Abstract:
The purpose of the method of the present invention is to provide an improved method and an improved apparatus, to displace light, medium, or viscous hydrocarbon fluid, which may be contaminated with earthen solids, from the subterranean hydrocarbon reservoir to a hydrocarbon fluid storage tank or other handling facilities on ground surface, by means of oil well production. The method is intended for use in cold primary hydrocarbon production or thermally stimulated hydrocarbon production from vertical, slant, whipstocked, or horizontal oil wells. The production system does not employ moving subsurface mechanical components.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The purpose of the method of the present invention is to provide an improved method and an improved apparatus, to displace light, medium, or viscous hydrocarbon fluid, which may be contaminated with earthen solids, from the subterranean hydrocarbon reservoir to a hydrocarbon fluid storage tank or other handling facilities on ground surface, by means of oil well production. The method is intended for use in cold primary hydrocarbon production or thermally stimulated hydrocarbon production from vertical, slant, whipstocked, or horizontal oil wells. The production system does not employ moving subsurface mechanical components. 
         [0002]    The method of the present invention provides a two stage subsurface production apparatus that is placed within the wellbore. Geophysical subterranean hydrocarbon reservoir pressure is utilized to force hydrocarbon fluid from the subterranean hydrocarbon reservoir, and into a subsurface hydrocarbon production tubing string. A stream of compressed gas supplied from a source at surface is fed into an upper second stage of the subsurface hydrocarbon production tubing string at an appropriate wellbore elevation. The stream of hydrocarbon fluid and the stream of compressed gas mix, combine, and decompress within the subsurface hydrocarbon production tubing string, to form a low pressure, very low density, high velocity hydrocarbon production stream, that entrains and carries all components of itself, through the subsurface hydrocarbon production tubing string, wellhead, surface flow line, and into the hydrocarbon production storage tank or other handling facilities at ground surface, by means of the gas pressure differential. 
       DESCRIPTION OF PRIOR ART 
       [0003]    Production of the more viscous hydrocarbon fluid being extracted from subterranean hydrocarbon reservoirs in North America and around the world is more expensive and time consuming than the production of lighter or less viscous hydrocarbon fluid. More pumping horsepower is required in cold primary hydrocarbon production due to the resistant fluid flow properties of the viscous hydrocarbon fluid flowing through the conduits, and the subsurface sucker rod driven plunger pumps must be operated at a slower speed, due to the additional time required for the sucker rods to fall through the viscous hydrocarbon fluid column, to the bottom of the plunger pump stroke. Use of progressing cavity pumps can provide an improvement of hydrocarbon production fluid volume in less time, but progressing cavity pumps have a short service life due to the high pumping pressure encountered when pumping the more viscous hydrocarbon fluid, and their use is limited to cold hydrocarbon fluid production and lesser pressures. 
         [0004]    When displacing any grade of light, medium or viscous hydrocarbon fluid from the subterranean depths of unconsolidated, or poorly consolidated oilsands reservoirs, or reservoirs yielding other types of solid earthen contaminants, by means of cold primary hydrocarbon production or thermally stimulated hydrocarbon production, the subsurface production pump, sometimes referred to as the bottom hole pump, pumps hydrocarbon fluid and any accompanying sands or rock fragments into the bottom end of, and up the subsurface hydrocarbon production tubing string, where, over time, the earthen solids precipitate from the rising fluid column and accumulate therein, until fluid blockages are formed, and hydrocarbon production is thereby terminated. When using bottom hole pumps, the rules of fluid mechanics define how long it will take for an oil well displacing a given quality of solids contaminated hydrocarbon fluid to develop fluid blockages. To illustrate, some oil well operators in the Canadian Oilsands often preform scheduled flushbys to prevent oil well shutdowns, due to expected sand blockages, at expected times. 
         [0005]    When producing light, medium, or viscous hydrocarbon fluid containing solid earthen contaminants such as sand, small rocks or rock fragments, the service life of subsurface production pumps, sucker rods and production tubing may be dramatically shortened, due to metal and stator material loss caused by friction and the grinding action of the earthen solids caught between moving metal components. 
         [0006]    Tail joints, sometimes referred to as pick-up joints, are often installed below subsurface reciprocating plunger pumps, progressing cavity pumps, or other pumps, in attempts to prevent gas locking, slowed production, or pump damage due to the passage of excessive volumes of natural gas through the subsurface production pumps. Within oil wells producing earthen solids, tail joints installed below the subsurface production pump tend to become plugged with earthen solids, and terminate hydrocarbon production. The earthen solids must be removed from the tail joint before hydrocarbon production can be restarted. In most cases, this requires the use of a service rig to remove the subsurface production tubing, pump and tail joint for cleaning at surface. 
         [0007]    In Canada, millions of barrels of heavy oil reserves are lost each year, as the subterranean hydrocarbon reservoirs are damaged and rendered economically non-producible, due to excessive hydrocarbon production rates that result in excessive or prohibitive water production, and/or solids production, and/or natural gas production. Excessive hydrocarbon production rates result in low wellbore fluid levels having insufficient hydrostatic fluid head pressure to regulate the expulsion of subterranean hydrocarbon reservoir materials. Under these conditions, water and/or natural gas find and create free-flowing passages for themselves through the reservoir and into the wellbore, in volumes that prohibit or retard hydrocarbon flow into the wellbore. In other cases, over-production of the subterranean hydrocarbon reservoir initiates loosening of greater amounts of earthen solids that are entrained and carried by the flow of hydrocarbon and/or water, into the wellbore, and into the production pumping apparatus. After the subterranean hydrocarbon reservoir is thus damaged, in some cases, excessive water production may be reversed to a degree, but in most cases, the damage cannot be repaired or reversed, and the oil wells are sold or abandoned. 
