Percent saturation

Percent saturation is the ratio of the partial pressure of a condensable vapor ia a gas to the vapor pressure of the Hquid at the same temperature, expressed as a percentage. For water vapor ia air this is called percent relative humidity. 

Vapors (from drying) are removed at the feed end of the dtyer to the atmosphere through a natural-draft stack and settling chamber or wet scrubber. When employed in simple drying operations with 3.5 X 10 to 10 X 10 Pa steam, draft is controlled by a damper to admit only sufficient outside air to sweep moisture from the cylinder, discharging the air at 340 to 365 K and 80 to 90 percent saturation. In this way, shell gas velocities and dusting are minimized. When used for solvent recovery or other processes requiring a sealed system, sweep gas is recirculated throu a scrubber-gas cooler and blower. 

Example 6 Solvent Rate for Absorption Let us consider the absorption of acetone from air at atmospheric pressure into a stream of pure water fed to the top of a packed absorber at 25 C. The inlet gas at 35 C contains 2 percent by volume of acetone and is 70 percent saturated with water vapor (4 percent H2O by volume). The mole-fraction acetone in the exit gas is to be reduced to 1/400 of the inlet value, or 50 ppmv. For 100 kmol of feed-gas mixture, how many Idlomoles of fresh water should be fed to provide a positive-driving force throughout the pacldug How many transfer units will be needed according to the classical adiabatic method What is the estimated height of pacldug required if Hqq = 0.70 m ... 

Model is relatively insensitive to changes in k over a three-fold range of 0.02-0.06 day Predicted DO concentrations deviate no more than 6 percent saturation from standard profile. 

Model is sensitive to variations in ammonia-N loading. A doubling of loads (from outfalls in the nitrifying segment) results in as much as a 14 percent reduction in percent DO saturation values from the standard profile. Reducing the ammonia loading by 50 percent increases the predicted DO values by up to 8 percent saturation. 

Model is insensitive to expected range of changes in summertime water depth in the tidal reach. Predicted DO values differ from standard profile by an average of 1 percent saturation. 

PTCA Percutaneous transluminal coronary angioplasty Sao2 Arterial oxygen percent saturation... 

FIGURE 3.29 Soil zones defined by percent saturation. (Modified after Abdul, 1988.)... 

Depth profiles of (a) salinity (%o), (b) dissolved oxygen (ml /L), and (c) percent saturation of dissolved oxygen in the Southeastern Atlantic Ocean (9°30 W 11°20 S). Samples were collected in March 1994. Dotted lines represent the curves generated by the one-dimensional advection-diffusion model (see text for details). The values of Dz, Vz, and J are the ones that best fit the data. Data are from Java Ocean Atlas (http /odf.ucsd.edu/joa). Values of percent saturation of oxygen less than 100 reflect the effects of aerobic respiration. Values greater than 100 indicate a net input, such as from photosynthesis. (See companion website for color version.)... 

Annual percent saturation of dissolved oxygen in (a) surface waters (Om) and (b) 50 m water depth. Source-. From Garcia, FI. E., et al. (2006). World Ocean Atlas 2005, Volume 3 Dissolved Oxygen, Apparent Oxygen Utilization, and Oxygen Saturation. NOAA Atlas NESDIS 63, U.S. Government Printing Office, p. 342. 

Changes in percent saturation caused by the mixing of two water masses, (a) Mixing scenario and (b) noniinear temperature effect. 

The effects of photosynthesis are clearly seen in the low TDIC and nutrient concentrations of the surface water. The O2 concentrations are high because of contact with the sea surfece and production by phytoplankton. The temperature and O2 concentration data have been used to compute the percent saturation with respect to O2. The high degree of supersaturation in the surfece water suggests that the rate of O2 supply via photosynthesis is exceeding its removal via the dual processes of aerobic respiration and degassing across the air-sea interface. 

Horizontal distributions of (a) 02(mLyL), (b) percent saturation of 02(%), (c) phosphate ( j,mol/L), (d) nitrate ( ji,mol/L), and (e) silicate ( ji,mol/L) at 4000 m depth in the worid s major ocean basins. The horizontal distribution of AOU was presented In Figure 8.2. Source After Conkright, M. E., et al. (2002). World Ocean Atlas 2001, Volume 4 Nutrients, NOAA Atlas NESDIS 52, U.S. Government Printing Office (See companion website for color version.)... 

