‘Breakthrough’ PFA replacement tipped to help decarbonise UK cement production

L to R: Zero Waste Scotland built environment manager, Stephen Boyle; Built Environment – Smarter Transformation’s (BE-ST) head of sustainability programme, Jennifer Smart; and Innovative Ash Solutions director, Robert Green.

LANARKSHIRE-based Innovative Ash Solutions (IAS) has launched a new environmentally-friendly replacement for pulverised fly ash (PFA) which it said is a ‘key but increasingly scarce’ ingredient in cement production.

IAS – a 50/50 joint venture between Levenseat and Organic Innovative Solutions Limited –  has developed a new process, which transforms air pollution control residues from municipal and wood biomass incinerators, to create its new PFA replacement – the first to be given end of waste accreditation by the Scottish Environment Protection Agency (SEPA).

According to the UK trade body Minerals Products Association, around 15 million tonnes of cementitious materials – which includes cement, concrete and grout – are manufactured in the UK each year. The closure of UK based coal fired power stations has resulted in a reduction in the availability of PFA, with an increased reliance on imports, rising from 76,000 tonnes in 2012 to 325,000 tonnes in 2019.

IAS said the new ‘breakthrough’ PFA replacement, produced in Scotland, reduces this increasing reliance on imports and provides a lower carbon solution, enabling a more circular and sustainable approach to cement production.

With its new end of waste status, the PFA replacement can be marketed for use as a supplementary cementitious material (SCM) in the production of CEMII, the most common form of bagged cement used for general construction purposes. It can also be used in a variety of other applications including mortar, render, screed, and grout.

Over the next five years, IAS said it intends to build three full scale industrial plants, and has been granted planning permission for the first of these. Initially the plant will produce up to 54,000 tonnes of PFA replacement annually. The company estimates it can ultimately produce up to 500,000 tonnes of its product from UK-produced air pollution control residues

Last year Levenseat launched a new stream of accredited low carbon aggregates products which provide a more sustainable and lower cost alternative to virgin aggregates used by the construction sector. These products were the first from any Scottish company to secure end-of-waste status from SEPA.

Innovative Ash Solutions director, Robert Green, said, “We are excited to bring this new product to market. Innovative Ash Solutions are the first and, so far, the only company in the UK to have achieved ‘end of waste’ accreditation for a PFA replacement for this type of use. Our research shows there is potential to produce more than 500,000 tonnes of PFA replacement from UK air pollution control residues every year which would reduce the need for importing materials and support the decarbonisation of cement and concrete products.”

Zero Waste Scotland built environment manager, Stephen Boyle, added, “A circular approach to closing the loop, and therefore keeping resources in use for longer, is necessary to help reduce carbon emissions from the construction industry and to help reach the Scottish Government’s ambitious target to become a Net-zero emissions society by 2045.  We are pleased to have supported IAS in the development of this innovative PFA replacement, which utilises existing waste streams to keep resources in use for longer.”

Built Environment – Smarter Transformation (BE-ST) head of sustainability programme, Jennifer Smart, commented, “We welcome the development of this new PFA replacement and the opportunities it provides in supporting the construction sector on its net-zero journey.”

Andrew Sullivan, of SEPA’s National Waste Unit, said, “SEPA supports new circular approaches which maintain a high level of environmental protection. IAS has developed a new solution for air pollution control residues, creating a pulverised fuel ash replacement for CEMII cement. By achieving ‘end-of-waste’ status, they can produce a recycled product which is no longer subject to waste controls and help reduce the carbon impact of cement use.”