Hydrocarbon production system and method of use

Abstract

The method of the present invention employs a subsurface production pump to displace hydrocarbon fluid, including any and all accompanying ground water and / or earthen contaminants, from the subterranean hydrocarbon reservoir depth of an oil well to surface storage and handling facilities via the subsurface production tubing, wellhead and surface flow line. As the subsurface production pump operates, compressed gas, or a mixture of compressed gases of sufficient volume and force is fed into the lower end of the subsurface production tubing in proximity to, or at a point above the subsurface production pump to mix into the hydrocarbon production fluid column. The resultant and considerably reduced density of the subsurface hydrocarbon production fluid column provides a reduction of subsurface production pump loading with all types of subsurface production pumps, and an improvement of sucker rod fall time when sucker rod activated subsurface plunger pumps are employed. Due to the additional cubic volume of the injected compressed gas, the increased hydrocarbon production fluid and gas velocity within the subsurface production tubing and the surface flow line improves hydrocarbon fluid shear from the conduit walls and sucker rod surfaces, and prevents earthen contaminants such as sand, clay, shale, coal or other rock fragments, from precipitating, accumulating and blocking the flow of hydrocarbon production fluid within the subsurface production tubing and the surface flow line.

Description

BACKGROUND OF THE INVENTION[0001]The purpose of the present invention is to provide an improved method and an improved apparatus to displace light, medium, heavy or very viscose hydrocarbon fluid which may be contaminated with earthen solids and water, from a subterranean hydrocarbon reservoir to a hydrocarbon production fluid storage tank or other handling facilities on ground surface, by means of oil well production, especially in oil wells wherein currently used hydrocarbon production systems are mechanically incapable of sustained or economic production.[0002]The method of the present invention employs a subsurface production pump to displace hydrocarbon fluid, including any and all accompanying ground water and / or earthen contaminants, from the subterranean hydrocarbon reservoir depth of an oil well to surface storage and handling facilities via the subsurface production tubing, wellhead and surface flow line. As the subsurface production pump operates, compressed gas, or a mix...

AI Technical Summary

Benefits of technology

[0015]feeding compressed gas of sufficient volume and pressure from a source at surface, by conduit means, into and through the wellhead, into and through the subsurface compressed gas feed tubing string, into and through the compressed gas communication port, into and through the subsurface hydrocarbon production tubing string, through the wellhead, into and through the surface flow line, and into the hydrocarbon production fluid storage tank or other handling facility(s) at surface; mixing compressed gas, hydrocarbon fluid and it's contaminants within the subsurface hydrocarbon production tubing string; permitting the compressed gas to decompress within the subsurface hydrocarbon production tubing string and surface flow line; providing a means to separate produced hydrocarbon fluid and gas at surface; venting gas from within the hydrocarbon production fluid storage tank or other handling facility(s) at surface; providing means to recover hydrocarbon fluid and contaminants from the hydrocarbon production storage tank or other handling facility(s) at surface; continuing the production cycle.

[0018]As the compressed gas is fed into the lower end of the subsurface hydrocarbon production tubing string at a point preferably, but not necessarily, located just above the operating subsurface production pump, the preferably continuous feed of compressed gas is mixed and combined with hydrocarbon production fluid. As the mixture advances upwards to the surface storage facility(s) at an accelerated fluid velocity due to the additional volume of injected gas, the gas decompresses proportionally, throughout the entire subsurface hydrocarbon production fluid column, resulting in a subsurface hydrocarbon production fluid column of much lighter weight or density above the subsurface production pump, the advantages being a considerably reduced load on the subsurface production pump, reduced mechanical strain and wear on all components throughout the entire pumping apparatus, and an increased hydrocarbon production fluid velocity within the subsurface hydrocarbon production tubing string and surface flow line. The higher fluid velocity improves viscose fluid flow properties through conduits and improves the fluid flow entrainment of solids though conduits. If sucker rod driven subsurface plunger pumps are used, sucker rod fall time is very much reduced due the much reduced density of the hydrocarbon production fluid column, and less horsepower is required to lift the sucker rods during the upstroke. If sucker rod driven progressing cavity pumps are used, considerably less horse power is required to drive the sucker rod string due to the reduced work load on the progressing cavity pump, and there will be a considerable reduction of hydrocarbon fluid drag on the rotating sucker rods.