       SUMMARY OF THE INVENTION 
       [0008]    More particularly, In accordance with one aspect of this invention, there is provided a cased oil well, a pressurized subterranean hydrocarbon reservoir, and a hydrocarbon fluid storage tank or other handling facility at surface, the improvement comprising a subsurface hydrocarbon production tubing string adapted to receive hydrocarbon production fluid including water, natural gas and solid earthen contaminants, from the pressurized subterranean hydrocarbon reservoir, through the subsurface hydrocarbon production tubing string&#39;s lower open end, and a compressed gas communication port adapted to feed compressed gas into the subsurface hydrocarbon production tubing string, through a connection located at an appropriate elevation of the subsurface hydrocarbon production tubing string, and including; 
         [0009]    means to convey the pressurized subterranean hydrocarbon reservoir output into and through the lower open end of the subsurface hydrocarbon production tubing string, to a point above the elevation of the compressed gas communication port; 
         [0010]    means to feed compressed gas from a supply at surface, into and through the compressed gas communication port, at the hydrocarbon fluid altitude, or fluid level, to be maintained above the subterranean hydrocarbon reservoir of the oil well during hydrocarbon fluid production, and into the hydrocarbon fluid storage tank or other handling facility at surface; 
         [0011]    a hydrocarbon fluid storage tank or other handling facility at surface, for receiving the hydrocarbon production fluid output of the oil well, and for holding, separating, and disposing the spent compressed gas, natural gas, hydrocarbon fluid and contaminants. 
         [0012]    In another aspect of the present invention, there is provided an improvement in a method of displacing light, medium or viscous grades of hydrocarbon fluid, which may contain contaminants including earthen solids, water and natural gas, from the subterranean hydrocarbon reservoir to surface storage by means of oil well production, which method includes the steps of; 
         [0013]    measuring the subterranean hydrocarbon reservoir pressure, and determining the hydrocarbon fluid altitude, or fluid level, to be maintained above the subterranean hydrocarbon reservoir of the oil well during hydrocarbon fluid production; installing the compressed gas communication port at that elevation; 
         [0014]    permitting the natural or artificial reservoir pressure of the subterranean hydrocarbon reservoir, to pressurize it&#39;s output of hydrocarbon fluid through the casing perforations, lower wellbore, and into the lower open end of, and up into the subsurface hydrocarbon production tubing string, to a point above the elevation of the compressed gas communication port; 
         [0015]    feeding compressed gas from a source at surface, through the compressed gas communication port, into and through the subsurface hydrocarbon production tubing string, into and through the wellhead, into and through the surface flow line, and into the hydrocarbon fluid storage tank or other handling facilities at surface; permitting the hydrocarbon fluid, water, natural gas and solid contaminants, to mix and combine with the stream of compressed gas, within the subsurface hydrocarbon production tubing string; permitting the combined mixture to decompress within the subsurface hydrocarbon production tubing string, to form a low pressure, very low density, high velocity hydrocarbon production stream; 
         [0016]    permitting the hydrocarbon production stream to displace through the subsurface hydrocarbon production tubing string, wellhead, surface flow line, and into the very low pressure volume within the hydrocarbon fluid storage tank or other handling facilities at surface, by means of the gas pressure differential; venting or recovering gas from the hydrocarbon fluid storage tank or other handling facility on surface; continuing the production cycle; providing a means to separate hydrocarbon fluid and gas; providing means to recover hydrocarbon fluid and any contaminants from the hydrocarbon fluid storage tank or other handling facility at surface. 
         [0017]    In the present system and method, use is made of the fact that a subterranean hydrocarbon reservoir, having sufficient geophysical or artificial pressure, will pressurize a stream of hydrocarbon fluid, water, natural gas, and solid earthen contaminants, through the casing perforations, through the lower wellbore, and into and up through the lower open end of a subsurface hydrocarbon production tubing string of lower internal pressure. Use is also made of the fact that a stream of compressed gas of sufficient volume and pressure, can be employed to entrain and carry viscous fluid volumes, earthen particulates and rock fragments, at considerable velocities, through horizontal, vertical, or inclined conduits. 
         [0018]    When the stream of hydrocarbon fluid, natural gas, water and solids from the subterranean hydrocarbon reservoir, and the stream of compressed gas, having sufficient volume and pressure, meet within the subsurface hydrocarbon production tubing string, the hydrocarbon fluid, earthen contaminants, water, and combined decompressing gases, form a low pressure, very low density, high velocity hydrocarbon production stream, that is forced and displaced, by means of the gas pressure differential, through the subsurface hydrocarbon production tubing string, wellhead, surface flow line, and into the very low pressure volume of the hydrocarbon production storage tank or other handling facilities at ground surface. 
         [0019]    In practice, the method of the present invention utilizes geophysical subterranean hydrocarbon reservoir pressure, to pressurize a supply of it&#39;s hydrocarbon fluid, including water, natural gas and solid earthen contaminants, if any, into and through the lower subsurface hydrocarbon production tubing string, to create a hydrocarbon fluid column within the lower subsurface hydrocarbon production tubing string, wherein the hydrocarbon fluid head pressure may, if the oil well is not in production, equalize to the subterranean hydrocarbon reservoir pressure. During operation, compressed gas is fed through the compressed gas communication port, which is placed and connected at a calculated elevation, to the subsurface hydrocarbon production tubing string, to create and feed a stream of low density, high velocity gas through the subsurface hydrocarbon production tubing string, for the purpose of entraining and carrying the hydrocarbon production fluid and all components thereof, through the upper subsurface hydrocarbon production tubing string, into and through the wellhead, surface flow line, and into the hydrocarbon fluid storage tank or other handling facility at surface. 
