Flaring has been common practice in the oil and gas industry for over 160 years. It is done for numerous reasons, but most commonly it is a way of disposing of the associated natural gas from oil production where there is no infrastructure for gas takeaway. What most people outside the industry do not understand is that flaring is a cost effective and efficient means of burning vented natural gas, and therefore reducing greenhouse gas (methane) and VOC emissions. The new EPA 0000 rules seek to put measures into place which help ensure the efficiency of flare units on oil and gas facilities. In doing so, they have set forth a complex set of compliance obligations which operators must now adhere to.
The building of pipeline infrastructure for removing the natural gas associated with oil production and transporting it to facilities where it can be processed and sold is very expensive and often, logistically impossible. The infrastructure for a given area of operations can represent hundreds, if not thousands, of miles of pipelines. Laying that pipeline requires land and right of ways that often cannot be obtained. Even if the land and right of ways can be obtained, the expense of building the pipeline can make individual well production economically infeasible. Operators therefore utilize flaring as an affordable means of removing the natural gas in an environmentally responsible manner.
Studies, such as the Texas Commission on Environmental Quality (TCEQ) Flare Study[1], have shown that when operated properly, natural gas flares can achieve a high percentage of Destruction Removal Efficiency (DRE) of the constituents within natural gas. The primary driver in achieving high DRE is the heating value of the gas being burned. The newly released EPA rules require the operator to demonstrate that the heating value is above a specified amount to ensure a minimum of 95% DRE. The heating value requirements differ depending on the flare type. The rule requires that a minimum of two samples of the flare gas be collected and analyzed per day over a 14-day period. If the heating value of that gas is less than 1.2 times the specified operating limit, continuous monitoring may be required. It is therefore imperative to obtain accurate and defensible heating values in order to avoid costly and labor-intensive continuous monitoring programs.
One of the major challenges is that most flares which do not have a dedicated volumetric meter are not set up for gas sample collection. As a result, an appropriate location must be determined, and a sample probe installed to ensure the collection of a representative sample from the flare gas stream. If multiple pipelines feed a single flare, there may not be a location where a representative sample of the commingled gas can be collected, necessitating individual sample locations for each stream. Each flare will therefore need to be assessed by knowledgeable personnel, prior to the arrival of the sampling team, to determine the sample location(s) and perform the necessary fabrication to install the sample probe(s).
In accordance with the new rule, the minimum time for collection of each sample must be at least one hour. This requires short period, flow weighted, composite samples to ensure it is representative of the gas which flowed through the flare line during that one-hour period. The sampling system must be maintained above the hydrocarbon dewpoint of the flowing gas at all times during sample collection in order to avoid sample distortion. Sample containers must be handled in a manner that ensures sample integrity. Once back at the laboratory, samples are required to be analyzed and heating values calculated in accordance with ASTM D1945–14, Standard Test Method for Analysis of Natural Gas by Gas Chromatography.
The sampling and analytical associated with the new EPA 0000 flare heating value determination requirements are complex. SPL is uniquely positioned to provide the complete solution for ensuring compliance. We have over 250 field technicians and 15 hydrocarbon laboratories providing services to every major US area of operations. We are the recognized technical leaders in sample collection and hydrocarbon analysis. Our team of experts will walk your site, determine the appropriate location(s) for collecting a representative sample(s), fabricate the necessary connections, and install the sample probes. We will collect the required number of samples in accordance with rule and industry standards, ensure they remain undistorted from sample collection to analysis, and analyze them in accordance with ASTM D-1945-14, providing our customers with accurate and defensible heating values and, most importantly, peace of mind.
[1] David T. Allen, P. V. (2010). TCEQ 2010 Flare Study, Final Report. Austin, TX: The University of Texas at Austin.
Dave Curtis
Chief Revenue Office
Dave Curtis is the Chief Revenue Officer (CRO) at SPL since April 2022, driving revenue growth and strategies. Previously SPL’s Chief Technology Officer, he brings diverse experience in corporate strategy and over a decade at Anadarko Petroleum. Dave holds a Master’s in Civil Engineering from Norwich University (2015), showcasing his commitment to continuous learning. With expertise in technology, strategy, and revenue generation, Dave is a seasoned leader at the forefront of SPL’s success.
