Horizontal Spinden Reactor

The Spinden was invented and developed by Mr. John Sinden of JSA, a Process Engineer with more than 45 years of experience working in various aspects of the fertilizer industry.   J&H is a licensed manufacturer of the Spinden Reactor.  The J&H Spinden Reactor is a horizontal paddle mixer designed for continuous mixing and granulation of a slurry with a reactant acid, for example a limestone slurry being mixed with liquid phosphoric acid and water solution to form granulated MDCP.  The liquid reactants are sprayed into the Horizontal Spinden’s reactor chamber by a cyclonic Pre-Reactor.  The configuration and orientation of the paddles on the Spinden shaft insure that the two reactants are uniformly blended for a complete product reaction.  The distance from the end of the paddle blades to the wall of the Spinden are regulated to work with the properties of the material to efficiently granulate the product.  The speed of rotation of the Spinden shaft can be controlled through a variable frequency drive on the drive motor to accurately control the size of granules produced.  The faster the Spinden rotates, the smaller the granules.

Unique to J&H Spinden reactors, the walls of the horizontal Spinden Reactor are fabricated from chlorobutyl rubber or rubber belting material where our competitors use solid stainless steel for the walls of the trough.  The flexible rubber is resistant to corrosion from the acid and also from the wear of the slurry mixture.  This is important, but the flexibility of the rubber plays an even more important function of helping the granulation process.  The flexing of the rubber maintains a constant pressure as the paddle blade passes through the slurry mixture and the mixture is compressed against the walls.  This results in more uniform granule size, even as the ends of the paddles wear.  And as material builds up on the interior walls of the reactor, the passing of the paddles will cause the walls of the trough to flex more and more until the material breaks loose and is ground back into the slurry mixture.  This self cleaning aspect of the flexible rubber trough walls will not happen with rigid metal troughs.  This significantly reduces maintenance time in cleaning conventional horizontal reactors and reduces the amount of oversized, and clumped material introduced into the products at the reactor discharge.  The flexing of the walls of the trough and the self-cleaning mechanism also significantly reduces wear on the paddle blades and extends the overall working life of the machine.

All parts of the machine are designed to industrial standards.  The spinden shaft is direct driven through a helical gear, single-stage, speed reducer. A variable speed drive for the motor provided by the customer provides a soft-start for the system as well as precise control of the material flow through the reactor by controlling the turning speed of the paddles.  Any metal exposed to the acidic mixture is made from corrosion resistant stainless steel.  Packing gland shaft seals packed with square Teflon cord packing provide leakage protection around the shaft at both ends of the reaction chamber.  The drive system, speed reducer, and couplings are all selected and mounted so that any part can be work on without having to disassembly any adjacent components.  J&H stands behind the innovative concept, design, and manufacture of this new product in the J&H product line.

See J&H Horizontal Spinden Reactor brochure or return to J&H Mixer/Granulators main page.