Pass-through

Perform general operational controls verification testing. 

Operate system throughout the range of operating design specifications or range of intended use. 

Verify that both doors of the pass-through cannot be open simultaneously. 

Verify that directional air flows are consistent with design drawings by verifying relative differential air pressures. 

Verify air flow patterns by performing smoke-stick air flow studies and recording the test on videotape. 

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In situations where a low concentration of suspended solids needs to be separated from a liquid, then cross-flow filtration can be used. The most common design uses a porous tube. The suspension is passed through the tube at high velocity and is concentrated as the liquid flows through the porous medium. The turbulent flow prevents the formation of a filter cake, and the solids are removed as a more concentrated slurry. 

Both vacuum operation and the use of refrigeration incur capital and operating cost penalties and increase the complexity of the design. They should be avoided if possible. For a first pass through... 

Tunnel dryers are shown in Fig. 3.15a. Wet material on trays or a conveyor belt is passed through a tunnel, and drying takes place by hot air. The airflow can be countercurrent, cocurrent, or a mixture of both. This method is usually used when the product is not free flowing. 

It is thus recommended that in a first pass through a design, thermal coupling should not be considered. Rather, simple columns should be used until a first overall design has been established. Only when the full heat-integration context has been understood should thermal coupling be considered. 

If air (or oxygen) and steam are both passed through a high-temperature bed of coal or coke these reactions can be balanced, thus controlling the bed temperature and the fusion of the ash. In the higher pressure Lurgi process the gas obtained is high in methane, formed in reactions such as... 

Hall effect If a current (I) is passed through a conducting crystal in a direction perpendicular to that of an applied magnetic field (H), the conductor develops a potential (V) between the faces which are mutually perpendicular to both the direction of the current and the magnetic field. This is known as the Hall effect the magnitude of the potential difference is given by... 

Miblimation The volatilization of a solid substance into the vapour phase without passing through the liquid phase. Also used to describe the process of purification in which the vapour is condensed directly from the vapour phase to a solid (on a cold-finger often cooled by refrigerant). In the latter case this substance may melt during the initial vaporization. Used for purification. 

In this case, a preliminary separation will have taken place either in the plant by stabilization, or by the chromatograph which will have had a prefractionating column. This column will isolate the components having boiling points higher than pentane, allowing only the noncondensable hydrocarbons and a fraction of the pentanes to pass through to the analytical column. 

Table 4.19 gives the Henry constants for a few common gaseous components. The chemical nature is also a dominant factor. The effect of temperature is moderate note that the solubility passes through a minimum that depends on the hydrocarbon in question and that it is around 100°C. 

The cold filter plugging point (CFPP) is the minimum temperature at which a given volume of diesel fuel passes through a well defined filter in a limited time interval (NF M 07-042 and EN 116 standards). For conventional diesel fuels in winter, the CFPP is usually between —15 and —25°C. 

Fuel passing through certain hot zones of an aircraft can attain high temperatures moreover it is used to cool lubricants, hydraulic fluids, or air conditioning. It is therefore necessary to control the thermal stability of jet fuels, more particularly during supersonic flight where friction heat increases temperatures in the fuel tanks. 

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