Recent nationwide coverage of the Whitechapel Fatberg has brought the term ‘fatberg’ to prominence, but fatbergs have been a problem in the water industry for a long time.
The 130 tonne, 250 metre long fatberg discovered by Thames Water consisting of, amongst other things, oil, grease and fat, is an extreme example but water companies are regularly reporting similar problems. For example, Welsh Water has recently started a £2 million project to remove a fatberg and fix damage it has caused to the sewers beneath the streets in Cardiff Bay.
In the fight against fatbergs, a team of researchers from the University of British Columbia, Vancouver, Canada has developed a process for converting the fats, oils and grease into useable energy.
What is particularly exciting about the system these researchers have developed is that the process can be undertaken, and the fats, oils and greases turned into fuel, directly in the pipeline.
The process works by heating the fats, oil and grease to between 90-110oC and then adding hydrogen peroxide to break down the organic matter, releasing fatty acids. Bacteria are then used to break down the fatty acids, producing methane.
“It’s a clever idea” says Chad Jafvert, a professor of civil engineering at Perdue University, while also explaining that wider commercial application will depend on cost, specifically the cost of the energy required to heat the materials.
The team at the University of British Columbia are still trialling the process with the aim of developing a full-scale system within two years. It is hoped that after more successful trials the process can be implemented commercially by other sewage treatment systems.