addressing uncertainty in oil and natural gas industry greenhouse

Uncertainty for Regenerator CO 2 Emissions – Coke Burn Rate Approach
(Compendium Equation 5-4)
Applying API Compendium Equation 5-4, the estimated CO 2 emissions from the regenerator would be:
tonnes Coke Burned 0.93 tonnes C 44 tonnes CO2
E
CO
= 119,750 × × 408,348 tonnes CO
2
2
/year
year tonnes Coke 12 tonnes C =
The uncertainty is calculated by applying Equation 4-6 and using the relative uncertainty values.
U( rel) = U( rel) + U( rel)
U rel
CO2
2 2
Coke burned
C content
2 2
( )
CO
= 15 + 5.5 = 15.98%
2
Uncertainty for Regenerator CO 2 Emissions – “K 1 , K 2 , K 3 ” Approach
(API Compendium Equation 5-5)
Applying the air rate to API Compendium Equation 5-5, the CO 2 emission estimate is:
⎡0.2982 kg - min 2,150 dscm ⎤ 44 tonne 8760 hr
E
CO
= × × ( 11% + 9% ) × × × 411,862 tonnes CO
2 ⎢
=
2
/yr
⎣ hr - dscm % min ⎥
⎦ 12 1,000 kg yr
Note, the K 1 term (0.2982 kg-min/hr-dscm%) is a constant.
For this calculation, the uncertainty associated with the sum of the CO 2 and CO is determined first. This
uncertainty is calculated by applying Equation 4-4, using the absolute uncertainties.
U ( abs)
U ( abs)
U ( abs)
concentrations
CO2
CO
=
=
0.5
0.5
=
2
2
U ( abs)
+ (0.05×
11)
+ (0.05×
9)
2
Reproducibility
2
2
= 0.743
= 0.673
+ U ( abs)
2
Variability
U ( rel)
U ( rel)
CO
CO2
0.743
= 100% × = 6.76%
2
11
0.673
= 100% × = 7.47%
9
Equation 4-4, using the absolute uncertainties, is also applied to combine these compositions.
U ( abs)
=
U ( abs)
2
concentrations
CO2
+ U ( abs)
2
CO
U ( abs)
U ( rel)
concentrations
concentrations
=
0.743
2
+ 0.673
= 1.002
1.002
= 100% × = 5.01%
11+
9
2
The CO 2 uncertainty is then calculated by applying Equation 4-6 and using the relative uncertainty values.
Pilot Version, September 2009 5-11