Have you ever wondered what happens to waste once it leaves King’s? For recycling, the answer is in the name: once it is collected, it is sent to a Materials Recovery Facility (MRF), separated by type and quality, and packed up to be turned into new products. Last year, we visited Veolia’s MRF in Southwark, London, to have a look at the processes involved. You can read about our experience (and see us all in high-vis and hard hats) here.
But what happens to all the stuff that can’t be recycled?
This summer, we visited Grundon to find out. Grundon collect waste from King’s laboratories that cannot be recycled or recovered through traditional methods. Instead, it has to be incinerated at high temperatures in a clinical waste incinerator. In two chambers, the waste is burned for several hours and at temperatures of up to 1,100 degrees Celsius. Gases are cleaned through a gas scrubbing system to reduce emissions of pollutants such as CO2. The heat produced through this process passes through the boiler and creates steam, which is exported to their Energy from Waste (EfW) plant nearby, and used to power a steam turbine generating electricity.
After our visit to the clinical waste incinerator, we toured Grundon’s Energy from Waste plant. This is where general waste (e.g. the black bins at King’s, containing sweet wrappers, sandwich cartons, plastic film etc.) is processed. While general waste at King’s is collected by Simply Waste Solutions, not Grundon, the process is the same.
Waste is collected in a tipping bay, where a crane picks it up and feeds it into furnaces. Like in the clinical waste incinerator, the heat generated is used to power a steam turbine generating electricity. The EfW plant we visited processes over 410,000 tonnes of waste every year, and generates 37 MW of electricity. A small proportion of this electricity is used to power the plant itself, while the remaining electricity is fed into the National Grid – enough to power approximately 50,000 homes.
The ash that remains at the end of the process is used for road surfaces. This means that even though some things can’t be recycled, we can keep them out of landfill by using them to create energy.
If you want to find out more about recycling at King’s, you can head to internal.kcl.ac.uk/waste, where you will find our full recycling guidelines.