Tank studies

Relatively uncomphcated transparent tank studies with tracer fluids or particles can give a similar feel for the overall flow pattern. It is important that a careful balance be made between the time and expense of calculating these flow patterns with computational flirid dynamics compared to their apphcabihty to an actual industrial process. The future of computational fluid dynamics appears very encouraging and a reasonable amount of time and effort put forth in this regard can yield immediate results as well as potential (or future process evaluation. 

The depolymerized Nylon used in the hydrogenation process was obtained by the ammonolysis of a mixture of Nylon-6 and Nylon-6,6 (described elsewhere, see reference 2). Hydrogenation reactions were conducted in 300 cc stirred pressure vessels. For semi-batch reactions hydrogen was constantly replenished to the reactor from a 1L reservoir to maintain a reactor pressure of 500 psig and all of the reactions were conducted with the same operating parameters and protocol. In continuous stirred tank studies hydrogen flow was controlled using... 

A technique which can assist in the scale-up of commercial plants designs is the use of scale models. A scale model is an experimental model which is smaller than the hot commercial bed but which has identical hydrodynamic behavior. Usually the scale model is fluidized with air at ambient conditions and requires particles of a different size and density than those used in the commercial bed. The scale model relies on the theory of similitude, sometimes through use of Buckingham s pi theorem, to design a model which gives identical hydrodynamic behavior to the commercial bed. Such a method is used in the wind tunnel testing of small model aircraft or in the towing tank studies of naval vessels. 

In water tank studies Willis and DeardorfF (1978) found a = 0.82. 

Relatively uncomplicated transparent tank studies with tracer fluids or particles can give a similar feel for the... 

Most laboratory-based calibration experiments are conducted under controlled conditions, with constant concentrations of metals in clean water. This does not necessarily reflect field conditions, and there is uncertainty as to how laboratory estimates of calibration parameters will transfer to the field, where concentrations of metals can fluctuate over several orders of magnitude. Fluctuations are often a result of an accidental discharge or weather event, and they can be accompanied by changes in, for instance, levels of dissolved and particulate organic material, pH and redox conditions. It is difficult to reproduce these conditions in the laboratory, but the use of tank studies where conditions can be controlled, and defined patterns of changing pollutant concentration can be achieved could provide a solution, and provides a compromise between the use of routine laboratory-based calibration, and the use of a reference site. 

Wave tank study of phase velocities and damping of gravity-capillary wind waves in the presence of surface films... 

Steam generator PGN-200M (model of the BN-600 reactor steam generator) has been in operation generating steam for 15 160 hours. It was decommissioned because of inter-circuit leak. This leak was revealed by detectors of hydrogen in the argon cover gas of pressure compensatory tank. Studies have revealed ingress of 3 kg of water into the secondary sodium... 

Fig. 1. CTC as a compliance enhancer . Pie chart from a US hospital think tank study showing that among patients having virtual colonoscopy 60% had never had any prior colon cancer screening...

Figure 13-34 Yields in four stirred vessel sizes. The 19 and 65 L tanks were studied by Baldyga and Bourne (1992) feed points were at the impeller tip and midway between the tip and the tank wall. In the 100 and 1000 gal (378 and 3780 L, respectively) tanks studied by Paul (1988), the feed points were all at the impeller blade tips. In both cases a Bourne reaction of the form A + B R R + B S was used.

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