Improving Air Quality in Your Community
Outdoor Air - Industry, Business, and Home: Oil and Natural Gas Production

Additional Information
You can help oil and natural gas production facility owners and operators reduce emissions of hazardous air pollutants (HAPs) and volatile organic compounds (VOC) that may affect employees and the community by encouraging facilities to conduct these activities:
- Optimize glycol dehydration system
- Modify processes
- Maintain good housekeeping and equipment maintenance
- Practice recycling
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Optimize Glycol Dehydration System
How?- In a glycol dehydration system, glycol is regenerated in the reboiler and circulated back to the absorption tower, where it contacts the natural gas and removes water as well as hazardous air pollutants.
- Reduce the glycol circulation rate to 2 to 3 gallons of glycol per pound of water removed.
- Optimize flash tank temperature and pressure.
- Operate and maintain glycol at proper temperatures.
- One source estimates that approximately $390 to $39,400 per year are saved due to reductions in fuel usage [Glycol circulation reduction] (EPA).
- One source estimates savings to be as much as approximately $80,000 per year [Glycol circulation reduction] (Railroad Commission of Texas [RRC]).
- Reduces emissions because low recirculation rates decrease the amount of HAPs [Glycol circulation reduction].
- Lowers reboiler fuel consumption [Glycol circulation reduction].
- Removes lighter VOC and enhances condenser efficiency [Optimization of flash tank temperature and pressure].
- Fuel savings from using recovered emissions as fuel [Optimization of flash tank temperature and pressure].
- Avoidance of hydrocarbon contamination [Glycol operation and maintenance (O&M) at proper temperatures].
- Cost savings from decreasing glycol consumption [Glycol O&M at proper temperatures].
- Costs of reducing gas loss can is negligible [Glycol circulation reduction] (EPA).
- Natural Gas STAR Partners Lessons Learned (Production Sector): Optimize Glycol Circulation and Install Flash Tank Separators (PDF) (16 pp, 235 KB).
- Railroad Commission of Texas (RRC)
(Waste Minimization and Processing Operations).
- New Mexico Pollution Prevention/Best Management Practices Guide (full guide) (self-extracting ZIP file, 1.1 MB).
- New Mexico Pollution Prevention/Best Practices Pocket Guide for the New Mexico Oil and Gas Industry (PDF) (61 pp, 137 KB).
Modify Processes
How?- Replace triethylene glycol with diethylene glycol or ethylene glycol.
- Use glycol additives.
- Install flash tanks.
- Replace gas-assisted glycol pumps with electric pumps.
- Route dehydrator still emissions to a reboiler, firebox, first-stage compression, or flare.
- Eliminate the use of sparge or stripping gas in dehydrators.
- Replace glycol dehydrator with dessicant dehydrators.
- Reduces emissions by up to 50% by using diethylene glycol (DEG) and up to 90% by using ethylene glycol (EG) [Replacement of triethylene glycol (TEG) with DEG or EG].
- Reduces emissions by approximately 70% to 85% [Use glycol additives].
- One source estimated that approximately $2,100 to $21,300 per year is saved in reducing gas losses [Installation of flash tanks] (EPA).
- Savings of approximately $1,080 to $108,000 in gas (depending on TEG rate and inlet gas temperature and pressure) for switching from gas-assisted to electric glycol pumps [Replacement of gas-assisted glycol pumps with electric pumps] (EPA).
- Replacing glycol dehydrators with desiccant dehydrators reduces gas usage costs by approximately $3,200 and operation and maintenance costs (O&M) by approximately $1,200 [Replacement of glycol dehydrators with desiccant dehydrators] (EPA).
- Reduces emissions from the reboiler by capturing methane and toxics entrained in the TEG [Installation of flash tanks].
- Improved condenser efficiency [Installation of flash tanks].
- Reduces operating costs due to recovering gas from the flash tank to use as fuel [Installation of flash tanks].
- Reduces production costs by using recovered gas in an upstream compressor [Installation of flash tanks].
- Recovered gas can be used as a stripping gas in the reboiler [Installation of flash tanks].
- Increases condenser efficiency by decreasing the amount of noncondensable gas going to the condenser [Elimination of use of sparge or stripping gases in dehydrators].
- Increases system efficiency [Replacement of gas-assisted glycol pumps with electric pumps].
- Reduces emissions, gas looses, operation, and maintenance costs [Replacement of gas-assisted glycol pumps with electric pumps].
- Reduces energy costs [Replacement of gas-assisted glycol pumps with electric pumps].
- Reduces fuel requirements [Rerouting of emissions].
- One source estimates that depending on site-specific factors, flash tank installation costs range from $1,200 to $2,200 [Installation of flash tanks].
- Depending on pump size, capital costs for switching from gas-assisted to electric glycol pumps range from $1,000 to $10,000 [Replacement of gas-assisted glycol pumps with electric pumps] (EPA).
- Annual labor costs for maintaining electric pumps: $200 [Replacement of gas-assisted glycol pumps with electric pumps] (EPA).
- Replacing glycol dehydrators with desiccant dehydrators yields capital costs of $12,750 [Replacement of glycol dehydrators with desiccant dehydrators] (EPA).
- Natural Gas STAR Partners Lessons Learned (Production Sector): Optimize Glycol Circulation and Install Flash Tank Separators (PDF) (16 pp, 235 KB).
- Natural Gas STAR Partners Lessons Learned (Production Sector): Replacing Gas-assisted Glycol Pumps with Electric Pumps (PDF) (17 pp, 274 KB).
- Natural Gas STAR Partners Lessons Learned (Production Sector): Replacing Glycol Dehydrators with Desiccant Dehydrators (PDF) (21 pp, 784 KB).
- Railroad Commission of Texas
(Waste Minimization and Processing Operations).
- New Mexico Pollution Prevention/Best Practices Pocket Guide for the New Mexico Oil and Gas Industry (PDF) (61 pp, 137 KB).
- Paper from the Society of Petroleum Engineers entitled "Benefits of Using Deliquesing Desiccants for Gas Dehydration." (PDF) (6 pp, 280 KB).
- Abstract from "Reduction of Glycol Loss from Gas Dehydration Unit at Offshore Platform in Bombay Offshore - A Case Study."
Maintain Good Housekeeping and Equipment Maintenance
How?- Test glycol regularly to avoid potential problems (e.g., corrosion).
- Reduces emissions.
- Costs associated with more frequent testing.
- New Mexico Pollution Prevention/Best Practices Pocket Guide for the New Mexico Oil and Gas Industry (PDF) (61 pp, 137 KB).
Practice Recycling
How?- Use vented or flared gas as fuel.
- Collect vented or flared gas, compress, and sell as product.
- Reduces emissions by eliminating a source of emissions.
- Adds revenue from the sale of recovered vapors.
- Maintenance costs as low as $250/unit for a vapor recovery system.
- New Mexico Pollution Prevention/Best Management Practices Guide (full guide) (self-extracting ZIP file, 1.1 MB).