A device and apparatus for mixing and dispersing a solid and a liquid are provided. The device includes a powder pulverizing mechanism fixedly connected to a main shaft. The powder pulverizing mechanism is located in a powder feed chamber. The powder feed chamber is provided with a powder feed port. A liquid feed chamber is arranged on an outer side of the powder feed chamber. The liquid feed chamber is provided with a liquid feed port, and the liquid feed chamber is provided therein with a dispersing mechanism fixedly connected to the main shaft. A lower portion of the liquid feed chamber and a lower portion of the powder feed chamber are separately in communication with an upper portion of a mixing chamber. The mixing chamber is provided therein with an impeller fixedly connected to the main shaft.

A compact and transportable equipment adapted to be used for hydraulic fracturing operations on gas or oil fields includes a means for unloading powder polymer, a means for supplying a polymer powder to a silo, and a silo for storing polymer in powder form, the silo having inside a vertical screw located in a vertical pipe, the lower end of the shaft of the vertical screw extending outside of the silo. The equipment has a feed hopper of a polymer metering device, a device for metering out the powder polymer, at least one tank for hydrating and dissolving the dispersed polymer originating from the dispersing and grinding device, and at least one volumetric pump enabling injection and metering of the polymer solution. The lower end of the shaft of the vertical screw has a rotating ring, the rotating ring being perpendicularly fixed on the shaft and being equipped with at least three straight paddles, positioned perpendicularly to the horizontal plan of the ring.

Additive manufacturing apparatus and methods for mixing and dispensing materials, and articles with controlled particle concentrations. Additive manufacturing apparatus includes a mixer; a reservoir in fluidic communication with the mixer; and a build plate parallel to the reservoir. Additive manufacturing apparatus includes a mixer and a solid particle dispensing system and/or a slurry dispensing system. A method for handling precursors during additive manufacturing includes (a) providing first and second precursor materials and/or a slurry to a mixer; (b) mixing the materials in the mixer; (c) transporting the mixed materials directly to a reservoir disposed in parallel with a build plate; (d) curing at least a portion of the transported and mixed materials; and (e) repeating step (d) at least once. An article includes a plurality of adjacent layers, a concentration of particles in each layer defining a controlled concentration gradient and/or vary by no more than 50%.