December 29, 2016 by Taylor Miles - Featured
1 Step for the Oil and Gas Industry / Capture Flash Gases from Oil Production / Stop Intentional Methane and Hydrocarbon Pollution
On February 18, 2016, U.S. officials from the state of California announced the natural gas leak from the gas storage facility at Aliso Canyon was stopped and permanently plugged. Between October 23, 2015 and February 18, 2016, 118 days, an estimated 97,100 tonnes of methane and 7,300 tonnes of ethane, which is equal to 5,267,600,000 standard cubic feet (SCF) of natural gas was released into the atmosphere. This leak has been classified as the worst single natural gas leak in the U.S. in terms of its environmental impact. The value of the gas emitted into the atmosphere over 118 days was $17,264,559.00. While Aliso Canyon is a clear example of a deteriorated or inferior design of a gas production well, it was an accident, therefore not intentional and properly classified as a leak.
Excluding oil extracted from tar sands (reference Canada and the Dakota Access Pipeline), all oil and gas is recovered from pressurized underground shale, sand or cavernous reservoirs. A slurry of oil, gas, natural gas liquids and water are forced to the earth’s surface from natural underground storage by high pressure that is accessed through the wellbore. These hydrocarbons are pushed to the surface under pressures up to 6,000 pounds per square inch (PSI) or 414 bar. All oil, condensate and other liquid hydrocarbons that are recovered from these reservoirs contain varying concentrations of natural gas. This gas will remain trapped or dissolved in the liquid, as long as a positive pressure is maintained. At any point in which the pressure on the liquid is reduced or the temperature is increased, gas will begin to escape or “flash” out of its liquid state, thus it’s referred to as flash gas. The amount of hydrocarbon gases that are liquefied in this phase of production and flash out of the hydrocarbon liquid is dependent on the pressure, temperature and the composition at the time it is produced.
Flare gas or fugitive emissions do not include flash gas and are therefore not accurately tracked by the oil and gas industry or regulators. Due to the flaw in the standard design of oil and gas production facilities, these emissions are not an oversight, but an intentional omission. As detailed here, the results are a greater release of gas into the atmosphere than Aliso Canyon and occur daily across the globe. Based on our research, shown below are a few of the world’s major oil and gas producing countries and the estimated methane and other flash gases polluting the atmosphere each day. To provide context, they can easily be compared with the Aliso Canyon leak, which as explained above, has the distinction of being the worst leak of natural gas leak to occur in the US.
|LOCATION OIL PER DAY||SCF FLASH GAS WASTED/DAY||SCF FLASH GAS WASTED/MONTH||ACCUMULATED VOLUME/YEAR|
Results are based on a flash gas volume of 308.1 SCG per bbl. of oil produced.
While the volumes, as demonstrated, are difficult to comprehend, there are experts who believe the volumes could be even higher. These calculations are conservative and based on actual oil production rates, storage tank flash gas rates, gas composition and emission data. All this information was taken in real time, on site, by Newpoint, LLC.
The examples below are the gas composition of these produced liquids when flashed. We used a production pressure of 1,250 PSI and a temperature of 125oF.
|Average Flash Gas Composition||Average Flash Gas Composition|
|No Vapor Recovery Unit||With Vapor Recovery Unit|
|0.073 Nitrogen||0.008 Nitrogen|
|1.412 Carbon Dioxide||0.659 Carbon Dioxide|
|33.81 Methane||9.023 Methane|
|20.77 Ethane||17.45 Ethane|
|19.81 Propane||31.96 Propane|
|3.51 Isobutane||6.88 Isobutane|
|9.57 n-Butane||18.72 n-Butane|
|2.888 Isopentane||4.613 Isopentane|
|8.157 n-Pentane+||10.7 n-Pentane +|
|100 Total||100 Total|
Based on a daily oil production rate of 8.52 million barrels, the U.S. intentionally wastes 2,620,082,400 scf of methane, ethane, propane, butane and pentane gas every day. As with Aliso Canyon, the gas contaminating the atmosphere is only visible using an infrared camera. Unlike the Macondo Deep Water Horizon disaster that occurred in the Gulf of Mexico in 2010, which had both oil and gas, the oil could be seen and so the perception of the disaster was greater and therefore received more public attention.
Below we have provided the actual value of the gas wasted as well as an equivalent value in electric power and gallons of gasoline.
|LOCATION OIL PER DAY||SCF FLASH GAS WASTED PER DAY||40W LIGHT BULB, CONTINUOUS SERVICE||GASOLINE EQUIVALENT,GALLONS PER DAY|
BTU of Flash Gas is 2,045. Value / based on $2.89 per MMBTU or $5.91 per MCF
While most areas in the world ignore this issue to the detriment of us all, it is not the case in Nigeria. We are working with their government officials, as well as private companies, to see these flash gases captured and converted into electric power. The objective here is twofold; eliminate the continuous contamination of the environment from these hydrocarbons and utilize it as fuel gas to generate power. The positive impact from this effort will be immeasurable. If these wasted resources were captured and utilized the environment and everyone would benefit.
The atmosphere is becoming contaminated with these greenhouse gases (GHG) at a much higher rate than is being projected. Energy regulators, along with the scientific community have never identified and properly estimated raw flash gas emissions as a source. Based on our experience and research, by adding flash gas, projections of atmospheric GHG concentrations can be more accurately projected.
The problem is not complex and the solution is not a technical riddle that can’t be solved. As with any problem, the first step to implementing a solution is to simply reach an agreement. An agreement that flash gas is a major GHG contributor by the regulatory and scientific communities, as well as oil and gas executives, will give credit worthy solution providers access the funding that is required.
This influence on the investment community will also indicate implementation of a process that has a positive impact on the environment. While the reduction of GHG emissions is the focus, it will also represent the generation of power, particularly in some of the world’s poorer countries which are desperate for the luxuries we take for granted.
Eradication of flash gas into the atmosphere is the focus of our efforts at One Step In. We need your help and influence to spread the word so the powers in the highest places hear our message. Please get involved now!
For more information on the Vast Limitations of Vapor Recovery and the waste of Flash Gas, Natural Gas Liquids and Liquefied Petroleum Gas, please see papers on these subjects at www.onestepin.org.
Wiley Rhodes, Founder