As the old adage goes, one man’s trash is another’s treasure – but the saying extends much further than neighbourly recycling of unwanted furniture or a misjudged gift passed on to a friend. A process known as industrial symbiosis takes the idea of repurposing waste – as the name suggests – to an industrial scale.

The basic principle is satisfyingly simple. Two (or more) factories or process plants located nearby – for example, in an industrial park – use each other’s waste streams as fuel, thus reducing waste and cost for both. In an age where industries measure their success in both economic and environmental performance, it’s easy to see how that appeals to business.

Putting it into practice, though, is not quite so easy.

For a start, there’s the issue of corporate sensitivity. How can one company trust another with specific details of its energy, material and heat needs and, even more so, the makeup of its waste?

 

Kalundborg in Denmark is one of several locations where industrial symbiosis is bringing different industries together to share resources. 

Project EPOS – a four-year EU Horizon 2020-funded project – has come up with a workaround. The project’s PhD researchers have developed blueprints for each energy-intensive sector within the project’s scope – chemicals, cement, steel, minerals, and engineering – allowing companies to share a generic view of their sector’s heat, electricity, and material stream profiles with other companies, scaled to their size, without divulging their site-specific secrets.

 

Professor Greet Van Eetvelde and PhD researcher Helene Cervo explain the EPOS Project.

‘It started with INEOS, where we had a willingness to share our results, to share what we are doing, but not to share our data […] these blueprints are the heart of the toolbox,’ EPOS Project Coordinator, Professor Greet Van Eetvelde explained at a recent briefing on EPOS in Hull, UK. Through access to these blueprints, chief engineers and plant managers can identify opportunities to make best use of their industrial neighbours’ waste streams.

Three companies operating in northeast-England’s Humber Estuary – INEOS, CEMEX and Omya – in the petrochemical, cement, and minerals sectors, respectively – are the first in the UK set to implement the initiative, following research by PhD students based in the UK, Switzerland, Belgium, and France. The wider EPOS project includes clusters in France, Switzerland, and Poland, with ArcelorMittal and Veolia, five SMEs, and two research institutes – École polytechnique fédérale de Lausanne, Switzerland, and Ghent University, Belgium – completing the partnership.

 Overview of the EPOS project

Overview of the EPOS project. 

Currently, INEOS sends waste liquid fuel to its utility provider to produce steam to be fed back into INEOS, while CEMEX derives 20% of its fuel from primary sources – presenting an opportunity for CEMEX to increase its secondary fuel proportion by re-using the waste from INEOS.

In this example, waste liquid fuel from INEOS is separated into acid and high-calorific organic components. The latter can then be delivered directly to CEMEX for use as a fuel, while the former can be fed back into INEOS’ process. 

The researchers estimate that this will deliver equivalent savings of 1,200–1,400 tonnes of CO2 per year. It requires initial investment from both companies, but a payback timeline estimates that the process will break even and then continue to deliver savings in just two years for INEOS and three for CEMEX.

It requires initial investment from both companies, but a payback timeline estimates that the process will break even and then continue to deliver savings in just two years for INEOS and three for CEMEX.

The WISP programme in South Africa is another example of industrial symbiosis in action. 

Before INEOS and CEMEX can begin their industrial symbiosis, however, new permits will be required – some materials currently classified as hazardous waste will require reclassification to be transported and re-used. Professor Van Eetvelde told SCI that it is not investments that will hamper the implementation of EPOS, but waste legislation, which presents different challenges regionally. ‘We need policymakers to come with us,’ she said.