Apparatus and method for metering, mixing and packaging solid particulate material

Method for producing solid particulate material from solid particulate components, which comprises the following:

• a) sequentially feeding at least two components of solid particulate materials to a metering unit;
• b) sequentially metering each of said component in said metering unit according to a predetermined recipe;
• c) transferring said components simultaneously into a mixing unit by effect of gravity;
• d) mixing said components in said mixing unit to form a particulate material fulfilling said predetermined recipe;
• e) discharging said particulate material from said mixing unit, simultaneously metering a predetermined amount of said particulate material and transferring said metered amount into a container located downstream said mixing;
• said mixing d) and said discharging e) are carried out by rotating a mixing tool in said mixing unit, said discharging being achieved by the combined action of gravity and rotation of said mixing tool at a peripheral speed higher than 30 m/min.

Apparatus for producing solid particulate material, comprising storage tanks for separately storing at least two different components of a solid particulate material, and further comprising:

• a) a metering unit for said components of a solid particulate material;
• b) a mixer comprising a stationary casing provided with a rotating mixing tool, wherein said stationary casing of said mixer comprises an upper loading port and said mixing tool is mounted on a rotating horizontal shaft actuated by driving means located outside said casing, wherein:
• said casing comprises two frusto-conical walls joined at their bases and disposed with their axis aligned horizontally, said shaft being mounted horizontally along said axis of said frusto-conical walls;
• said mixing tool comprises a plurality of spokes mounted on the centre of the portion of said shaft contained within said casing, each of said spokes being provided with a blade in the proximity of, but out of contact with, said frusto-conical walls;
• said casing being provided with a discharge port associated to a discharge valve mounted on the bottom of said casing
• c) a discharge valve mounted on the bottom of said mixer;
• and
• d) a metering and packaging unit located downstream said mixer.