Grease has been used in some form for centuries and continues to see new opportunities along with advancing performance and production techniques.
Take a look around the home or workplace and chances are grease is not too far away. The semi-solid lubricant is almost ubiquitous today, used to ensure the smooth operation of everything from windshield wipers and wind turbines to laptops, conveyor systems and door hinges. An estimated 80 percent of bearings are grease lubricated.
The latest edition of the Grease Production Survey Report published by the NationalLubricating GreaseInstitute points to a relatively stable market, with a 0.4 percent decrease in global production to 2.59 billion pounds for 2017 compared with the previous year.
Production has been pretty stable year on year, but there have been some changes in terms of geography and quality, said author of the report, Chuck Coe, a consultant with Grease Technology Solutions who also sits on the NLGI board of directors.
There is more demand for high-performing greases, which is driving up prices, and were also seeing increasing demand in Asia as these countries are becoming more industrialized. Its less expensive to make grease there than in North America or Europe, and there are more grassroots plants being built. Over the past six years, North American grease production has been on the decline, while Europe has seen some increases.
Grease consists of three core components: a base oil and additives held in place by a thickener structure.
Performance-enhancing additives increase the effectiveness of the grease, boosting properties such as oxidation and rust resistance, antiwear, water resistance, performance under extreme pressure and suitability at high temperatures.
The choice of thickener also affects how the grease performs and provides its unique consistency, with metallic soaps such as lithium, aluminum and calcium most commonly used. The addition of a complexing agent can further enhance the greases properties, boosting temperature resistance, for example. Lithium complex, calcium sulfonate and polyurea are seeing the most growth.
Lithium has been the thickener of choice for grease manufacturers for decades-a hugely versatile option with a dropping point of around 200 degrees Celsius, with lithium complex even higher at around 260 C. Lithium soap and lithium complex thickeners together represent over 70 percent of global grease production, with other thickener types taking a relatively smaller share.
Lithium is in high demand and is increasingly being diverted to battery production for use in mobile electronics such as cell phones and laptops. Some suggest its availability will tighten further, given the predicted upswing in the sale of electric vehicles in the coming years. This new generation of car requires long-lasting batteries using over 100 pounds of lithium, fueling supply concerns among grease manufacturers.
With lithium demand rising and output seeing little noticeable change, there is speculation that this may steer grease producers toward using alternative thickeners such as calcium sulfonate and polyurea.
Theres now a lot more demand for lithium coming from the battery industry, according to David Turner, NLGI board member and product specialist in the Fluid Technology Group at Citgo. There is more lithium production coming online, but to develop these additional resources takes time and investment. We could see the price of lithium go up significantly and that may be a big driver for a shift to a different type of thickener.
E-grease Opportunities
Fortunately, the e-mobility megatrend also poses plenty of opportunities for the grease market. Indeed, the prevalence of electric vehicles on roads could drive growth for the lubricant in years to come.
The past year has seen the headlines dominated with news of numerous countries pledging to ease environmental concerns by stopping production of internal combustion engines within the next few decades. Banning the sale of new gasoline and diesel vehicles should significantly alter how greases are used, with the new generation of vehicles requiring more specialized formulations.
The advent of the electric vehicle is going to have some influence on the grease market, said Coe. The volume of grease used should be similar to that of the internal combustion engine vehicle, but there will be a need for more sophisticated greases. They will need to have a long life and meet specific requirements in terms of conductivity and noise, for example.
I dont think there are going to be any major shocks moving forward, but there are plenty of opportunities with more specialized products, he added. Theres more demand for high performance, more load on the bearings and greater temperature extremes. Theres a continued push for technology development and innovation. I dont see total demand changing significantly, but the need for better, more niche greases is continuing to grow.
Process Evolution
Most manufacturers currently rely on batch manufacturing, which is often completed in a single jacketed kettle or a contactor reactor. The latter is more sophisticated and efficient, but both are tried and trusted methods for mixing, heating and cooling at high pressure to produce the finished grease. The continuous method is a faster alternative used by only a few manufacturers and is only viable if large yields are required.
United States-based Environmental Lubricants Manufacturing has pioneered another process to make biobased greases using microwaves. ELM says its patented technology means the cost of producing biobased greases are at parity with those using mineral oil. This segment remains comparatively small, and currently represents less than 1 percent of the overall market. There is plenty of room for potential growth, particularly given increasingly stringent regulation and environmental concerns.
I think the grease industry is going to see more of an evolution than a revolution, especially in terms of the processing, said Turner. With better process controls and less reliance on manual operation, we are finding better ways of producing grease. Modern plants are using automated controls to ensure the right temperature profiles or oil addition rates, and all the variables are becoming tightly controlled to get that consistency and make sure one batch is the same as another.
With the improvements in process controls, grease making is becoming more of a science than an art.
In this Spotlight, equipment maker ABB and grease producer Lanxess explain their latest developments and how they are shaping the future of grease.