         [0020]    When starting the hydrocarbon production system initially, or after a shutdown, the fluid column within the subsurface production tubing string will be higher than it is during normal operating periods. As the compressed gas is initially fed into the subsurface production tubing string, a small volume of production fluid will flow downwards until excessive head pressure is lost. The very low density, high velocity hydrocarbon production stream will then form. 
         [0021]    In carrying out the present invention, the placement and connection of the compressed gas communication port to the subsurface hydrocarbon production tubing string, is calculated to be low enough to permit the subterranean hydrocarbon reservoir pressure to force a satisfactory volume of daily hydrocarbon production fluid to flow from the subterranean hydrocarbon reservoir, and into the compressed gas communication port, and high enough to provide a hydrocarbon production fluid column, having sufficient head pressure over the subterranean hydrocarbon reservoir to prevent excessive or uncontrolled expulsion of natural gas, water, hydrocarbon fluid and solid contaminants from the subterranean hydrocarbon reservoir, during oil well operation. By this means, and with wellbore perforation shots called by a competent person, a governed, daily hydrocarbon fluid production rate may most usually be achieved over many production years. Of further benefit, oil wells producing from unconsolidated sand reservoirs, and maintaining a proper fluid level, cost less to operate, as they require fewer flushbys, fewer coiled tubing jobs, and fewer service rig work-overs. The compressed gas communication port may optionally include a check valve mechanism, but no real practical benefit would be gained by it&#39;s inclusion. 
         [0022]    When employing the upper wellbore as a conduit to feed compressed gas from the supply at surface, and into the subsurface hydrocarbon production tubing string, the considerable cubic volume of the upper wellbore acts as a dampener to level out subterranean hydrocarbon reservoir surging, gas pressure spikes or fluid hammer within the subsurface and surface conduits. If a smaller subsurface compressed gas delivery conduit is employed, it will provide less, but usually sufficient pressure spike dampening. If necessary, very high pressure variances that may occur due to subterranean hydrocarbon reservoir pressure surging, may be controlled or dampened by other means provided in the subsurface or at ground surface. 
         [0023]    A desired gas, mixture of gases, or any practical gas of convenience such as steam, natural gas, air or carbon dioxide, may be utilized. The greater amount of gas may optionally be removed from the hydrocarbon fluid as the hydrocarbon fluid is fed into the hydrocarbon fluid storage tank, by an optional gas separation conduit or other means. The gas separation conduit if used, preferably should have an inside diameter of sufficient size to conduct the hydrocarbon fluid, by gravity means, to a lower level of the hydrocarbon fluid storage tank without having excessive spillage of hydrocarbon fluid out the top of the gas separation conduit. In selecting the inside diameter of the gas separation conduit, consideration should be given to the hydrocarbon fluid&#39;s expected input volume and viscosity. 
         [0024]    The optional gas separation conduit, illustrated in  FIG. 6 , if used, additionally serves to place the flow of new contaminated hydrocarbon fluid into the preferred lower level of the hydrocarbon fluid storage tank, and to avoid fluid churning and storage tank vibration that may occur, if the surface flow line was placed to direct it&#39;s output of hydrocarbon fluid and gas directly into the lower level of the hydrocarbon fluid storage tank. Gas scrubbers, filters and other devices, may be installed into the hydrocarbon production system as desired to protect the environment, gas compressors and other devices from in-taking earthen particulates, water droplets, hydrocarbon globules or vapours, or to conform to regulatory board rules. 
         [0025]    When displacing hydrocarbon fluid from a horizontal wellbore, the lower end of the subsurface hydrocarbon production tubing string may be constructed of an oil field grade of coiled tubing, to more easily pass through the dog-legged section of the wellbore and into the horizontal section of the wellbore, as illustrated in  FIGS. 2 and 3 . When displacing hydrocarbon fluid, including earthen solids, natural gas and water from a horizontal oil well, the horizontal and inclined segment of the subsurface hydrocarbon production tubing string is preferably sized therein, to provide a hydrocarbon fluid velocity sufficient to prevent the terminal settling and accumulation of solids therein. This velocity may not be possible when dealing with oil wells outputing very low production fluid and natural gas volumes. 
         [0026]    Within the method of the present invention, that portion of the subsurface production tubing located below the compressed gas communication port, may appear in some ways, to be similar to the tail joint employed below the subsurface production pumps of to-day&#39;s more conventional hydrocarbon production systems. Within the method of the present invention, use of the annular casing packer to direct the pressurized output of all components of the subterranean hydrocarbon reservoir, including hydrocarbon fluid, water, earthen solids and significant natural gas volume, provides an increased velocity of the subterranean hydrocarbon reservoir output through that portion of the subsurface production tubing located below the compressed gas communication port, to prevent solids accumulations and blockages therein. 
         [0027]    In cases were the light, medium, or viscous hydrocarbon fluid being produced does not contain sufficient volumes of earthen solids to merit concern of accumulations occurring within the wellbore, the subsurface hydrocarbon production tubing string may be installed to a wellbore depth not much greater than that of the compressed gas communication port that is installed on the subsurface hydrocarbon production tubing string, as illustrated in  FIG. 4 . Use of the annular casing packer is preferred, but not essential in all installations. 
         [0028]    The subsurface production tubing string requires a suitably sized inside diameter, considering the volume of gas, hydrocarbon fluid and contaminants to be carried to surface storage. The amount of compressed gas fed into the compressed gas communication port must be of sufficient, but not excessive volume and pressure to entrain and carry the hydrocarbon fluid and contaminants to surface storage. If the supplied compressed gas volume is excessive beyond a practical degree, or there are conduit related restrictions on the production side, more horsepower will be required to achieve production, and the production rate may be retarded, due to the excessive pressure build-up within the subsurface production tubing string, as it counters the subterranean hydrocarbon reservoir pressure and it&#39;s fluid output. 
