Depending on the electrostatic precipitator chosen, production, installation and operation startup
may take from a few months to one or two years. In any case, proper installation procedures
will save time and money, and will also help in future operation and maintenance
(O&M) of the ESP.
Good coordination between the ESP designer (vendor) and the installation and maintenance
crews will help keep the ESP running smoothly for years. Occasionally this coordination is
overlooked. Because they are so large, ESPs are usually installed by skilled craftsmen who do
not work for the ESP vendor, and, therefore, may not be informed of specific installation
instructions. Since all design tolerances are critical (especially those affecting discharge and
collection electrode alignment), it is imperative that information about the proper installation
procedures be transferred from designers to installers.
Some key considerations during installation are:
• Easy access to all potential maintenance areas—fans, motors, hoppers, discharge devices,
dampers, flue gas flow rate and temperature monitors, insulators, rappers, T-R sets, and
discharge and collection electrodes
• Easy access to all inspection and test areas—stack testing ports and continuous emission
monitors (opacity monitors)
• Weather conditions—the ESP must be able to withstand inclement weather such as rain or
snow
During installation, the customer purchasing the ESP should be responsible for checking the
criteria presented below. The regulatory agency review engineer also should review the process
on which the ESP will be installed and verify that these items are being addressed.
1. Uniform flue gas distribution across the entire unit. Ductwork, turning vanes, baffle
plates, and inlets with perforated diffuser plates all affect flue gas distribution. These items
are usually installed in the field and should be checked visually. If improperly installed,
they induce high airflow regions that decrease collection efficiency and cause reentrainment
of collected dust, especially during rapping cycles.
2. Complete seal of ESP system from dust pickup to stack outlet. Air inleakage or outleakage
at flanges or collector access points either adds additional airflow to be processed or forces
the process gases to bypass the collector. Inleakage to a high-temperature system (hot-side
ESP) is extremely damaging, as it creates cold spots which can lead to moisture or acid
condensation and possible corrosion. If severe, it can cause the entire process gas temperature
to fall below the gas dew point, causing moisture or acid to condense on the hopper
walls, the discharge electrode, or collection plates. In addition, air in leakage and moisture
condensation can cause caking of fly ash in the hopper, making normal dust removal by
the discharge device very difficult. The best way to check for leaks is an inspection of the
walls from inside the system during daylight. Light penetration from outside helps to isolate
the problem areas.
3. Proper installation of discharge electrodes and collection plates. Collection electrodes are
usually installed first, and the discharge wires or rigid frames are positioned relative to
them. Check each section of electrodes to ensure that the electrodes are plumb, level, and
properly aligned.
4. Proper installation of rappers. Collection-plate rappers and discharge-electrode rappers
should be installed and aligned according to vendor specifications. Check magneticimpulse
rappers to see if they strike the support frame on the collection plates. Check hammer
and anvil rappers to see if the hammers strike the anvils squarely. Check vibrator rappers
installed on discharge wires to make sure they operate when activated. Rapper
frequency and intensity can be adjusted later when the unit is brought on-line.
5. Proper insulation.Most ESPs use some type of insulation to keep the flue gas temperature
high. This prevents any moisture or acids present in the flue gas from condensing on the
hoppers, electrodes, or duct surfaces. Because most ESPs are installed in the field, check
that all surfaces and areas of potential heat loss are adequately covered.
6. Proper installation and operation of discharge devices. It is important to check the operation
of the discharge devices before bringing the ESP on-line to see if they are properly
installed. Make sure that the discharge devices are moving in the right direction so they
can remove the dust freely from the hopper. A backward-moving screw conveyor can pack
dust so tightly that it can bend the screw.
Overfilled hoppers are common operating problems that can be avoided by proper installation
and maintenance of discharge devices. Installed as maintenance tools, dust-level
detectors in the hoppers can help alert ESP operators that hoppers are nearly full.
7. Smoothly running fans. Check fans for proper rotation, drive component alignments, and
vibration. Fans should be securely mounted to a component of sufficient mass to eliminate
excessive vibration.
In addition to the above items, each ESP installation should have its own checklist reflecting
the unique construction features of that unit. The installation crew should prepare a
checklist before beginning final inspection and initial startup. A prestartup checklist for
the initial startup suggested by Peter Bibbo (1982) is shown in Table
may take from a few months to one or two years. In any case, proper installation procedures
will save time and money, and will also help in future operation and maintenance
(O&M) of the ESP.
