Determination dissolved solids

When the analyte is already present in a particulate form that is easily separated from its matrix, then a particulate gravimetric analysis may be feasible. Examples include the determination of dissolved solids and the determination of fat in foods. 

Blowdown discards a portion of the concentrated circulating water due to the evaporation process in order to lower the system solids concentration. The amount of blowdown can be calculated according to the number of cycles of concentration required to limit scale formation. Cycles of concentration are the ratio of dissolved sohds in the recirculating water to dissolved solids in the makeup water. Since chlorides remain soluble on concentration, cycles of concentration are best expressed as the ratio of the chloride content of the circulating and makeup waters. Thus, the blowdown quantities required are determined from... 

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... 

Total Solids None Total Solids is the sum of dissolved and suspended solids, determined gravimetrically See Dissolved Solids and Suspended Solids ... 

TDS total dissolved solids determined by evaporating the water and weighing the residue. Units are mg/l. 

The most important property of the dissolved solids in fresh waters is whether or not they are such as to lead to the deposition of a protective film on the steel that will impede rusting. This is determined mainly by the amount of carbon dioxide dissolved in the water, so that the equilibrium between calcium carbonate, calcium bicarbonate and carbon dioxide, which has been studied by Tillmans and Heublein and others, is of fundamental significance. Since hard waters are more likely to deposit a protective calcareous scale than soft waters, they tend as a class to be less aggressive than these indeed, soft waters can often be rendered less corrosive by the simple expedient of treating them with lime (Section 2.3). 

The effect of water salinity on crop growth is largely of osmotic nature. Osmotic pressure is related to the total salt concentration rather than the concentration of individual ionic elements. Salinity is commonly expressed as the electric conductivity of the irrigation water. Salt concentration can be determined by Total Dissolved Solids (TDS) or by Electrical Conductivity (EC). Under a water scarcity condition, salt tolerance of agricultural crops will be the primordial parameter when the quality of irrigation water is implicated for the integrated water resources management [10]. 

Aliquots of each treatment (root exudate) were dried at 105°C to determine total dissolved solids. The pH of each treatment was measured. 

Salinity is defined as the concentration of total dissolved solids (TDS) in a solution, usually expressed in mg/L. The TDS concentration in water is usually determined from the weight of the dry residue remaining after evaporation of the volatile portion of the original solution. Groundwater may be classified into four salinity classes64 ... 

Conditions in the dissolution medium, which, together with the nature of the dissolving solid, determine the dissolution mechanism (see Theories and Mechanisms of Dissolution, pp. 355-358). 

For wastewater samples, a number of additional solid determinations are typically performed, including total dissolved solids, volatile solids, and settleable solids. Total dissolved solids are the total solids minus the suspended solids and are determined in a manner similar to total solids, but after filtering out the suspended solids. Thus, a volume of the filtrate is measured into the evaporating dish and the water evaporated in a drying oven. 

Other process wastewater streams would provide the needed dilution for a once-through clear solution process. The total dissolved solids content of the combined waste should be determined to ensure that all discharge requirements can be met. 

A student wants to determine the enthalpy change associated with dissolving solid sodium hydroxide, NaOH, in water. The student dissolves 1.96 g of NaOH in 100.0 mL of water in a coffee-cup calorimeter. The initial temperature of the water is 23.4°C. After the NaOH dissolves, the temperature of the water rises to 28.7 C. 

The total solids concentration in parts per million is designated as C. In most cases, as in Table I, this is inferred from electro-metric determinations of conductivity, which respond only to dissolved solids. Usually, suspended solids are small. 

Each spray-dried droplet forms a single particle whose size is determined by the droplet size, the dissolved solids of the feed solution, and the density of the resulting solid particle. For a given formulation and process, both the solid content and density of the powder remain constant within a batch and from batch to batch therefore, the distribution of the primary particle size is determined by the droplet size distribution. A narrowly distributed particle size can be achieved with a well-designed atomizer and controlled process parameters. 

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). 

Quantitative Determination.— Dissolve. 1 gm. of pnlits.sinin cyanide in water and dilute to IOO cc. Dilute 10 ee, of this solution with 90 cc. of water, add a grannie of sodium chloride, and titrate with dcciriormal silver nitrate solid inn until a permanent, whitish turbidity appears. 

Figure 16-8 gives the density of oilfield brine at standard conditions as a function of total dissolved solids. The density at reservoir conditions is determined by dividing the density at standard conditions by the formation volume factor of the reservoir water at reservoir conditions. 

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. 

For example, a cooling tower with water containing four times as much total dissolved solids as its makeup supply would be operating at four cycles of concentration. The cycles of concentration are determined by the cooling tower design, water characteristics, operating conditions and the type of treatment system employed (cooling tower water treatment is discussed in detail in Chapter 8). 

Scaling results when the solubility limit of calcium carbonate is reached, at which point precipitation onto tube surfaces occurs. The extent of calcium carbonate precipitation is a function of the composition of the water and the temperature. The alkalinity, dissolved solids and f>H determine the scaling characteristics. Decreasing the pH by the direct addition of acid or by carbonization will decrease the scaling tendencies of the water within limits. If a water is on the scaling side of equilibrium, increasing the temperature will increase the scale deposition. 

NOTE Chloride ion is the usual analytical parameter used for determining cycles of concentration, but total dissolved solids or electrical conductivity are useful alternatives. 

Site-specific delivery will require the use of a self-locating system, typically a bioadhesive formulation, although an IVR, due to its elastomeric nature, will remain located high in the vaginal space. Conversely, for rapid distribution throughout the space, semisolid or fast-dissolving solid systems will be required. For semisolids, flow properties and viscoelastic character will be the critical determinants of their ability to spread rapidly from their point of application. 

The removal of Ra by adsorption has been attributed to ion exchange reactions, electrostatic interactions with potential-determining ions at mineral surfaces, and surface- precipitation with BaSO 4. The adsorptive behavior of Ra2+ is similar to that of other divalent cationic metals in that it decreases with an increase in pH and is subject to competitive interactions with other ions in solution for adsorption sites. In the latter case, Ra is more mobile in groundwater that has a high total dissolved solids (TDS) content. It also appears that the adsorption of Ra + by soils and rocks may not be a completely reversible reaction (Benes et al. 1984, 1985 Landa and Reid 1982). 

This is an easy and short method that does not require distillation of the sample. It is applicable when the CN concentration is less that 0.3 mg/L. For higher concentration, dilute the sample. This method determines the HCN and cyanide complexes that are amenable to chlorination. Thiocyanate is positive interference in this test. High concentration of total dissolved solids (greater than 3000 mg/L) may affect the test result. To compensate for this, add an equivalent amount of NaCl in NaOH solution. 

The total dissolved solids (TDS) in aqueous samples is determined by filtering an aliquot of the sample, evaporating the filtrate to dryness in a weighted dish, and then measuring the weight of the dried residue to a constant weight. The residue is dried at 180°C at least for an hour. 

Solubilities of annealed skeletal carbonates were estimated by Land (1967) by allowing the system to reach a steady state pH and by determining dissolved Ca2+ and Mg2+ concentrations. Dissolution of the magnesian calcites in Land s experiments appeared to be congruent in the sense that the steady state solution had a molar Ca2+/Mg2+ ratio similar to that of the solid. 

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. 

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