Process dilution

If the viscous bitumen in a tar sand formation can be made mobile by an admixture of either a hydrocarbon diluent or an emulsifying fluid, a relatively low temperature secondary recovery process is possible (emulsion steam drive). If the formation is impermeable, communication problems exist between injection and production weUs. However, it is possible to apply a solution or dilution process along a narrow fracture plane between injection and production weUs. 

The decrease in free energy (—AG) which provides the driving force in a cell may ensue either from a chemical reaction or from a physical change. In particular, one often studies cells in which the driving force is a change in concentration (almost always a dilution process). These cells are called concentration cells. The alteration in concentration can take place either in the electrolyte or in the electrodes. As examples of alterations in concentration in electrodes, mention may be made of amalgams or alloy electrodes with different concentrations of the solute metal and in gas electrodes with different pressures of the gas. 

When the temperature of 3He returning to the MC is higher than the MC temperature for more than about a factor 3, the dilution process does not work. Equation (6.13) clearly shows the importance of having efficient heat exchangers. For example, if h3 = 100 p,mol/s and the power demanded to the MC is 1 xW, we get ... 

The mixture has 20% 3He concentration. Only 6.7% is used in the cooling point, so that the dilution process extracts additional power in the return line until the J-T expansion (see Fig. 6.17). 

Let us note that below 50 mK, the cooling power of Pomeranchuk process is larger (two orders of magnitude at 2mK) than that of the dilution process. In Fig. 7.3, the comparison between the two methods is reported. 

Ordinary all-purpose household cleaner is sold in concentrated liquid form, and requires dilution by consumers before application. This potentially causes either wastage or overdosing as the consumer is left alone to judge the correct amount of detergent to use. In addition, acid/alkali bums for consumers are not uncommon during the dilution process. Hence a demand for a more convenient product is apparent in the market. 

A synthetic organic chemicals plant discharges mainly two types of waste streams, namely strong process waste and dilute process waste. The flow and BOD5 of the waste streams are given in the following table. 

There are two main sources of error propagation in static measurements, errors due to successive dilutions and errors due to initial instrument offset. Other errors which are also applicable to SEC analysis are discussed in (J ). These errors can be propagated using the criteria presented here. If w is the intial mass of polymer and Vj is the amount of solvent added to obtain the desired concentration Ci, the dilution process can be represented by the following set of equations ... 

The net flow of solvent into the solution will continue unless a pressure equal to II is applied in the reverse direction (for example, as a result of the buildup of a hydrostatic head on the solution side of the membrane as the dilution process proceeds). Indeed, if a pressure greater than II is deliberately applied on the solution side, the net flow of solvent will be out of the solution and into the pure solvent (Fig. 14.2b). This is reverse osmosis, which obviously can be used to derive pure water from solutions. The semipermeable membrane must be able to withstand a substantial pressure differential, as well as to resist passage of ions and other solutes... 

The raw juice exiting the diffuser is a murky dark gray solution occluded by colloidal materials from the ruptured beet tissue, small pieces of cossettes, and fine soil that escaped the fluming and washing processes. It is microbiologicaUy and chemically unstable and unsuitable for concentration and crystallization. Common parlance assigns juice to more dilute process streams and syrup (or occasionally liquid) to steams with solids concentrations... 

Dilution. It is important to be aware that the dilution process utilized by the automated workstation may differ from a manual process. Adjustments in dilution factors may be required and considerations of the density value of the diluting solvent and sample filtrate are valuable. In some cases the dilution step can be avoided when designing the automated sample preparation through initial volume adjustment whenever possible and/or through changes in the injection loop size to achieve proper column loading. 

Differences in mutagenic activity occur between the various locations. Local conditions may enhance self-purification processes of the river. Dilution processes play an important role, as is shown for Lake IJssel and the North Sea coast. 

First, any material added to a process solution other than pure water or replenishment chemistry must be considered at least a potential contaminant, requiring later removal through purification or solution disposal. Therefore, adding tap water to a process solution, when replacing evaporative losses with either "fresh" water or captured rinses containing diluted process chemistry, hastens the demise of that solution, thereby increasing waste generation. 

High-sensitivity instrumentation is employed to assure the purity of the parent gases used to prepare the standards, to ensure that no chemical or physical reactions take place during any stages of the preparation and dilution process, and to demonstrate the longer-term stability of the standards after preparation. Two main types of instrument aTe used ... 

If in Figure 53.1(b) an additional pressure is exerted (= 77) on the solution (right-hand side) of the diagram then the influx of pure solvent into the solution (and the dilution process) is halted. This additional pressure is called the osmotic... 

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