Emission Value Correction

The equations are taken from Continuous Emission Monitoring by James A. Jahnke (April 3, 2000).

Correct wet-basis concentrations to dry-basis concentrations

\[c_d = \frac{c_w}{1-m_{Flue Gas}}\]

where

• \(c_d\) = dry-basis concentration value (ppm or percent)
• \(c_w\) = wet-basis concentration value (ppm or percent)
• \(m_{Flue Gas}\) = moisture fraction of the flue gas

To correct a concentration value for dilution, emissions can be expressed in three ways; with reference to a specified CO₂, O₂, or excess air value.

CO₂ correction (Corrected to 12% CO₂)

\[c_{d(12\% CO_2)} = c_w \times \frac{12}{\%CO_{2w}} =c_d \times \frac{12}{\%CO_{2d}}\]

The concentration can be determined using either a wet-basis or a dry-basis concentration value as long as the emissions and CO₂ are both measured on a wet basis or on a dry basis.

O₂(6% O₂)

\[c_{d(6\% O_2)} = c_d \times \frac{20.9 - 6.0}{20.9 - \%O_{2d}}\]

Excess Air Correction

Excess Air (EA) corrects to 50%.

\[c_{d(50\% EA)} = c_d \times \frac{100+\%EA}{150}\] \[\%EA = \frac{\%O_2 - 0.5\%CO}{0.266\%N_2 - \%O_2 + 0.5\%CO}\]

CO% is usually negligible, this calculation requires a dry O₂ measurement or a wet O₂ measurement