Going greener offshore

Pei Cheng Chua at the University of Stavanger (UiS) has developed new and better environment-friendly chemicals for use in oil and gas production.

Photo of Pei Cheng Chua in her lab, wearing a coat and protective glasses.

The 32-year-old from Malaysia defended her PhD thesis on studies of new classes of low-dosage hydrate inhibitors (LDHIs) at the university on 24 January.

These chemical substances are used in the petroleum industry to prevent gas hydrate – a kind of hydrocarbon ice – from forming in and blocking pipelines.

Natural gas and produced water can react together under high pressure and low ambient seabed temperatures to create this problem, which can completely halt flow in the worst case.

Various methods are used to overcome the icing, depending on conditions in the various oil or gas fields. In many cases, the simple answer is to add a type of anti-freeze to the hydrocarbons.

The difficulty is that large amounts of water are needed. This does not harm the environment, but costs money, calls for a lot of logistics and poses health risks for offshore workers.

However, scientists have developed LDHIs over the past 10-15 years as an alternative to anti-freeze. They either delay hydrate formation or disperse the ice particles to prevent blocking.

Chua has designed, produced and pressure-tested new LDHIs, which have proved to perform better and/or had less environmental impact than the substances currently on the market.

Some of these products have been patented and are now being subject to further testing by the oil industry before they can be adopted offshore.

Chua previously studied at the Mannheim University of Applied Sciences in Germany, where she obtained an MSc in chemical engineering with top marks.

She has worked for the past three years in the chemical and environmental research team at the UiS, with professor Malcolm Kelland as her supervisor.

Fellow scientists describe her research as outstanding. She has collaborated with five other research teams in Japan, the UK and the USA.

Chua’s thesis comprises 11 separate articles, of which 10 have already been accepted for publication in top-ranking scientific journals.

Read more about green production chemistry.