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SAMPLE 3 Plant Operation Consulting Reports
Enclosed is a summary of analysis for the #1,2 and3 plant locations. This
report is as complete as possible with the data present and available and can be used as a
guide for better plant performance.
#1 Plant:
Exhaust Fan:
- 41,000 ACFM (Static pressure @ temperature unknown).
- 2-125 HP electric motor drive @ 1750 RPM @ 156 Full Load Amps operating at 55
and 42 motor amps.
- Fan operating temperatures are excessive.
Fugitive Dust System:
- Batcher dust line with damper appearing ineffective when opening and then
closing.
- Screen dust line with no valve or damper and open to atmosphere devaluing
exhaust fan effectiveness.
- Little or not air seals on batcher or screen devaluing exhaust fan
effectiveness.
Dryer:
- No drum air seals on front or rear of dryer resulting in excess air leakage
devaluing exhaust fans effect.
- Dryer exit gas temperature of 390 degrees F., resulting in higher than normal
exhaust fan temperatures of 320 degrees F. and inherently devaluing exhaust fan
effectiveness.
- Static suction pressure at Dryer exit was unreadable and may have been bordering
on zero pressure.
- Single flop style damper at exit of dryer at full open (not a very effective
place or type of damper).
- Additional fliting may improve heat transfer to aggregate and reduce exhaust fan
operating temps.
Burner:
- Genco model FP-103 with Scott 75 HP model S-960 blower @ 3555 RPM and operating
on 5.3 PSI of Natural Gas.
- Burner Blower flange leaks were repaired.
- Burner operating at 90-100% burner position.
Dry Knockout Scrubber:
- Appears to be used as a velocity expansion tank to allow heavier air borne
particulates to fall out prior to reaching the exhaust fan (not sure of its overall
effectiveness in the process).
Vertical Wet Scrubber:
- This unit is being operated at a dry cyclone very ineffectively as there is no
provision to remove the dust particles at the bottom subsequently they are carried out to
the Horizontal wet scrubber.
Horizontal Wet Scrubber:
- This unit is doing a very ineffective job of scrubbing or water collecting,
definite means for failing any
EPA testing procedure.
- It appears that the current configuration is promoting the condition commonly
referred to as stack raining.
- I have discussed with Plants Superintendent possible ways to remedy this
condition.
Conclusion:
Sealing up all possible air leaks will improve the performance of the exhaust
fan along with improving fliting in the hot gas zone to get more heat transfer and reduce
fan operating temperatures thus allowing the exhaust fan to move more air, steam and
products of combustion. Modifying the configuration of the horizontal wet scrubber will
significantly improve the stack raining and particulate scrubbing problems. The
installation of a performance air damper with auto/manual controls will allow the control
of excess air to fuel (the heating of unwanted air) thus improving fuel usage/ton of mix
produced. Having gas and pilot gas regulators tested and repaired if needed to assure
proper gas regulation to the burner and will also allow for pressure adjustability. Only
after improving these condition above should have the burned calibrated to the new
operating conditions. Calibration prior may result in very little overall increase of
performance.
Plant 2:
Venturi Damper:
- Venturi damper is in place but inoperable, has no auto/manual controls and no
damper drive motor.
Dryer:
- There is no front drum seal rear seal is in poor condition..
- Dryer fliting could be improved for better heat transfer, with the use of a wet
scrubber all possible heat transfer will increase plant performance (do not modify the
feed end of the of the dryer).
Burner:
- Genco AF-60- 60HP-3510 RPM-70 FLA.- Natural Gas @ 5.6 PSI.
- Experienced puffing at the burner end indicating a lack of oxygen and a near
zero static suction pressure.
Exhaust Fan:
- Inspection cover appears to be leaking excessive air possibly effecting fan
performance.
Primary Collectors:
- Flop gates inoperable (counter weights missing).
Conclusion:
The repair of any air leaks will always help performance, drum seals, flop
gates, inspection plates, screen and batcher seals. Install venturi damper motor and
auto/manual controls, this will allow the control of excess air not needed for combustion.
Improve dryer fliting in the hot gas zone (do not modify fliting in the feed end of
dryer). Keep in perspective or monitor the natural gas usage of the hot oil heater in
order to determine actual plant cubic ft./ton VS Hot oil heater.
Plant 3:
Burner:
- Genco model AF-40-40HP- 3550 RPM-Used oil @ 48 PSI @ ambient temperature.
- No used oil preheater in order for proper SSU rating of the burner oil (poor
atomization of fuel).
- Burner set at 100% of burner fuel to 50% of available burner air (possible over
firing).
- Combustion Test resulted in 13% CO2, 3.3% O2 and Excess of 2000 PPM at alarm CO.
(incomplete combustion). Oxygen is too low and Carbon Monoxide is too high.
Exhaust Fan:
- 125 HP - 1760 RPM-151 Amps Full Load- Actual operating amps @ 108-112-109.
- Operating @ 252 degrees F. @ 4.4 " of suction.
- Total static pressure of 9.7" @ 252 degrees F.
Damper:
- No damper at this plant
Dryer:
- Exit gas temperature of 318 degrees F. @ .6 inches of suction.
Conclusion:
The burner appears to be over-firing (rich in fuel) with a high concentration
of carbon monoxide and low concentration of oxygen. This may be partially a result of not
preheating the burner fuel in conjunction with miscalibration. Again reducing any and all
air leaks will add to improved performance. Improved dryer fliting in the hot gas zone can
help the performance of the exhaust fan by transferring more heat to the aggregate and
allowing the exhaust fan to move more air, steam and products of combustion. With the
possibility for more exhaust fan capacity comes the necessary control of excess air needed
for all operating conditions.
Call your burner manufacturer and ask them what the viscosity of your fuel
should be and then order a viscometer cup from them to determine how far off your
viscosity is.
Ken and Clarence
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