Separate Oil Phase Research Articles

Observations on the Primary Migration of Oil in the la Luna Source Rocks of the Maracaibo Basin, Venezuela

In the present work, an integrated approach has been made to understand the primary migration of oil in the organic-rich, oil prone, predominantly carbonate source rocks of the La Luna Formation of the Maracaibo Basin. Geochemical data on source rock extracts and the simulation of oil generation by hydrous-pyrolysis experiments indicate that the primary migration and expulsion of oil began at an early stage of thermal maturity and that the bulk oil expulsion at peak generation could have been as high as 75%. Fluorescence and transmitted light petrography of the source rocks at different maturity levels show the dominant mode of oil expulsion through microfractures. It is interpreted from the geochemical and geological data that the primary migration of oil in the La Luna source rocks took place as a separate oil phase through microfractures caused by the excess fluid pressure due to hydrocarbon generation. The oils expelled from the La Luna source are enriched in saturated hydrocarbons and depleted in resins + asphaltenes compared to the La Luna rock extracts. However the distributions of n-alkanes, in the oils and the rock extracts are very similar, which suggest that fractionation of the n-alkanes did not occur during the primary migration. In the Maracaibo Basin, updip lateral primary migration of oil within the La Luna source system seem to have occurred for a considerable distance. Local internal migration has been observed at a relatively early stage of maturity.

Characterisation of the ageing of cold rolling emulsions by differential scanning calorimetry

In cold rolling of steel different oil-water emulsions are used for lubrication and cooling. The emulsions are subjected to ageing in use and different analytical methods are applied to control the function of the emulsions. A method is described in which the change in function is followed by determination of an “Oxidation onset temperature” of the separated oil phase of the emulsion. It is shown that this temperature is successively increased with the time of use.

Solubilization and localization of cholesteryl oleate in egg phosphatidylcholine vesicles. A carbon 13 NMR study.

Co-sonicated mixtures of egg phosphatidylcholine and small amounts (less than or equal to 4%, w/w) of [carbonyl-13C]cholesteryl oleate have been studied by 13C NMR spectroscopy at 50.3 MHz. The carbonyl chemical shift from cholesteryl oleate solubilized in vesicles was 1 ppm downfield from the carbonyl chemical shift of cholesteryl oleate present in a separate oil phase. The maximum solubility of the steroid in vesicles determined by chemical analysis of purified vesicles was 1.6 weight % (approximately 2 mol %), in close agreement with the maximum solubility estimated from NMR speak intensity measurements (1.4 weight %). The downfield shift indicates hydrogen bonding of solvent (H2O) molecules with the cholesteryl oleate carbonyl group, suggesting that vesicle-solubilized cholesteryl oleate molecules are located in the phospholipid bilayer with the carbonyl group close to the aqueous interface and the sterol ring and fatty acyl chain approximately parallel to the fatty acyl chains of the phospholipid. Such a folded conformation and localization of the carbonyl group at the aqueous interface may facilitate interactions of sterol esters with cholesterol ester transfer proteins and cholesterol esterases.

Solubilization and localization of triolein in phosphatidylcholine bilayers: a 13C NMR study.

Cosonicated mixtures of egg phosphatidylcholine and small amounts (less than 5% wt/wt) of triolein have been studied by 13C NMR spectroscopy. The 50.3-MHz 13C NMR spectrum of vesicles preparations containing 90% isotopically substituted [1-13C]triolein showed two carbonyl resonances at chemical shift values that indicate hydrogen bonding of H2O molecules with the carbonyl groups. The extent of hydration, estimated from the chemical shift values that indicate hydrogen bonding of H2O molecules with the chemical shift values (173.07 ppm and 172.39 is approximately 50%. The data suggest that the triolein is located in the bilayer with the three carbonyl groups at the aqueous interface. The acyl chains are extended toward the bilayer interior, with a conformation of the glyceryl region such that the primary (alpha) carbonyls are closer to the aqueous medium than is the secondary (beta) carbonyl. Thus, triolein is present in the bilayer in an orientation appropriate for enzymatic hydrolysis, with the second substrate (H2O) in close proximity to the hydrolytic site, and with a conformation that could explain, in part, enzymatic specificity for hydrolysis at the alpha position. Spectra of vesicles containing greater than or equal to 3% triolein showed two additional carbonyl peaks characteristic of pure (neat) triolein. This allowed a determination of the maximum solubility (approximately 2.8%) of surface-oriented triolein in the bilayer phase. Beyond this limit all excess triolein partitions into a separate oil phase.