This assvunes that the newly formed deep waters were at 100% saturation with respect to O2 when they were last at the sea surface. As noted in Chapter 6, the percent saturation of surfece water is geographically and temporally variable with an average value of 103%.) ... 

Depth Profiles where 1 dbar is approximately equal to 1 m water depth (a) Percent Saturation of O2, (b) Particulate Carbon, (c) DOC,... 

For economic reasons, equilibrium conditions cannot be approached closely. In a cooling tower, for instance, the effluent air is not quite saturated, and the water temperature is not quite at the wet bulb temperature. Percent saturation in the vicinity of 90% often is feasible. Approach is the difference between the temperatures of the water and the wet bulb. It is a significant determinant of cooling tower sizfe as these selected data indicate ... 

Sublimation pressures down to 0.001 bar are considered feasible. At lower pressures and in some instances at higher ones, entrainer gas is used, usually air or nitrogen or steam. By such means, for instance, salicyclic add is purified by sublimation at 150°C with an entrainer of air with sufficient C02 to prevent decarboxylation of the acid. At the operating temperature, the vapor pressure is only 0.0144 bar. Operating conditions corresponding to equilibrium in the sublimer appear in Figure 19.11. Equilibrium may be approached in equipment where contact between phases is intimate, as in fluidized beds, but in tray types percent saturation may be as low as 10%. 

Figure 19.11. Sublimation of salicyclic acid at 1 bar. Vapor pressures are 14.4 mbar at 150°C and 0.023 mbar at 40°C. The air rate shown corresponds to equilibrium in the sublimer, but in some kinds of vessels percent saturation may be as low as 10%. The conditions are those of Mullin [Crystallisation, Butterworths, London, 288 (1972)].

The percent saturation is never greater than the relative saturation except at saturated conditions or at zero percent saturation (where % saturation = % RH). 

For an electron number density of 1015 m 3 and a mobility of 0.022 (m2/V-s), calculate the time required to reach 99 percent of the saturation charge of an initially neutral particle by field charging. If the length of the charging chamber is 5 cm, what is the maximum particle velocity allowed to ensure 99 percent saturation charge ... 

Thirty crude oils from the BCF were collected (1) along two parallel and generally southwest-northeast trends. The areal extent of the BCF showing locations of wells sampled is shown in Figure 1. These oils were characterized by their API gravity, percent saturates, aromatics, NSO and asphaltene compounds, gas chromatograms for whole oils, CA-C7 fractions, and aromatics. Concurrently, 24 associated waters were also sampled and analyzed for Ca++, Mg++, Na+, HC03, C03 , SOA , pH, and total dissolved solids (TDS) (1). 

It is generally recommended that not more than 30 percent of one s dietary calories should derive from fat (and of this 30 percent, 10 percent should be monounsaturated, and 10 percent, polyunsaturated). It appears that consumption of greater amounts of saturated fats (compared to amounts of monounsaturated and polyunsaturated fats) is related to higher levels of cholesterol in the blood and a greater risk of heart disease. In the United States the average diet is about 34 percent fat and (13 percent saturated fat). 

The low concentration of Orange OT in the micelles, and especially in the water, keeps the competition between these two solvents unaffected by the dissolved dye. Hence, the distribution ratio between micelles and water is constant from zero to saturation, and at equilibrium the percent saturation is the same for both and for the whole system. This equilibrium is also presumably established extremely rapidly and is therefore maintained at each point during the relatively slow changes involved in the usual transport processes. 

The difference in the behavior of hemoglobins may be shown graphically in another way by plotting percent saturation with oxygen against p02, as is shown in Figure 7.6b. Mathematically, this plot may be represented by the equation... 

A patient s serum sample has a TI of 55 mg/dL and a TIBC of 657 mg/dL. What is the transferrin content (mg/dL) of the sample and what is its percent saturation with iron Molecular weight of transferrin is 80,000 atomic weight of iron is 56. 

The oxygen affinity is reduced (p50 is 70 torr, and the arterial blood is only 70 percent saturated). 

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