Many cement plants today are bound by sustainability targets set by the World Business Council for Sustainable Development, under the voluntary Cement Sustainability Initiative. Globally, the cement industry has reduced its specific net CO2 emissions per t of product by 17% since 1990 – from 756 kg/t to 629 kg/t in 2010. The Cement Sustainability Initiative Roadmap of 2009 suggests that the target for 2050 should be 420 kg/t. Significant progress in this direction has been made by using strategies such as the improvement of thermal and electric efficiency, alternative fuel use, clinker substitution and carbon capture and storage. These methods often call for substantial investments.
This is where modern speciality lubricants come into play as a way to achieve the sustainability objective of improving the CO2 balance without jeopardising major investments and, at the same time, helping to attain operational excellence. Lubricants can help improve sustainability, as well as production efficiency, in all major processes of cement production – a systematic and dedicated approach is necessary to achieve these objectives. Some simple yet effective strategies are listed below.
Reducing the quantity of lubricant in open gears
Most open gears used today have a total loss lubrication system. For a conventional open gear lubricant based on graphite, lubricant consumption is in the range of 4.5 to 6 tpy. This is typical of an open gear drive with a flank width of 700 mm. By changing over to transparent speciality lubricants designed for open gears, consumption can be reduced to 1.8 to 2 tpy.
Transparent open gear lubricants are free from graphite and have a special composition. The special ingredients in the lubricant form reaction layers on the surface of the tooth flanks and prevent damage such as pitting, scuffing and wear. Field trials have proven that the protection offered by the reaction layer against wear, even under shock loads, is better than with graphite-based lubricants. Temperature across tooth flanks and vibration levels also shows significant improvement, thus improving productivity and energy efficiency.
Switching from mineral oil-based lubricants to bio-lubricants
Common industrial greases or oils contain around 80 – 95% base oil. These base oils are usually derived from petroleum-based products. In bio-lubricants, these base oils are derived from plant sources, thus considerably reducing the impact on the environment. Innovative lubricant manufacturers have developed cost-effective bio-lubricants.
Lubricants used for open gear drives can have a significant impact on sustainability. By replacing existing graphite-based products with a bio-lubricant, consumption can be reduced significantly. Since the base oil is derived from 100% renewable resources, it is environmentally friendly. This makes it safe during handling and easy to dispose of. Klüber Lubrication has developed the Klübersustain series of products, the performance of which is at least comparable to existing mineral oil-based products while also being cost-effective, hence helping to achieve operational excellence, as well as environmental sustainability.
This is part one of a two-part article written for World Cement’s March issue and abridged for the website. Subscribers can read the full issue by signing in, and can also catch up on-the-go via our new app for Apple and Android. Non-subscribers can access a preview of the December 2015 issue here.
Read the article online at: https://www.worldcement.com/special-reports/02032016/using-specialty-lubricants-cement-plants-part-one/