A method and apparatus for dispersing and entraining and controlling the residence time, absorption and release of gas bubbles or particles in a fluid without losing gas utilization efficiency from escaping surface gas events. A mechanical, rotating plurality of hollowed blades that induce both an axial and radial controlled circulatory flow and provide a means of gas introduction into the discharge flow that has a conical helical, axial and radial outward flow from the axis of rotation and allows entrained gas bubbles to be trapped as particles and recirculated by means of a circulatory flow back into the intake vortex of said mechanical, rotating plurality of blades. The flow is characterized by a forced intake vortex caused by a low pressure zone with a radial component, and subsequent axial component drawing fluid in a circular fashion toward the eye of the rotating device and impelling fluid.

Bioreactors are disclosed that include a vessel, a jet mixing system comprising a plurality of jet flow agitators disposed in the vessel, each jet flow agitator comprising a shaft, a shroud surrounding the shaft, the shaft having a bore and a plurality of orifices in communication with the bore, and an impeller mounted on the shaft within the shroud, and a gas delivery system configured to supply a process gas to the vessel through the bore such that the gas exits the orifices. The vessel may include a vent, and the gas delivery system may include a source of oxygen in communication with the vessel, an oxygen monitor configured to monitor the oxygen content of a liquid in the vessel, and a controller configured to adjust the oxygen content of the liquid, using the vent and oxygen source, in response to input from the oxygen monitor.

A universal wall and bridge mounted aeration apparatus has a track extending between two distinct elevations that is coupled to a wall and bridge mount. An aeration unit is pivotally coupled to the track and has an aerator adapted to operatively at least partially submerge within and aerate a liquid. A selective mover or drive is adapted to operatively move the aeration unit along the track and thereby vary an elevation of the aeration unit. The universal wall and bridge mount supports the track and aeration unit. The universal wall and bridge mount has a first configuration for mounting to a structure such as a stationary bridge, and a second configuration for mounting to a wall. The universal wall and bridge mounted aeration apparatus may be adjusted to position the propeller after installation under the surface of the liquid through three axes of motion freedom.

Disclosed herein is a disperser which can be easily installed without any air pump, a transfer pope and a porous disperser in such a way to install an impeller, which is employed to discharge water and at the same time to suck air, at an end portion after a shaft employed to transfer the driving force of a driving motor has been connected underwater, wherein the disperser of the present inventive concept is easy to maintain without cleaning due to the plugging, whereupon maintenance is easy and the applicability of the product is good.

A method and apparatus for injecting a gas into a liquid in which a rotating helical impeller within a draft tube submerged in the liquid creates a liquid flow within the draft tube. Gas bubbles are injected into the draft tube either above or below or alongside the helical impeller or in all three locations. The liquid is drawn into the draft tube with a superficial velocity greater than a substantially uniform terminal ascent velocity of the gas bubbles to allow entrainment of undissolved gas bubbles in the bulk liquid into the liquid being drawn into the draft tube. The gas bubbles are injected with a uniform diameter of between about 10.0 microns and about 1.0 millimeters. The small bubble size enhances the dissolution of the gas into the liquid and also allow the entrainment of the gas into the liquid being drawn into the draft tube.

A gas-saturated liquid generator having a vessel of the generator, a hollow bell in its upside down position located with a tube for gas supply, and a mixer situated in the area for saturated liquid covered by the bell is disclosed. The entire bell is submerged below the surface of the saturated liquid. On a shaft projecting from a driving equipment, the mixer provided with a foaming spring is situated. The mixer provided with a magnetic carrier seated rotatably on the protrusion formed by a bulge in the bottom part of the generator vessel may be used. The preferred bell forms are dome-shaped, cylindrical or conical.

A method and apparatus for injecting a gas into a liquid in which a rotating helical impeller within a draft tube submerged in the liquid creates a liquid flow within the draft tube. Gas bubbles are injected into the draft tube either above or below or alongside the helical impeller or in all three locations. The liquid is drawn into the draft tube with a superficial velocity greater than a substantially uniform terminal ascent velocity of the gas bubbles to allow entrainment of undissolved gas bubbles in the bulk liquid into the liquid being drawn into the draft tube. The gas bubbles are injected with a uniform diameter of between about 10.0 microns and about 1.0 millimeters. The small bubble size enhances the dissolution of the gas into the liquid and also allow the entrainment of the gas into the liquid being drawn into the draft tube.

Biomass feedstocks (e.g., plant biomass, animal biomass, and municipal waste biomass) are processed to produce useful products, such as fuels. For example, systems are described that can convert feedstock materials to a sugar solution, which can then be fermented to produce ethanol. Biomass feedstock is saccharified in a vessel by operation of a jet mixer, the vessel also containing a fluid medium and a saccharifying agent.

A gas dispersion system may include a drive mechanism, a drive shaft having a proximal end operably coupled to the drive mechanism, extending to a distal end, and configured to transfer rotational motion and torque, a mixing element arranged at or near the distal end of the drive shaft including a hub and multiple blade pairs, each blade pair including an upper blade and a lower blade secured to the hub and cantilevering freely and generally radially away from the hub.