# Measuring Gas Flaring in Russia with Multispectral VIIRS Nightfire
## 4 Discussion
### Effect of Gas Processing  
Vankor oilfield, located at 67\({}^{\circ}\)48\({}^{\prime}\)N 83\({}^{\circ}\)32\({}^{\prime}\)E in Krasnoyarskiy Krai and commissioned in 2009, has been one of the largest oil producing fields in Russia in recent years. In 2013, its annual oil production volumes reached 21.4 million metric tons [53], which is comparable to the Samotlor oil field (22 million tons) [31], the second largest oil producing field in Russia at the time. In 2018, Vankor remained the third largest oil producing field in Russia (16 mln tons per year) [45]. Yet, prior to October, 2013, the APG utilization rate at the field, according to \"CDU TEK\", remained lower than 1% [54]. In 2013, the total gas extraction volumes of the Vankor field were reported to be 6.55 BCM [55], with only 0.62 BCM classified as natural gas [53]; i.e., APG production volume was approximately 6 BCM, which, due to low utilization, was mostly routed to be flared at the gas flaring facilities of the field. In late 2013, commissioning of the APG reinjection system resulted in a 17% APG utilization rate by December [53]. In April 2014, the field was connected with the Gazprom gas pipeline system, which resulted in a 61% annual APG utilization rate in 2014 and 88% utilization in 2015 [56]. The required 95% APG utilization rate at the field was reached in 2018, as 98% of extracted APG is reported to be utilized [57]. The dip in gas flaring since April-May of 2014 is evident from the Nightfire data as well, as can be observed in Figure 10c (note the gaps in observation caused by the midnight sun period of the subpolar regions). It presents a flaring dashboard for one of the two major gas flaring facilities at the Vankor field (ID 20212_20585 from the gas flaring catalog), which was estimated to be the largest flare in the world in 2012 according to Nightfire. If, prior to 2014, Vankor gas flaring facilities were detectable during any valid night-time VIIRS observation, ever since 2014, the detection frequency has dropped below 100%, and the average daily estimated flaring volumes have dropped by an order of magnitude. Persistent surges in flaring in April and May in the following years can be attributed to maintenance procedures. Figure 9: VIIRS Nightfire gas flaring data dashboard for the case study gas processing plant (GPP) in Khanty-Mansi Autonomous Okrug, Russian Federation (62.35\({}^{\circ}\)N 74.32\({}^{\circ}\)E). (**a**) High-resolution image of the GPP available in Google Earth. (**b**) Recording of fire at the GPP, available from the news outlet. (**c**) VIIRS Nightfire day-to-day dashboard for a field related to the GPP under consideration, including 1��⃝ spectral radiance in M10 SWIR channel of VIIRS, 2⃝ mean estimated temperature of successful detections (in K), and 3⃝ mean estimated radiant heat \(RH\) (in MW). Note the shaded area in 3⃝, which corresponds to summer-time gaps in observations discussed in more detail in Section 4.4. Figure 10b presents the correlation of Nightfire-estimated flaring volumes from all detected gas flaring facilities at the Vankor field (major flaring facilities are oil treatment unit ID 2012_20585 (67\({}^{\circ}\)48\({}^{\prime}\)N 83\({}^{\circ}\)33\({}^{\prime}\)E) and oil dehydration and desalting unit ID 2012_20589 (67\({}^{\circ}\)43\({}^{\prime}\)N 83\({}^{\circ}\)30\({}^{\prime}\)E) from the gas flaring catalog) and reported data compiled from Rosenft annual reports (which present annual APG production levels and utilization rates for Vankor and surrounding oil fields, with the latter being commissioned since 2016, introducing the noise in the data), as well as the RUPEC report which presents \"CDU TEK\"  
Figure 10: VIRS Nightfire gas flaring data dashboard for the southern oil dehydration and desalting unit of the Vankor oil field in Krasnoyarsk Krai, Russian Federation (67\({}^{\circ}\)43\({}^{\prime}\)N 83\({}^{\circ}\)30\({}^{\prime}\)E). (**a**) High-resolution image of the oil dehydration and desalting unit available in Google Earth.