Applications—High Pressure

Fully enclosed—used for high head, high pressure applications. 

Generally used In air applications or applications where moderate leakage is tolerable. Normally not used in high pressure applications. 

Applications where positive sealing is desirable and only small amount of buffering gas leakage tolerable. Not suitable for very high speed or very high pressure application. Only gases may be used for buffering. 

Oxygen scavenger substances may, in some high heat flux and high pressure applications, decompose to yield corrosive components. Applications should be individually assessed with the supplier concerned. 

By virtue of their construction, diaphragm pumps cannot be used for high pressure applications. In the Mars pump, there is no need for a diaphragm as the working fluid (oil), of lower density than the liquid to be pumped, forms an interface with it in a vertical chamber. The pump, which is used extensively for concentrated slurries, is really a development of the old Ferrari s acid pump which was designed for corrosive liquids. 

An interesting example is photodimerization of waphorone where the use of SC CO2 increases the yield of the aaft -dimer relative to the yn-dimer. Special polymers ean be made by using SC fluids. Apart from SC CO2, SC propane can be very useful and act as a convenient medium. Roche has also reported replacement of an expensive Rh catalyst with a cheaper Ru catalyst using a high-pressure application of hydrogen. 

Aq, Aqueous C, cementing Cb, clay based D, drilling fluids FF, fracturing fluids HP, high pressure application HT, high-temperature application LT, low temperature Ob, oil based S, seawater mud SB, salt and brine tolerant. 

Fatty acid amides of isophorone diamine, 2,5-diaminonorbomylene, and 2,2,4-trimethyl-1,6-diaminohexane are particularly suitable for high-tempera-ture and high-pressure applications [971],... 

Commercial products, high pressure applications in, 13 436-438 Commercial-scale pharmaceutical operations, 13 733-736 in-process controls in, 18 734 processing equipment requirements in, 18-733-734... 

High performance sealants, 22 28 High phosphorus alloys, corrosion performance of, 9 710-711 High pinning Type II superconductors, 23 High pressure apparatus, 13 413 High pressure applications, 13 436-448 in commercial products, 13 436-438 in inorganic chemistry reactions, 13 440—448... 

Inorganic chemistry reactions high pressure applications in, 13 440-448... 

Good for high-temperature and high-pressure applications... 

Table 1.4-1 gives a summary about high pressure applications, exhibiting the methods, the pressure levels applied, and the products or results of the processes involved. The survey is not complete, as the development is changing and progressing permanently. 

A well know design strategy is summerized by the remarkable sentence "Leakage Before Rupture", which means that tough materials must be selected and local embrittle-ments due to the three-dimensional stress-distributions involved should be avoided for high pressure applications. 

The temperature measurement devices which do not contact the hot surfaces, for example, optical -, radiation pyrometers, and infrared techniques, are not typical for high-pressure application. 

In high-pressure applications these are two main trends of research high hydrostatic pressure treatment (2000-7000 bar) and supercritical CO2 treatment. In both cases the aim is to inactivate the micro-organisms in order to protect and preserve foods, and so to prolong their shelf-life. 

Some of their methods have been commercialized by hte AG, a German supplier of services in combinatorial catalysis. High-pressure applications have not been reported often due to their expense. A 14-fold stirrer autoclave has recently been presented [34] for liquid-gas reactions. 

Figure 3.46 Two types of hollow-fiber modules used for gas separation, reverse osmosis, and ultrafiltration applications. Shell-side feed modules are generally used for high-pressure applications up to 1000 psig. Fouling on the feed side of the membrane can be a problem with this design, and pretreatment of the feed stream to remove particulates is required. Bore-side feed modules are generally used for medium-pressure feed streams up to 150 psig, for which good flow control to minimize fouling and concentration polarization on the feed side of the membrane is desired...

For high-pressure applications in the hydrocarbon and chemical processing industries, a titanium compact heat exchanger has been developed by Rolls-Laval. This heat exchanger consists of diffusion-bonded channels that are created by superplastic forming of titanium plates (18). This heat exchanger can handle high pressure and corrosive fluids and is suitable for marine applications. 

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