An activated sludge sewage treatment process which includes a mixed liquor tank and a pressure vessel much smaller in size than said mixed liquor tank. At least a portion of the influent to said tank is directed to the pressure vessel where oxygen is dissolved therein under superatmospheric pressures. The pressure is then released and said portion of the influent gently transferred into said mixed liquor tank so that substantially all of the dissolved oxygen remains in solution until said influent portion is mixed with the sewage in the mixed liquor tank to thereby raise the dissolved oxygen concentration in the tank.

A gas transfer system adapted to dissolve a gas or other compressible fluid in a relatively non-compressible liquid such as waste water with a minimum expenditure of energy. The system makes use of a drum divided by radial vanes into liquid chambers. Rotation of the vanes causes the chambers to rotate about the central axis of the drum whereby in the course of every operating cycle, each chamber is brought into operative relation with the respective interfaces of an inflow station, a gas transfer station and an outflow station. At the inflow station, raw liquid to be treated is fed into the chamber then in operative relationship therewith to produce a liquid batch therein. Concurrently, at the transfer station another batch of raw liquid in the chamber then in operative relation therewith is subjected to pressurized gas to effect the absorption of the gas by the liquid. At the outflow station, the treated batch of liquid in the chamber then in operative relation therewith is discharged to empty this chamber so that it can be refilled with raw liquid and the cycle repeated.

A system for performing an oxygenation process within a body of sewage at atmospheric pressure includes an oxygen absorber coupled to an oxygen supply at superatmospheric pressure. A storage vessel has an elongate chamber therein which is oriented vertically in the system. Pipes and valves are coupled to the upper and lower ends of the chamber so that the chamber is alternately communicated with the oxygen absorber and the body of sewage, thereby providing alternate high pressure and low pressure half cycles respectively. Initially, oxygenated liquor at superatmospheric pressure is in the oxygen absorber and the elongate chamber is filled with a quantity of low oxygen content liquor at atmospheric pressure. The valves are then operated during the high pressure half cycle to admit oxygenated liquor into the elongate chamber through the lower end and to simultaneously expel liquor and undissolved oxygen from the upper end into the oxygen absorber. The valves are then operated during the low pressure half cycle to reduce the chamber pressure to atmospheric and to admit a quantity of liquor from the body of sewage into the elongate chamber through the top end while simultaneously expelling the oxygenated liquor from the bottom end into the body of sewage. Thus, oxygen which comes out of solution and collects as relatively large bubbles as the pressure in the chamber is reduced to atmospheric pressure, will be retained in the elongate chamber and returned to the oxygen absorber during the next high pressure half cycle. A preferred embodiment of the invention includes two or more storage vessels alternately operated during the high and low pressure half cycles to provide a substantially continuous flow of liquor into and out of the pressurized oxygen absorber.

Apparatus to increase the level of oxygen ingested by livestock by oxygenation of the livestock water supply includes an enclosed tank having a top and having an inlet for admitting water from a supply of water and an outlet for discharging water from the tank. The tank has a first inlet port for introduction of compressed air into the tank from an air compressor. The tank has a second inlet port for allowing introduction of hydrogen peroxide. A float is located in the tank to selectively control the introduction of compressed air into the tank by activation of the air compressor when the water level reaches a preselected high point as the water in the tank absorbs oxygen from the air pocket above the water level. The float also opens a valve in an overflow tube disposed within the tank and keeps the valve open until the float reaches a predetermined low point as water is forced out the overflow tube by compressed air entering the tank. When the low point of the float is reached, a timer begins to run for a preselected interval. The timer causes the air compressor to continue to force compressed air into the tank and the valve in the overflow tube remains open while the air compressor is operating.

A batch water treatment system is provided in which ozone is the reactive agent. The system includes a holding tank containing untreated water in communication with a reaction tank in which ozone is dispersed under pressure through a plurality of foraminous diffusers which are connected to a modular ozone generator. Impurities contained in the water are oxidized or broken down by the ozone into forms capable of filtration, and as this treatment process progresses the water is circulated through a conduit to a monitor which measures the level of impurities in the water. Once a predetermined proportion of impurities are broken down and filtered from the system, the monitor automatically activates a drain line to evacuate the reaction tank of the treated water and then refills it with more untreated water from the holding tank to repeat the process.