Minox Technology provides cost-efficient gas dehydration with a smaller footprint
As operators look to make platforms and refineries smaller, leaner and more efficient, gas dehydration systems have been a key area of innovation in recent years. Typically, drying wet gas requires bulky and expensive steel dehydration towers which can be as high as 30 metres, weigh a great deal and take up valuable room, especially on a platform.
As a result, technology developers have sought to miniaturise these systems. In early January, for example, ExxonMobil licensed its cMIST technology to Sulzer. This dehydration system uses a droplet generator and proprietary in-line separator technology to reduce the footprint needed to dry produced gas.
Norway’s Minox Technology has also proposed a revolutionary approach to the issue, and following a successful large-scale testing operation, has launched its own patented technology. The Minox®DryGas system uses compact components alongside state-of-the-art static mixers and scrubbers, all of which are built into small compact modules to reduce overall size.
Minox, a process technology company based in Notodden, has previously marketed produced compact deoxygenation (deaeration) systems for oil and gas, used to treat water prior to injection into oil producing reservoirs.
The DryGas system uses two separators, each with a static mixer mounted upstream, in combination with triethylene glycol (TEG) for moisture extraction. This approach reduces the size and weight of the system by 50-70% compared with conventional drying towers, offering major benefits for space-sensitive offshore applications.
The system also requires less TEG in circulation than conventional contactor towers, in addition to a very low pressure drop. This too offers a reduction in size, weight and energy consumption of the TEG regeneration units, again helping to reduce both Capex and Opex.
Minox also says the system can play an enabling role in subsea gas dehydration – another key area of research for major technology backers, including ExxonMobil.
The recent trial was conducted in partnership with Statoil and the Norwegian Research Council, and supported by 5.3 million kroner (US$650,000) in funding from the latter’s Demo2000 programme. Tests were undertaken at Statoil’s K-lab test centre, in Kårstø.
According to a June update from the company: “Test results were very convincing, and the Minox®DryGas technology was consequentially approved by Statoil to be ready for first commercial use. The technology is obviously well suited for greenfield projects, but due to the system’s design and flexible installation methods, it is very well suited for the brownfield market including upgrades, extensions, [and] performance improvements.”
The DryGas system has approved patents in Norway, UK and Brazil.