Abstract: Process and apparatus for the production of algae biopolymer employing a first stage for the growth of algae and a second stage for biopolymer production. In the first stage, growth of algae biomass in a culture medium is accomplished by operating the first stage in a continuous mode in which fresh nitrogen-containing nutrient medium is supplied to the culture. Concomitantly with the supply of fresh nutrient medium to the culture in the first stage, a portion of the culture medium is transferred from the first stage to the second stage in which the supply of nitrogen is limited. A nitrogen deficiency is created in the second stage to shift the culture to a senescent phase to enhance biopolymer production. The growth phase is carried out in a first stage reaction chamber which is connected to a plurality of second stage reaction chambers in parallel with one another.

Abstract: A process for the recovery of uranium from a saline alkaline lixiviant employed in a uranium leaching operation. An ion exchange resin is employed to adsorb uranium from the lixiviant. Prior to contacting the resin with the lixiviant, the pH of the lixiviant is reduced to a value of less than 7. By this technique, the resin loading in the presence of chloride ion is materially increased. The pH values for optimum resin loading capacity decrease as the salinity of the lixiviant increases. Resin loading is also enhanced by the presence of bicarbonate ion in the lixiviant.

Abstract: A process for dynamically killing a well blowout by means of a relief well. A low density fluid is pumped down the relief well and into the blowout well at a rate to produce a frictional pressure loss in the blowout well which when added to the hydrostatic pressure in the blowout well is greater than the static formation pressure but less than the formation fracturing pressure. Injection of the low density fluid is continued until the blowout well goes from two-phase to single-phase flow. Thereafter, a high density fluid such as a drilling mud is pumped down the relief well and into the blowout well. This fluid produces a hydrostatic pressure in the blowout well which is greater than the static formation pressure.

Abstract: Waterflood oil recovery process involving the use of an amphoteric polyelectrolyte as a thickening agent for mobility control. The amphoteric polyelectrolyte is a copolymer of a quaternary vinyl pyridinium sulfonate and a water-insoluble alpha olefin or hydrogenated diene. Specifically disclosed are vinyl pyridinium sulfonate-styrene block copolymers. The amphoteric polyelectrolytes are stable in high temperature and high brine environments.

Abstract: Process for the recovery of oil from a subterranean oil reservoir involving the injection into the reservoir of an aqueous solution of an amphoteric surfactant having an inner quaternary ammonium group linked to a terminal sulfonate or carboxylate group. The amphoteric surfactants may be employed in relatively low concentrations within the range of 0.0005 to 0.1 weight percent and injected in a slug of at least 0.5 pore volume. The invention may be applied in situations in which the reservoir waters and/or the waters employed in formulating the surfactant solution contain relatively high amounts of divalent metal ions. Specifically disclosed amphoteric surfactants include hydrocarbyl dialkyl or dihydroxyalkyl ammonium alkane sulfonates and carboxylates in which the hydrocarbyl group contains from 8 to 26 carbon atoms.

Abstract: A technique is provided for assaying the formations surrounding a borehole for uranium-bearing ore. A borehole logging tool employs a pulsed neutron source to cyclically irradiate the formations with neutrons. The tool measures neutron fluxes produced during the period of time that prompt neutrons are being produced by the neutron fission of uranium in the formations. The tool also measures the total neutron fluxes produced in response to each burst of the neutron source, such measurements being utilized to correct the neutron flux response of the borehole logging tool during the prompt fission neutron period for the effects of epithermal/thermal neutron moderation, scattering, and absorption within the borehole itself.

Abstract: Waterflood process for the recovery of oil from a subterranean oil reservoir in which at least a portion of the injected water is thickened by the addition of a surface-active amphoteric quaternary ammonium sulfonate and an aliphatic alcohol containing from 5 to 8 carbon atoms. The alcohol is employed in a concentration to provide a ratio of the volume amount of alcohol in the solution to the weight amount of the amphoteric sulfonate within the range of 0.1-0.6 to produce a pronounced thickening effect. The alcohol-amphoteric sulfonate systems are useful viscosifiers in highly saline systems.

