Agglomerating and drying apparatus

A agglomeration system for forming granules from powder, comprising:

• (a) an agglomerator for forming wet granules from a mixture of powder and liquid;
• (b) a carrier gas source coupled to the agglomerator for suspending the wet granules in a fluidized stream;
• and
• (c) a dryer having an inlet for receiving the fluidized stream and an outlet for discharging dry granules, and defining an elongate duct extending from the inlet to the outlet, the elongate duct defining a cross-sectional area that increases in size in proportion to a distance from the inlet.

An apparatus for drying granular material, the apparatus comprising:

• an elongate drying tower having an outer wall having a top portion and a bottom portion;
• a material inlet in the top portion of the drying tower for a fluidized stream of granules including the granules and a carrier gas;
• the bottom portion of the drying tower defining a collection chamber for the granules and having an outlet for discharging the granules from the collection chamber;
• a central, tubular gas exhaust duct extending within the drying tower to convey the carrier gas from the collection chamber to a gas exhaust in the top portion of the drying tower;
• a pump coupled to one of the inlet or outlet for inducing a differential pressure therebetween;
• and
• a continuous guide strip extending in a spiral between the drying tower outer wall and the central exhaust duct along a length of the top portion of the drying tower, to define a spiral path for conveying the fluidized stream of granules from the material inlet to the collection chamber, the pitch of the spiral increasing from the material inlet to an outlet of the spiral path from which the granules are discharged into the collection chamber.

An agglomerator apparatus comprising:

• a rotary blade assembly the rotary blade assembly including a plurality of blades arranged in a circumferential array around a central hub, the blades rotatable about the hub in a rotary plane, each blade having a radially outer end portion with a cutting edge facing the direction of rotation;
• a mesh screen circumferentially surrounding the rotary blade assembly, the mesh screen having a mesh size selected to allow particles of a predetermined size or smaller to pass from the rotary blade assembly through the mesh screen;
• and
• a manifold surrounding the mesh screen for collecting particles which have passed from the rotary blade assembly through the mesh screen, the manifold directing the particles to a material outlet from the agglomerator.

A method of preparing granules, the method comprising, in sequence, the steps of:

• mixing particulate material and a liquid to form a mixture;
• feeding the mixture into the center of a rotary blade assembly;
• inducing the wet mixture to flow radially outward through the rotary blade assembly, whereby the rotary blades cut the mixture into granules;
• and
• screening the cut granules through an annular screen coaxially surrounding the rotary blade assembly.