Hydraulic Hydrocarbon

FIG. 10-25 NPSH reductions for pumps handling hydrocarbon liquids and high-temperature water. This chart has been constructed from test data obtained using the liquids shown Hydraulic Institute Standards). 

Both the dipolymers and terpolymers have excellent resistance to hydrocarbons found m petroleum-based fuels and lubricants The 69 5% F terpolymer resists swellmg m blended fuels that contain metlianol and can be used in contact with certain phosphate ester-based hydraulic fluids Terpolymers are preferred for contact with aromatic solvents, although either type performs well in higher alcohols VDF-based elastomers dissolve m polar aprotic solvents such as ketones, esters, amides, and certam ethers These elastomers are therefore not suitable for contact with fluids that contain substantial amounts of these solvents because of excessive swell and consequent loss of mechanical properties... 

For hydrocarbons and water significantly above room temperatures, the Hydraulic Insdtute [17] recommends the use of a correction deduction as given in Figure 3-46. This indicates that the required NPSH as given on the pump curves can be reduced for conditions within the range of the curve based on test data. 

Al = Cross-secdonal area allocated to lighL phase, sq ft Ap = Area of particle projected on plane normal to direction of flow or motion, sq ft A, = Cross-sectional area at top of vessel occupied by continuous hydrocarbon phase, sq ft ACFS = Actual flow al conditions, cu ft/sec bi = Constant given in table c = Volume fraction solids C = Overall drag coefficient, dimensionless D = Diameter of vessel, ft Db = See Dp, min Dc = Cyclone diameter, ft Dc = Cyclone gas exit duct diameter, ft Dh = Hydraulic diameter, ft = 4 (flow area for phase in question/wetted perimeter) also, DH in decanter design represents diameter for heavy phase, ft... 

Acrylics, A copolymer of 2-ethylhexylacrylate and acrylic acid is not soluble either in water or in hydrocarbons. The ester units are hydrophobic and the acid units are hydrophilic. An aqueous suspension with a particle size smaller than 10 p can be useful in preparing aqueous hydraulic fracturing fluids [776]. 

Water Solubility of Hydrocarbon Components of Mineral Oil Hydraulic Fluids... 

Hydraulic fluids themselves cannot be measured in blood, urine, or feces, but certain chemicals in them can be measured. Aliphatic hydrocarbons, which are major components of mineral oil hydraulic fluids and polyalphaolefin hydraulic fluids, can be detected in the feces. Certain components of organophosphate ester hydraulic fluids leave the body in urine. Some of these fluids inhibit the enzyme cholinesterase. Cholinesterase activity in blood can be measured. Because many other chemicals also inhibit cholinesterase activity in blood, this test is not specific for organophosphate ester hydraulic fluids. This test is not available at most doctor s offices, but can be arranged at any hospital laboratory. See Chapters 2 and 6 for more information. 

The third class of hydraulic fluids discussed in this profile is the polyalphaolefins. Polyalphaolefins are synthetic hydrocarbons that are made by oligomerizing alphaolefins such as 1-decene (see Chapters 3,4, and 5). Aliphatic hydrocarbons are the principal components of both mineral oils and polyalphaolefins, but the array of hydrocarbons with differing molecular weights is much narrower in polyalphaolefins than in mineral oils. Certain polyalphaolefins maintain good operational characteristics at low temperatures and have been proposed for use in hydraulic systems in U.S. military aircraft (Kinkead et al. 1992b). 

No studies were located that examined the toxicokinetics of polyalphaolefins in humans or animals, but the similarities in physical and chemical properties between polyalphaolefins and hydrocarbons in mineral oil indicate that the toxicokinetics of polyalphaolefins may be similar to those of hydrocarbons in mineral oil hydraulic fluids. 

Polyalphaolefin Hydraulic Fluids. No studies were located regarding absorption in humans or animals after inhalation exposure to polyalphaolefin hydraulic fluids or their major components. Based on physicochemical similarities with mineral oils (i.e., long-chain aliphatic hydrocarbons are predominant... 

Food-grade or medicinal mineral oil, a mixture of aliphatic hydrocarbons that also may be found in mineral oil hydraulic fluids, is known to be absorbed only to a limited extent by the human gastrointestinal tract and has a laxative effect (Anonymous 1967 Brunton 1985), thus suggesting that mineral oil hydraulic fluids may behave likewise. 

