon steel shell with inlet and exhaust fittings. A sump at the bottom of the shell permits draining the collected asphalt. The collection system operates without use of moving equipment.

Results

The distributor/manufacturer tested a unit on a single tank. The system operated as designed and met pollution-control codes. Its cost versus an individual incinerator unit represented a capital savings of more than 90 percent, with virtually no operating costs. Moreover, the system's filter-replacement costs very nearly equal the costs of fuel for an incineration system. The distributor/manufacturer consequently will install the filters in their plants throughout the U.S.

For additional information about this application or others employing Ceco's filter technology--including odor, opacity and mist-control uses--contact: <%=company%>, 1029 Conshohocken Road, Conshohocken, PA 19428. Tel: 800.220.8021; Fax: 610.825.3108.