Measuring Fugitive Emissions of Hydrocarbons at

Gas Processing Plants

Allan Chambers, P.Eng.Alberta Research Council Inc.

www.arc.ab.ca

15th Annual Emission Inventory Conference

http://www.arc.ab.ca/

Objectives of this projectObjectives of this project

demonstrate new optical methods to: measure fugitive emissions of hydrocarbons locate leaks

apply methods to reduce fugitive emissions compare measured emissions with estimated

emissions

Optical MethodsOptical Methods

Differential Absorption Light Detection and Ranging (DIAL) laser-based, remote measurement of gas

concentration quantify hydrocarbons in emission plume

Gas leak imaging camera modified infra-red video camera video identification of hydrocarbon leaks

DIAL Measurement of FugitivesDIAL Measurement of Fugitives

Spectrasyne Ltd.

DIAL (DIAL (www.spectrasyne.ltd.ukwww.spectrasyne.ltd.uk))

SOSO22 Plume from StackPlume from Stack

DIAL

plume cross section300 m downwind

stack height

Validation of SpectrasyneValidation of Spectrasynes DIALs DIAL

in Europe: six validation studies with CH4 or C2+ DIAL mass emissions within -3 to -12%

in Alberta:

Source Stack Monitor(kg/h)

DIAL(kg/h)

delta(%)

SO2 from incinerator 340 304

67.1

-11

NO from gas turbine 66.5 +1

Allocating Fugitive EmissionsAllocating Fugitive Emissions

Compressors

ProcessBuilding

Distance from DIAL

C2+ Emissions from a Gas Plant

Emissions at Sweet Gas PlantEmissions at Sweet Gas PlantEm

issi

on

(kg/

h)

0

10

20

30

40

50

60

70

Process PlantCompressors

LPG StorageWellsite/Battery

CondensateTanks

C2+CH4

DIAL Surveys at Alberta Gas PlantsDIAL Surveys at Alberta Gas PlantsPlant CH4 Emissions

(kg/hr)C2+ Emissions

(kg/hr)Benzene(kg/hr)

A - 38 -

-

C (2003) 146 342 -

C (2004) 100 58 0.24

E 144 41 0.06

-

B 104 (450) 42

D 124 86

- process flares account for 10 to 15% of CH4 emission- 100 kg/hr equals $270,000/yr at $6/GJ

DIAL Method SummaryDIAL Method Summary

directly measure fugitive emissions of: CH4 C2+ hydrocarbons (VOCs) benzene SO2, NOx, mercaptans

locate areas of plant with highest emissions locate and quantify large leaks measure fugitives from total site

Gas Leak Imaging CamerasGas Leak Imaging Cameras

- Hawk camera by Leak Surveys Inc., Texas- visual indication of hydrocarbon leak, no quantification

2005 FLIR model

Leak Reduction at a Sour Gas PlantLeak Reduction at a Sour Gas Plant

DIAL survey in 2003 leak camera survey found 33 leaks and most

repaired

DIAL survey in 2004 leak camera survey found 7 leaks

Reduced Emissions at Gas PlantReduced Emissions at Gas Plant

CH4 emissions reduced by 50%

C2+ emissions reduced by 93%

> $800,000/year at $6/GJ

0

50

100

150

200

250

300

350

emis

sion

s (kg

/h)

CH4 C2+

20032004

Comparison with EstimatesComparison with Estimates

estimation methods used when reporting fugitive emissions to regulators

Canadian Association of Petroleum Producers recommends methods based on API Emission Factor procedures

Measured vs. EstimatesMeasured vs. Estimates

Estimated DIAL MeasuredPlant Methane (tonnes/y)

Sweet Gas Plant E 188 1264 Sour Gas Plant C 251 1020

VOCs (tonnes/y) Sweet Gas Plant E 14.9 129 Sour Gas Plant C 94.4 545

Benzene (tonnes/y) Sweet Gas Plant E 0.45 0.52 Sour Gas Plant C 0.39 2.10

Measured vs. Estimates Measured vs. Estimates VOCsVOCs at a Sweet Gas Plantat a Sweet Gas Plant

Item Estimated Emissions DIAL Measurement

(tonnes/y) (tonnes/y) tanks 4.91 11.0 flare 0.72 8.5 combustion sources

4.93 -

plant fugitives 2.69 107.1 other 1.63 2.6 Total 14.8 129

Refinery VOC Emissions (preliminary)Refinery VOC Emissions (preliminary)

Estimated Emissions (tonnes/y)

DIAL C2+Measurements1

(tonnes/y)stack or point release 98.69 N/A

storage or handling 153.0 5,090

fugitive releases 407.1 4,880

spills 11.5 N/A

Total 670.4 9,970

1. measured hourly emissions x 8,064 hours

DIAL Measured CDIAL Measured C2+2+ (VOC) (VOC) -- RefineryRefineryArea C2+ (kg/h) % of total

coker + vacuum unit 211 17.1new process area 68.3 5.5old process area north 105 8.5old process area south 56.8 4.6

new tanks 137 11.1

cooling towers 164 13.3feed tanks 141 11.4intermediate tanks 68.7 5.6product tanks 277 22.4

bullets and spheres 7.4 0.6Site total 1237

Emissions, European RefineriesEmissions, European Refineries

0.00%

0.10%

0.20%

0.30%

0.40%

0.50%

0.60%

0.70%

0.80%

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25Refinery

Rest of refinery

Process plant

All of refinery

HC

Em

issi

ons (

% o

f thr

ough

put)

0.17% of throughput for AB refinery

Spectrasyne Ltd.

Project ConclusionsProject Conclusions

DIAL can quantify fugitive emissions gas visualization cameras can improve leak

detection DIAL gas processing plant measurements

were 4 to 8 times CAPP detailed estimates storage tanks and flares were larger sources

than indicated by estimation methods potential to recover significant $s of

fugitive hydrocarbon emissions

AcknowledgementsAcknowledgements funded by:

Canadian Association of Petroleum Producers (CAPP)

Environment Canada British Columbia Oil and Gas Commission Alberta Environment

overseen by: Air Issues Committee, Petroleum Technology

Alliance Canada (PTAC) final reports available at www.ptac.org

Objectives of this projectOptical MethodsDIAL Measurement of FugitivesDIAL (www.spectrasyne.ltd.uk)SO2 Plume from StackValidation of Spectrasynes DIALAllocating Fugitive EmissionsEmissions at Sweet Gas PlantDIAL Surveys at Alberta Gas PlantsDIAL Method SummaryGas Leak Imaging CamerasLeak Reduction at a Sour Gas PlantReduced Emissions at Gas PlantComparison with EstimatesMeasured vs. EstimatesMeasured vs. Estimates VOCs at a Sweet Gas PlantRefinery VOC Emissions (preliminary)DIAL Measured C2+ (VOC) - RefineryEmissions, European RefineriesProject ConclusionsAcknowledgements