Novel MDF to be made at BP Saltend

A PLANT that will produce a novel, weatherproof form of MDF will be built at BP’s chemicals site at Saltend in the UK.

The 30,000 t/y plant is scheduled to begin production of so-called Tricoya chips in Q1 2019. Production relies on a process of acetylation, which involves changing the hydroxyl groups found within wood into acetyl groups. The problem with hydroxyl groups is that they bind and release water molecules causing the wood to swell, shrink and eventually crack if it is not treated. Removing the hydroxyl groups also makes it 'inedible' to most micro-organisms and fungi which cause wood to rot.

The process has been licensed for use by Tricoya Technologies, which says it will enable MDF to be used outdoors by the construction industry, replacing hardwoods and man-made products in use today.

Pierre Lasson, Tricoya’s general manager, told The Chemical Engineer that the process involves first taking the wood chips used in the manufacture of MDF and soaking them in acetic anhydride that is manufactured onsite by BP. The mixture is then put through what is described as a low-temperature and low-pressure reaction in which the chips are acetylated in a reactor. The hydroxyl groups in the wood react with acetic anhydride to produce acetic acid. This, along with the unreacted acetic anhydride is separated in a distillation column.

“We recover the acetic anhydride and return it to the acetylator reactor, and the acetic acid is stored [for sale],” Lasson said.

“The wood chips then enter a finisher where we remove the last trace of hydrocarbon and then we cool down the wood before shipping the chips to the wood panel maker.”

The new plant is being built by a consortium involving BP, Tricoya Technologies, and wood panel maker Medite.

“The creation of this new consortium provides an exciting new platform for growth for our BP Hull facility”, said Nigel Dunn, vice president of BP global acetyls. “The co-location of the … UK plant with our acetic acid facility creates natural synergies and the foundation for a great partnership.”

The annual production from the new plant will be used to manufacture 40,000 m3 of panel products in a market estimated to be in excess of 1.6m m3, BP said in a statement.

The creation of the new consortium marks 50 years of BP operating in Hull, and is expected to create 30 new jobs.

As well as producing acetic acid and acetic anhydride at Saltend, the site is also home to one of BP’s main research and technology centres.