EPA white papers offer hint of methane, VOC emissions

The US natural gas industry received a preview of a new regulatory push on Apr. 15 when the Environmental Protection Agency published white papers on emissions of methane and volatile organic compounds (VOCs) in five operational categories.

The agency released the papers for external peer review as part of a White House strategy to reduce methane emissions (OGJ Online, Mar. 29, 2014).

The white papers cover emissions from compressors, completions and production of hydraulically fractured oil wells, leaks, liquids unloading, and pneumatic devices.

EPA will accept public comments on its emissions estimates and technical assessments until June 16. Methane is a greenhouse gas (GHG), and VOCs are precursors to ground-level ozone.

Here are summary comments the white papers:

Compressors. Net methane emissions in 2012 in EPA’s current inventory of GHG emissions were 86,259 tonnes from production, 724,295 tonnes from gas processing, and 1.261 million tonnes from transmission and storage. Possible controls for reciprocating compressor emissions include period replacement of rod-packing systems. New technologies in use with compressors capture emissions and route them back to the process. For centrifugal compressors, emissions may be controlled by dry-seal designs. Dry-seal centrifugal compressors have lower emissions, require less maintenance, and are more energy-efficient than wet-seal units, and costs are comparable, EPA said. With wet-seal compressors, it might be feasible to capture emissions from seal oil and reroute recovered gas back to the compressor or another process or to burn the gas.

Completions and production from hydraulically fractured oil wells. Information is limited on uncontrolled emissions from fraced oil-well recompletions and controlled emission factors for fraced oil-well completions and recompletions. Estimates of uncontrolled methane emissions from hydraulically fractured oil-well completions range from 44,306 tons/year to 247,000 tons/year. Reduced-emission completions (RECs) can be effective in some oil wells producing associated gas. National data aren’t available for numbers of RECs or for shares of wells for which emissions were vented or flared during completion. Other technologies under investigation for controlling emissions during completion include gas reinjection, NGL recovery, and use of gas for power generation for local use.  

Leaks. EPA’s inventory estimates annual potential methane emissions from leaks at 332,662 tonnes from gas production, 33,681 tonnes from gas processing, and 114,348 tonnes from transmission. Studies indicate most methane and VOC leaks occur from a minority of components, and one indicated the leaks come from a minority of sites. Portable analyzers can effectively locate and measure leaks from production sites. The use of optical gas imaging and ambient/mobile monitoring is increasing and can be used in tandem. EPA’s studies indicate the cost of leak detection is “generally far larger” than that of leak repair. Directed inspection and maintenance programs can decrease leak emissions.

Liquids unloading. Liquids unloading of gas wells, according to EPA’s GHG inventory, accounted for 14% of all emissions from gas production. Most emissions from this source come from “a small percentage of wells.” Among several technologies the industry has developed to remove liquids from wells and lower emissions during blowdowns, the use of plunger lifts is the most common. Efficiency of plunger lifts in emission reduction varies greatly depending on how the system is operated.

Pneumatic devices. According to the EPA inventory, pneumatic-controller emissions are 13% of overall methane emissions from the oil and gas industry. Emissions from natural gas-driven pneumatic controllers vary depending on the industry sector—production, transmission, or storage—and the controller type. Low-bleed, gas-driven controllers can replace high-bleed, gas-driven controllers in many but not all applications. Where electric power is available, instrument air systems can replace natural gas-driven pneumatic controllers and eliminate methane and VOC emissions. Zero-bleed, mechanical, and solar-powered controllers can replace continuous-bleed controllers in some applications but aren’t broadly applicable. Techniques for mitigating emissions from pneumatic pumps, which result in venting, include use of instrument air pumps and electric pumps. EPA’s inventory estimates pneumatic pumps account for 16% of overall methane emissions from gas production and processing.

Related Articles

Congressional Republicans renew bid to halt sue-and-settle maneuvers

02/05/2015 Calling it an affront to regulatory accountability that results in unchecked compliance burdens, US Sen. Charles E. Grassley (R-Iowa) and US Rep. D...

Oil-price collapse may aggravate producing nations’ other problems

02/05/2015 The recent global crude-oil price plunge could be aggravating underlying problems in Mexico, Colombia, and other Western Hemisphere producing natio...

Goodlatte reintroduces bills to repeal, reform RFS

02/05/2015 Calling it “a true ‘kitchen table’ issue,” US Rep. Bob Goodlatte (R-Va.) reintroduced a pair of bills to address problems in the federal Renewable ...

MARKET WATCH: NYMEX oil drops, ending 4-day rally

02/05/2015 Crude oil prices dropped on the New York market Feb. 4 to settle below $50/bbl and to end a 4-day rally after a weekly government report showed oil...