Good coordination between the ESP designer (vendor) and the installation and maintenance
crews will help keep the ESP running smoothly for years. Occasionally this coordination is
overlooked. Because they are so large, ESPs are usually installed by skilled craftsmen who do
not work for the ESP vendor, and, therefore, may not be informed of specific installation
instructions. Since all design tolerances are critical (especially those affecting discharge and
collection electrode alignment), it is imperative that information about the proper installation
procedures be transferred from designers to installers.
Some key considerations during installation are:
• Easy access to all potential maintenance areas—fans, motors, hoppers, discharge devices,
dampers, flue gas flow rate and temperature monitors, insulators, rappers, T-R sets, and
discharge and collection electrodes
• Easy access to all inspection and test areas—stack testing ports and continuous emission
monitors (opacity monitors)
• Weather conditions—the ESP must be able to withstand inclement weather such as rain or
snow
During installation, the customer purchasing the ESP should be responsible for checking the
criteria presented below. The regulatory agency review engineer also should review the process
on which the ESP will be installed and verify that these items are being addressed.
1. Uniform flue gas distribution across the entire unit. Ductwork, turning vanes, baffle
plates, and inlets with perforated diffuser plates all affect flue gas distribution. These items
are usually installed in the field and should be checked visually. If improperly installed,
they induce high airflow regions that decrease collection efficiency and cause reentrainment
of collected dust, especially during rapping cycles.
2. Complete seal of ESP system from dust pickup to stack outlet. Air inleakage or outleakage
at flanges or collector access points either adds additional airflow to be processed or forces
the process gases to bypass the collector. Inleakage to a high-temperature system (hot-side
ESP) is extremely damaging, as it creates cold spots which can lead to moisture or acid
condensation and possible corrosion. If severe, it can cause the entire process gas temperature
to fall below the gas dew point, causing moisture or acid to condense on the hopper
walls, the discharge electrode, or collection plates. In addition, air in leakage and moisture
condensation can cause caking of fly ash in the hopper, making normal dust removal by
the discharge device very difficult. The best way to check for leaks is an inspection of the
walls from inside the system during daylight. Light penetration from outside helps to isolate
the problem areas.
3. Proper installation of discharge electrodes and collection plates. Collection electrodes are
usually installed first, and the discharge wires or rigid frames are positioned relative to
them. Check each section of electrodes to ensure that the electrodes are plumb, level, and
properly aligned.
4. Proper installation of rappers. Collection-plate rappers and discharge-electrode rappers
should be installed and aligned according to vendor specifications. Check magneticimpulse
rappers to see if they strike the support frame on the collection plates. Check hammer
and anvil rappers to see if the hammers strike the anvils squarely. Check vibrator rappers
installed on discharge wires to make sure they operate when activated. Rapper
frequency and intensity can be adjusted later when the unit is brought on-line.
5. Proper insulation.Most ESPs use some type of insulation to keep the flue gas temperature
high. This prevents any moisture or acids present in the flue gas from condensing on the
hoppers, electrodes, or duct surfaces. Because most ESPs are installed in the field, check
that all surfaces and areas of potential heat loss are adequately covered.
6. Proper installation and operation of discharge devices. It is important to check the operation
of the discharge devices before bringing the ESP on-line to see if they are properly
installed. Make sure that the discharge devices are moving in the right direction so they
can remove the dust freely from the hopper. A backward-moving screw conveyor can pack
dust so tightly that it can bend the screw.
Overfilled hoppers are common operating problems that can be avoided by proper installation
and maintenance of discharge devices. Installed as maintenance tools, dust-level
detectors in the hoppers can help alert ESP operators that hoppers are nearly full.
7. Smoothly running fans. Check fans for proper rotation, drive component alignments, and
vibration. Fans should be securely mounted to a component of sufficient mass to eliminate
excessive vibration.
In addition to the above items, each ESP installation should have its own checklist reflecting
the unique construction features of that unit. The installation crew should prepare a
checklist before beginning final inspection and initial startup. A prestartup checklist for
the initial startup suggested by Peter Bibbo (1982) is shown in Table
Prestartup checklist for electrostatic
precipitators
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