System designs can be either up flow or down flow
where polluted air enters the inlet plenum of the precipitator. Turning
vanes and perforated plate evenly distribute the gas flow.
The gas then enters the round collection tubes,
which are bundled, between two tube sheets in a honeycomb design for down
flow operation. Above the collection tubes are two sets of spray headers.
The first spray header continually mists the collection tubes with small
water droplets, which are immediately charged and flow down the tube,
in the direction of the gas flow. This continually wets the tubes to prevent
sticky particulates from adhering to the tubes. The second spray header
is the flushing header, which periodically sprays a larger amount of water
to flush the collected precipitate out of the collection tubes into the
lower plenum.
In the middle of each collection tube is a rigid
pin corona-generating electrode. Each electrode suspends from an alignment
rack, which is supported by insulators located out of the gas stream.
A 65-80 KV transformer rectifier energizes the electrode rack with an
automatic controller.
As the dust and aerosol particles enter the collection
tubes they become charged from a bombardment of negatively charged electrons.
The negatively charged particles adhere to the wetted collection tube
and are periodically flushed into the lower plenum.
The lower plenum is designed to demist the gas
stream and drain all the collected precipitate to the customers collection
system.