Marco Puglisi, AEREON Europe, Italy, examines applications, equipment and technical solutions for gas recovery packages in the oil and gas sector.
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n recent years, the oil and gas industry has been under a lot of pressure from environmental regulatory agencies worldwide to sensibly reduce the emissions of pollutants into the atmosphere. Regulatory attention has been focused not only on the reduction of the emissions of toxic and hazardous substances, but also on the reduction of greenhouse gas emissions – such as methane and carbon dioxide (CO2) – that in the long-term have been proven to have a harmful effect on the environment. The development and installation of gas recovery packages in various upstream, midstream and downstream applications of the oil and gas industry is an initiative in the aforementioned direction. Gas recovery packages are process units aimed at recovering and re-using the gas that would otherwise be either emitted to the atmosphere or thermally destroyed in a flare or thermal oxidiser.
Applications In the upstream sector, gas recovery units find application in well-head compression facilities. They allow for the continuous and stable production of compressed gas delivered to the sales pipeline, and enhance the life cycle of the well. The benefits of the installation of a gas recovery unit in a well or group of interconnected wells are evident, as it
provides a positive return on investment (ROI) thanks to the economic value of the recovered gas. Moreover, its presence allows for the operation of sites where flaring is restricted or not permitted. In the midstream sector, gas recovery units are utilised to recover the flash gas that originates from heaters-treaters, phase separators or during crude oil stabilisation process/storage. Typical examples are the dehydration process of well gas with ethylene glycol, and the light ends (C1, C2) removal from crude oil during the stabilisation process. In the downstream sector, gas recovery units are typically utilised in refineries or petrochemical plants to recover gas that otherwise would be flared; for this reason, they are called ‘flare gas recovery units’. A flare is a piece of equipment that is considered as a ‘safety device’ in refineries, petrochemical plants and oil and gas production/transformation sites. It provides safe and effective disposal of toxic and harmful gas during plant emergencies or upset conditions, such as fires, blocked outlets, control valves failures, cooling water failures, electric power failures, instrument air failures or runaway chemical reactions. A flare produces continuous flaring by collecting and disposing of process gas vented during start-up and shutdown, process transitions, and pressure safety valve (PSV) vents.
HYDROCARBON 43
ENGINEERING
February 2022