Abstract: Process for the in-situ leaching of uranium from a subterranean ore deposit comprising introducing into the deposit an aqueous lixiviant having a pH of at least 6.0 and containing an alkali metal sulfate leaching agent. The alkali metal sulfate may be employed in combination with an alkali metal carbonate or bicarbonate with the sulfate comprising the predominant leaching agent. The lixiviant may be at a pH of at least 7.5 and contain an alkali metal sulfate leaching agent and a hypochlorite oxidizing agent.

Abstract: A system for assaying for neutron-fission-producing ore in the formations traversed by a borehole includes a pulsed neutron source and a neutron detector. The source is operated to irradiate such ore-bearing formations with fast neutrons, and the detector responds to the delayed fission neutrons emitted by the ore as a measure of ore concentration. The source is also operated to irradiate nonneutron-fission-producing ore-bearing formations with fast neutrons, and the detector responds to the delayed neutrons from oxygen-17 as a measure of the neutron output of the source. The measurement of ore concentration is corrected in accordance with the measured changes in the neutron output of the source.

Abstract: Waterflooding process for the recovery of oil for a subterranean formation in which at least a portion of the injected water is thickened by the addition of a sulfonated polyethoxylated aliphatic alcohol surfactant. The thickened water has a salinity within the range of 5-18 percent. The sulfonated polyethoxylated aliphatic alcohol has at least two ethylene oxide units to provide an HLB within the range of 10.0-14.0 and the lipophilic base contains from 16 to 20 carbon atoms. The thickened surfactant slug may be preceded by the injection of a relatively low viscosity surfactant slug and viscosity gradation of the thickened surfactant slug may be accomplished by varying the salinity and/or the concentration of the sulfonated polyethoxylated aliphatic alcohol.

Abstract: A radioactivity borehole logging sonde includes a pulsed neutron source and a gamma-ray detector. A cylinder of a material susceptible to neutron activation is positioned about the neutron source before or after a radioactivity logging operation. The neutron source is turned ON to activate the material of the surrounding cylinder. After activation, the neutron source is turned OFF and the cylinder is moved to a position about the gamma-ray detector. The gamma-ray detector monitors the radiation from the activated cylinder as a measure of the output from the neutron source.

Abstract: A technique is provided for assaying the formations surrounding a borehole for uranium. A borehole logging tool cyclically irradiates the formations with neutrons and responds to neutron fluxes produced during the period of time that prompt neutrons are being produced by the neutron fission of uranium in the formations. A borehole calibration tool employs a steady-state (continuous output) neutron source, firstly, to produce a response to neutron fluxes in models having known concentrations of uranium and, secondly, to produce a response to neutron fluxes in the formations surrounding the borehole. The neutron flux responses of the borehole calibration tool in both the model and the formations surrounding the borehole are utilized to correct the neutron flux response of the borehole logging tool for the effects of epithermal/thermal neutron moderation, scattering, and absorption within the borehole itself.

Abstract: A gamma-gamma density logging tool employs a gamma-ray source and a pair of gamma-ray detectors. A first detector receives only natural gamma rays from the formations surrounding the borehole. A second detector receives both natural gamma rays and scattered gamma rays from the formations surrounding the borehole. The count rate from the second detector is modified by the count rate of the first detector to provide for a density measurement that is corrected for the effects of natural gamma radiation from radioactive ore-bearing zones in the formations.

Abstract: A method for the recovery of oil from an oil-containing subterranean formation by waterflooding employing as an injection medium an aqueous solution of a viscosifier comprising the water-soluble reaction product of an organic polyisocyanate and the addition product of an alkylene oxide and linear, non-ionic polysaccharide, said addition product having a molecular weight of at least about 100,000. According to a preferred form of the invention, a polyisocyanate cross-linked hydroxyethyl cellulose is utilized as a viscosifier to decrease the mobility ratio between the injected water and oil, thereby improving the efficiency of the waterflood. The novel viscosifiers which comprise one form of the invention are characterized by an improved resistance to the effect of divalent metal ions present in the formation as well as a thermal stability which is superior to that of the viscosifiers currently used in waterflooding operations.

