New Patents XV

rotary disc screen while the remainder of the material is delivered to the apparatus for gravita- tional classification as between the uncrushables and shreddables in response to air flow in a con- trolled atmosphere to promote gravity fall-out separation of the heavier components from the lighter components.

4733724

VISCOUS OIL RECOVERY METHOD

Ricardo Cardenas, Robert B Alston assigned to Texaco Inc

4731232

PROCESS FOR THE PURIFICATION OF INDUSTRIAL

GASES OR WASTE GASES

Joachim Fischer, Helmut Knorre, Rodenbach, Federal Republic Of Germany assigned to Degussa AG

In purifying gas wash waters containing cyanide with formaldehyde, the exact dosing of formal- dehyde presents a problem, especially with strongly fluctuating cyanide contents. By con- tinuous potentiometric measurement in a side stream which is regulated to a pH of 7 to 10, while the pH of the main stream remains unchanged, the formaldehyde can be adjusted safely to any cyanide content.

4733605

PROCESS AND DEVICE FOR PURIFYING POLLUTED AIR

Our invention concerns a method for treating a well completed in a subterranean petroleum- containing formation which will improve the rate at which steam can be injected into the for- mation for a steam push-pull or steam drive oil recovery method. This preconditioning process is applied to formations exhibiting very limited steam receptivity because the formation contains high oil viscosity and has high oil saturation and is completely liquid filled. The method involves injecting a mixture of a non-condensable oil- insoluble gas such as nitrogen and an oil soluble gas such as carbon dioxide all in the gaseous phase into the formation at a controlled rate which will avoid permanently fracturing the for- mation and also avoid the immediate formation of an oil bank due to dissolution of the injected oil soluble gaseous fluid into the oil. Ideally by controlling the injection rate, the gaseous mix- ture first displaces water from the flow channels and then carbon dioxide slowly dissolves in the oil while nitrogen remains in the flow channels. Steam injection can then be applied to the forma- tion without the previously experienced loss in steam injectivity.

Hein Holter, Heinrich Igelbuscher, Heinrich Gresch, Heribert Dewert, 4390 Gladbeck, Federal Republic Of Germany assigned to Hol- ter Heinz

4734159

EVAPORATION APPARATUS

A chemisorption filter is provided for receiving contaminated air to be filtered and partially heating the air while filtering same, with a fur- ther heater downstream of the chemisorption fil- ter for further heating the air. A catalyst mass is traversed by the air heated by the heater and dis- posed downstream of the heater for further purifying the air, with further device dow- nstream of the catalyst mass for cooling the air upon passage thereof through the catalyst mass, all of the devices collectively forming an air purifier to a passenger compartment of an auto- mobile for supplying the compartment with purified air. A sensor is provided behind the radiator of the automobile and contacted by the air displaced therethrough by a fan, the sensor detecting contaminant levels in the external air before it is admitted to the chemisorption filter, for controlling the on/off operation of the air purifier.

Theodore Korenowski assigned to T F K Com- pany Inc

Apparatus and method for using a heated waste gas stream to evaporate a volatile component such as water or a solvent from a liquid solution comprises a flue to feed the gas stream from the source of heated gas; a container having an inner chamber to hold the liquid for evaporation of the volatile compound and an outer chamber con- nected to the flue which forms a gas channel sub- stantially surrounding the inner chamber through which at least a portion of the gas stream flows to supply heat to the inner chamber and evaporate the volatile component of the li- quid solution; an inlet to feed the liquid solution into the inner chamber; upper and lower liquid level sensors to control the quantity of liquid solution fed into the inner chamber to establish a liquid level therein; a sparger for agitating the li-