Showing papers on "Steam injection published in 1971"

Steam injection in gas turbines having fixed geometry components

Abstract: Control means are provided for utilizing maximum tolerable amounts of steam in gas turbines having fixed geometry components under various operating conditions Optional means include: means for automatically holding a constant cycle pressure ratio under all ambient conditions; temperature sensing control means for automatically adjusting steam injection in both low and high temperature ambients to avoid visible plumes and to avoid acid condensation, respectively; or combined temperature and humidity sensing control means for automatically optimizing steam injection under all conditions of ambient temperature and humidity

Steam drive oil recovery process

Abstract: A line drive steam injection process in a dipping formation is improved by injecting steam into a row of up-dip wells and producing oil from two or more rows of down-dip wells. After steam breaks through into the first row of down-dip producing wells, steam injection is stopped in the up-dip wells and steam injection is initiated in the row of down-dip wells into which steam has broken through. Simultaneously, a non-condensing gas is injected into the up-dip wells to prevent upward migration into the segment of the formation contacted by steam injected through the original up-dip injectors of steam injected into the new row of down-dip injectors.

Steam distillation drive--Brea Field, California

Abstract: In the displacement of a volatile oil by steam, the lighter fractions of the residual oil are vaporized by steam distillation. These volatile fractions condense as they come in contact with the colder formation, forming a solvent or miscible bank ahead of the steam front. Laboratory experiments have demonstrated that very low residual oil saturations (depending upon the oil volatility) are possible with a steam-distillation drive. This process has been field tested in a steeply dipping reservoir containing 24$ API gravity oil at a depth of 4,600 ft. Results from this pilot indicate that the steam drive was very stable showing little tendency for early breakthrough to downdip production wells. Residual oil saturations of 8% and less were obtained and the average produced oil gravity was increased by the light components distilled from the oil remaining in the steam zone. A relatively low air permeability (for steam driving) of 70 md necessitated the use of 2,000 psi steam to inject 500 to 1,000 bpd water, as steam. This injection pressure combined with the 4,600-ft well depths necessitated the use of insulated tubing to attain bottom-hole steam qualities greater than 50%. Several injection well and insulated tubing designs were tested.

Method for recovering oil from subterranean reservoirs

Abstract: A method for recovering oil from a subterranean oil reservoir which has a finite water saturation and is deficient in energy so that it will not flow by natural means, whereby, first, steam is injected into the reservoir at a faster volumetric rate than production is taken from the reservoir in order to raise the pressure and temperature of the reservoir and then injection is ceased and production of the oil is commenced so that the pressure of the reservoir drops at least to the flash point of the water in the reservoir. Then continuing to produce oil from the reservoir.

Control of a steam zone

Abstract: In a rising steam flood thermal recovery process wherein viscous crude oil is recovered from a subsurface earth formation which comprises an upper predominately oil saturated zone and a lower predominately water saturated zone by injecting hot water and/or steam into the lower predominately water saturated zone through an injection well and producing fluids from the formation through a production well, a method for controlling the movement of steam within the formation by selectively plugging back the injection and producing wells.

Oil vaporization during steamflooding

Abstract: A procedure was developed for calculating the amount of oil vaporized or distilled in the steam zone during steamflooding of an oil reservoir. Results are intended to be used with other techniques for calculating oil recovery during steamflooding. Two experiments were conducted in which steam was injected into an oil-saturated, sand-packed tube to investigate oil vaporization by steam. In these experiments, the amount of vaporization of oil by steam is directly related to the amount of steam contacting the immobile oil. Calculations presented indicate that oil vaporization during steamflooding increases as the volatility of the oil and as the steam temperature increases, but decreases as the steam-injection rates increase. Recoveries calculated by this procedure are conservative when compared with other laboratory experiments which included the effects of gas drive and solvent extraction. 10 fig., 8 tables.

Method for recovery of hydrocarbons utilizing steam injection

Abstract: A method of recovering hydrocarbons from a subterranean hydrocarbon-bearing formation wherein a mixture of steam and a minor amount of an interfacial tension reducer, such as quinoline, etc. is introduced into the formation and oil displaced through the formation is recovered through a production well. Preferably, the formation is heated prior to the introduction of the steam-interfacial tension reducer mixture.