Abstract: Waterflood process for the recovery of oil from a subterranean oil reservoir involving injecting into the reservoir an aqueous solution of an amphoteric surfactant having an inner sulfonium group linked to a terminal sulfonate group. The amphoteric sulfonium sulfonate may be employed in relatively low concentrations within the range of 0.001-0.1 weight percent and injected in an aqueous slug of at least 0.5 pore volume. The invention may be applied in situations in which the reservoir waters and/or the waters employed in formulating the surfactant solution contain relatively high amounts of divalent metal ions. Specifically disclosed sulfonium sulfonates include dodecylmethylsulfonium propane sulfonate, tetradecylmethylsulfonium propane sulfonate, and hexadecylhydroxyethylsulfonium propane sulfonate.

Abstract: Waterflood oil recovery process employing a Xanthomonas polysaccharide as a thickening agent in which the aqueous polysaccharide solution contains a C.sub.3 -C.sub.5 aliphatic alcohol. The aliphatic alcohol functions to stabilize the polysaccharide against thermal degradation in reservoirs having temperatures in excess of 60.degree. C. The polysaccharide solution may also contain an alkali metal carbonate which functions with the alcohol to impart further stability to the Xanthomonas polysaccharide solution.

Abstract: A surfactant waterflooding process employing an anionic surfactant for use in oil reservoirs in which the connate waters exhibit high salinities and/or divalent metal ion concentrations in situations in which the available waters exhibit high salinities and/or divalent metal ion concentrations. The anionic surfactant comprises a hydrocarbyl amino ether-linked alkane sulfonate in which the hydrocarbyl group provides a lipophilic base and in which the ether linkage is provided by an alkoxy linkage having a ratio of carbon atoms to oxygen atoms within the range of 2 to 3. The surfactant may be a monosulfonate or disulfonate and may be employed alone or in conjunction with other additives. Thus it may be employed as a cosurfactant in combination with other anionic or nonionic surfactants or in combination with alcohols which function as surfactant cosolvents.

Abstract: The recovery of oil by surfactant waterflooding involving the injection of a hydrocarbon slug followed by a thickened aqueous surfactant slug. The hydrocarbon slug is injected into the reservoir in an amount of at least 0.02 pore volume and has a viscosity less than that of the reservoir oil. The thickened surfactant slug comprises an aqueous solution of a surfactant system which includes an organic sulfonate surfactant and which functions to increase the viscosity of the aqueous liquid to a value at least as great as the viscosity of the reservoir oil while decreasing the oil-water interfacial tension. The surfactant slug may include one or more organic sulfonates, either alone or in mixture with a water-soluble aliphatic alcohol.

Abstract: A method for the recovery of oil from an oil-containing subterranean formation by waterflooding employing as an injection medium an aqueous solution of an anionic surfactant comprising a hydrocarbyl substituted succinimido aryl sulfonate and/or its succinamic acid derivative. Such surfactants retain their detergency and do not precipitate in aqueous systems containing high concentrations of brine, e.g., over 20,000 ppm Ca.sup.++, over 10,000 ppm Mg.sup.++ and over 50,000 ppm Na.sup.+. These surfactants are effective in mobilizing tertiary oil under highly saline environments and demonstrate low adsorptive losses. When used as cosurfactants, these materials significantly improve the brine tolerance of more sensitive surfactants, such as petroleum sulfonates.

Abstract: Waterflooding process for the recovery of oil from a subterranean oil reservoir which involves the injection into the reservoir of an aqueous solution of an aliphatic substituted succinimido aryl hydroxy sulfonate or its corresponding succinamic acid derivative. This surfactant functions to reduce the oil-water interfacial tension and also functions in the presence of divalent metal ions, such as calcium or magnesium, as a thickening agent to increase the viscosity of the injected water. In carrying out the invention in oil reservoirs in which the connate waters exhibit a divalent metal ion concentration of at least 0.2 weight percent, the surfactant may be injected in a relatively fresh water which exhibits a divalent metal ion concentration less than that of the reservoir water. Thus as the surfactant solution mixes with the reservoir water, the divalent metal ion concentration of the solution is increased with an attendant increase in its viscosity.