Preparation for an EPA stack test is crucial in the process of passing that test. While most of this seems common sense, it’s easy to overlook something and discover too late that you’re on the road to failing your test. Certain parameters are essential to your success in that testing. These two documents are what I developed over the years to ensure successful test results.
Pre-Stack Test Field Data
Baghouse
Date__________________ Time____________________
General Conditions: Clear___ Cloudy___ Rain___
Elevation______________ FT Ambient Temp___________
Plant Model_______________
Cleaning: Remove rust, dirt, dust and scale in or on all internal surfaces.
Black light test with Visualite is mandatory prior to testing.
Air Ducts-House Inlet______________________ Condition___________________________
House Walls and Hopper___________________ Condition___________________________
Clean Air Plenum__________________________ Condition___________________________
Fan Housing and Wheel____________________ Condition___________________________
Exhaust Stack______________________________ Condition___________________________
Bag condition______________________________ # bags replaced______________________
Adjustments:
Baghouse pressure drop________ (3” to 5” recommended)
Fuel Type____________________
Fuel Pressure_________________ (adjust to minimum recommended by burner manufacturer)
Bag Cleaning Rate_____________ Seconds between pulses/rotor time.
Air Damper Control___________ (Manual position recommended)
Air Analysis: Bacharach Combustion Analyzer or equivalent is recommended.
CO_______ PPM. Too little air gives off carbon monoxide. ( 200 PPM or less)
O2_______ Too much air waste fuel, unburned air gives off oxygen. Normal range is 6-10%
CO2______ Maximum operating range of Carbon Dioxide is under 6-18 percent.
Checks:
Compressed Air Pressure_______________ (100 PSI recommended)
All Solenoids Operating________________ All Diaphragm Valves operating_________
No Compressed air leaks_______________ Pressure drop manometer tubing_________
Tests performed by____________________________
Pre-Stack Test Field Data
Wet Scrubber
Date__________________ Time____________________
General Conditions: Clear___ Cloudy___ Rain___
Elevation______________ FT Ambient Temp___________
Plant Model_______________
Cleaning: Remove rust, dirt, mud, and scale from all internal surfaces.
Air Ducts-Scrubber Inlet______________________ Condition______________________
Scrubber Walls______________________________ Condition______________________
Scrubber Tube-Inside________________________ Condition______________________
Sludge Trough-Full Length___________________ Condition______________________
Fan Housing and Wheel_____________________ Condition______________________
Exhaust Stack______________________________ Condition______________________
Any problem above MUST be remedied prior to stack test.
Adjustments:
Venturi Pressure Drop______________ (Minimum 13” to 14” recommended
Fuel Type_________________________
Fuel Pressure______________________ P.S.I. (Adjust as low as practical to maintain flame)
Venturi Nozzles____________________ P.S.I. (consult plant manual for pressure)
Air Damper Control_________________ (Manual position recommended)
Air Analysis: Bacharach Combustion Analyzer or equivalent is recommended.
CO_______ PPM. Too little air gives off carbon monoxide. ( 200 PPM or less)
O2_______ Too much air waste fuel, unburned air gives off oxygen. Normal range is 6-10%
CO2______ Maximum operating range of Carbon Dioxide is under 6-18 percent.
Ponds: An ample supply of clean natural water is vital for passing an EPA Compliance Test
Number of ponds being used_____ Pond size in gallons of water___________________
Date Pond Cleaned___________ Is a setting agent being used_____ Type_____________
Tests performed by____________________________
Once all of this data has been gathered you can easily determine if you will pass or fail the upcoming tests.
It’s important to remember that your stack test is the most important process that you are doing on that day. The results of that test dictates HOW you are permitted to operate for the rest of the permitted period. I strongly recommend that the focus be on passing the stack test and not on the paving operations.
In recent years I have seen a number of plants fail a stack test because the plant operator ignored good plant operational practices in an attempt to satisfy the demands of a paving superintendant who simply did not understand the importance of this one day of compliance testing.
