Horizontal Spinden Reactor

DESCRIPTION

The Spinden reactor was conceived and developed by Mr. John Sinden of JSA, a process engineer with over 45 years of experience working in various aspects of the fertilizer industry. CASTech is a licensed manufacturer of the Spinden reactor. The Spinden reactor is a horizontal paddle mixer designed for the continuous mixing and granulation of slurry with reactive acids; for example, a limestone slurry is mixed with a solution of liquid phosphoric acid and water to form granulated MDCP. The liquid reagents are dispersed into the reactor’s reaction chamber via a cyclonic pre-reactor. The configuration and orientation of the blades on the reactor shaft ensure that the two reagents are mixed uniformly to achieve a complete reaction. The distance between the tips of the blades and the Spinden wall is adjusted to work with the material properties to ensure effective granulation of the product. The shaft rotation speed can be controlled by a frequency inverter on the drive motor to precisely control the size of the granules produced. The faster the reactor rotates, the smaller the granules.

Exclusive to CASTech reactors, the walls of the Spinden horizontal reactor are made of chlorobutyl rubber, while competitors use stainless steel for the walls of the chutes. Flexible rubber is resistant to acid corrosion and also resistant to the wear of the paste mixture. This is important, but the flexibility of rubber is even more relevant to the granulation process. The flexing of the rubber maintains constant pressure as the paddles pass through the slurry and the mixture is pressed against the walls. This results in more uniform bead size, even with wear on the paddles. As material accumulates inside the reactor walls, the passage of the blades causes the chute wall to flex further until the material releases and is ground back into the mixture slurry. This self-cleaning aspect of the flexible rubber gutter does not happen with rigid material gutters. This results in reduced maintenance time and also the amount of granules above the desired size. The flexibility of the walls also means a reduction in wear on the blades and extends the life of the machinery.

All machinery parts are designed to industry standard. The Spinden shaft is directly driven by a single-stage, helical gear reducer. A variable speed drive provides smooth system start-up as well as precise control of material flow through the reactor by controlling the speed of rotation of the blades. Any metal exposed to the acid mixture is made of stainless steel. Teflon sealing seals protect against leakage around the shaft on both sides of the reaction chamber. The drive system, speed reducer and couplings are all selected and assembled so that some of the work can be done without having to disassemble adjacent components.

John Sinden/Castech Spinden reactors are available in varied capacities. Make a consultancy.