Fluid losses

Polyacrylamides are used in many other oilfield appUcations. These include cement additives for fluid loss control in well cementing operations (127), viscosity control additives for drilling muds (128), and fracturing fluids (129). Copolymers [40623-73-2] of acrylamide and acrylamidomethylpropanesulfonic acid do not degrade with the high concentrations of acids used in acid fracturing. 

Weight loss is a good iadicator of fluid loss and excretion. The first wave of fluid mobili2ed is from the periphery. The excretion of chloride and... 

Lead dioxide candle A device for determining the amount of sulfur dioxide in the air. The SO, reacts with a film of lead dioxide to produce lead sulfate, which is measured to determine the concentration. Leakage The rate of fluid loss from an enclosure due to a pressure difference between the inside and outside of the enclosure. 

Filtration. The API filtration test for oil-base muds usually gives an all-oil filtrate. The test may not indicate downhole filtration, especially in viscous oils. The alternative high-temperature-high-pressure (HT-HP) filtration test will generally indicate a pending mud problem by amount of fluid loss or water in the filtrate. 

Dispersed Noninhibited Systems. Drilling fluid systems typically used to drill the upper hole sections are described as dispersed noninhibited systems. They would typically be formulated with freshwater and can often derive many of their properties from dispersed drilled solids or bentonite. They would not normally be weighted to above 12 Ib/gal and the temperature limitation would be in the range of 176-194°F. The flow properties are controlled by a deflocculant, or thinner, and the fluid loss is controlled by the addition of bentonite and low viscosity CMC derivatives. 

Dispersed Inhibited Systems. Dispersed inhibitive fluids attempt to combine the use of dispersed clays and deflocculants to derive the fundamental properties of viscosity and fluid loss with other features that will limit or inhibit the hydration of the formation and cuttings. It will be realized these functions are in opposition therefore the ability of these systems to provide a high level of shale inhibition is limited. However, they have achieved a high level of success and in... 

In oil-producing formations with high fluid loss, drilling in with foam and foam completion proves beneficial. Usually, these formations cannot stand a column of water—so it is impossible to establish returns with conventional mud. The use of foam for drilling in and completion results in substantial increases in production. 

Control mud weight to counter balance pore pressure. Keep fluid loss as low as possible. Keep viscosity and gel strength low to prevent swabbing. 

The design factors to prevent blocking involve the use of low-viscosity fluids with minimum interfacial tension, minimum capillary pressure, and minimal fluid loss. 

Fluid loss Ideal requirements no fluid loss. Practical recommendations Fluid loss to the formation can be controlled by (1) fluid-loss agents or vixcositiers such as polymens, calcium carbonate, gilsonit, asphalt etc., (2) bridging materials. 

Brine-polymer systems are composed of water-salt solutions with polymers added as viscosifers or filtration control agents. If fluid loss control is desired, bridging material must be added to build a stable, low permeability bridge that will prevent colloidal partial movement into the formation. 

Starch is also used for fluid loss control. It does not provide carrying capacity therefore other polymers are required. Although starch is relatively cheap, it has two serious limitations (1) starch is subject to fermentation, and (2) it causes significant permeability reduction due to plugging. 

Drilling fluid type and properties (density, viscosity, fluid loss, etc., solids content, differential pressure, etc.)... 

An injectivity test is performed using clean, solids-free water or brine. If a low fluid loss completion fluid is in the hole, it must be displaced from the perforations before starting the injecting. This test will give an idea of the permeability of the formation to the cement filtrate. 

Occurs when the volume of extracellular fluid is significantly diminished. Examples include hemorrhage, fluid loss caused by burns, diarrhea, vomiting, or excess diuresis Occurs when the heart is unable to deliver an adequate cardiac output to maintain perfusion to the vital organs. Examples include as the result of an acute myocardial infarction, ventricular arrhythmias, congestive heart failure (CHF), or severe cardiomyopathy. 

TH E PATIEN T WITH ED EM A. Fhtients with edema caused by heart failure or other causes are weighed daily or as ordered by the primary health care provider. A daily weight is taken to monitor fluid loss. Weight loss of about 2 lb/d is desirable to prevent dehydration and electrolyte imbalances. The nurse carefully measures and records the fluid intake and output every 8 hours. The critically ill patient or the patient with renal disease may require more frequent measurements of urinary output. The nurse obtains the blood pressure, pulse, and respiratory rate every 4 hours or as ordered by the primary health care provider. An acutely ill patient may require more frequent monitoring of the vital signs. 

Q Deficient Fluid Volume related to inability to take oral tluids, abnormal fluid loss, other lactors (specify cause ot deficient fluid volume)... 

The flow properties are controlled by a flocculant or thinner, and the fluid loss is controlled with bentonite and carboxymethylcellulose. 

Lignite muds are high-temperature resistant up to 230° C. Lignite can control viscosity, gel strength, and fluid loss. The total hardness must be lower than 20 ppm. 

Commercial products are listed in the literature. These include bactericides, corrosion inhibitors, defoamers, emulsifiers, fluid loss and viscosity control agents, and shale control additives [58-61,65]. 

Polyethercyclicpolyols possess enhanced molecular properties and characteristics and permit the preparation of enhanced drilling fluids that inhibit the formation of gas hydrates prevent shale dispersion and reduce the swelling of the formation to enhance wellbore stability, reduce fluid loss, and reduce filter-cake thickness. Drilling muds incorporating the polyethercyclicpolyols are substitutes for oil-based muds in many applications [195-197,1906,1907]. Polyethercyclicpolyols are prepared by thermally condensing a polyol, for example, glycerol to oligomers and cyclic ethers. 

Anionic Association Polymer. Another type of lost circulation agent is a combination of an organic phosphate ester and an aluminum compound, for example, aluminum isopropoxide. The action of this system as a fluid loss agent seems to be that the alkyl phosphate ester becomes crosslinked by the aluminum compound to form an anionic association polymer, which serves as the gelling agent [1488]. 

Alkylpolyglucosides (APGs) are highly biodegradable surfactants [1344]. The addition of APGs, even at very low concentrations, to a polymer mud can drastically reduce the fluid loss even at high temperatures. Moreover, both fluid rheology and temperature resistance are improved. 

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