Salinity effective

Denture stomatitis. Coconut soap, associated with 05% sodium hypochlorite, used by patients for 15 days, significantly reduced clinical signs of denture stomatitis and was effective in controlling denture biofilm . Desensitization effect. Saline extract of the dried pollen, administered subcutaneously to 96 allergic adults at variable doses, produced a clinical improvement and decreased IgE levels ". 

Other Secondary Effects Salinity, pH, Gametogenesis, and Changes in Seawater Mg/Ca... 

To combine the effects of monovalents and divalents, UTCHEM uses the concept of effective salinity, which is defined as... 

To consider the effect of divalent cations bound to micelles, the effective salinity is (Hirasaki, 1982a)... 

To consider the effect of alcohol on the effective salinity, we extend the Hirasaki (1982a) model. The effective salinity is... 

The simple way to avoid any mistakes when fitting the laboratory data to Eq. 5.1 is to use the same units as those in the prediction model (e.g., a simulator) you are going to use. Then those fitting constants obtained by matching experimental data can be directly used in the prediction model. The factor allows for dependence of polymer viscosity on salinity and hardness. The effective salinity for polymer, C ep, is given in UTCHEM-9.0 (2000) by... 

Most often, the total amount of chloride is used because NaCl is the most common salt. The justification of using it is that the current technology really cannot describe the effect of every single ion on chemical EOR. For example, when HPAM reacts with multivalent metal ions, such as Cr ", and Ti ", in a solution, a weak gel is formed. In this case, we cannot simply use Eq. 5.2 to calculate effective salinity. Equation 5.2 shows that divalents have a larger effect on the effective salinity than monovalents at the same concentration. In general, the order of effect is Mg " > Csl > Na" > The activity of these ions is 10 to 20 kJ/mol, which is much less than the value for chemical reactions (about 200 kJ/mol). Therefore, the salt effect on polymer solution is a reversible electrostatic effect (Niu et al 2006). 

This section describes how to use Hand s rule to represent binodal curves and tie lines. The surfactant-oil-water phase behavior can be represented as a function of effective salinity after the binodal curves and tie lines are described. Binodal curves and tie lines can be described by Hand s rule (Hand, 1939), which is based on the empirical observation that equilibrium phase concentration ratios are straight lines on a log-log scale. Figures 7.15a and 7.15b show the ternary diagram for a type II(-) environment with equilibrium phases numbered 2 and 3 and the corresponding Hand plot, respectively. The line segments AP and PB represent the binodal curve portions for phase 2 and phase 3, respectively, and the curve CP represents the tie line (distribntion cnrve) of the indicated components between the two phases. Cy is the concentration (volnme fraction) of component i in phase) (i or j = 1, 2, or 3), and 1, 2, and 3 represent water, oil, and microemulsion, respectively. As the salinity is increased, the type of microemulsion is changed from type II(-) to type III to type II(-i-). C, represents the total amount of composition i. 

Theoretically, Eq. 7.12 applies at any point, including the plait point in the binodal cnrve, which covers phases 2 and 3 for the type II(-) environment. Therefore, the valne of Ah for phase 1 is the same as that for phase 3. Similarly, the valne of Ah for phase 1 is the same as that for phase 3 for the type II(+) environment. However, we assume that the surfactant is in phase 3 (the micro-emnlsion phase). When we use Eq. 7.12 to calculate Ah, j = 3, in general, we nse experimental data to calculate Ah at different effective salinities (C e), as shown in Eignre 7.16 (dot points), assuming that the surfactant is in phase 3 (microemnlsion phase). 

For the II(-i-) left lobe, the plait point is calculated by interpolation on effective salinity ... 

As we can see in Figure 7.11 and Table 7.3, the invariant point moves from C2M equal to 0 to C2M equal to 1 as the salinity is increased from Csei to Cseu-Csei to Cseu the lower and upper effective salinity limits for type 111 microemulsion. Based on this general observation, it has been proposed that C2M is interpolated linearly as a function of salinity from Csei to Cse (L.W. Lake, personal communication on June 25, 2009) ... 

