High thermal transfer, hollow core extrusion screws (50, 52, 124, 126, 190) include elongated hollow core shafts (54, 128, 130, 192) equipped with helical fighting (56, 132, 134, 194) along the lengths thereof. The fighting (132, 134, 194) may also be of hollow construction which communicates with the hollow core shafts (54, 128, 130, 192). Structure (88, 90) is provided for delivery of heat exchange media (e.g., steam) into the hollow core shafts (54, 128, 130, 192) and the hollow fighting (132, 134, 194). The fighting (56, 132, 134, 194) also includes a forward, reverse pitch section (64, 162, 216). The extrusion screws (50, 52, 124, 126, 190) are designed to be used as complemental pairs as a part of twin screw processing devices (20), and are designed to impart high levels of thermal energy into materials being processed in the devices (20), without adding additional moisture.

Apparatus and methods for food production including a food preconditioner (228) operable to heat and partially pre-cook food ingredients, and a twin screw extruder (20) operable to further cook the preconditioned ingredients to create final food products. The extruder (20) includes a pair of hollow core extrusion screws (50, 52, 124, 126, 190) having elongated hollow core shafts (54, 128, 130, 192) equipped with helical fighting (56, 132, 134, 194) along the lengths thereof. The fighting (132, 134, 194) is also of hollow construction which communicates with the hollow core shafts (54, 128, 130, 192). The flighting (56, 132, 134, 194) also includes forward, reverse pitch sections (64, 162, 216). The extrusion screws (50, 52, 124, 126, 190) are designed to impart high levels of thermal energy into materials being processed in the extruders (20), without adding additional moisture.

A method is described of mixing fluid materials, including solids and gases. The materials to be mixed are introduced between two cylindrical rotors mounted in parallel on a motorized shaft. The rotors have arrays of cavities on their cylindrical surfaces and rotate within close proximity to the interior of a cylindrical shell. Passage of the fluid between the rotating rotors and the interior surface of the cylindrical shell causes cavitation, which mixes the materials. The mixture is passed to outlets on the far sides of the rotors from the inlet. Apparatus is described for extending the flow path of the materials and thus increasing exposure to the cavitation process.

High thermal transfer, hollow core extrusion screws (50, 52, 124, 126, 190) include elongated hollow core shafts (54, 128, 130, 192) equipped with helical fighting (56, 132, 134, 194) along the lengths thereof. The fighting (132, 134, 194) may also be of hollow construction which communicates with the hollow core shafts (54, 128, 130, 192). Structure (88, 90) is provided for delivery of heat exchange media (e.g., steam) into the hollow core shafts (54, 128, 130, 192) and the hollow fighting (132, 134, 194). The fighting (56, 132, 134, 194) also includes a forward, reverse pitch section (64, 162, 216). The extrusion screws (50, 52, 124, 126, 190) are designed to be used as complemental pairs as a part of twin screw processing devices (20), and are designed to impart high levels of thermal energy into materials being processed in the devices (20), without adding additional moisture.

A cavitation device is supplied by a disc pump with fluids for mixing. A cavitation rotor, having an array of cavities on its cylindrical surface, is fixed to a shaft for rotation by a motor. The disc pump and the cavitation device are beneficially in the same housing. At least one disc is spaced from and attached to the rotor near the inlet end of the cylindrical housing, so it will rotate with the rotor. A central hole in the (at least one) disc permits fluid to enter the space between the disc and the rotor; it is flung toward the peripheral space between the rotor and the cylindrical housing, where it is subjected to cavitation, and then passed to an outlet. The shaft may pass through one or both of the end walls of the cylindrical housing. The cavitation pump is especially useful for mixing oil field fluids.

A device for generating controlled formation and collapse of cavitation bubbles in a fluid. The device includes a rotor having a plurality of bore holes and a stator having a plurality of bore holes. Fluid flows into the device and passes through a space between the stator and rotor to expose the fluid to the bore holes of each component. The rotor can be rotated relative to the stator to pass the rotor bore holes across the openings of the stator bore holes to generate and collapse cavitation bubbles in the stator bore holes. The rotor bore holes may have the same diameter as the stator bore holes and the rotor bore holes preferably have depth equal to or less than the depth of the stator bore holes.

A method of hydrating a dry powdered viscosifier such as a powdered polymer is disclosed. The method includes mixing the powdered viscosifier with a solvent such as water to form a mixture; moving the mixture through a cavitation zone; inducing energetic shock waves and pressure fluctuations in the mixture by mechanically inducing cavitation events within the mixture, the shock waves and pressure fluctuations untangling, separating, and straightening polymer molecule chains and distributing the chains throughout the mixture, and extracting the resulting hydrated viscosifier from the cavitation zone.

A cavitation device is supplied by a disc pump with fluids for mixing. A cavitation rotor, having an array of cavities on its cylindrical surface, is fixed to a shaft for rotation by a motor. The disc pump and the cavitation device are beneficially in the same housing. At least one disc is spaced from and attached to the rotor near the inlet end of the cylindrical housing, so it will rotate with the rotor. A central hole in the (at least one) disc permits fluid to enter the space between the disc and the rotor; it is flung toward the peripheral space between the rotor and the cylindrical housing, where it is subjected to cavitation, and then passed to an outlet. The shaft may pass through one or both of the end walls of the cylindrical housing. The cavitation pump is especially useful for mixing oil field fluids.

A method and apparatus of inducing chemical reactions such as hydrogenation of a fluidized substance includes mixing hydrogen with the substance, passing the mixture through a cavitation zone, and inducing intense shockwaves in the cavitation zone by continuously generating high energy cavitation events within the mixture. In one embodiment, the treatment zone is the interior of a controlled cavitation reactor. Interior surfaces of the reactor may be coated with a catalyst required for the desired chemical reaction so that the catalyst need not be added directly to the mixture and need not be recovered after the reaction is complete.

Polyacrylamides, guar gum (sometimes guar), xanthan gum, carboxymethylcellulose, hydroxyethylcellulose, and other water-soluble polymers are dissolved and hydrated in aqueous solutions, including especially recycled drilling, fracturing, and other oilfield fluids having significant salt contents, by passing the water-soluble polymer together with the aqueous medium to a cavitation device including an integrated disc pump. The integration of a disc pump with the cavitation device reduces the risk of gumming by applying a negative pressure at the feed point. The ability to use water-soluble polymers with the salty recycled oilfield fluids has significant environmental benefits, namely (1) fresh water is not needed, (2) disposal of the environmentally undesirable returned fluids is not needed, (3) difficultly degradable synthetic polymers may not be needed, and, in particular, (4) the enhanced ability to use guar, which, being a natural product, is biodegradable, is environmentally favored. Although the invention is most beneficial for use with salt or brackish water, its high efficiency points to beneficial use where fresh water is the only available choice for the aqueous medium. Where dry polymer is used, the invention's benefits are especially realized in terms of logistics and handling, since viscous and bulky solutions need not be prepared and stored in advance, thus also minimizing health, safety and environmental risks