Sasol and Cambi innovate to move up the waste hierarchy through thermal hydrolysis

Cambi has signed a large contract with Wood, a global leader in consulting and engineering, to supply Sasol with two full-scale thermal hydrolysis process (THP) systems for treating industrial biological sludge at Sasol’s Secunda Operations (SO) in South Africa.

Sasol and Cambi commenced a commercial trial at SO in 2021 using a small-scale THP unit. Extensive laboratory tests and integration checks demonstrated the feasibility of refunneling industrial biological sludge into Sasol’s coal-to-liquids (CTL) gasification process and identified the optimal process parameters for full-scale application.

Cambi THB Pilot 1200 x 630

Photo: Cambi’s THP pilot unit for the commercial trial at Secunda Operations

“We are excited about this project, as it will enable us to improve our waste management by moving up the waste hierarchy while improving ambient air quality. This will enable Sasol to move away from incineration and, at the same time, to derive syngas from biosludge. We recognise the link between our activities and the need to act responsibly by holistically managing the impacts of our operations through world-class innovation,” said Simon Baloyi, Executive Vice President for Energy Operations and Technology at Sasol.

“Today’s contract is important for Cambi, marking our first full-scale THP project for industrial substrates outside of Norway. The project is unique in the world and introduces a new, sustainable way to process large streams of biosludge. The swift progress from demonstration to full-scale adoption shows that THP makes business sense in many settings and is testimony to Sasol’s solid commitment to reducing carbon emissions. We look forward to seeing the full-scale solution in operation as soon as possible”, remarked Eirik Fadnes, CEO at Cambi.

This innovative project will reroute biosludge from incineration to the gasification process, thereby reducing point source emissions. It will be the world’s first full-scale installation where thermal hydrolysis is used to enable the conversion of biosludge into hydrocarbon fuels and chemicals.

The THP equipment supply contract follows an engineering design project carried out by Cambi earlier this year in close collaboration with Wood, who were commissioned to deliver the full sludge refunnelling solution.

For Cambi, the project is ready to go into the manufacturing phase. The two THP systems are scheduled for commissioning in 2024.