Cold discharge

Cold discharge (under 100 °C) Micro surface etching Surface cleaning... 

Fig. 7. Plant for spray-drying of detergents and soaps. 1, Burner 2, air combustion 3, cold air fan 4, hot air generator 5, spray-drying tower 6, cleaning ring 7, no22les circuit 8, tower suction cyclones group 9, tower suction fan 10, double-flap dischargers 11, recovery powder cyclone 12, recovery powder fan 13, belt conveyor 14, air lift 15, air lift suction cyclones 16, air lift suction fan 17, double-flip dischargers 18, vibrating sieve.

Cold inlet or hot discharge at the middle of the case reduces oil-seal and lubrication problems. 

These mechanisms can be observed in many common situations. For example, fog via mixing can be seen in the discharge of breath on a cold day. Fog via adiabatic expansion can be seen in the low-pressure area over the wing of an airplane landing on a humid summer day and fog via condensation can be seen in the exhaust from an automobile air conditioner (if you follow closely enough behind another car to pick up the ions or NO molecules needed for nucleation). All of these occur at a veiy low supersaturation and appear to be keyed to an abundance of foreign nuclei. All of these fogs also quickly dissipate as heat or unsaturated gas is added. 

There is a Second Law thermodynamic advantage in operating an expander at as low a temperamre as possible. In most applications it has been aiTanged to discharge just above tlie dew point of tlie expanded gas. If the cold compressed gas could enter tlie expander at or near its dew point, the expander would then operate condensing and at the lowest possible temperamre. Such condensate has traditionally been troublesome in turbines, but tliis has been solved in modern turboexpanders. 

Where Water Hammer Occurs. Water hammer can occur in any water supply line, hot or cold. Its effects can be even more pronounced in heterogeneous or biphase systems. Biphase systems carry water in two states, as a liquid and as a gas. Such a condition exists in a steam system where condensate coexists with live or flash steam in heat exchangers, tracer lines, steam mains, condensate return lines and, in some cases, pump discharge lines. 

The thermosyphon is a good system for remote areas where utilities are limited, but requires some careful design to ensure proper operation. This is a circulating system with the motive force derived from the change in densiiy of the cooling fluid from the hot to the cold sections of the sysieni. API dl8 pennits this system for discharge gas temperatures below 210 F or a temperature rise across the compressor of 150°F or less. 

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