[0019]The minimal or optimal mechanical effects and advantages achieved by the method of the present invention may be calculated by, and are dependant upon the volume of compressed gas being fed into the lower end of the subsurface hydrocarbon production tubing string. By sufficiently increasing the volume of compressed gas being fed into the lower end of the subsurface hydrocarbon production tubing string at a point in proximity to, or above the subsurface production pump, the subsurface production pump output of hydrocarbon fluid and earthen contaminants combine with, and become part of, the resulting high velocity hydrocarbon fluid and gas stream flowing through the subsurface hydrocarbon production tubing string, through the wellhead, into and through the surface flow line and into the hydrocarbon production storage tank or other handling facility(s) at surface. When thus displacing the hydrocarbon fluid and it's contaminants from the output end the subsurface production pump to surface storage, all components of this hydrocarbon production pumping method and apparatus operate within a state of it's best mechanical efficiency. Herein, less horsepower is required, less equipment stress and wear is present, and the subsurface production pump operates at maximum efficiency with minimal effort and wear.

[0023]In cases where two or more oil wells are closely positioned, as on a pad with multiple oil wells, one gas compressor of sufficient capacity may be very efficiently used to supply the compressed gas feed for two or more oil wells. With the subsurface production pump of each oil well operating continuously, the one gas compressor of sufficient capacity may inject sufficient amounts of compressed gas into the lower ends of two or more subsurface hydrocarbon production fluid columns intermittently to achieve the desired effect(s) within each oil well. A programmable valve controller or other means may be used to open and close valves as required to repetitively cycle compressed gas to each of the oil wells as required. Alternatively, the gas compressor may feed two or more oil wells simultaneously by employing compressed gas flow dividers or other means to direct accurate volumes of compressed gas to each oil well.

[0025]The preferred choice of subsurface production pump for the method of the present invention is the tubing liner plunger pump. By comparison, it is much less expensive, much more durable, has a greatly extended service life, and may be used for cold primary or thermally stimulated production. If progressing cavity pumps are used, the number of progressing cavity stages should be reduced in order to make the passing of earthen solids less damaging to the rotors and stators.

Problems solved by technology

Subterranean hydrocarbon reservoir characteristics and hydrocarbon fluid characteristics, may present problems wherein continuous or more economical hydrocarbon production is difficult or not possible while employing current production systems including subsurface sucker rod driven plunger pumps and progressive cavity pumps or other types of subsurface production pumps.

Reduced daily production is thereby unavoidable.

If the light or viscose hydrocarbon fluid being produced contains considerable amounts of earthen particulates, the earthen particulates may accumulate and cause fluid blockages within the subsurface production tubing and surface flow line.

When the accumulation of earthen particulates becomes too great, the sucker rods simply will not fall, or will not fall at an acceptable fall rate, through the column of hydrocarbon fluid and earthen materials, and production thereby fails, and well servicing is required.

The earthen particulates also cause extreme abrasion of the sucker rods and production tubing and premature failure of each, which eventually will require replacement of each.

Sucker rod and production tubing abrasion, wear and mechanical stress is greatly increased in oil wells that have high pumping pressures and / or deviations off the vertical line due to drilling problems, or in slant, whip stocked or horizontal well bores.

These pumps inherit all the problems associated with sucker rod use, are quickly destroyed when the well bore fluid is pumped off, or the rotors and stators will be badly damaged when pumping rock fragments or pyrite balls or sand or sand slugs.

They have a much shortened life and a much reduced efficiency when pumping high fluid pressures and / or high fluid temperatures.

They also have a much shortened life when pumping high amounts of earthen particulates, especially water sand and rock fragments.

Within many oil sands production wells, seizure of the sucker rods by accumulations of earthen particulates packed within the subsurface production tubing string is a never ending problem that may occur daily.

Electrically driven submersible progressing cavity pumps enjoy some use in the effort to eliminate friction and abrasion caused sucker rod and production tubing wear, but are still prone to the other limitations of progressing cavity pumps.

Frequent replacement of subsurface components due to excessive metal to metal wear, especially in the presence of abrasive produced earthen particulates, presents considerable replacement cost in addition to the economic loss of sales revenue due to oil well down time.

A percentage of such oil wells present ongoing problems that seem unsolvable.

After spending substantial amounts of time, money and fruitless effort, such oil wells are sooner or later considered to be mechanically or economically not viable, and are usually sold or abandoned.

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