Quantification of methane emission rate from oil and gas wells in Romania using ground-based measurement techniques

Abstract

The ROMEO campaign (ROmanian Methane Emissions from Oil and gas) focused on measurements of methane (CH4) emission rates from oil and natural gas (O&G) production in Romania. The campaign took place in October 2019 and covered the southern part of Romania around the cities Bucharest, Ploiesti, Pitesti, and Craiova. This study presents emission rates calculated from mobile in situ measurement of CH4 and wind measurements using the Other Test Method 33a from U.S. Environmental Protection Agency and the Gaussian Plume Method. These methods were used to determine emission rates from 112 O&G well sites and other production-related facilities. Estimated mean CH4 emission rate with a 95% confidence interval equals 0.49 [0.35, 0.71] kg CH4 h−1 per site; 10% of all quantified sites account for 56% of the estimated emission rates. In addition, more than 1,000 O&G sites were visited for a qualitative “screening” (CH4 detection without quantification). Analysis of the screening data shows that 65% of the sites emitted methane at detectable rates. The CH4 emission rates obtained during the ROMEO campaign are comparable to the methane emission rates in study carried out in other Romanian regions.

Supplementary material to "High potential for CH4 emission mitigation from oil infrastructure in one of EU’s major production regions"

“…The Other Test Method (OTM) -33A dataset and application during the ROMEO campaign was previously described in (Korbeń et al, 2022). OTM-33A is based on stationary observations of the mole fraction of trace gases, and quantification using wind direction and speed.…”

“…Measurements with the Gaussian Plume Method (GPM) were additionally performed by the two teams carrying out quantifications using the TDM and OTM-33A approaches as mentioned in the above sections, and the GPM dataset and application during the ROMEO campaign was also described in detail in (Korbeń et al, 2022) and (Delre et al, 2022).…”

“…The mole fraction of the gas at any point, and eventually the emission rate, can be calculated by using information about the height of the source, wind speed and wind dispersion parameters (Riddick et al, 2017) and applying Eq. 2 (Turner, 1970;Korbeń et al, 2022).…”

“…As stated in the main text, we do not apply this correction to GPM measurements, since a comparison to TDM is not possible for the other measurement teams (Korbeń et al, 2022).…”

“…analyser. Similarly, when the OTM-33A could not be applied, either because the topographic conditions were not suitable or because the wind conditions were not appropriate, the GPM was applied (Korbeń et al, 2022).…”