         [0029]    There are several preferred mechanical apparatus assemblies from which to model an installation of the method of the present invention within an oil well. When operating the method of the present invention constructed as illustrated in  FIG. 2 , compressed gas is fed through the casing valve, into and through the wellbore, and into and through the compressed gas communication port. The annular casing packer serves to isolate the upper wellbore from the lower wellbore, in order to positively to direct the pressurized subterranean hydrocarbon reservoir output directly into the lower open end of the subsurface production tubing string. The annular casing packer also serves to secure and stabilize the lower end of the subsurface production tubing string within the wellbore. This equipment assembly, as described herein, and illustrated in  FIG. 2 , may not be possible to construct within in all oil wells, due to suspect casing integrity, regulatory board rules, or other issues. Use of the annular casing packer is preferred, as it also prevents solids accumulations from forming in the wellbore above the annular casing packer&#39;s position, but it&#39;s use not usually an essential requirement. 
         [0030]    When operating the method of the present invention, constructed as illustrated in  FIG. 3 , compressed gas is fed through the compressed gas communication port and into the subsurface production tubing string, with the aid of a subsurface compressed gas feed tubing string. A connection of the lower end of the subsurface compressed gas feed tubing string to the subsurface production tubing string serves as a conduit seal, and serves as a conduit vibration dampener and stabilizer. In some cases, personal choice or available equipment considerations, may lead to installing the subsurface compressed gas feed tubing string and the subsurface hydrocarbon production tubing string parallel to each other within the wellbore. Employment of the annular casing packer is preferred in this installation, but not necessarily required. 
         [0031]    When operating the method of the present invention, as constructed and described in the illustration of  FIG. 3 , the process of displacing hydrocarbon fluid and contaminants from the subterranean hydrocarbon reservoir to surface storage or other handling facilities, remains identical to the process of hydrocarbon fluid and contaminant displacement as constructed and described in the illustration of  FIG. 2 . The illustrated assembly differences illustrate flexibility of preferred or alternate equipment usage, to more easily adapt the method of the present invention to oil wells having differing designs or existing equipment, or to provide adaptability to conform to regulatory board rules, or other issues. 
         [0032]    When operating the method of the present invention, as constructed and described in the illustration of  FIG. 4 , the process of displacing hydrocarbon fluid from the subterranean hydrocarbon reservoir to surface storage or other handling facilities, remains identical to the process of hydrocarbon fluid and contaminant displacement as constructed and described in the illustration of  FIG. 2 . The illustrated assembly differences again illustrate flexibility of preferred or alternate equipment usage, or would be less expensively installed within oil wells producing light, medium or viscous hydrocarbon fluid that is not expected to contain considerable amounts of solid earthen contaminants that could accumulate and plug the lower wellbore. If the annular casing packer is not used, the lower open end of the subsurface production tubing string should be used as the compressed gas communication port. 
         [0033]    When operating the method of the present invention, as constructed and described in the illustration of  FIG. 5 , the process of displacing hydrocarbon fluid from the subterranean hydrocarbon reservoir to surface storage or other handling facilities, remains identical to the process of hydrocarbon fluid and contaminant displacement as constructed and described in the illustration of  FIG. 2 . The illustrated assembly differences illustrate flexibility of preferred or alternate equipment usage, within oil wells producing light, medium or viscous hydrocarbon fluid, that may be expected to contain very considerable amounts of solid earthen contaminants, that could accumulate and plug the lower wellbore. In the case of this assembly, the annular casing packer is essential to isolate the lower wellbore from the upper wellbore, and it further serves as a hanger to suspend the pickup tubing string within the lower wellbore. Use of tubing string stabilizers  17 B and  17 C, are preferred, and are designed to permit the flow of hydrocarbon fluid, solid contaminants, water and natural gas, upwards or downwards, within the wellbore. 
         [0034]    Proper sizing of the inside diameter of the pickup tubing string is essential to ensure that the subterranean hydrocarbon reservoir&#39;s volumetric output of solids contaminated hydrocarbon fluid, water, and natural gas, is pressurized and forced up through the pickup tubing string, at a velocity that is sufficient to entrain and carry all solid contaminants, through the pickup tubing string, and into the wellbore above the annular casing packer. In this assembly, the open lower end of subsurface production tubing string  12  serves as the intake for hydrocarbon fluid  13 , and as the compressed gas communication port  18 . 
         [0035]    In the case of solid contaminant build-up within wellbore  9 A, pickup tubing string  12 A, or subsurface production tubing string  12 , bull plug  6 A may be removed to allow the insertion of a small diameter tubing string to remove the solid contaminant build-up. It may also be employed to inject remedial treating chemicals into the lower wellbore and subterranean hydrocarbon reservoir. The same treatments may be accomplished by the same means within all other subsurface assemblies of the present invention. With some assemblies, the surface flow line may have to be disconnected to preform the small diameter tubing insertion, depending on the wellhead design. 
         [0036]    Bull plug  6 A may also be removed to allow the insertion of a small diameter tubing string or wire-line, to insert small diameter tools into and through the subsurface production tubing string and lower wellbore. Such usage may include tools to check equipment depth settings, subsurface production tubing integrity, lower casing integrity, logging tools, solids build-up in the lower wellbore, and other usage. 
         [0037]    When installing the method of the present invention as illustrated in  FIGS. 2 ,  3 , and  4 , and the annular casing packer is not installed, it is advisable to install tubing stabilizers to prevent vibration of the tubing and the subsequent tubing wear against the casing wall. 
         [0038]    A compressed gas flow reversing device,  19 , as illustrated in  FIG. 7 , and installed in subsurface equipment assemblies similar to those illustrated in  FIG. 2 ,  FIG. 3 ,  FIG. 4 , and  FIG. 5 , may be employed to reduce compressed gas feed pressure against the subterranean hydrocarbon reservoir output, by reversing the feed of compressed gas upwards, before the compressed gas is fed into the subsurface hydrocarbon production tubing string. The device is most beneficial in reducing long term abrasion and erosion of the inner subsurface hydrocarbon production tubing wall, at the point of compressed gas entry. The gas reversing device replaces compressed gas communication port  18 , and is effective when the preferred annular casing packer is employed. 
