Abstract: An apparatus for mixing gas and liquid is disclosed. The apparatus includes a draft tube having a gas conduit, a liquid inlet and a gas-liquid outlet, and an impeller rotatably mounted within the draft tube. The gas can be entrained into the liquid by rotation of an impeller having relatively high angular velocity, which generates relatively low axial velocity of the liquid and relatively low angular velocity of the liquid. Floats may support the impeller and the impeller may maximize aeration of the liquid.

Abstract: An apparatus for mixing gas and liquid is disclosed. The apparatus can comprise a draft tube having a gas conduit, a liquid inlet and a gas-liquid outlet, an impeller rotatably mounted within the draft tube. The gas can be entrained into the liquid by rotation of an impeller having relatively high angular velocity, which generates relatively low axial velocity of the liquid and relatively low angular velocity of the liquid. Floats may support the impeller and the impeller may have means for maximizing aeration of the liquid.

Abstract: An apparatus for mixing gas and liquid is disclosed. The apparatus may have a plurality of blades rotated about a common shaft. The blades may have a forward portion, which cuts through a liquid, and a trailing portion, which forms the leading part of a gas cavity. The gas cavity is in communication with a gas inlet and the bulk fluid. As the blades pass through a liquid, a reduced pressure zone is formed immediately behind the blade. The reduced pressure zone allows air to be aspirated from the gas inlet into the gas cavity adjacent to the blade. Gas in the gas cavity is sheared into discrete bubbles and transferred to the liquid by the action of the trailing blade wake currents.

Abstract: An apparatus for mixing gas and liquid is disclosed. The apparatus can comprise a draft tube having a gas conduit, a liquid inlet and a gas-liquid outlet, an impeller rotatably mounted within the draft tube. The gas can be entrained into the liquid by rotation of an impeller having relatively high angular velocity, which generates relatively low axial velocity of the liquid and relatively low angular velocity of the liquid. Floats may support the impeller and the impeller may have means for maximizing aeration of the liquid.

Abstract: A surface aerator for mixing gas and liquid is disclosed. The surface aerator has an upwardly pumping impeller located within a draft tube. A flow diverter redirects pumped liquid from the impeller traveling in an upward direction to a radially outward direction where it impacts and aerates the remaining liquid in a vessel. A baffle extends radially at a shallow depth to a point beyond the impact area of the liquid to provide separation of the impact area from the rest of the liquid and promote aeration.

Abstract: A wastewater separation system for separating an aqueous phase from an organic phase comprising oil, fat and/or grease in wastewater is disclosed. The wastewater may be collected from restaurant grease traps, as well as other food preparation facilities, schools, hospitals, processing plants and the like. A separator, such as a centrifugal separation device, comprises a wastewater inlet, an organic phase outlet for discharging low density liquid and solids and an aqueous phase outlet for discharging water and possibly other high density liquids and solids. The system can be portable and can be mounted on a vehicle for collection and treatment at various sites. Heat can be introduced to the system to accelerate the separation of the aqueous phase from the organic phase of the wastewater.

Abstract: An apparatus for mixing gas and liquid is disclosed. The apparatus includes a draft tube having a gas inlet, a liquid inlet, a gas-liquid outlet, and an impeller rotatably mounted within the draft tube. The gas can be entrained into the liquid by rotation of an impeller having a low pitch ratio, such as less than 1:1. The impeller can have a diameter than is greater than the axial length of the impeller and includes at least one blade extending at least 30° around an axis of rotation of the impeller. Liquid turning vanes can also be positioned external to the draft tube to rotate liquid entering the draft tube in a direction opposite the direction of rotation of the impeller. The impeller can be constructed to create a reduced pressure zone, which directs gas axially downward within the draft tube upon rotation of the impeller.

Abstract: An apparatus for mixing gas and liquid is disclosed. The apparatus may have a plurality of blades rotated about a common shaft. The blades may have a forward portion, which cuts through a liquid, and a trailing portion, which forms the leading part of a gas cavity. The gas cavity is in communication with a gas inlet and the bulk fluid. As the blades pass through a liquid, a reduced pressure zone is formed immediately behind the blade. The reduced pressure zone allows air to be aspirated from the gas inlet into the gas cavity adjacent to the blade. Gas in the gas cavity is sheared into discrete bubbles and transferred to the liquid by the action of the trailing blade wake currents.

Abstract: The specification discloses a system and method for producing a particulate MBOCA product including relatively uniformly sized granules. The system includes a pan granulator, a dust hood enclosing the granulator pan, and a blower for circulating an air stream through the hood to carry away the heat of fusion of the granulation. In a second aspect, the system includes a novel drum charging apparatus having a filler tube extendable into a drum, a dust cup covering the drum opening when the filler tube is inserted therein, and a vacuum for drawing air through the dust cup. Air displaced from the drum and product particles dispersed therein are therefore drawn into the vacuum for subsequent recovery of product particles.

Abstract: A method of neutralizing and detoxifying waste material containing both an acid and a toxic organic compound. The waste material is combined with sufficient oil and sufficient caustic to form a pumpable slurry having a pH of 7 or higher. The oil is then separated from the slurry leaving a dry, deoiled material, containing a salt and the toxic organic compound. This material is pyrolyzed at a temperature below the melting point of the salt and sufficiently high to vaporize the toxic organic compound. The resultant vapor is then incinerated to detoxify the vaporized organic compound.