Cement production can be divided into the two basic steps of clinker production and grinding. Clinker is made in a rotary kiln using fossil and non-fossil fuels to heat raw materials to 1,450°C, the clinker is cooled and then ground with other materials to produce cement powder. The combustion of the fossil fuels and indirect emissions from electricity consumption in cement production accounted for a UK sector carbon footprint of 7.5 million tonnes in 2012 (data sources include CCA data, EU ETS and NAEI)
The UK Governments Industrial Decarbonisation and Energy Efficiency Roadmap to 2050 for the Cement Industry published in March 2015 reports. There are opportunities to increase heat recovery in the cement sector, both to improve energy efficiency and to produce electric power. Heatcatcher has studied the technical feasibility of recovering waste heat to generate electricity from the UK cement plants, concluding 30.0 MWe of low carbon generating capacity is available to reduce grid demand for electricity and associated carbon footprint of 100,000 Tonnes of CO2 per year.
Waste heat recovery to power is standard practice in China and examples of operation in Europe, include the 4.0 MW power generation ORC plant commissioned in 2012 at the Holcim plant in Alesd, Romania, the 5.0 MW power generation ORC plant commissioned in 2013 at the Holcim plant in Slovakia and the 6.8 MW power steam generation plant in 2012 at the Rohrdorfer plant in Germany.
The Industrial Decarbonisation Roadmap 2050 report recognises that technological and economic support is required for Heat Recovery technologies to be rolled out across eight heat intensive industries including the cement sector. The Department of Energy & Climate Change (DECC) is now in phase 2 of determining what techno-economic support actions are required for UK companies to adopt Heat Recovery technologies improving their electrical efficiency, cost competitiveness whilst meetingÂ decarbonisation targets. The DECC Action Plan for incentives will be published in Decemeber 2016.