Reduction of Nitrogen Oxides From Gas Turbines by Steam Injection

Abstract: This paper describes the results of tests to determine the effects of steam injection on the production of nitric oxide in gas turbine combustors. When the steam injected into the compressor discharge was 2 percent of the total air flow, the oxides of nitrogen were reduced to 50 percent of what they were with no steam injection for a given load in a gas fired machine. When the steam flow was increased to 4 percent the oxides of nitrogen dropped to 25 percent of the value with no steam.Copyright © 1971 by ASME

Oil Recovery by Hot-Water and Steam Injection

Abstract: Since the early fifties, hot-fluid injection methods to improve the production from heavy oil reservoirs have received considerable attention. Hot-water and steam drive were field-tested first, but development of these processes has been considerably delayed in favor of cyclic injection of steam. The latter is mainly a stimulation method limited to undepleted reservoirs. It is nevertheless responsible for most of the thermal oil produced today. Its attractiveness lies in the low risk factor, the low investment and the rapid pay-out in cases of success. However, careful engineering is necessary for successful operation. Simplified theoretical models have recently been published that may assist the selection of optimum operating conditions. In areas where cyclic steam injection has been fully developed, thermal drives are regaining attention for higher ultimate recoveries. A hot-water drive is cheaper to operate than a steam drive, but it is essentially an unstable process. Steam can, however, stably displace oil of several hundreds of centipoises (cp). Both processes can be studied in scaled laboratory experiments, while numerical simulators are under development. This will facilitiate the determination of optimum project design as more and more cyclic steam injection projects are converted to drives. (81 refs.)

A Two-Dimensional Analysis of Reservoir Heating by Steam Injection

Abstract: The widely used Marx and Langeheim solution for reservoir heating by steam injection fails to account for the growth of the hot liquid zone ahead of the steam zone. Furthermore, that solution does not consider radial heat conduction both within and outside the reservoir and vertical conduction within the reservoir. A solution is provided which eliminates the restrictive assumptions of the old theory. The partial difference equations which describe the condensation within the steam zone and temperature distribution within the system have been solved by finite difference schemes. Results show that heat losses from the reservoir into the surrounding rocks are not greatly different from those predicted by Marx and Langeheim. However, the heat distribution is markedly different. A sizable portion of the reservoir heat was contained in the hot liquid zone which grows indefinitely.

Oil recovery by a water-driven steam slug

Abstract: Results of an experimental study of oil recovery by a steam slug driven by a cold waterflood in a linear porous medium are described. The model included simulations of heat losses to the adjacent formations. Steam displacements were conducted, using a number of hydrocarbons and various steam-slug sizes, with the core initially containing a residual oil or irreducible water saturation. It was found that the steam-slug displacement is more efficient in the case of light oils than for the heavier ones. The injection of cold water following steam resulted in almost total condensation of the steam present in the porous medium, with the process degenerating into a hot waterflood. The oil recovery efficiency of the process depends on whether an oil bank is formed during the steam-injection phase and whether the oil responds favorably to a hot waterflood.

Production well steam injection lagging

Abstract: Steam is injected through a stainless steel string into the formation, to lower the viscosity of the oil and thus promote outward production. At the same time a solution of silicate is piped into the annular space between the string and the perforated hole casing so that the steam in the string heats and boils off the water from this silica solution, a thin even skin of foam forms on the outside of the string, thus conserving the heat and so the efficiency of the injected steam. Centering devices should be used to keep the string out of contact with the hole wall. Silica solution should have density 22-50 Be at 20 degrees C., with ratio between 1.3 : 1 and 1-5.0 : 1 in terms of silica to alkali metal oxide.

A Mathematical Model of Cyclic Steam Injection

Abstract: The planning of steam-soak projects involves a study of the effect on profitability of varying the parameters that characterize a project. Because the number of possible combinations of these technical and economic variables is almost unlimited, the development of a computer program is imperative. The new program enables one to study the performance of large-scale steam-soak projects. The wells of a project could be classified into a limited number of groups, each group comprising the wells with almost indentical steam-soak performance characteristics. A group thus has an average performance curve that represents the steam-soak performance of a single (typical) well. This is simulated with the aid of the mathematical model of a simplified steam soak well built into the program. Most of the pertinent parameters are fixed by well established physical conditions. A few of them are determined by the behavior of laboratory fluid flow models and/or that of actual steam-soak wells (mathematical-model calibration). The paper deals with the general features of the mathematical steam-soak well model and those of the program for planning steam-soak projects. Examples of mathematical-model calibration and steam-soak project optimization are also outlined.