         [0039]    As the hydrocarbon production stream departs from the mixing area within the reversing device, a gas boundary layer is created against the inner walls of subsurface production tubing string  12  and surface flow line  21 , and the hydrocarbon production stream forms into a state of core annular flow, wherein the hydrocarbon globules, water droplets, and earthen solids, are forced to the centre of the hydrocarbon production stream  13 A, and carried therein, to the surface storage tank, protecting the production conduits from abrasion by earthen solids. This is useful to remember when constructing surface flow line directional changes, using long radii. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0040]    Having thus generally described the invention, reference will now be made to the accompanying drawings illustrating preferred embodiments in which; 
           [0041]      FIG. 1  is a schematic illustration of a typical prior art system to displace hydrocarbon fluid from a subterranean hydrocarbon reservoir to surface storage or handling facilities; and 
           [0042]      FIG. 2  is a schematic illustration outlining the method of the present invention to displace hydrocarbon fluid from a subterranean hydrocarbon reservoir to surface storage or handling facilities; and 
           [0043]      FIG. 3  is a schematic illustration outlining the method of the present invention employing an alternate equipment assembly. 
           [0044]      FIG. 4  is a schematic illustration outlining the method of the present invention employing an alternate equipment assembly. 
           [0045]      FIG. 5  is a schematic illustration outlining the method of the present invention employing an alternate equipment assembly. 
           [0046]      FIG. 6  illustrates a method to separate gas from hydrocarbon fluid. 
           [0047]      FIG. 7  illustrates a method to reduce compressed gas feed pressure against the subterranean hydrocarbon reservoir and reduce tubing abrasion. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0048]    Referring initially to  FIG. 1 , a typical oil well system includes a production casing indicated by reference numeral  8  which is placed into the earth. Within the casing  8  there is provided a subsurface production tubing string  12  which is basically a length or lengths of conduit coupled together from wellhead  6  to subsurface production pump  15 . The system also includes what is commonly known as sucker rods  10 . In use, hydrocarbon fluid  13  is fed by means of subterranean hydrocarbon reservoir  16  pressure into wellbore  9  through casing perforations  14  and pumped from wellbore  9  by subsurface production pump  15 , into and through production tubing  12 , into and through wellhead  6 , into and through surface flow line  21 , through optional surface check valve  20  and into hydrocarbon fluid storage tank  22 . Valve  7  is provided to vent casing gas. Optional surface check valve  20  is provided to prevent stored hydrocarbon fluid  13  from back-flowing from hydrocarbon fluid storage tank  22  into subsurface production tubing string  12 . Vent  23  is provided to vent gas from storage tank  22 . The sucker rod drive at surface is not shown. 
         [0049]    According to the present invention, as illustrated in  FIG. 2 , the oil well production system is modified to displace light, medium or viscous hydrocarbon fluid and contaminants including earthen solids, water and natural gas, from an oil well&#39;s subterranean hydrocarbon reservoir, to a hydrocarbon fluid storage tank or other handling facilities at surface, by means of vertical, slanted, whipstocked or horizontal oil wells, by following the steps of; 
         [0050]    measuring the subterranean hydrocarbon reservoir pressure and determining the appropriate wellbore elevation of the compressed gas communication port; 
         [0051]    suspending subsurface production tubing string  12  into wellbore  9 , with an upper connection to wellhead  6 , and extending the lower end to the subterranean hydrocarbon reservoir depth of wellbore  9 A; connecting compressed gas communication port  18  to subsurface production tubing string  12 , at the appropriate elevation; securing annular casing packer  17  to the lower end of subsurface production tubing string  12 ; securing annular casing packer  17 , within casing  8 ; isolating upper wellbore  9  from lower wellbore  9 A, by means of annular casing packer  17 ; 
         [0052]    providing surface flow line  21 , with a fluid communication connection at one end, to the output end of subsurface production tubing string  12 , through wellhead  6 , and a connection at the other end to dispose hydrocarbon production stream  13 A, into the hydrocarbon fluid storage tank  22 , or other handling facilities at surface; providing compressed gas delivery conduit  2 , with a connection at one end, to a supply of compressed gas  1 , and a connection at the other end to casing vent valve  7 ; 
         [0053]    providing optional compressed gas vent valve  4 , if desired, to a connection to compressed gas delivery conduit  2 ; providing optional surface check valve  20  if desired, with connections to surface flow line  21 ; providing optional compressed gas separation conduit  24 , if desired, within hydrocarbon fluid storage tank  22 ; extending surface flow line  21  to gap  25  above optional compressed gas separation conduit  24 , if used; 
         [0054]    permitting the sufficient pressure of subterranean hydrocarbon reservoir  16 , to pressurize hydrocarbon fluid  13  from subterranean hydrocarbon reservoir  16 , through casing perforations  14 , into and through lower wellbore  9 A, and into and through the lower open end of subsurface production tubing string  12 , and up to a point above the elevation of compressed gas communication port  18 ; closing optional compressed gas vent valve  4 , if installed; opening casing vent valve  7 ; feeding compressed gas  1  from a source at surface, into and through compressed gas delivery conduit  2 , into and through casing vent valve  7 , into and through upper wellbore  9 , into and through compressed gas communication port  18 , into and through subsurface production tubing string  12 , into and through wellhead  6 , into and through surface flow line  21 , and into hydrocarbon fluid storage tank  22 ; 
         [0055]    permitting the stream of hydrocarbon fluid  13  and the stream of compressed gas  1 , to mix, combine, and decompress within subsurface production tubing string  12 , to form a low pressure, very low density, high velocity hydrocarbon production stream  13 A; permitting hydrocarbon production stream  13 A, to flow, by means of the gas pressure differential, through the subsurface hydrocarbon production tubing string  12 , wellhead  6 , surface flow line  21 , and into the lower pressure zone of hydrocarbon fluid storage tank  22 , or other handling facilities at ground surface; permitting the increased velocity of hydrocarbon production stream  13 A, to entrain and carry all components of itself, through subsurface hydrocarbon production tubing string  12 , wellhead  6 , surface flow line  21 , and into the lower pressure zone within hydrocarbon production storage tank  22 , or other handling facilities at ground surface; 
         [0056]    optionally separating gas  1  from hydrocarbon production stream  13 A, by feeding hydrocarbon production stream  13 A from the extended output end of conduit  21 , through gap  25 , into the open top end of and through optional gas separation conduit  24 , if used; 
         [0057]    venting or recovering gas  1  from hydrocarbon fluid storage tank  22 , through storage tank gas vent  23 , to atmosphere or other gas handling facility; optionally preventing stored hydrocarbon fluid  13  from back-flowing from hydrocarbon fluid storage tank  22  and into subsurface production tubing string  12 , by means of optional surface check valve  20 ; continuing the hydrocarbon production system operation for a period of time; recovering hydrocarbon fluid  13  and contaminants, from hydrocarbon fluid storage tank  22 , or other handling facilities at surface. 
