Scrap Gel Caps

March 9, 2012
 

Pharmavite is a very large nutraceutical firm whose products are marketed under the Nature Made trade name.  Owned by Otsuka Pharmaceutical in Japan, Pharmavite has its manufacturing operations in San Fernando, California.

Pharmavite uses a Vincent screw press in an unusual application.  The press recovers the valuable pharmaceutical contents from scrap gel capsules.  They refer to our press as the reclaim machine.

Scrap gel caps fall in two main categories: (1) Brittle ones due to over-drying; these are easy to break and drain.  And, (2) normal gummy ones which have been rejected due to failing an assay test. 

Since the contents of the gel caps are being recovered, the machine must be fully sanitized between each batch of gel caps.  During the testing period an evaluation was made between a passivated glass bead finish and having the machine electro-polished.  Vincent had never had one of our presses electro-polished, but now we have found a local source in the Tampa area.

Pharmavite's goal is to recover 85% of the fluid in the gel caps.  All of them have an oil based liquid inside, so they have a long shelf life without the need for refrigeration.  They are stored in mini-bulk bags, on pallets.  The bags containing scrap are red-tagged.

A switch from bovine gel caps to porcine gel caps was made because of mad cow disease.  Now there is a push to go on to pectin (i.e., plant, not animal) gel caps.

Vincent's screw presses came to Pharmavite's attention through our sales rep, Jeff Rubak, SPM Sales Inc.  Jeff's 's main line is Quadro.  The Quadro's are emulsifiers which are used to blend pharmaceutical powders into oil before being injected into the gel caps.

The press used in this application is a Model CP-6.  It has an unusual feature in the Series CP machines, a rotating cone.  This was found to be indispensable for satisfactory operation.  Also, a sixth pair of resistor teeth was added to serve as spin-stops.  High discharge cone pressures are required to break the capsules, along with a tight fit between the cone and the cake discharge spout.  Half pitch flighting in the inlet hopper, along with a high speed gearbox, provide the best possible feeding into the press.

 

From 50 to 200 kilos per hour of gel caps are pressed.  Recovery ranges from 75% to as much as 97% of the pharmaceutical content of these gel caps.  Reduced screw rpm and throughput have been employed in order to get higher liquid recovery.

A nitrogen purge feature was added to the press because some gel caps use fish oil.  This might tend to spoil if exposed to oxygen.  Vincent supplied covers fitted with edge seals for this purpose.

 

Issue 243