Solids hydraulic fracturing

Benzene, 30 parts may be gelled by adding potassium tridecylxanthate 3 parts naphtha 30 parts will further stabilize (he gel. Possible uses are solid fuels, lubricants, military incendiaries 8t hydraulic fracturing fluids. Addition of w, 3—5%, will liquefy the gel... 

Hydraulic fracturing in conjunction with gravel packing (87-90) creates a short wide fracture that is packed with gravel (proppant) sized to prevent solids production. A high flow rate into the well can be maintained without solids production because fluid flows across the fracture face at rates below the critical solid production rate. 

Suspensions or slurries used for well stimulation are prepared by adding a known quantity of proppant to the carrier fluid of choice to obtain a desired proppant concentration. The proppant concentration is usually referred to as the amount of solids added in a gallon of carrier fluid. A 20-40 U.S. mesh size is the most commonly used proppant for hydraulic fracturing. However, other particle sizes such as 8-12, 8-16, 10-20, 12-20, and 40-60 mesh are also used. 

Polymer requirements are dictated by the specific application. In drilling, the polymers must be shear stable and provide a means of suspending and removing formation cuttings. For use in hydraulic fracturing, the polymeric fluid must also suspend solid proppants, help control fluid loss, reduce friction and provide viscosity for the creation of fracture width. However, after the treatment the polymer containing fluid must be degradable, so that it can be readily returned from the formation and not interfere with oil and gas production. 

With hydraulic fracturing, fracture conductivity is maintained by propping open a fracture created with a solid material, such as sand, bauxite, ceramic, and certain lighter-weight materials. When used in hydraulic fracturing, these materials are referred to as proppants. 

As mentioned in chapter 2, fracture acidizing is an alternative to hydraulic (propped) fracturing in carbonates. With fracture acidizing, fracture conductivity is achieved by using acid to etch the walls of the created fracture. With hydraulic fracturing, fracture conductivity is achieved by filling the fracture with solid proppant to hold it open. 

Width assumes a great importance when one realizes that to maintain conductivity through the induced fracture it is nearly mandatory that the crack be filled with a solid spacing agent (called proppant) which will prevent the crack from closing completely after the hydraulic pressure on the well is released. 

Radio frequency heating, 500 Steam stripping, 500 Vacuum extraction, 500 Aeration, 501 Bioremediation, 501 Soil flushing/washing, 502 Surfactant enhancements, 502 Cosolvents, 502 Electrokinetics, 503 Hydraulic and pneumatic fracturing, 503 Treatment walls, 505 Supercritical Water Oxidation, 507 Solid Solution Theory, 202 Solubility products, 48-53 Metal carbonates, 433-434 Metal hydroxides, 429-433 Metal sulfides, 437 Sorption, 167 See Adsorption Specific adsorption, 167 See Chemisorption Stem Layer, 152-154 Sulfate, 261... 

The black solid lines, denoted as FFL , are the fracture forming lines that were determined by means of tensile and bi-axial circular and elliptical hydraulic bulge tests (refer to Figure 8.5). The FFLs are bounded by grey areas corresponding to an interval of 10 per cent due to the experimental uncertainty in their determination. 

Low acid volumes should be used in poorly consolidated formations, low-permeability formations, and formations with high clay content. In poorly consolidated sands, excessive HF can cause sloughing or collapse of perforations and, possibly, sand production. Excessive HF in low-permeability formations and in formations with high clay content can cause severe plugging because of reprecipitation of dissolved solids. Formations with native permeability less than 10 mD can be acidized with care. However, hydraulic (propped) fracturing may often be the stimulation method of choice. 

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