         [0058]    The schematic of  FIG. 3  illustrates the method of the present invention employing an alternate mechanical component assembly, to displace light, medium or viscous hydrocarbon fluid, which may contain contaminants including, earthen solids, water and natural gas, from an oil well&#39;s subterranean hydrocarbon reservoir, to a hydrocarbon fluid storage tank or other handling facilities at surface, by means of vertical, slanted, whipstocked or horizontal oil wells, by following the steps of; 
         [0059]    measuring the subterranean hydrocarbon reservoir pressure and determining the appropriate wellbore elevation of the compressed gas communication port; 
         [0060]    suspending subsurface compressed gas feed tubing string  11 , into wellbore  9 , with an upper connection to wellhead  6 , and a lower connection to conduit seal  17 A, at a near point below compressed gas communication port  18 ; 
         [0061]    suspending subsurface production tubing string  12 , equipped with the compressed gas communication port  18  installed at the appropriate elevation, concentrically into subsurface compressed gas feed tubing string  11 , with the upper end suspended through wellhead  6 , and the lower end extended to the subterranean hydrocarbon reservoir depth, and a connection below compressed gas communication port  18 , to subsurface compressed gas feed tubing string  11 , by means of conduit seal  17 A; securing annular casing packer  17 , to a lower point of subsurface production tubing string  12 , and to the inner wall of casing  8 ; 
         [0062]    providing surface flow line  21 , with a fluid communication connection at one end, to the subsurface production tubing string  12 , and a connection at the other end, to hydrocarbon fluid storage tank  22 , or other handling facility; 
         [0063]    providing compressed gas delivery conduit  2 , with a connection at one end to a supply of compressed gas  1 , and a connection at the other end to wellhead  6 ; 
         [0064]    providing optional compressed gas vent valve  4 , if desired, to a connection to compressed gas delivery conduit  2 ; providing optional surface check valve  20  if desired, with connections to surface flow line  21 ; providing optional compressed gas separation conduit  24 , if desired, within hydrocarbon fluid storage tank  22 ; extending surface flow line  21  to gap  25  above optional compressed gas separation conduit  24 , if used; isolating lower wellbore  9 A, by means of annular casing packer  17 , from upper wellbore  9 ; closing casing gas vent  7 ; 
         [0065]    permitting the sufficient pressure of subterranean hydrocarbon reservoir  16 , to pressurize hydrocarbon fluid  13 , from subterranean hydrocarbon reservoir  16 , through casing perforations  14 , into and through lower wellbore  9 A, and into and through the lower open end of subsurface production tubing string  12 , and up to a point above the elevation of compressed gas communication port  18 ; closing optional compressed gas vent valve  4 , if installed; 
         [0066]    feeding compressed gas  1  from a source at surface, into and through compressed gas delivery conduit  2 , into and through wellhead  6 , into and through subsurface compressed gas feed tubing string  11 , into and through compressed gas communication port  18 , into and through subsurface production tubing string  12 , and into and through surface flow line  21 , and into hydrocarbon fluid storage tank  22 , or other handling facilities at surface; 
         [0067]    permitting the stream of hydrocarbon fluid  13  and the stream of compressed gas  1 , to mix, combine, and decompress within subsurface production tubing string  12 , to form a low pressure, very low density, high velocity hydrocarbon production stream  13 A; permitting hydrocarbon production stream  13 A, to flow, by means of the gas pressure differential, through the subsurface hydrocarbon production tubing string  12 , surface flow line  21 , and into the lower pressure zone within hydrocarbon production storage tank  22 , or other handling facilities at ground surface; permitting the increased velocity of hydrocarbon production stream  13 A, to entrain and carry all components of itself, through subsurface hydrocarbon production tubing string  12 , surface flow line  21 , and into the lower pressure zone within hydrocarbon production storage tank  22 , or other handling facilities at ground surface; 
         [0068]    optionally separating gas  1  from hydrocarbon production stream  13 A, by feeding hydrocarbon production stream  13 A from the extended output end of conduit  21 , through gap  25 , into the open top end of and through optional gas separation conduit  24 , if used; 
         [0069]    venting or recovering gas  1  from hydrocarbon fluid storage tank  22 , through storage tank gas vent  23 , to atmosphere or other gas handling facility; optionally preventing stored hydrocarbon fluid  13  from back-flowing from hydrocarbon fluid storage tank  22  and into subsurface production tubing string  12 , by means of optional surface check valve  20 ; continuing the hydrocarbon production system operation for a period of time; recovering hydrocarbon fluid  13  and contaminants, from hydrocarbon fluid storage tank  22 , or other handling facilities at surface. 
