Well-Drilling Fluids

Well-drilling fluids perform a variety of functions such as  

Attapulgite clay is also used as a rheology modifier in drilling mud, and the addition of small quantities (approximately 2% by weight) of light-bum MgO helps to increase fluid viscosity. 

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Oilfield Uses. Calcium chloride has two uses in the oilfield as a primary ingredient in completion fluids and as the brine phase in an invert emulsion oil mud. An excellent review of oil well drilling fluids is available (36) (see also Petroleum, drilling fluids). 

API Bulletin 13A Oil Well Drilling Fluid Materials, API, Dallas, 1983. 

Other uses of thickening agents include pharmaceutical preparations, paper production, and oil well drilling fluids. This latter use is necessary because oil is obtained from rock that is porous. In order to remove the oil without altering the mechanical properties of the porous rock, viscous liquids ( drilling fluids ) are pumped into the rock to replace the oil. Among the substances that can be used for this purpose are thickened aqueous solutions of polymers such as poly(acrylic acid) or poly(acrylonitrile). 

Viscometer test. Typical crosslinked starches are obtained when the initial rise of the viscosity of the product is between 104° and 144° C, and the viscosity of the product does not rise above 200 Brabender units at temperatures less dian 130° C. The crosslinked starch slurry is then drum-dried and milled to obtain a dry product. The effectiveness of the product is checked by the API Fluid Loss Test after static aging of sample drilling fluids containing the starch at elevated temperatures. The milled dry product can then be incorporated into the oil well drilling fluid of the drill site. 

Polyether Compounds for Oil-Based Well Drilling Fluids... 

A liquid oil, an emulsifier, and a friction modifier, which includes certain polyether compounds, can be added to a drilling fluid consisting of a water-in-oil emulsion formed from a brine [1155]. The friction modifier serves to decrease the coefficient of friction of the well drilling fluid. Decreasing the coefficient of friction lowers the force required to turn the drill bit in the hole. Gravitational forces increase the coefficient of friction in deviated-, horizontal-, and extended-reach wells. 

A mixture of sulfonated styrene-maleic anhydride copolymer and polymers prepared from acrylic acid or acrylamide and their derivatives [759] are dispersants for drilling fluids. The rheologic characteristics of aqueous well drilling fluids are enhanced by incorporating into the fluids small amounts of sulfonated styrene-itaconic acid copolymers [761] and an acrylic acid or acrylamide polymer [755]. 

C. J. Bemu. High temperature stable modified starch polymers and well drilling fluids employing same. Patent EP 852235,1998. 

D. Dino and J. Thompson. Organophilic clay additives and oil well drilling fluids with less temperature dependent rheological properties containing said additives. Patent EP 1138740A, 2001. 

A. H. Hale. Well drilling fluids and process for drilling wells. Patent US 4728445, 1988. 

G. A. Malchow, Jr. Friction modifier for oil-based (invert) well drilling fluids and methods of using the same. Patent US 5593953, 1997. 

K. McNally, H. Nae, and J. Gambino. Oil well drilling fluids with improved anti-settling properties and methods of preparing them. Patent EP 906946, 1999. 

R. Williamson. Well drilling fluids, fluid loss additives therefor and preparation of such additives. Patent GB 2178785, 1987. 

Gray, G.R., Darley, H.C.H., Rogers, W.F. "Compositions and Properties of Oil Well Drilling Fluids" 4th Ed, Gulf Publishing Houston, TX 1980. 

Well drilling fluids having clay control properties were prepared by Hurd et al. 

Alkylphenol ethoxylates are chemically stable and highly versatile surfactants that find application in a large variety of industrial products including acid and alkaline metal cleaning formulations, hospital cleaners, herbicides (qv) and insecticides, oil-well drilling fluids, synthetic latices, and many others (see Disinfectants and antiseptics Elastomers, synthetic Insect control technology Metal surface treatments Pesticides Petroleum, drilling fluids). 

Measuring particle-size distribution and colloid content of oil-well drilling fluids. Um. S. Bur. Mines Rept. Investigations 3549. 

Surfactants based on aliphatic alcohols are used as cleaners in both domestic and industrial applications. They provide excellent properties such as wetting, dispersion, and emulsification. The ethoxylates derived from alkylphenols are chemically stable and highly versatile, finding more use in industrial practice than in domestic applications. They are used both as processing aids and as components in various products. Their applications include metal cleaning, hospital cleaners and disinfectants, agricultural chemical formulation surfactants, insecticides and herbicides, oil-well drilling fluids, and many others. 

As shovvm in Table I, petroleum emulsions may be desirable or undesirable. For example, one kind of oil-well drilling fluid (or mud O is emulsion based. Here a stable emulsion (usually oil dispersed in water) is used to lubricate the cutting bit and to carry cuttings up to the surface. This emulsion is obviously desirable, and great care goes into its proper preparation. 

Use Ceramic products, refractories, colloidal suspensions, oil-well drilling fluids, filler for rubber and plastic products, films, paper coating, decolorizing oils, temporary molds, filtration, carrier in insecticidal sprays, catalyst support. 

Use Vegetable tanning, retanning of chrome-tanned upper leathers, dyeing, ore flotation, oil-well drilling fluids, flavoring. 

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