Processing bulky household, construction and demolition waste
Bulky household waste and building and demolition waste still contain a lot of valuable raw materials. At Twence, we extract a great deal of materials from these that can be reused. How does that process work in practice?
This is how we process bulky household, construction and demolition waste
The waste that is produced during construction and demolition is processed by Twence. We also receive bulky household waste that is collected from waste collection centres, that is left over from recycling companies, or that is recovered from house clearances, for instance. In order to extract valuable materials from the waste, we first sort out the waste. This is done in our waste separation plant. From there, the waste either goes on its way internally or finds it way to processors that recycle the raw materials or process them into new products. This waste is converted into raw materials and energy in our internal conversion processes.
We need no less than three plants to process this bulky waste: the waste separation plant, the biomass power plant and the waste-to-energy plant. The following diagram shows at a glance what kind of bulky waste we handle, which plant it goes to, what we make out of that input and who we ultimately deliver these new raw materials and energy to. After that, we provide a brief explanation of the most important plants.
Waste separation plant
We recycle construction and demolition waste and bulky household waste into reusable partial streams in our separation plant. These streams include metals, wood, rubble, sand, carpet, plaster, paper, cardboard, plastics, glass, etc. The various separation techniques based on size, shape, weight, colour, magnetism and also done by hand, enable us to recover a large proportion of these materials. Materials that are not recyclable after separation are used as fuel in our waste-to-energy plant, or - in the case of wood waste, for example - as fuel for the biomass power plant. Recyclable materials are made suitable for reuse by external parties.
Waste-to-energy Plant
Waste that cannot be further sorted or recycled is sent from the waste separation plant to our waste-to-energy plant. After incineration, bottom ash is left behind which is processed in our bottom ash plant
into new raw materials. The incineration process generates a lot of energy. We convert this energy into sustainable energy: steam, hot water and electricity for the region. The flue gases that are released we clean as much as we possibly can.
Biomass Energy Plant
In the biomass power plant, we burn the wood from the waste separation plant that is not fit for recycling. The boiler walls of the BEP are fitted with water-filled pipes that convert the heat from the fire into steam and hot water. We also use them to generate electricity. Given that the combustion material does not contain any fossil fuels, this electricity is deemed to be 100% green. We supply the electricity, steam and hot water to the region as sustainable energy.
Sales distribution to external processors
Alongside our own processes, we also offer recyclable partial streams to external processors. For example, paper and cardboard go to a regional paper recycler, and carpet fibres can be used in new cradle-to-cradle carpets. Gypsum, too, lends itself perfectly to a second life and glass is even endlessly recyclable. The better we are at separating valuable raw materials from waste, the bigger the steps that we can take towards a circular economy.
And this is what we make out of bulky household waste and construction and demolition waste!