         [0070]    According to the present invention, as illustrated in  FIG. 4 , the oil well production system is modified to displace light, medium or viscous hydrocarbon fluid and contaminants, including water and natural gas, from an oil well&#39;s subterranean hydrocarbon reservoir, to a hydrocarbon fluid storage tank or other handling facility at ground surface, by means of vertical, slanted, whipstocked or horizontal oil wells, by following the steps of; 
         [0071]    measuring the subterranean hydrocarbon reservoir pressure and determining the appropriate wellbore elevation of the compressed gas communication port; 
         [0072]    suspending subsurface production tubing string  12 , by means of an upper connection to wellhead  6 , and extending the lower end to the desired lower elevation within lower wellbore  9 A; connecting compressed gas communication port  18  to subsurface production tubing string  12 , at the appropriate elevation; connecting annular casing packer  17  to the lower end of subsurface production tubing string  12 ; securing annular casing packer  17 , within casing  8 ; isolating lower wellbore  9 A, by means of annular casing packer  17 , from upper wellbore  9 ; 
         [0073]    providing surface flow line  21 , with a fluid communication connection at one end to subsurface production tubing string  12 , and a connection at the other end to dispose hydrocarbon production stream  13 A, into the hydrocarbon fluid storage tank  22 , or other handling facilities at surface; providing compressed gas delivery conduit  2 , with a connection at one end, to a supply of compressed gas  1 , and a connection at the other end to casing vent valve  7 ; 
         [0074]    providing optional compressed gas vent valve  4 , if desired, to a connection to compressed gas delivery conduit  2 ; providing optional surface check valve  20  if desired, with connections to surface flow line  21 ; providing optional compressed gas separation conduit  24 , if desired, within hydrocarbon fluid storage tank  22 ; optionally extending surface flow line  21  to gap  25  above optional compressed gas separation conduit  24 , if used; 
         [0075]    permitting the sufficient pressure of subterranean hydrocarbon reservoir  16 , to pressurize hydrocarbon fluid  13  from subterranean hydrocarbon reservoir  16 , through casing perforations  14 , into and through lower wellbore  9 A, and into the lower open end of subsurface production tubing string  12 , and up to a point above the elevation of compressed gas communication port  18 ; closing optional compressed gas vent valve  4 , if installed; 
         [0076]    opening casing vent valve  7 ; feeding compressed gas  1  from a source at surface, into and through compressed gas delivery conduit  2 , into and through casing vent valve  7 , into and through upper wellbore  9 , into and through compressed gas communication port  18 , into and through subsurface production tubing string  12 , and into and through surface flow line  21 , and into hydrocarbon fluid storage tank  22 , or other handling facilities at surface; 
         [0077]    permitting the stream of hydrocarbon fluid  13  and the stream of compressed gas  1 , to mix, combine, and decompress within subsurface production tubing string  12 , to form a low pressure, very low density, high velocity hydrocarbon production stream  13 A; permitting hydrocarbon production stream  13 A, to flow, by means of the gas pressure differential, through the subsurface hydrocarbon production tubing string  12 , surface flow line  21 , and into the lower pressure zone of hydrocarbon production storage tank  22 , or other handling facilities at ground surface; permitting the increased velocity of hydrocarbon production stream  13 A, to entrain and carry all components of itself, through subsurface hydrocarbon production tubing string  12 , surface flow line  21 , and into the lower pressure zone within hydrocarbon production storage tank  22  or other handling facilities at ground surface; 
         [0078]    optionally separating gas  1  from hydrocarbon production stream  13 A, by feeding hydrocarbon production stream  13 A from the extended output end of conduit  21 , through gap  25 , into the open top end of and through optional gas separation conduit  24 , if used; 
         [0079]    venting or recovering gas  1  from hydrocarbon fluid storage tank  22 , through storage tank gas vent  23 , to atmosphere or other gas handling facility; 
         [0080]    optionally preventing stored hydrocarbon fluid  13  from back-flowing from hydrocarbon fluid storage tank  22  and into subsurface production tubing string  12 , by means of optional surface check valve  20 ; continuing the hydrocarbon production system operation for a period of time; recovering hydrocarbon fluid  13  and contaminants, from hydrocarbon fluid storage tank  22 . 
