An externally mounted tank nozzle assembly which can be used in many mixing systems. The assembly can be installed as a fixed nozzle or as an externally adjustable nozzle. The disclosed nozzle is light-weight, corrosion-resistant as well as abrasion-resistant to withstand many tank mixing environments and conditions.

Disclosed herein are powder mixing apparatuses and methods that utilize the deagglomerizing and mixing effects of an air flow that impacts a flowing powder. The resulting powder can have smaller particle sizes and/or exhibit a more homogenous mixture than the premixed powder.

Some variations provide a system for producing a functionalized powder, comprising: an agitated pressure vessel; first particles and second particles contained within the agitated pressure vessel; a fluid contained within the agitated pressure vessel; an exhaust line for releasing the fluid from the agitated pressure vessel; and a means for recovering a functionalized powder containing the second particles disposed onto surfaces of the first particles. A preferred fluid is carbon dioxide in liquefied or supercritical form. The carbon dioxide may be initially loaded into the pressure vessel as solid carbon dioxide. The pressure vessel may be batch or continuous and is operated under reaction conditions to functionalize the first particles with the second particles, thereby producing a functionalized powder, such as nanofunctionalized metal particles in which nanoparticles act as grain refiners for a component ultimately produced from the nanofunctionalized metal particles. Methods for making the functionalized powder are also disclosed.

A multiple submergence depth diffused air system includes: a vessel having a non-flat bottom floor and fluid; a single blower or compressor that provides a single mass flow and a single pressure discharge of air; a plurality of air distribution lines that extend from the single blower or compressor into the fluid, in which outlets of the plurality of air distribution lines have grids with air diffuser units for distributing air; and orifice plates associated with each air distribution line. At least some of the air distribution lines extend to different depths within the fluid and at least one of the air distribution lines extend into the fluid formed in the non-flat bottom floor of the vessel. The orifice plates can also be sized and configured to produce a unique pressure head for each air distribution line at a designated mass flow of air to the respective air distribution line.