Improving Heater Treater Fuel Efficiency

This paper describes a program carried out to find the most cost-effective method of increasing the combustion efficiency of direct-gas-fired heater treaters. A mobile combustion analysis system was used to pinpoint areas of heat loss in production treaters. Data were used to define an efficiency improvement program that ultimately cut fuel consumption in the test field by 67%. Introduction The ever-increasing shortage of fossil fuels in the world today recently began to show its effects in the production of oil and gas. In most cases, the heat production of oil and gas. In most cases, the heat required to break a produced emulsion into separate oil and water phases is provided by a heater treater. The traditional source of fuel for heater treaters is the produced gas from the emulsion being separated. Until recently, lease gas has been plentiful, and very little, if any, attention has been paid to producing or maintaining a heater treater that burns gas in an efficient manner. The recent increase in commercial gas prices combined with a decline in gas/oil ratios in older fields and enhanced recovery operations suddenly finds many production personnel highly concerned about the efficient use of fuel gas. This paper describes a series of combustion-efficiency paper describes a series of combustion-efficiency improvement tests conducted on treaters in Gulf Oil Corp's Baxterville field in southern Mississippi. The study was defined to investigate the overall performance of heater treaters in terms of design, performance of heater treaters in terms of design, manufacturing, theoretical performance, and actual field operating characteristics. The information permits an evaluation of actual unit efficiency and permits an evaluation of actual unit efficiency and pinpoints areas of maximum energy waste and pinpoints areas of maximum energy waste and possible methods of increasing efficiency. possible methods of increasing efficiency. Preliminary Efficiency Study Preliminary Efficiency Study Program Description Program Description The heater treater study was defined by a six-step project outlined as follows: (1) obtain information project outlined as follows:obtain information from the treater industry on present design and manufacturing processes, as well as any research or design changes aimed at energy conservation,conduct a field examination of existing treaters to obtain information on actual operating characteristics,analyze the results of the field study to determine efficiency and pinpoint areas of maximum heat loss,scrutinize the industry-proposed unit modifications from Step 1 in terms of the field data to determine which alterations would produce the largest efficiency increase,retrofit field units with selected equipment and related process-monitoring instruments to permit a determination of the efficiency improvement that could be expected from any given change in treater configuration, andif the results of experimental retrofitting so dictated, modify all field units with similar equipment. Information Search Seven major heater treater manufacturers were contacted to gather state-of-the-art information on treater design, construction, and operation. It commonly was acknowledged that the basic gas-fired heater treater, as sold, is an inherently inefficient device because there has been no demand for a more fuel-efficient device. Considering the abundance of cheap gas in the past, and the highly cost-competitive nature of the treater industry, it was deemed senseless by manufacturers to incur higher costs by incorporating energy conservation measures in a market where they were not considered necessary. JPT P. 971

Stability test of O/W-emulsion stabilized with nonionic surfactant by centrifugation and HLB (author's transl)

The stability against separation of oil phase from 25% liquid petrolatum-water emulsions stabilized with 0.5% mixed surfactants of sorbitan-fatty acid monoesters and polyoxyethylene sorbitan-fatty acid monoesters was evaluated by centrifugation. Reproducibility of the centrifugal test was very good. Result of the test after aging was closely related to the induction period of oil phase separation and the quantity of separated oil phase after a long-time storage of the emulsions. Change of the specific interfacial area with time revealed that the stabilizing effect is better for a single hydrophilic surfactant with maximum hydrophile-lypophile balance (HLB) than for any mixed surfactant in the relation of HLB value with stability. It thus appears that the so-called "optimum HLB value" determines the best dispersibility, because the specific interfacial area immediately after emulsification shows a maximum value at the "optimum HLB value" while the best stabilizing effect is not attained.

