Liquid phase saturation

Fig 18. Experimental trickle-bed system A, tube bundle for liquid flow distribution B, flow distribution packing of glass helices C, activated carbon trickle bed 1, mass flow controllers 2, gas or liquid rotameters, 3, reactor (indicating point of gas phase introduction) 4, overflow tank for the liquid phase feed 5, liquid phase hold-up tank 6, absorber pump 7, packed absorption column for saturation of the liquid phase 8, gas-liquid disengager in the liquid phase saturation circuit. (Figure from Haure et ai, 1989, with permission, 1989 American Institute of Chemical Engineers.)... 

Concentration of A Arrhenius constants Arrhenius constant Constant in equation 5.82 Surface area per unit volume Parameter in equation 5.218 Cross-sectional area Concentration of B Stoichiometric constants Parameter in equation 5.218 Concentration of gas in liquid phase Saturation concentration of gas in liquid Concentration of G-mass Concentration of D-mass Dilution rate DamkOhler number Critical dilution rate for wash-out Effective diffusion coefficient Dilution rate for maximum biomass production Dilution rate for CSTF 1 Dilution rate for CSTF 2 Activation energy Enzyme concentration Concentration of active enzyme Active enzyme concentration at time t Initial active enzyme concentration Concentration of inactive enzyme Total enzyme concentration Concentration of enzyme-substrate complex with substance A... 

H therefore has the units of Pa mol and can be estimated by ratioing a chemical s liquid-phase saturation vapour pressure (usually the sub-cooled liquid vapour pressure) over its aqueous solubility, at some reference temperature. Note that the vapour pressure (P) can be readily converted into solubility with units of molar concentration by applying the ideal gas law... 

Gladkii(16) at the State Scientific Research Institute of Industrial and Sanitary Gas Cleaning at Moscow did work on the three-phase calcium sulfite slurry oxidation system, finding that the liquid phase oxidation (pH 3.6-6) is first order with respect to the sulfite species. He pointed out, on the basis of pH versus time data from his semi-batch reaction, that the slurry oxidation had different periods in which either reaction kinetics or solid-liquid mass transfer controlled the oxidation rate. He also presented an omnibus empirical correlation between pH, temperature, and the liquid phase saturation concentration of calcium sulfite solution for predicting the slurry oxidation rate. The catalytic effect of manganese... 

In the implementation, each algebraic equation is linked to a primary variable. Thus, the algebraic equation for air is linked to gas pressure, the equation for water is linked to liquid phase saturation and the energy equation is linked to temperature. The system of equations can be solved in two ways in the TH model either they are solved iteratively, gas pressure and liquid saturation are solved simultaneously, followed by temperature, as shown in the system of equations (7). 

Figure 7. Results of desaturation example, (a) liquid phase saturation, (b) gas phase pressure, (c) vapour mass fraction, (d) Temperature.

Figure 8. Preliminary BMTl Results (a) Temperature evolution, (b) Liquid phase saturation evolution in the observation points.

Fig. 1.10. Cooling curves (a) and a portion of the diagram of state (b) of HDPE-vacuum oil system L, a and j3 - zones of liquid phase existence (melt), solid solutions of PE in oil and oil in PE, respectively L +/3, a - - / - zones of coexisting liquid phase, solid solution and two solid solutions Li- - L2 - stratification zone of two liquid phases (saturated polymer solution in oil and vice versa) ELC and ENC - liquids and solids lines...

After equilibrium is reached the tank is set offstream and the liquid phase (saturated with gas) is recirculated through the loop only. The loop temperature is then decreased at a constant rate of lO C/h from 20 C down to 4°C. This temperature is then kept constant during the whole test period, i.e., about 20 h if pipe plugging has not occurred. At the end of each test the loop is heated to 25 C and maintained at this temperature for several hours in order to ensure complete hydrate dissociation. The loop is then ready for the next test after a new stabilization period at 20 C. 

SSR 1,0 at 100 seconds is about 100 times faster than the rate of O2 absorption over the range of oxygen concentrations tested. Therefore, the liquid phase saturation concentration would tend to be less than one would expect from steady-state conditions. However, acting to oppose this is the escape of water molecules from the surface solution, which would tend to concentrate the oxygen in the liquid at the interface. The net effect as shown in Figure 8 for SSR =1.0, 1.5 is to produce an equilibrium concentration somewhat lower than the steady-state case for t... 

At low volume expansion, particles are being formed by precipitation from a liquid phase at the bottom of the precipitator. The liquid phase saturated with anti-solvent is formed as the result of vapor-liquid equilibrium at operating pressure and temperature. Under these conditions the... 

As the liquid-phase saturation increases, the isosate G moves fi om the left to the right. Under the absence of eapiUary forces, the isosate Gi corresponding to the unity saturation eoineides with the seetion CNCj of the main binodal. If the largest radius of a pore in the... 

Important to any measurement of citrus juice volatile flavor components is the presence of (i-limonene, since this compound is naturally present as the most concentrated component in all of the natural citrus oils. Also, the solubility of d-limonene in aqueous media must be considered, since after liquid phase saturation, the headspace concentration remains constant. It has long been established for d-limonene and similar nonpolar flavor compounds over water that meaningful headspace measurement techniques [e.g., solid-phase microextraction (SPME)] require equilibrium of the vapor and liquid phase concentrations. Equilibrium may take a number of hours for static (unstirred) experiments and less than 1 hr for stirred systems. These conditions have been discussed elsewhere, and solubility and activity coefficients of d-limonene in water and sucrose solutions have been determined [1,2]. More recently, the chemical and physical properties as well as citrus industry applications of d-limonene and other citrus essential oils have been compiled [3]. Although not specific to d-limonene, important relationships affecting behavior of flavor release and partitioning between the headspace and the liquid phase of a number of food systems have also been discussed [4]. 

Method developments for food headspace SPME analyses have considered some, but not all, important issues related to equilibria and capacities of the various fibers. Dilutions for gas chromatography olfactometry (GCO) were monitored as a result of compound mass distribution between the headspace and liquid however, there was no indication of how to deal with liquid phase saturation [7]. The requirement for calibration of fibers by use of standard solutions has also been addressed, considering the various parameters needed to calculate supposed headspace concentrations for dilution analysis [8]. Comparing static headspace vapor sampling with SPME for citrus volatile compounds in standard solutions below the solubility limits [parts per billion (ppb)] of most of the compounds resulted in linear calibration curves however, curves were nonlinear at [parts per million (ppm)] concentrations above solubility limits [9]. This study [9] determined that there were analytical differences between actual juices, but these differences were nonquantitative. 

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