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This paper deals with a new method of obtaining injection and producing well permeability profiles. The flow meter and nuclear fluid density tools and their use in analyzing reservoir behavior will be explained. Numerous logs obtained from secondary recovery projects and in producing wells for fracture evaluation and remedial planning will be discussed.

The present energy situation has required the oil industry to evaluate all feasible methods to sustain and increase production in order to keep pace with our energy needs. 'Lost production due to scale deposition has been a major problem in the oil industry and has plugged many a good well while reducing production in most others. Many different scale inhibition techniques exist today and all have varying degrees of success.

Long open-hole or heavily perforated intervals with stringers of varying porosities and permeability have always been difficult stimulation problems. In the majority of instances treatments have been staged, continuously, with various types of blocking agents. Only after the job was complete, could any down-hole evaluation of the success of the diverting agents be estimated. Obviously, critical information such as the extent of the formation treated per stage, communicated zones, channeling behind the pipe, etc. was unavailable until after the treatment was over.

Carbonate formations have been treated with acid for many years to increase fracture length and conductivity and, thereby, stimulate production. Fracture acidizing of carbonate formations, however, requires consideration of several parameters. One important parameter is the distance acid will penetrate the fracture before completely reacting. This distance is referred to as the acid penetration distance. Other parameters include dynamic fracture geometry and fracture conductivity.

The oil industry customarily has utilized various clay control additives to prevent formation damage caused by the hydration (swelling) or migration of clays. These additives include inorganic metal cations, (e.g. Zr+4, Al+3, Ti+4, et al.) synthetic polyacrylate polymer types, quaternary ammonium salts, and petroleum heavy ends. Clay stabilization using metal cations is accomplished by ion exchange with cations in the clay mineral lattice. These types of clay control agents are limited in application due to their general incompatibility with most polymers used to viscosify completion fluids.

Hydrochloric-Hydrofluoric acid mixtures for sandstone acidizing have been the topic of many investigations with respect to optimum hydrofluoric (HF) concentrations necessary for effective treatment. The hydrochloric acid (HCl) concentration needed is only at a concentration necessary to inhibit the formation of calcium fluoride (CaF2), and to provide a conversion media when utilizing ammonium bifluoride for HF production.

Based on the drift-flux model, a new mathematical formulation was developed to predict natural separation efficiency. The new model presented in this work considers the effect of the slip velocity in the radial direction, variable neglected in previous simplified models. In addition, a correlation for this effect was obtained by fitting the model to experimental data.

Use of 4-1/2 OD tubular in the completion of deep gas wells makes possible perforating a well with a large, non-expendable type fun while maintaining a pressure differential into the wellbore and treating the well at rates up to 50 BPM. Increases in a well's deliverability as a result of these techniques make the new design economically attractive. These completion methods can be performed on the well without the need to kill it either during or after completion of the well.

Historically, tight gas formations such as the Strawn limestone in Crockett County, Texas and the Devonian in Andrews and Midland Counties, Texas have been treated with pad and acid treatments consisting of gelled water, gelled acid and
crosslinked hydrochloric acid. A new emulsion polymer has been developed which significantly increases the efficiency of these treatments. The new emulsion polymer exhibits a polymer size approximately 15 times smaller than that previously known to the industry. The polymer also utilizes a highly specific external activator to initiate and promote hydration.

One of the primary concerns in completion practices for the Canyon Sand in Sterling, Schleicher, Sutton, and Crockett counties has been to balance possible formation damage with completion costs. The low productivity, and until very recently, the low gas prices for this area has made the use of "exotic" fracturing treatments very difficult to justify. The fluids were normally a gelled water or gelled weak acid system, often used with CO2. In those instances where the treatments are performed via tubing, low injection rates often contributed to screenouts.

A new friction reducer was tested in various fluids to measure its performance in both a small scale flow loop and a field scale system. The polymer was mixed into fresh water and a 1% KCl brine, then pumped through 1_ inch coiled tubing and straight pipe. Drag reduction as high as 69% was achieved in the coiled tubing, and as high as 84% in straight pipe. The study also included 7% KCl, 10 ppg NaCl and 11.4 ppg CaCl2. A small scale flow loop, consisting of _ inch diameter coiled tubing and straight pipe was used.

Fiberglass reinforced pipe (FRP) was originally developed and marketed in the oil field as a highly corrosion-resistant alternative to steel in relatively small-diameter, low-pressure gathering and flow lines. As the acceptance of FRP grew, so did the demand for larger diameters, and higher operating pressures.

In an everyday review of well and reservoir performance there is a wealth of interpretive tools such as the one given in SPE Monograph No. 1 on build-up interpretation and in many articles in the SPE journals. Too often, however, the meager data available for analysis causes concern as to the reliability of the conclusions. A typical problem involves the declining production rate of older wells, where the engineer is faced with the problem of determining what remedial steps, if any, can be justified. Several possible problems come to mind. 1. The pump may not be operating efficiently. 2.

