Wet ESP Removes Sub-micron Lead Fumes
A Midwestern manufacturer heat treats metal materials in a furnace that generates low concentrations of lead fumes. The fumes are sub-micron in size, making them difficult to remove. The facility is compliant with their existing permit, but wants to be pro-active to control emissions further. They investigated several technologies including HEPA and cartridge filters, Venturi scrubbers, and wet electrostatic precipitators (WESPs). Because of the small particle size, low concentration, and high removal efficiency, they had difficulty finding technologies or vendors willing to guarantee the requested performance limit.
The process conditions are similar to a secondary lead smelter WESP in Southern California. The lead smelter uses an Envitech WESP system to remove low concentrations of lead and other heavy metals from stack emissions. Based on actual lead smelter performance data, the customer selected an Envitech WESP.
The WESP system is an upflow design with gas flowing from bottom to top.
FlowWorks™ modeling of the conditioning section ensures uniform gas distribution across the collection tubes for maximum performance.
The collection section uses Envitech’s proprietary high performing electrode design which achieves high field strength and migration velocities for maximum removal efficiency.
The process consumes water through evaporation to cool and saturate the gas. A water treatment system is provided to reduce waste water storage and disposal.
The design submittal is complete and approved. Delivery and start-up are on track to occur in March 2012 with test results available in May. The design parameters are summarized below.