10181020Resource-Efficient Conversion of Incinerator Bottom Ash into Sustainable Aggregates Using Novel Binder TechnologyClosedCollaborative R&DInnovate UKThe residual waste that remains after the recyclable fraction has been removed from municipal solid waste, is increasingly being combusted in energy from waste (EfW) facilities in the UK. This produces a large amount of incinerator bottom ash. Approximately 2.5 million tonnes of this are currently produced in England and Wales each year. Ferrous and non-ferrous metals are extracted from the ash for recycling. The remaining mineral fraction (~80 wt.%) has potential to be used as aggregate in a wide range of construction applications where it is known as Incinerator Bottom Ash Aggregate (IBAA). It is essential, but challenging, to develop a circular economy for this fraction involving complete reuse because of the associated environmental and technical challenges. It contains high levels of contaminants including heavy metals (copper, lead, antimony, molybdenum etc.) and salts (i.e. Sodium sulphate and calcium chloride) that can leach into soil over time and contaminate groundwater if IBAA is not managed correctly. This project aims to develop a new method of treating IBAA particles. This will use a small amount of a special binding material for the granulation of the fine fraction of IBAA into a coarse material and change the soluble forms of contaminants into insoluble that can be beneficially used without leaching. The project objective is to investigate the feasibility of this novel approach to transform 100% of IBAA into a useful resource. We will aim to understand the mechanisms involved to ensure reliability. A further objective is to develop a lab-scale proof-of-concept for IBAA processing technology, to prove it readiness for pilot scale demonstration for industrial and real-world conditions. The treated IBAA material has potential to be used in roads construction and foundations, reducing the UK reliance on aggregate materials extracted from the environment. Incinerator bottom ash processing companies will benefit from being able to reuse all the ash they produce. The new technology will be patented and exploited globally, to provide a sustainable solution to the IBAA waste challenge.