Monitoring harmful emissions during shale gas operations
20 February 2015
There is some concern about the environmental effects of shale gas hydraulic fracturing (fracking) operations across the globe. These often come from scrutiny of shale gas operations in the United States, where fracking has been taking place on a large scale for years. This article by Steve Beynon of FLIR Systems looks at existing and possible future regulation of the sector, with a specific focus on the use of optical gas imagers to detect VOCs during fracking operations and help operators mini
Frack pad in Poland - Image: Shutterstock
Those keen to publicise the negative environmental consequences of fracking most often point to potential contamination of water sources, but the effects of diffuse volatile organic compound (VOC) emissions to the atmosphere from production, transport and storage facilities are an increasing issue.
Diffuse VOC emissions to the atmosphere can be caused by escaping gas from fracking operations, both in the exploration and production phases, as well as by remote gas escaping from natural cracks or fissures in the ground. Other than the environmental implications, there are serious safety concerns about uncontrolled gas releases that could result in potential explosions.
One of the most significant advances in infrared thermographic camera technology over recent years has been the introduction of optical gas imaging (OGI) cameras. These use spectral wavelength filtering and sterling cooler cold-filtering technology to visualise the infrared absorption of VOC/hydrocarbon gases. By using a camera with this functionality, the operator can visualise leaking gas and pinpoint it to its source from a safe distance. OGI technology also now offers 'Smart Leak Detection and Repair (LDAR)' programs that can safely visualise gas leaks quickly and efficiently. Previous methods took many hours, or even days.
Within the EU, there are no specific regulations for controlling and limiting VOC emissions from fracking operations. This activity was not recognised, for example, in the recent EU Industrial Emissions Directive (IED). However, in October 2014, the EU Commission released guidelines which outline the Best Available Techniques (BAT) for monitoring diffuse VOC emissions to air in the Oil and Gas refining sector.
Since the refining and fracking industries have many similarities, the EU Commission may in future consider recommending the same technologies for the latter. Recent studies certainly support this consideration, especially the use of optical gas imaging.
The EU regulation Refining of Mineral Oil & Gas BATC (1) recommends using a combination of technologies to complement each other. OGI and sniffing technology should be used for 'localised' inspections, whereas techniques such as DIAL (Differential Absorption Light detection and ranging) and SOF (Solar Occultation Flux) are for a more 'global' measurement of VOC releases from a facility.
In July 2014, the UK Environmental Agency published the document 'Considerations for quantifying fugitive methane releases from shale gas operations', specifically for the fracking industry. In this document the agency specifically refers to the use of OGI cameras.
The document clearly states that the agency will be responsible for enforcing regulations, but it seems likely the EU Commission will drive the regulation process forward. This makes sense as the UK can share experiences with other EU countries such as Poland which are also in early the stages of developing fracking operations.
Optical gas imaging camera in use - Image: FLIR Systems
In a recent communication from the Commission on the exploration and production of hydrocarbons (such as shale gas) using high volume hydraulic fracturing in the EU, the establishment of a European Science and Technology Network on Unconventional Hydrocarbon Extraction was announced (2), bringing together practitioners from the industry, research, academic and civil society.
The main objective of the network is to collect, analyse and review results from exploration projects, as well as to assess the development of technologies used in unconventional gas and oil projects. The network will also be complementary to other related Commission initiatives, in particular to the revision of the Best Available Techniques Reference document (BREF) on the management of extractive waste (ongoing), the development of a new BREF on hydrocarbon exploration and production (to be launched), the exchange with Member States in the Technical Working Group on environmental aspects of unconventional fossil fuels and EU-funded research activities. The review and development of the BREFs will gather representatives from Member States, industries concerned and non-governmental organisations promoting environmental protection.
In the UK Environment Agency document, there are references to the work that has taken place in the United States, which has been the leading exponent of onshore fracking operations, and where OGI was adopted at an early stage. There, the US Environmental Protection Agency (EPA) has issued federal and state regulations governing the sector.
One of the key stages where OGI can be of benefit is within the 'Green Completion' or reduced emissions completion stage of shale gas extraction. This follows the exploration and start of production stages, and allows for the safe and environmentally sound production and processing of shale gas for storage or transportation. Green Completion has been noted in the recent US Federal regulation update 40 CFR Part 60 Subpart OOOO (QUAD O) published in the Federal Register on August 16, 2012. The final rules include the first federal air standards for natural gas wells that are hydraulically fractured, along with requirements for several other sources of pollution in the oil and gas industry that were not regulated at the federal level.
As is already the case in the USA, it seems clear that optical gas imaging will also in future play a key role in monitoring fugitive VOC releases from fracking sites and associated infrastructure in the EU.
(2) Reference source: https://ec.europa.eu/jrc/en/uh-network : EU initiatives