Mouritsen A/S participates in project on optimising chemical use in the oil and gas industry

When oil and gas are extracted from underground, hydrogen sulphide naturally follows.

However, hydrogen sulphide is corrosive, flammable, and toxic, so it is necessary to remove hydrogen sulphide from the gas. To do this, so-called H2S scavenger chemicals are added, but there is great potential for the oil and gas industry to reduce the use of scavengers - for both financial and environmental reasons.

Mouritsen A/S has therefore participated in the project SCAVOP together with Crossbridge Energy, TotalEnergies Denmark, Aalborg University and Rambøll Denmark, which developed a simulation model for how operators in the oil and gas industry can optimise the addition of H2S scavengers. The model provides a clear picture of how H2S scavenger is absorbed into gas from the subsurface when it is pumped ashore.

40 metre long pilot installation

In connection with the SCAVOP project, Mouritsen A/S established an almost 40 metre long pilot plant to test different injection methods.

For financial reasons, it was not possible to establish a plant with gas, H2S and MEA Triazine. Instead, CO2 and sodium hydroxide - caustic soda - were used as chemical reactants. In the plant, sodium hydroxide was injected into an air stream with three different injectors - one type of quill and two different atomisers. The CO2 content of the air was then measured.

"It has not been possible to establish a pilot plant that was chemically identical to the reality on a production platform, so the task has been to establish a plant where CO2 and caustic soda could be used to create comparable processes that the researchers from Aalborg University could use for their calculations and models,"

says mechanical engineer Martin Bæk, Lead Engineer Offshore at Mouritsen, in a special edition of Maskinmesteren , which has published a major article about the project.

Great potential

The SCAVOP project results indicate that optimised processes and injection methods can halve the amount of MEA Triazine used in the H2S scavenger process.

"Generally, MEA Triazine is overdosed to ensure that you reach 3-5 ppm hydrogen sulphide in the exported gas. But large overdosing is of course an expression of a process that is not very precisely controlled. The scavenger process must be subordinate to the other production conditions, and this offers great potential for process optimisation," says Martin Bæk in the same article in Maskinmesteren.

In addition to providing facilities for the pilot plant, Mouritsen A/S has collaborated on the trials with Aalborg University.

"Our fleet of equipment includes compressors, air handling units, flow meters, filters, high- and low-pressure pumps and containers to be used for the pilot plant,"

Martin Bæk explains and continues:

" As suppliers to the offshore industry, we are naturally always interested in new methods and tools that can help the industry do better business and make their operations more sustainable. Therefore, it makes sense for us to participate in a project like SCAVOP, which may help optimise important processes for our customers," says Martin Bæk to Maskinmesteren.