Concentration of dissolved solids

Dissolved Solids None Dissolved solids is measure of total amount of dissolved matter, determined by evaporation high concentrations of dissolved solids are objectionable because of process interference and as a cause of foaming in boilers Various softening processes, such as lime softening and cation exchange by hydrogen zeolite, will reduce dissolved, solids demineralization distillation reverse osmosis electrodialysis... 

Where water is evaporated from a circuit, such as a cooling tower, evaporative condenser, or humidifier, it must be remembered that there is no way of avoiding a steady bleed-off or frequent flushing, to restrict the concentration of dissolved solids. Much trouble arises from the efforts of well-wishing but misguided persons who stop the flow of bleed-off to save water . 

By contrast, the fluid concentrations of conservative components are determined by their supply to the fluid. Once in solution they remain there. Waters that have percolated through sediments containing evaporites contain the highest concentrations of dissolved solids, as, for example, the Salton Sea brines in southern California (White et al. 1963), whereas waters in basalt tend to be lowest (see Table 3). 

The injected fluids usually have a chemical composition that is different from that of the in situ reservoir fluids, particularly when steam has been separated from the liquid phase and only the separated water is re-injected. The steam phase will be enriched in non-condensable gases, whereas the separated water has a higher concentration of dissolved solids, but a lower gas content. Changes in the chemistry of the produced fluids are to be expected in all fields where re-injection of separated water has been applied. When the same water is recycled, successive steam loss will increase its salinity, which may in turn lead to scaling problems (see Amorsson, 2004). 

Among formulation variables, the moisture content particularly on surface of the material needs to be optimized. While excess surface moisture could lead to uncontrolled agglomeration, a dry extrudate can break up into fine powder. Upon spheronization for prolonged periods at high speeds, moisture gradients develop within pellets by migration from core to the surface. This is also a function of the concentration of dissolved solids and spheronizing time. The surface moisture could be lost over time, due to... 

Table 16-1 gives definitions of the several different ways of expressing the concentration of dissolved solids in formation water. 

Summary of nomenclature and units for concentration of dissolved solids in formation waters (adapted from Monograph Series, SPE 9, 38)... 

Since the current is conducted by the ions present in the water, resistivity must be related inversely to the concentration of dissolved solids. Figure 16-22 gives the relationships between resistivity, dissolved solids, and temperature.13 This graph was developed from data for sodium chloride solutions however, it is used for oilfield brines. 

Figure 16-22 has several uses. If the concentration of dissolved solids is known, the resistivity of the water at any temperature can be determined. If the resistivity of a brine at surface temperature is measured, it can be converted to reservoir temperature. Finally, if the resistivity is measured, the brine concentration can be estimated. 

Fig, 6.45. Continuous valve-body type refractometer suitable for measuring concentration of dissolved solids... 

When ice cream starts to freeze, ice nucleation begins and water will freeze out of the solution in the form of pure crystals. As water is removed from the mix in the form of ice, the concentration of dissolved solids in solution increases. The unfrozen portion of the mix becomes increasingly concentrated as freezing continues, and contains dissolved sugars, milk... 

Both a full preoperational cleaning process and a short-cycle passivation process should be carried out with minimal load on the system to limit evaporation across the tower and the concentration of dissolved solids in the system water. However, some load may be necessary to raise the temperature of the circulating water. 

This method can measure the concentration of NH3-N in water in the range 0.03 to 1400 mg/L. Color and turbidity do not affect the measurement. Distillation of sample, therefore, is not necessary. High concentration of dissolved solids in the sample, however, can cause error. Also, certain complex forming ions, such as mercury or silver, which form complex with ammonia, interfere with the test. Presence of amines in the sample can give high value. 

Distilled laboratory water has a conductivity range of 0.5-3 pmho/cm. The conductivity of drinking water in the USA ranges from 50 to 1500 pmho/cm (APHA, 1998). Conductivity of groundwater varies depending on the concentration of dissolved solids. That is why total dissolved solids (TDS) content can be estimated from a conductivity measurement. We can approximate the TDS in milligram per liter (mg/1) by dividing the conductivity value in pS/cm by a factor of two. 

It is necessary to estimate the quantity of each gas in the liquid to accurately determine the productivities and usage rates. The species equilibrium concentration, x, in the liquid is estimated by Henry s Law (Eq. 3). Unfortunately, H, the Henry s Law constant, for a gas in contact with a solution depends on the nature and concentrations of dissolved solids, tending to be less than the value for pure water [71]. For this reason, we can only obtain an upper limit for the dissolved gas quantity. However, the solubility depression for our rather dilute culture medium is low. A 0.5 mole/1 concentration of sodium chloride results in an oxygen solubility depression of 15 % [71]. The total concentration of dissolved solids in our medium was less than half of that (0.22 mole/1), so the gas solubility depression was almost certainly less than 10%. A more serious uncertainty occurs because the culture volume includes cell volume by treating the entire 83 ml as liquid volume (V ), we may tend to overestimate the dissolved gas quantity. 