In this way, we can maintain exactly the same salinity as in the pipette test (optimum salinity now), although the initial salinity could be arbitrary because it will be displaced by a large volume of injected solution, and eventually it will be replaced by the injected salinity. The injected salinity must be the same as that in the pipette test. We should always check the resulting effective salinity (in the. SALT file) to confirm that the effective salinity has not been changed after the simulation is completed. The other phase behavior parameters can be left the same as the default numbers in the batch.txt because they may not affect the results at the optimum salinity. Note that the input salinity in the injection solution, C(M,KC,L), is the salinity in the injected aqueous phase, C5, which is not effective salinity. However, in. SALT, the output is the effective salinity, which is defined as... 

The input parameters—C50 (initial brine salinity), C60 (initial brine divalents), CSEL7 and CSEU7 (Cjei and when alcohol and divalents are 0) in UTCHEM input—are effective salinities in meq/mL water. 

If we input Cjjmaxi = 0.03, Cjs axo = C33max2 = 0.06, and injected salinity C(M,KC,L) = Cii X Cse = 0.99 x 0.36S = 0.3614 meq/mL solution (not water), the effective salinity in. SALT is then exactly equal to 0.355 meq/mL water. Here, C, = 1 - C31 = 1 - 0.01 = 0.99 because the surfactant concentration is 1%. In C(M,KC,L), M denotes the well number, which is 1 for the injector in this simulation model KC denotes the component number, which is 5 for anion and L denotes the phase number, which is 1 for the injected aqueous phase. The solubilization ratios C23/C33 and C13/C33 from the simulation are the same—1 5.2. This solubilization ratio is lower than the experimental data—15.8. To improve this ratio, we reduce C33maxi to 0.03 X 15.2/1 5.8 = 0.0289 and keep the other parameters unchanged. Then we have the solubilization ratios equal to 1 5.8. Thus, we have matched the point at the optimum salinity. 

Hirasaki et al. (2008) demonstrated an alternative to the use of alcohol by blending two dissimilar surfactants a branched alkoxylated sulfate and a double-tailed, internal olefin sulfonate. The presence of cosolvent affects the effective salinity and causes a shift in phase boundaries. Alcohol is an organic compound with a functional group of -OH. In aqueous solutions, the hydrogen can become detached, producing slightly acidic solutions. Alcohols with short... 

The effective salinity in anion concentration in the presence of alcohol and divalents is defined as ... 

Be aware that the effect of alcohol and divalents on the optimum salinity and the effect on the effective salinity are opposite, as shown by Eqs. 7.63 and 7.65. When a divalent exists in the system, the optimum salinity in terms of monovalent concentration (C51) of the system should be lower than that had the system not had the divalent. However, when a divalent does exist in the system, because of the divalent contribution to the salinity effect, the effective salinity will become higher than the salinity of C51. The alcohol effect (contribution) is opposite to the divalent effect. 

Effect of Salinity on Adsorption and Recovery Factor UTCHEM uses the Langmuir-type isotherm equation to describe surfactant adsorption. The adsorption is directly proportional to the coefficient 83 in the equation, which is defined as 83 = 831 + 832 x C e, where Cse is the effective salinity. We can see that by changing 832, we can change the level of salinity sensitivity. Higher salinity leads to higher surfactant adsorption. 

FIGURE 10.28 Effective salinity and effective salinity limits for Type III at 0.9 PV injection. 

Based on Eq. 12.1, optimum salinity follows the logarithmic mixing rule. Mohammadi et al. (2008) replaced the ratio of oil to surfactant concentration shown in Figure 12.5 by soap molar fraction and used the more generally effective salinity in the vertical axis. They did so because they could get these values from UTCHEM simulation models. Based on the logarithmic mixing rule, both axes in such activity maps are in logarithmic scales, and the upper and lower boundaries should be linear. 

When an alkali is injected into a reservoir with acidic crnde oil, a fraction of acid components are converted into soap, which helps to solnbilize oil and water into the microemnlsion phase. Figure 12.18 shows the water and oil soln-bilization ratios at different effective salinities, based on the two dehnitions. One dehnition is the ratio of water or oil volume (V or Vo) to the volume of injected synthetic surfactant in the microemulsion phase. The other dehnition is the ratio of water or oil volume (V or Vo) to the total volume of injected... 

Pp effective salinity parameter for divalents (calcium) to calculate... 

Cj = saturation in O2 under effective salinity, temperature and pressure conditions. 

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