Mineral Oil and Polyalphaolefin Hydraulic Fluids. No studies were located regarding metabolism in humans or animals after exposure to mineral oil hydraulic fluids or polyalphaolefin hydraulic fluids. It should be noted, however, that hydrocarbons found in mineral oils generally are not expected to undergo extensive metabolism in animals or humans (Cannon 1940 IARC 1984). It may be speculated that polyalphaolefins may undergo limited metabolism of a similar nature. 

Mineral Oil Hydraulic Fluid. Limited studies were located that suggest biomarkers of exposure to mineral oil hydraulic fluids. No data that indicate quantitative or qualitative biomarkers of exposure to mineral oil hydraulic fluid were located. Mineral oil (hydrocarbons containing 15-30 carbon atoms per molecule) is a major component that is common to all mineral oil hydraulic fluids. Following exposure to food-grade mineral oil, most of the administered radioactivity was excreted in the feces as mineral oil (Ebert et al. 1966). Although the presence of mineral oil is a biomarker of exposure to mineral oil hydraulic fluids, it is also a biomarker of exposure to other readily available products that contain mineral oils. 

Before the 1960s, products were introduced based on alkyl aryl phosphates that could contain chlorinated aromatic hydrocarbons. Such products have now entirely disappeared from commercial use, and the vast majority of the industrial organophosphate esters are based on triaryl phosphates with no halogenated components (Marino 1992). However, at older waste disposal sites, hydraulic fluid site contaminants could contain chlorinated hydrocarbons. As with the PCBs formerly included as additives in other forms... 

Polyalphaolefin Hydraulic Fluids. Polyalphaolefms are made by oligomerizing alphaolefins such as 1-decene in the presence of a catalyst (Newton 1989 Shubkin 1993 Wills 1980). The crude reaction mixture is quenched with water, hydrogenated, and distilled. The number of monomer units present in the product polyalphaolefin oil depends on a number of reaction parameters including the type of catalyst, reaction temperature, reaction time, and pressure (Shubkin 1993). The exact combination of reaction parameters used by a manufacturer is tailored to fit the end-use of the resulting polyalphaolefin oil. A typical polyalphaolefin oil prepared from 1-decene and BF3- -C4H9OH catalyst at 30 °C contains predominantly trimer (C30 hydrocarbons) with much smaller amounts of dimer, tetramer, pentamer, and hexamer. While 1-decene is the most common starting material, other alphaolefins can be used, depending on the needs of the product oil. 

Polyalphaolefin Hydraulic Fluids. None of the known components of polyalphaolefin hydraulic fluids are on the TRI. Releases of polyalphaolefin hydraulic fluids in air are probably similar to mineral oil hydraulic fluids. It may be difficult to estimate the release of polyalphaolefin hydraulic fluids to air by identifying occurrences of polyalphaolefin hydrocarbon isomers in air at a particular facility since these constituents also are present in mineral oil and concentrations of the components cannot always be uniquely associated with polyalphaolefin hydraulic fluid release. Nonetheless, the gas chromatographic profile of a polyalphaolefin will be very different than that of a mineral oil, and identification may be possible when polyalphaolefins predominate in a sample. 

Mineral Oil Hydraulic Fluids. No information identifying the major components of mineral oil or water-in-oil hydraulic fluids was located in the available literature, nor was any information located that described how the emulsifiers and other components in water-in-oil emulsion hydraulic fluids alter the environmental properties of the mineral oils contained in them. The carbon number range present in mineral oil hydraulic fluids probably is from C15 to C50 (IARC 1984 Shubkin 1993 Wills 1980). If automatic transmission fluids are typical of the mineral oil content in a hydraulic fluid, then mineral oil hydraulic fluids contain -90% mineral oil (Abdul et al. 1990 Papay 1989,1991). Therefore, the transport and partitioning of these hydrocarbons will largely account for the environmental behavior of mineral oil hydraulic fluids. Typical transport and partitioning information for hydrocarbons in this range is presented below this information is indicative of the transport and partitioning of mineral oils present in hydraulic fluids. 

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