Monitoring of associated petroleum gas flaring using space imagery

Flaring of associated petroleum gas (APG) is one of the most urgent problems in the oil and gas complex nowadays, which consists in causing environmental, social and economic damage to the state. APG is a mixture of various hydrocarbon gases contained in oil. In natural conditions APG is located in oil reservoirs and comes to the surface in the process of oil production. The main difference between APG and ordinary natural gas is that it contains not only methane, but also heavier gases such as butane, propane, ethane, etc., as well as other unnecessary components: helium, argon, hydrogen sulfide, nitrogen and carbon dioxide.

The flaring of associated petroleum gas does not go without a trace for the environment. The flaring of associated petroleum gas causes damage to the environment. In the process of APG flaring, a huge amount of toxic compounds are released into the atmosphere, stimulating global destructive processes in the environment. Based on current statistics, due to APG flaring in Russia and Kazakhstan alone, more than one million tons of polluting components are emitted into the air per year, which are hazardous to human health on a national and global scale. In addition, APG combustion is wasteful to the economy, as it can be used as a raw material in the energy and chemical industries. APG has significant calorific value, and methane and ethane, the individual components of associated petroleum gas, can be used in the production of rubber and various plastics. Substances remaining from APG in the final processing are suitable raw materials for the creation of liquefied gases and fuel additives. Since 2008, the Russian Government has been actively working to improve energy efficiency of the country's economy. One of the most important tasks of the fuel and energy complex is to solve the issue of efficient APG combustion. In particular, the RF Government Resolution No. 7 dated January 8, 2009 set the target value of associated petroleum gas flaring for the following years at no more than 5% of the total produced volume. However, little success has been achieved so far in solving such a complex problem, as there are still no mechanisms in place to accurately account for the volumes of flared gas. Mass media and oil and gas companies give very different values about the volume of utilized APG, and there are also contradictory actions at the state level. The largest volumes of APG flaring are in Russia, despite the fact that this issue is relevant for all countries with developed oil production. APG flaring in Russia is significantly higher than the global average and more than twice as high as in Nigeria. According to various sources, 15-35 billion cubic meters of APG are flared in Russia every year. In addition, more and more regions in our country are flaring APG, which is becoming a major factor of environmental pollution. At the same time, major oil and gas companies have started to move in the right direction. The World Bank (WB) reported that the global volume of associated gas flaring decreased by 7.1 billion cubic meters in 2017, and it was Russia that became the world leader in reducing APG flaring, decreasing it by 2.5 billion cubic meters. Earlier, the WB reported on the negative "records" achieved by the leaders of APG flaring and the significance of such waste: the volume of associated petroleum gas flared in 2015 would be enough to cover the energy needs of all African countries. Penalties for flaring APG The Ministry of Energy of the Russian Federation has proposed to toughen the system of penalties for flaring associated petroleum gas, it follows from the letter of Pavel Sorokin, the deputy head of the agency, to the Ministry of Finance of the Russian Federation dated December 23, 2019. Currently, producers are fined if less than 95% of APG is utilized, and the Ministry of Energy is in favor of working out the issue of raising this level to 97.5%, i.e. introducing fines for flaring more than 2.5% of gas.

Monitoring of APG flaring volumes Earth remote sensing (ERS) systems have proven to be a good tool for monitoring APG flaring volumes. Some satellites are equipped with devices that can acquire data in the thermal and infrared ranges. The temperature emitted during gas combustion is very high, therefore, the information received from satellites can be used to determine the condition of flares and estimate the volume of gas flaring.

The thermal range allows very accurate estimation of the underlying surface temperature, but the spatial resolution of such instrumentation is too low to accurately detect flares, which are extremely small in size. 

Therefore, it is necessary to use IR data with a higher spatial resolution, which can be as high as 1.2 m. The technology of using IR data is based on the strong difference between the temperature of flares and the temperature of the whole environment. As a result, temperature "flares" appear on the image, which, if properly classified, can be easily identified as flares of associated petroleum gas.

Determination of APG flares The accuracy of detection of APG flares from space images reaches 98%. The remaining 2% of gas flares from space may be natural and anthropogenic fires, which are difficult to distinguish using only IR-band imagery. The intensity of gas flares can be determined by the brightness and area of thermal "highlights" in the images. And having a lot of multi-temporal remote sensing data (ideally for each day) it is possible to estimate flaring volumes for the observation period and identify violations of the current legislation.