The three methods for lead in air are essentially identical however, one should use S-341 because this method has been validated unlike P CAM 155 or P CAM 173. Although all the methods recommend 2-3 ml of nitric acid for wet ashing, the final solutions differ in that P CAM 155 recommends 1% nitric, P CAM 173 recommends 1% HC1, and S-341 recommends 10% nitric with EDTA 0.1 M to suppress phosphate, carbonate, iodide, fluoride, and acetate ion that cause flame suppression. EDTA is suggested in P CAM 173 where interferences are anticipated. Both S-341 and P CAM 173 use the 217.0 nm line which is twice as sensitive as the 283.3 nm line. Strong nonatomic absorption found when high concentrations of dissolved solid are present requires use of the background corrector. These two methods differ from P CAM 155 and those for biological analysis,... 

In a batch slurry reactor, the liquid-solid mass-transfer coefficient can be measured by dissolving a sparingly soluble solid in liquid. The concentration of dissolved solid in liquid (Bt) can be measured as a function of time, preferably by a continuous analytical device. Systems such as the dissolution of benzoic acid, jS-naphthol, naphthalene, or KMn04 in water can be used. A plot of B( as a function of time and the slope of such plot at time t = 0 can give ks as... 

Osmosis is a natural process where water flows through a semipermeable membrane from a solution with a low concentration of dissolved solids to a solution with a high concentration of dissolved solids. 

Picture a cell divided into 2 compartments by a semipermeable membrane, as shown in Figure 2.1. This membrane allows water and some ions to pass through it, but is impermeable to most dissolved solids. One compartment in the cell has a solution with a high concentration of dissolved solids while the other compartment has a solution with a low concentration of dissolved solids. Osmosis is the natural process where water will flow from the compartment with the low concentration of dissolved solids to the compartment with the high concentration of dissolved solids. Water will continue to flow through the membrane until the concentration is equalized on both sides of the membrane. 

At equilibrium, the concentration of dissolved solids is the same in both compartments (Figure 2.2) there is no more net flow from one compartment to the other. However, the compartment that once contained the higher concentration solution now has a higher water level than the other compartment. 

Osmotic pressure (typically represented by jt (pi)) is a function of the concentration of dissolved solids. It ranges from 0.6 to 1.1 psi for every 100 ppm total dissolved solids (TDS). For example, brackish water at 1,500 ppm TDS would have an osmotic pressure of about 15 psi. Seawater, at 35,000 ppm TDS, would have an osmotic pressure of about 350 psi. 

Recovery of the second pass can be as high as 90% with only 2 stages. This high recovery can be achieved because of the relatively low-concentration of dissolved solids in the influent to the second pass. Overall system recovery will be 73% with 75% first pass and 90% second pass recoveries (recovery would be 67.5% without recycle). 

Flux decreases with increasing feed concentration of dissolved solids. 

In general, most soil and rock minerals are electrical insulators (high resistivity) and, as a result, the flow of current is conducted primarily through the moisture-filled pore spaces within this matrix. Therefore, the resistivity of soils and rocks is predominantly controlled by the amount of pore water, the porosity and permeability of the system, and the concentration of dissolved solids in the pore water. 

A cooling tower handles 1000 gal/min (0.063 m3/s) of circulating water that is cooled from 110 to 80°F (316 to 300 K). How much blowdown and makeup are required if the concentration of dissolved solids is allowed to reach three times the concentration in the makeup ... 

If the evaporative/precipitation processes have a strong influence in the geographic zone, as in warm and arid zones, the dissolved salts derived from weathering and erosive processes become concentrated. This increases the ionic strength and the concentration of dissolved solids, thus increasing the sodium ion concentration. On the other hand, the calcium ion concentration decreases... 

Salinity is defined here as the grams of dissolved solids (or inorganic dissolved compounds) per kg of seawater, or parts per thousand (or as a per thou-sand%o). Alternatively, it can be defined as the mg/L or mmol/L of the major ions (i.e., those present in concentrations above 1 ppm). The total concentration of dissolved solids ranges from 7,000 ppm for the Baltic Sea, to an average of 35,000 ppm in large oceans, and up to 40,000 ppm in regions where evaporation is high and inputs are low, such as the Red Sea. 

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