         [0081]    According to the present invention, as illustrated in  FIG. 5 , the oil well production system is modified to displace light, medium or viscous hydrocarbon fluid and contaminants including, earthen solids, water, and natural gas, from an oil well&#39;s subterranean hydrocarbon reservoir, to a hydrocarbon fluid storage tank or other handling facility at ground surface, by means of vertical, slanted, horizontal, or whipstocked oil wells, by following the steps of; 
         [0082]    measuring the subterranean hydrocarbon reservoir pressure and determining the appropriate wellbore elevation of the compressed gas communication port  18 ; 
         [0083]    securing annular casing packer  17 , within wellbore  9 , at a near point below the elevation of compressed gas communication port  18 ; isolating lower wellbore  9 A, by means of annular casing packer  17 , from upper wellbore  9 ; 
         [0084]    suspending pickup tubing string  12 A within wellbore  9 A, by means of an upper connection to annular casing packer  17 , and extending the lower end to the desired subterranean hydrocarbon reservoir elevation; securing tubing stabilizer  17 C, to the lower end of pickup tubing string  12 A, within wellbore  9 A; suspending subsurface production tubing string  12 , with an upper connection to wellhead  6 , and extending the lower end to a near point above annular casing packer  17 ; installing tubing stabilizer  17 B, to the lower end of subsurface production tubing string  12 ; 
         [0085]    employing the lower open end of subsurface production tubing string  12  as compressed gas communication port  18 , or providing a more abrasion resistant fitting; 
         [0086]    providing surface flow line  21 , with a fluid communication connection at one end to the subsurface production tubing string, through wellhead  6 , and a connection at the other end to hydrocarbon fluid storage tank  22 ; 
         [0087]    providing compressed gas delivery conduit  2 , with a connection at one end, to a supply of compressed gas  1 , and a connection at the other end to casing vent valve  7 ; 
         [0088]    providing optional compressed gas vent valve  4 , if desired, to a connection to compressed gas delivery conduit  2 ; providing optional surface check valve  20  if desired, with connections to surface flow line  21 ; providing optional compressed gas separation conduit  24 , if desired, within hydrocarbon fluid storage tank  22 ; extending surface flow line  21  to gap  25  above optional compressed gas separation conduit  24 , if used; installing bull plug  6 A into wellhead  6 ; 
         [0089]    permitting the sufficient pressure of subterranean hydrocarbon reservoir  16 , to pressurize hydrocarbon fluid  13 , from subterranean hydrocarbon reservoir  16 , through casing perforations  14 , into and through lower wellbore  9 A, and up into and through the lower open end of pickup tubing string  12 A, to a point above the elevation of compressed gas communication port  18 ; 
         [0090]    closing optional compressed gas vent valve  4 , if installed; opening casing vent valve  7 ; 
         [0091]    feeding compressed gas  1  from a source at surface, into and through compressed gas delivery conduit  2 , into and through casing vent valve  7 , into and through upper wellbore  9 , into and through compressed gas communication port  18 , into and through subsurface production tubing string  12 , into and through wellhead  6 , into and through surface flow line  21 , and into hydrocarbon fluid storage tank  22 , or other handling facilities at surface; 
         [0092]    permitting the stream of hydrocarbon fluid  13  and the stream of compressed gas  1 , to mix, combine, and decompress within subsurface production tubing string  12 , to form a low pressure, very low density, high velocity hydrocarbon production stream  13 A; permitting hydrocarbon production stream  13 A, to flow, by means of the gas pressure differential, through the subsurface production tubing string  12 , wellhead  6 , surface flow line  21 , and into the lower pressure zone of hydrocarbon production storage tank  22  or other handling facilities at ground surface; 
         [0093]    permitting the increased velocity of hydrocarbon production stream  13 A, to entrain and carry all components of itself, through subsurface hydrocarbon production tubing string  12 , wellhead  6 , surface flow line  21 , and into the lower pressure zone within hydrocarbon production storage tank  22  or other handling facilities at ground surface; 
         [0094]    optionally separating gas  1  from hydrocarbon production stream  13 A, by feeding hydrocarbon production stream  13 A, from the extended output end of conduit  21 , through gap  25 , into the open top end of and through optional gas separation conduit  24 , if used; 
         [0095]    venting or recovering gas  1  from hydrocarbon fluid storage tank  22 , through storage tank gas vent  23 , to atmosphere or other gas handling facility; optionally preventing stored hydrocarbon fluid  13  from back-flowing from hydrocarbon fluid storage tank  22 , and into subsurface production tubing string  12 , by means of optional surface check valve  20 ; continuing the hydrocarbon production system operation for a period of time; recovering hydrocarbon fluid  13  and contaminants from hydrocarbon fluid storage tank  22 , or other handling facilities at surface. 
         [0096]    According to the present invention, as illustrated in  FIG. 6 , gas is optionally separated from hydrocarbon production stream  13 A by following the steps of; 
         [0097]    providing optional gas separation conduit  24 ; placing optional gas separation conduit  24  vertically within hydrocarbon fluid storage tank  22 ; feeding hydrocarbon production stream  13 A from the output end of conduit  21 , downward into the open upper end of and through conduit  24 , into the lower level of hydrocarbon fluid storage tank  22 ; permitting the flow of gas exiting conduit  21  to escape by means of open gap  25  between conduit  21  and conduit  24 , into the upper level of the hydrocarbon fluid storage tank  22 ; venting gas from the upper level of hydrocarbon fluid storage tank  22  into and through storage tank vent  23  to atmosphere or other gas collecting or handling facility; providing conduit  24  with an inside diameter of sufficient size to conduct the hydrocarbon fluid, by gravity means, to a lower level of the hydrocarbon fluid storage tank  22 , without having excessive spillage of hydrocarbon fluid out the top of conduit  24 . 
         [0098]    According to the present invention, as illustrated in  FIG. 7 , compressed gas feed pressure against the subterranean hydrocarbon reservoir is reduced, and solids abrasion within the inner subsurface hydrocarbon production tubing wall, at the point of, and to a point above compressed gas entry, is reduced, by following the steps of; 
         [0099]    installing gas flow reversing device  19 , in the place of compressed gas communication port  18 ; feeding compressed gas  1  from a source at surface, into and through gas flow reversing device  19 , by means of compressed gas entry ports  19 B; 
         [0100]    permitting the subterranean hydrocarbon reservoir  16 , to pressurize it&#39;s output of hydrocarbon fluid  13 , including contaminants, into and through hydrocarbon production fluid port  19 C; 
         [0101]    permitting the stream of hydrocarbon fluid  13  and the stream of compressed gas  1 , to mix, combine, and decompress within gas flow reversing device  19 , to form a low pressure, very low density, high velocity hydrocarbon production stream  13 A; permitting hydrocarbon production stream  13 A, to flow, by means of the gas pressure differential, in a state of laminar flow, through port  19 D, and into and through subsurface production tubing string  12 , wellhead  6 , surface flow line  21 , and into the lower pressure zone of hydrocarbon production storage tank  22  or other handling facilities at ground surface.