Oliver Dietrich

Application Technology

Manager Application Technology Industry

+49 2151 7811-226

+49 2151 7811-503

oliver.dietrich@messergroup.com

Fine grinding using cryogenic grinding technology

Fine powders with a big impact

Cold grinding technology reduces production costs and simultaneously increases product quality.

During cold grinding the materials to be ground are cooled and embrittled with cryogenic liquid nitrogen or carbon dioxide. Cooling of heat sensitive materials with cryogenic gases during the grinding process prevents their temperature from rising through the heat released during the grinding process. This eliminates material melting and sticking.

With the right grinding technique this also allows for finer products of a better quality and a significantly higher throughput than with classical grinding processes; even with tough and elastic products such as thermoplastics and elastomers. Materials with a low softening point (hot melt adhesive, bitumen) can be equally well ground. In the case of spices, high grinding temperatures lead to loss of aroma and flavour; mill cooling means that the product is treated gently and a significantly higher share of the essential oils are conserved. In the case of other food stuffs, vitamins and proteins are retained.

Products with a high oil or fat content (nutmeg, oilseed, meat meal) can quickly cause blockages in the grinding tools and chamber. Cooling with cryogenic gases keeps the product free-flowing so that it leaves the mill without clogging it.

This means, due to the cold grinding technology production costs will be reduced while increasing the product quality.

Cryogenic composite material separation

Different materials have different coefficients of linear thermal expansion and embrittlement capabilities; cold grinding technology utilises this to separate composite materials (fibre reinforced thermoplastics, galvanised plastic parts, old tyres etc.) into their component parts or from their accompanying substances.

Inertisation of mills

Nitrogen or carbon dioxide displaces  oxygen to create an inert atmosphere which protects against fire or explosion. The milling of combustible products and those having a dust explosion risk is made significantly safer.

We are happy to provide you with background information, benchmark data and a list of suppliers for mills, spare parts and products related to cold grinding. You may contact our specialists directly and  arrange trials for your product.

Complete cryogenic solutions

The Messer Group offers complete solutions from one source:

Advice on purchasing the right type of mill and the supply of cold grinding equipment such as paddle screw coolers and cryogenic control valve units; provision of the tank for delivery of cryogenic gases; supply contracts; commissioning, plant support and supply of spare parts.

Furthermore, Messer develops and supports tailor-made cryogenic grinding processes for the manufacture of fine powders (< 500 ┬Ám), such as plants for the manufacture of fine rubber powders, hot melt manufacture, powder manufacture from thermoplastics, soft PVC recycling, spice mills, oilseed grinding, mill inerting; and many more special developments.

Consultation and grinding trials

Sample manufacture and interpretation of results

The Messer Group operates a highly specialised technology centre which offers you the opportunity to benefit from process developments, estimate production costs or manufacture sample batches. An example of this is the professional grinding of samples using liquid nitrogen, with all grinding parameters, including throughput, power and nitrogen demand as well as particle size distribution being measured, evaluated and made available to the customer.

The construction of the trial plant serves as an ideal reference as it complies to the conditions in an actual production plant. For this reason, the results obtained here are of particular interest as they can be applied to large scale production. In addition to the manufacture of grinding samples, manufacturing costs can be estimated under different production conditions and compared with other grinding processes.

Exisiting mills can also be optimised

Granulate coolers, nitrogen control valves and temperature controls can be provided for carrying out on-site trials.

Contact us to arrange a consultation meeting or possible material trials in our pilot plant. Give us a call or fill out the contact form.