ESPs are used in petroleum refineries to control particulate emissions from fluid-catalytic
cracking units and boilers. In a refinery, heavy crude is broken down into lighter components
by various distilling, cracking, and reforming processes. One common process is to "crack"
the high-molecular-weight, high-boiling-point compounds (heavy fuel oils) into smaller, lowmolecular-
weight, low-boiling-point compounds (gasoline). This is usually done in a fluidcatalytic
cracking (FCC) unit.
In an FCC unit, the feed stream (heavy gas oils) is heated and then mixed with a hot catalyst
that causes the gas oils to vaporize and crack into smaller hydrocarbon-chain compounds.
During this process, the catalyst becomes coated with coke. The coke deposits are eventually
removed from the catalyst by a catalyst-regeneration step.
In the regenerator, a controlled amount of air is added to burn the coke deposits off the catalyst
without destroying it. The gases in the regenerator pass through cyclones to separate large catalyst
particles. The gases can sometimes go to a waste heat boiler to burn any carbon monoxide
and organic emissions present in the gas stream. The boiler's exhaust gas still has a high
concentration of fine catalyst particles. This flue gas is usually sent to an electrostatic precipitator
to remove the very fine catalyst particles.
ESPs can also reduce particulate emissions from boiler exhausts. Oil-fired and, occasionally,
coal-fired boilers generate steam that is used in many processes in the refinery. The flue gas
from boilers is frequently sent to ESPs to remove particulate matter before the gas is exhausted
into the atmosphere. ESPs designed similarly to those used on industrial and utility boilers are
used on FCC units and petroleum refinery boilers.
cracking units and boilers. In a refinery, heavy crude is broken down into lighter components
by various distilling, cracking, and reforming processes. One common process is to "crack"
the high-molecular-weight, high-boiling-point compounds (heavy fuel oils) into smaller, lowmolecular-
weight, low-boiling-point compounds (gasoline). This is usually done in a fluidcatalytic
cracking (FCC) unit.
In an FCC unit, the feed stream (heavy gas oils) is heated and then mixed with a hot catalyst
that causes the gas oils to vaporize and crack into smaller hydrocarbon-chain compounds.
During this process, the catalyst becomes coated with coke. The coke deposits are eventually
removed from the catalyst by a catalyst-regeneration step.
In the regenerator, a controlled amount of air is added to burn the coke deposits off the catalyst
without destroying it. The gases in the regenerator pass through cyclones to separate large catalyst
particles. The gases can sometimes go to a waste heat boiler to burn any carbon monoxide
and organic emissions present in the gas stream. The boiler's exhaust gas still has a high
concentration of fine catalyst particles. This flue gas is usually sent to an electrostatic precipitator
to remove the very fine catalyst particles.
ESPs can also reduce particulate emissions from boiler exhausts. Oil-fired and, occasionally,
coal-fired boilers generate steam that is used in many processes in the refinery. The flue gas
from boilers is frequently sent to ESPs to remove particulate matter before the gas is exhausted
into the atmosphere. ESPs designed similarly to those used on industrial and utility boilers are
used on FCC units and petroleum refinery boilers.
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