After more than 75 years in business and hundreds of installations worldwide, we still get excited when we demonstrate Lancaster Mixers ability for homogenous powder mixing and granulating  in a single batch operation.  With an average batch runtime under ten minutes for most applications, Lancaster Mixers ability to granulate produces high on size yields in a repeatable and predictable process.     These “one-step mix-granulate” processes are utilized across a wide variety of applications including the production of fertilizer, technical ceramics, lightweight aggregates, beneficial re-use of waste, and more.

A typical Mix-Pelletizing Cycle looks like this:

  1. Feed dry ingredients into mixer from weigh hopper(s)
  2. Dry mix and de-lump
    1. The de-lumping capability means the raw material does not have to be dry
  3. Add liquid or binder from separate weigh hopper(s)
  4. Wet mix and pellet formation
    1. Dusting (optional – to stop pellet growth and clumping)
  5. Discharge

So, how is a mixer able to granulate powder?   First, the rotor agitates the mix while the counter-current rotation of the pan itself quickly creates a homogenous mix of wet and dry ingredients inside the pan.  Continued mixing at high intensities for time pre-determined from lab testing imparts highly intense energy to the mixture resulting in rapid homogenization.  The shearing forces created by the counter rotating pan and rotor creates a standing wave like action in the mixing pan.   As the particles tumble they agglomerate similar to rolling snowball, until specifications for size and shape are met.  The pellets are then completely discharged through the bottom of the mixer so a new batch of ingredients can be fed through the top for another run.  By controlling the variables for ingredients, time and tooling speed, the Lancaster Mixer can produce consistent repeatable results batch after batch.

Each step is programmed and controlled by PLC, requires very little operator attention, and produces consistent product properties batch after batch.  A number of factors can be adjusted to influence granule/pellet characteristics including rotor design, rotor speed, direction and granulation time, and pan speed.  Additionally, optimization of raw materials such as powder size, binder type, and dry:liquid ingredient ratio can enhance pellet properties.

Our technical staff has extensive experience testing a wide range of materials that have been commissioned over the years, so we can guide proof of concept testing using a smaller lab-scale mixer on-site at Lancaster Products. .  Recipes established during lab testing can be scaled up for production volumes and are optimized when machinery is installed.

Contact us to schedule a visit to our test lab where you can see the mix-pelletize process at work with your own materials.