Methane Gas Venting Pneumatics In Oil And Gas Sites: Solutions And Options
Written by: Ben Klepacki, CRO and Co-Founder, Westgen Technologies Inc.
Gas powered pneumatics have traditionally been used on oil and gas facilities and pipelines as a reliable and low-cost option to control the process through actuated valves and controllers, and power pneumatic pumps. When the high energy gas has been used, it is typically vented to the atmosphere. This venting process, however, releases significant amounts of methane into the atmosphere, which is a potent greenhouse gas with a global warming potential between 25x and 100x that of CO2 (depending on the timeframe considered). It is crucial to eliminate methane venting gas pneumatics from oil and gas sites in order to minimize the environmental impact of these emissions and maintain the sustainability of the industry.
There are several options available for reducing or eliminating methane venting from oil and gas facilities. These include instrument air conversions, electric actuation, and nitrogen. Each solution has its own advantages and disadvantages, and the best approach will depend on the specific needs and resources of each site. Implementing zero venting strategies can also have positive impacts on the bottom line and stock price of companies in the oil and gas industry.
Instrument Air Conversion
Instrument air systems use compressed air instead of natural gas to operate pneumatic equipment. These systems are designed to provide a reliable source of clean, dry compressed air for pneumatic control systems. If your site is grid connected, instrument air conversions tend to be the most economic option available.
Instrument air conversions do have some drawbacks primarily around the need for a reliable source of electrical power and the potential for equipment failure. Larger compressors may be necessary for sites with high air demand, and for remote sites, solar-powered systems may not be practical due to limited sunlight.
There are two main options for sites without easy economic access to power:
Larger scale compressors (2.5 hp and up) tend to be the most economic option to go to zero bleed on sites greater than 3 wells or about 1.5 scfm of air demand. These will typically be packaged with a power generation option that should have enough power to run the rest of your site. On new build (greenfield) applications, this typically allows for efficiencies in the combined package of the air and power generation that allow for excellent economics. In retrofit applications where power might already exist on site, but not in sufficient quantities to power the compressor, the economics can be a bit more challenging as the power generation tends to be the largest part of the instrument air package cost. As a result, larger scale instrument air compressors are typically not economic on smaller sites (3 wells or less) or on sites that demand less than 1.5 scfm. Also always make sure to get a duplex or backup compressor system so that you have redundancy in case of compressor failure.
Self-contained solar powered instrument air compressors are sometimes an economic option below 1.5 scfm. These compressors typically do about 0.5 scfm each and are often based on high efficiency chemical pumps that have been converted to air pumps. While these can be a great option if you don’t want to go with electric actuation, be careful in the selection of your pump. Converted chemical pumps were often designed to make use of the chemical as a lubricant and heat dissipation fluid and this can cause premature wear and high maintenance costs when they’re used as an air compressor.
Electric actuation involves replacing a gas-powered pneumatic valve with an electric motor-driven valve. Due to the high price of electric actuators (particularly in the case of valves where you need a fail position). These tend to be the cost-effective option when the price for the electric actuators is less than any cost you would sink into an air compressor and power generation source. As a rule of thumb, this tends to make sense at the 3 wells or less or 1.5 scfm of existing pneumatic demand or less.
While it should be noted that electric actuation still tend to require more power than you can get out of a traditional solar only or TEG power supply, they are a more energy efficient actuation technology than pneumatics. They also tend to provide a high level of precision in controlling the location of a valve.
The drawbacks of electric actuation primarily center around the high cost of the electric actuators and the slower reaction speed compared to pneumatic valves. This reduction in speed can result in reaction time issues on choke or control valves. Additionally, electric actuators tend to have a shorter lifespan, with fewer cycles before wear and tear occurs. This can be a significant concern in sites with high flowback, where dump valves may need to perform hundreds or even thousands of cycles daily in the initial stages.
Nitrogen conversion is similar to an instrument air conversion in that you are typically able to make use of the existing pneumatics system in a retrofit application. A nitrogen conversion is fairly simple and as a result has few moving parts or components for failure. The simplicity is the benefit and as the majority of costs are in the refilling of the nitrogen, this option typically is economic on smaller sites (3 wells or less or less than 1.5 scfm of demand).
To sum up, there are various solutions available for reducing or eliminating methane venting from oil and gas facilities. The best approach will depend on the specific needs and resources of each site. Implementing zero venting strategies can help minimize the environmental impact of these emissions and maintain the sustainability of the industry. Westgen Technologies is committed to providing innovative solutions to reduce methane emissions from oil and gas sites, and our team of specialists is available to support you in finding the optimal solution for your specific needs.
About Westgen Technologies
Westgen is the North American leader in eliminating methane emissions from pneumatic devices. Each EPOD deployed reduces emissions from the pneumatic system by around 99.5%. A typical EPOD installation eliminates around 40 tons of methane emissions per year. At $1500 per ton, a single EPOD has the potential to reduce your tax burden by around $60,000 per year.
To learn more about Westgen Technologies, contact us at 1-888-609-3763 or by email – email@example.com.