Jacob Brinch-Nielsen, Vice President of Professional Services, FLSmidth Cement, brings together recommendations from experts across the flow sheet to demonstrate the role of upgrades in optimising the cement manufacturing process.
The Energy Challenge in Cement Manufacturing
Reducing energy consumption is a core goal for all cement producers, sitting alongside alternative fuels, reduced clinker content and carbon capture as one of the four pillars of decarbonisation. As we look to the future, when new emissions abatement technologies will skyrocket energy use once more, that goal becomes ever more important.
While automation and digitalisation have a critical role to play in optimising energy use, advances in mechanical equipment are often focused on reducing energy consumption – meaning there are many equipment upgrades that could help lower your energy bills, providing a relatively swift ROI in exchange for minimal disruption to your process. By optimising key process areas—grinding, dosing, preheating, and more—plants can reduce energy costs while improving operational performance. But where should they start?
Easy Upgrades to Optimise the Grinding Process
“One of the biggest sources of inefficiency in cement grinding is overgrinding,” explains Nick Litzenberger, Design Engineer. “Every extra pass through the mill consumes energy but does not necessarily improve product quality. This is especially critical in Type 1L cement, where fine limestone particles can lead to excessive power consumption and reduced throughput. Many cement plants still operate second- generation separators, which lack the precision of modern designs. Upgrading to a third-generation separator can optimise particle size distribution, lower energy use, and boost mill output.”
Third-generation separators for ball mills like the O-SEPA® or SEPAX™ utilise more hard-wearing materials, improving seal performance and separating more efficiently. These types of upgrades require just a 2 – 3-week shutdown, as much of the work can be done while the mill remains operational and deliver a 5 per cent to 10 per cent reduction in power consumption.
Among third-generation separators for VRMs, options like the ROKS-H separator specifically address overgrinding in Type 1L cement, delivering energy savings of about 2 – 3 per cent while improving product quality. Even an upgrade from an early 3rd generation separator, like a ROKS, to one of the latest separator designs, like a ROKS-H, can reduce power consumption and improve cement quality in a grinding circuit.
Reducing Energy Use in Feeding and Dosing
Even small inefficiencies in feeding and dosing can result in wasted energy and increased operational costs. If your dosing system struggles to maintain consistent feed rates, the inevitable result is instability in pyroprocessing and impacting power consumption.
“We’re continually exploring ways to reduce energy consumption in feeding and dosing applications,” says Peter Norek, Global Product Manager-Feeding and Dosing Technologies. “We’ve introduced digital features like Pfister® Smart Aeration, which reduces compressed air usage by up to 90 per cent, patented FEEDFlex™ technology, which enables much lower fossil fuel dosing, and the FDC controller upgrade, which includes a new motor, enhancing efficiency and reducing electricity consumption. These are all simple upgrades with a positive environmental impact.”
Part 1 of 3. Read parts 2 and 3 in the June and July issues of Indian Cement Review
(Communication by the management of the company)
