The company plans to switch to dry waste material such as rubber from used tyres and plastic to heat the kiln at the Castlemungret plant which employs 80 on the outskirts of the city.
The switch will cut costs, make the plant cleaner and more competitive, according to the company.
A spokesman for Irish Cement said they will shortly be lodging a planning application with Limerick City and County Council for the replacement of fossil fuel with alternative fuels and raw materials to improve the sustainability of their operations.
The company will also be seeking a revision of its licence from the Environmental Protection Agency.
“Limerick is Ireland’s oldest cement plant, having commenced operations 77 years ago.
"Its continuous operation has been sustained by continuous investment in new technologies and processes.
"After the recent period of reduced demand, production is once again on the increase at home and abroad for cement.
"This fuel replacement programme will be key to sustaining this growth,” said Castlemungret plant manager, Pat Robinson.
“Based on exerience in other cement plants in Ireland and throughout Europe, the opportunity to reduce our dependence on imported fossil fuels will prove critical to our ability to operate competitively and sustain jobs at Irish Cement Limerick into the future.”
Councillors from the Limerick City West metropolitan district were briefed on the plan earlier this week when they met senior executives from the company.
In making cement, the kiln has to be heated to over 1,400 degrees, higher than the 1,100 degrees a volcano reaches.
Thousands of tons of used tyres will be ferried to the plant along with shredded plastics which waste disposal companies cannot process.
Used tyres now piling up around the country pose a major problem with regards to their proper disposal.
The making of cement involves the mixing of materials including limestone, slate, ore, ash and heating them to nearly 1,500 degrees.
The ash used at the Limerick cement plant is brought from the ESB Money Point Power station in west Clare.