Crum Making from Scrap Tires

Making Crumb/Crum rubber from tires

Now, I guess its time to discuss making crumb rubber from the Rasper. This is done in a granulator rasper or a crackermill. There are only two ways to do this.

Use a granulator Rasper, or use a Crackermill.

Granulators for crumb rubber production

This is the beginning of a crumb system

This design takes a granulator Rasper and makes an 8 mesh material.

You need about 100 hp for every ton of crumb produced per hour from a 5mm granule to an 8 mm granule in a granulator Rasper.

This is the stage where fiber liberation occurs.

Total fiber liberation occurs at 10 to 20 mesh

crumb rubber screening system

This is the screening system after the granulator Raspers that allows for fluff removal and also proper sizing of materials produced in the system. This is not a back yard design, it’s an engineered system.

The importance of this crumb rubber design is that you are now involved in an explosive environment

Fiber explodes

Fine rubber dust explodes

Dust containment and fiber containment is critical or your plant will explode!

air filtration system for crumb rubber production

The air systems for this crumb section are very extensive and complex. There are many sections of the crumb system that involve cleaning of the crumb from dust and dirt and fluff and contamination.

If the crumb is not clean or has high moisture content it can’t be sold or used. If the crumb has any metal contamination it can’t be sold. If the crumb has any fiber contamination it can’t be sold.

So, if you want to make crumb, you have to make it right.

Crumb rubber size separation with air system

The use of a granulator Rasper or a Crackermill is not the issue at this point in the design…

The issue in the design of a crumb system is proper screening and proper cleaning and separation of contamination from the crumb rubber.

The term crumb refers to fine rubber sized products. Crumb sizing is determined by the number of screening holes per square inch. So 25 mesh rubber crumb, as an example, would be screened using 25 holes per square inch. So 25 mesh rubber crumb is about 1/25ft of an inch of vulcanizes tire rubber.

complete air system for crumb rubber production

If your cleaning system does not look like this, you don’t have a cleaning system for crumb as this is a basic waffle system, secondary magnet system, fluff removal and dust removal system with air knife cleaning

If you want to discuss this further please contact our group for more information and a consultancy.