Hosokawa Alpine is presenting two technological solutions for fine grinding of various types of rubber at the expo. The main objective of these processes is to ensure energy efficiency and a sustainable, economic production of fine rubber powders.
One of the processes – the cryogenic grinding process – involves cooling the material with liquid nitrogen, which makes it easier to process the particles.
“The starting material is cooled down to a glass transition temperature with liquid nitrogen to obtain particularly high particle sizes with consistent quality, even when micronizing soft or flexible materials,” explained Thomas Weischer, operations director of recycling and granulators division, and Robert Patalweski, senior sales manager for recycling and granulators division.
In comparison, the second process, known as ambient grinding, sees the ground material get shredded using pressure and shear stress. The Hosokawa Alpine rubber powder mill (RP) is used to grind and classify the material.
With the combination of the specially developed Hosokawa Alpine Contraplex CW II pin mill and the Stratoplex ASP II classifier, the company says that the levels of pulverulence are guaranteed.
“The counter-rotating operation of the two pin discs makes it possible to achieve relative speeds of up to 250m/s and a throughput of up to 1400kg/h. Fineness levels between 125μm (120 mesh) and 425μm (40 mesh) can be easily reached, whereby the fineness of the end product varies according to the speed of the pin discs,” said Robert Patalewski, senior sales manager at Hosokawa Alpine.
Both processes, whether cold or ambient, have their advantages for production of very fine rubber powders. In a cryogenic process, the individual particles are more cubic and have a smooth surface with sharp corners and edges. The fine powder from ambient grinding is characterized by an extremely high surface area.
“Since an even finer grinding of rubber granulate is sometimes needed but not possible economically, it is necessary to classify a finer product with cryogenic grinding. For these kinds of applications, the Stratoplex ASP II classifier has proven to be the ideal machine in terms of efficiency and investment costs,” added Patalewski.
Hosokawa Alpine was previously a visitor at Tire Technology Expo and after positive discussions with other attendees, the company chose to become an exhibitor at this year’s show.
You can visit Hosokawa Alpine at Booth 9026.