In the recent National Petroleum Council (NPC) report to the Secretary of the Interior on the U.S. Energy Outlook", it is noted that naturally- occurring geothermal steam and hot-water reservoirs in California and Nevada, while potentially contributing up to only two percent of the total U.S. electrical generating capacity by the year 1985, could supply over one-third of the projected electrical power requirements for those two states (16,000 MW out of a total estimated requirement of 52,000 MW). The NPC projection, while close to a recent estimate by Dr.

Successful acid stimulation requires a method to distribute the acid between multiple hydrocarbon zones. Since almost all producing wells are inhomogeneous, containing sections of varying permeability, this can be a huge problem. In addition, the water saturation of the various zones plays an important role. Since acid is an aqueous fluid, it will tend to predominantly enter the zones with the highest water saturation. These water zones are also often the highest permeability zones, so acid stimulation will often result in large increases in water production.

Acid Polymer gels having pH less than one have been crosslinked for retarding the chemical and physical activity of hydrochloric acid on calcareous formations. Hydrochloric acid concentrations from & percent to 28 percent have been successfully crosslinked. This new and unique stimulation fluid offers high viscosity with adequate shear stability, perfect support for proppants and clay stabilization.

Lifting problems in producing wells can drastically cut the oil operator's profit on initial investment. Well conditions that cause severe lifting problems are: 1. High sand content in the producing fluid which will often damage or freeze the bottom hole pump. 2. Paraffin or gyp accumulation on the tubing I.D. and sucker rods, resulting in eventual plugging. 3. The oil produced is of low gravity and cannot be efficiently pumped in cold weather. Wells with the above conditions are presently being pumped with optimum efficiency through use of a new method of artificial lift.

Corrosion surveying of pipelines can now be performed by an instrumented pig which travels through the line with the fluid normally transmitted. A continuous log of the entire line shows the areas where corrosion pitting has occurred.

This paper will discuss the properties and applications of a new water-base fracturing fluid. In particular, it will discuss its leak-off characteristics, its rheological behavior, and its proppant-transport capability. Additionally, it will give examples of its use in the field, including production information. Beginning in the late 1960"s, intensive research was done in the area of improved stimulation fluids. This led to the development of a variety of crosslinked fracturing fluids based on both organic and synthetic polymers.

The use of a fluid containing an abrasive for perforating casing and cleaning open hole has been an established technique for many years. Generally, the jetting tool is installed on tubing along with a collar locator, tubing hold-down, centralizer, and in some instances an anchor swivel. The tool is then lowered to the desired perforating or jetting depth to be cleaned.

"Conventional acidizing has ignored relative permeability effects by attempting to inject aqueous fluids into zones filled with crude." Since most oil wells in the Permian Basin today are on water flood or produce large quantities of water, relative permeability is an issue. Therefore in zones where the water saturation is high due to depletion of the higher permeability zones and/or natural fractures, acid tends to enter these zones instead of the oil zones where the acid is needed and wanted. This in turn leads to higher water cuts instead of increased oil cuts.

A new technology now exists to expand solid stainless steel tubulars for downhole remedial pre frac applications. Very different from other expandable technologies, mainly due to the setting process and the capacity of the tools to expand until they're in contact with the casing, this technology has now been used successfully in several countries as a precision intervention to resolve a variety of downhole problems.

Delivery of recovered hydrocarbons from oil fields to refinery, storage and consumption points is related to significant oil products loss. Losses occure all the way from oil production up to receiving them by consumers. The losses are due to outfow, evaporation, weather factors, equipment imperfections, etc. However, according to the case studies, approximately 75% of liquid oil products losses are due to evaporations. Hydrocarbons evaporation is concerned with not only material losses, but also causes environment polluction by toxic hydrocarbons.

The sucker rod connection poses several problems to rig crews as well as the oil companies. The first issue the crews have to deal with is the face that there are two elements to a rod connection: The lower and the upper rod interfaces. Making up both elements to precise circumferential displacements at the same time is almost impossible.
This paper will deal with these issues and will illustrate a new tool that solves the makeup problems and at the same time, gives the crews a method to remove or replace a coupling.

A new treating method has been designed for use in wells in which injectivity has been decreased by deposition of polymer residue incurred in polyacrylamide polymer and copolymer treatments. This treatment consists of one or two stages: an oxidizer stage followed by an acid stage, or a combined acid-oxidizer stage. This treatment is effective against polyacrylamide polymer and copolymer deposits near the wellbore that will not respond to conventional treatments. It is known that polymer injection can gradually lead to a decrease in injectivity.