Alberta’s premier seeks more North American energy integration

02/05/2015 Better policy integration and cooperation will be needed for Canada, Mexico, and the US to fully realize the North American energy renaissance’s po...

Deloitte studies oil supply growth for 2015-16

02/04/2015 A Deloitte MarketPoint analysis suggested large-field projects, each producing more than 25,000 b/d, could bring on 1.835 million b/d in oil supply...

Oil, gas infrastructure investments essential, House panel told

02/04/2015 Investments in oil and gas transportation and storage should move ahead because they are essential in continuing the US economic recovery and North...

Petrobras CEO, five other senior executives resign

02/04/2015 Maria das Gracas Foster, chief executive officer of Petroleo Brasileiro SA (Petrobras) since 2012, has resigned along with five other senior execut...

MARKET WATCH: NYMEX crude oil prices reach 2015 high

02/04/2015 Crude oil prices surged more than $3/bbl on the New York market Feb. 3, closing at the highest level so far this year, but some analysts believe th...
White Papers

Pipeline Integrity: Best Practices to Prevent, Detect, and Mitigate Commodity Releases

Commodity releases can have catastrophic consequences, so ensuring pipeline integrity is crucial for p...
Sponsored by

AVEVA’s Digital Asset Approach - Defining a new era of collaboration in capital projects and asset operations

There is constant, intensive change in the capital projects and asset life cycle management. New chall...
Sponsored by

Transforming the Oil and Gas Industry with EPPM

With budgets in the billions, timelines spanning years, and life cycles extending over decades, oil an...
Sponsored by

Asset Decommissioning in Oil & Gas: Transforming Business

Asset intensive organizations like Oil and Gas have their own industry specific challenges when it com...
Sponsored by

Squeezing the Green: How to Cut Petroleum Downstream Costs and Optimize Processing Efficiencies with Enterprise Project Portfolio Management Solutions

As the downstream petroleum industry grapples with change in every sector and at every level, includin...
Sponsored by

7 Steps to Improve Oil & Gas Asset Decommissioning

Global competition and volatile markets are creating a challenging business climate for project based ...
Sponsored by

The impact of aging infrastructure in process manufacturing industries

Process manufacturing companies in the oil and gas, utilities, chemicals and natural resource industri...
Sponsored by

What is System Level Thermo-Fluid Analysis?

This paper will explain some of the fundamentals of System Level Thermo-Fluid Analysis and demonstrate...
Available Webcasts


The Alternative Fuel Movement: Four Need-to-Know Excise Tax Complexities

When Thu, Jun 4, 2015

Discussion on how to approach, and ultimately embrace, the alternative fuel market by pulling back the veil on excise tax complexities. Taxes may be an aggravating part of daily operations, but their accuracy is crucial in your path towards business success.

register:WEBCAST



On Demand

Prevention, Detection and Mitigation of pipeline leaks in the modern world

Thu, Apr 30, 2015

Preventing, detecting and mitigating leaks or commodity releases from pipelines are a top priority for all pipeline companies. This presentation will look at various aspects related to preventing, detecting and mitigating pipeline commodity releases from a generic and conceptual point of view, while at the same time look at the variety of offerings available from Schneider Electric to meet some of the requirements associated with pipeline integrity management. 

register:WEBCAST


Global LNG: Adjusting to New Realities

Fri, Mar 20, 2015

Oil & Gas Journal’s March 20, 2015, webcast will look at how global LNG trade will be affected over the next 12-24 months by falling crude oil prices and changing patterns and pressures of demand. Will US LNG production play a role in balancing markets? Or will it add to a growing global oversupply of LNG for markets remote from easier natural gas supply? Will new buyers with marginal credit, smaller requirements, or great need for flexibility begin to look attractive to suppliers? How will high-cost, mega-projects in Australia respond to new construction cost trends?

register:WEBCAST


US Midstream at a Crossroads

Fri, Mar 6, 2015

Oil & Gas Journal’s Mar. 6, 2015, webcast will focus on US midstream companies at an inflection point in their development in response to more than 6 years shale oil and gas production growth. Major infrastructure—gas plants, gathering systems, and takeaway pipelines—have been built. Major fractionation hubs have expanded. Given the radically changed pricing environment since mid-2014, where do processors go from here? What is the fate of large projects caught in mid-development? How to producers and processors cooperate to ensure a sustainable and profitable future? This event will serve to set the discussion table for the annual GPA Convention in San Antonio, Apr. 13-16, 2015.

This event is sponsored by Leidos Engineering.

register:WEBCAST


Emerson Micro Motion Videos

Careers at TOTAL

Careers at TOTAL - Videos

More than 600 job openings are now online, watch videos and learn more!

 

Click Here to Watch

Other Oil & Gas Industry Jobs

Search More Job Listings >>
Stay Connected