非イオン性乳化剤を用いたO/Wエマルションの安定性に影響する要因と最適HLB

The concentrations of surfactant and oil, emulsifying method, and interfacial tention were examined as the possible factors affecting the stability of liquid petrolatum-water emulsions stabilized with mixed surfactants of sorbitan monolaurate and polyoxyethylene sorbitan monolaurate in its relation to hydrophile-lypophile balance (HLB) value. The so-called "optimum HLB value" is obtained by the water phase separation test. This is closely related to the particle size and flow properties, but has little or no relation to the properties of interfacial film. On the other hand, oil phase separation test can be considered to evaluate the coalescence of oil droplets in relation to the properties of interfacial film. Change in the surfactant composition affected oil phase separation in relation to the interfacial tention. The conventional screening method for emulsifying agants by the HLB concept was criticized on the basis of the present investigation.

The composition of lipids in intestinal digesta of young pigs receiving diets containing tallow and tallow fatty acids

Three semipurified diets containing a low level of fat or 10 percent of either beef tallow or beef tallow free fatty acids were fed to young pigs. Jejunal digesta was sampled 1.5, 2.5, 3.5, and 4.5 h after feeding by aspiration through tubes leading from the jejunal lumen to the exterior. The samples were forced through Millipore filters (1 x 10(-7) m pore size) to separate aqueous phase and oil phase lipid. The total and aqueous phase lipid was separated into triglyceride, monoglyceride, and free fatty acid, and the fatty acid composition of each fraction determined. The concentration of aqueous phase lipid was not influenced by diet, although the concentration of the oil phase lipid was generally higher for the addition of fat to the diets; the increase was greater for the beef tallow free fatty acid diet than for the beef tallow diet. Free fatty acids were the predominant component of the aqueous phase lipid along with some monoglyceride and traces of triglyceride. The major component of the oil phastions of triglyceride and monoglyceride. These must have been derived from endogenously secreted lipid in the case of the tallow fatty acid diet. Thus, the lower digestibility of completely hydrolyzed beef tallow than of conventional beef tallow was not due to an absence of monoglyceride in the intestinal lumen. The proportion of stearic acid in the jejunal digesta was greater than in the dietary lipid, whereas there were lower proportions of palmitic and oleic acids in the jejunal digesta than in the diet; the effect being most pronounced for the tallow free fatty acid diet. The ratio of oleic to palmitic acid in the aqueous phase was less than in the lipid phase suggesting preferential uptake of oleic acid from the micelle by the intestinal mucosa.

乳剤に関する研究 (第1報)

It is well known that the homogenizer is a very effective equipment for O/W emulsification. However, when the preliminary emulsion containing a large amount of oil as the internal phase was processed with the Hydropulse homogenizer at high pressure, it happened to decrease the emulsion viscosity and increase the specific resistance. The phenomenon was found to be a phase inversion with partial separation of oil phase and this occurred at a lower processing pressure when the oil phase volume was larger and the preliminary emulsion temperature was higher. Tolerable maximum processing pressure at which phase inversion did not occur was called “critical processing pressure.”The data of this study were subjected to statistical evaluation and indicated that the first- and second-order term of oil phase volume and the first-order term of preliminary emulsion temperature significantly affected “critical processing pressure.” Moreover, the observation equation was introduced by the method of least squares, as follows: P=6.53V2-1100V-17T+47350 where P is the critical processing pressure (psi), V is the oil phase volume (in %), and T is the preliminary emulsion temperature (°C). The possibility that the hydrodynamic cavitation might be a significant factor in phase inversion was discussed.

Prediction of Stability in Pharmaceutical Preparations VIII: Oil-in-Water Emulsion Stability and the Analytical Ultracentrifuge

An oil-in-water emulsion clears in a centrifugal field to form a packed, semirigid “cream.” Subsequently, a true oil or continuous phase is spun-out of the “cream.” It is shown that rates of emulsion clearing can be stated as a function of the ultra-centrifugal r.p.m. and that the rate of clearing under simple gravity can be predicted for the oil-water emulsion as initially constituted. “Bad” emulsion can be differentiated from “good” emulsion by the ready formation of a separate oil phase in the former. In the latter case, an induction period exists before a continuous oil phase is spun out at an accelerating rate, which rate is a function of the centrifugal force.