Calculating Moly Converter Efficiencies | Teledyne API Model T201 NH3 Analyzer Operator Manual |
3.The first gas check is to test to see how much the converter is eating NO gas or out gassing NO gas. Bypass the converter in the machine, by placing a short piece of tubing in place of the converter. Perform a straight dilution with NO gas and air as a diluent gas. Input this 450 PPB NO gas into the analyzer, allow the machine to stabilize, and write down the NOx value on your data sheet on line 3.
4.Remove the converter bypass and install the converter back into the NOx sample stream, such that the NO sample goes through the converter again and allow the machine to stabilize. Write down your NOx value on your data sheet on line 4 AND line 6 of the data sheet.
5.Note the NO value and input that on line 9 of the data sheet.
6.Subtract line 3 from line 4 and write that number down on line 5. The spec on the data sheet is the value that we use here in house, and your spec might be a bit higher. We have found that on NEW Moly converters this spec is a good one that predicts a good performing Moly converter, but in an older converter might eat a bit more NO, and this would be acceptable. If it is a constant value, or changes little over time, this is not a problem the machine will calibrate this out.
7.The next step is to perform your GPT. Generate the same 450 PPB NO gas and input 400 PPB of O3 (or generate 450 PPB NO and 400 PPB NO2, if that’s what your calibrator says). Allow the machine to stabilize for 10 minutes and then write down the NOx value on line 7 and the NO value on line 10.
8.Subtract line 7 from line 6 and put that onto line 8
9.Subtract line 10 from line 9 and put that onto line 11
10.Put the number from line 8 into the letter A on line 12 and put the number from line 11 into the letter B on line 12.
11.Divide A by B and multiply it by 100 and put it into letter C on line 12.
12.Put the number in letter C onto the C on line 13 and subtract that value from 100 and put it into letter D on line 13. this is the converter efficiency.
13.This value should be >96%. If below 96%, replace the converter.
36 | 07271B DCN6646 |
