Liquid chillers

Figure 11-19. Lithium bromide hermetic absorption refrigeration system, double effect, liquid chiller/heater. As shown in chilling mode, water is the refrigerant under low absolute pressure (boiling at 40°F) (Used by permission Cat. 521-606, form 16DF-1 PD, 1994. Carrier Corporation, a United Technologies Company.)...

The use of chilled water or a non-freeze solution for heat transfer is now replacing many applications where direct expansion of refrigerant has been used in the past. The method gives the advantage of using packaged liquid chillers. 

Artificial ice rinks are frozen shallow ponds, formed and maintained using a brine in tubes buried under the surface. Tubes may be steel or plastic for a permanent rink or plastic for a temporary installation. The brine temperature within the pipes will be about - 11°C, and must be lower for rinks in the open air, owing to high solar radiation loads. Packaged liquid chillers are now generally used, and will be transportable, complete with brine pumps and other apparatus, for temporary installations. 

Accu-Chill, Reclaims chiller heat for other use. Van Steenburgh Liquid Chillers, Inc. 

The kettle unit used in the reboiling service usually has an internal weir to maintain a fixed liquid level and tube coverage. The bottoms draw-off is from the weir section. The reboiling handled in horizontal thermosiphon units omits the disengaging space because the liquid-vapor mixture should enter the distillation tower where disengaging takes place. The chiller often keeps the kettle design but does not use the weir because no liquid bottoms draw off when a refrigerant is vaporized. 

The function of the evaporator will be to cool gas, liquid or other product load. In most cases air or a liquid is first cooled, and this is then used to cool the load. For example, in a coldroom air is cooled and this air cools the stored produce and carries away heat leaking through the structure in a water chiller system, the water is circulated to cool the load, etc. 

The pumps deliver the most accurate flow of the carbon dioxide if it is pumped in the liquid state. Since that is the case, if there is a great distance between the tank and the pump then a chiller is usually placed so that the tubing containing the carbon dioxide from the tank can be cooled maintaining the carbon dioxide in the liquid state. Most commercially available pumps operate at high enough pressures that the pump heads or pump bodies do not need ancillary cooling, but older models frequently required a chiller that provided a circulation of cold... 

The Phillips process is a two-stage crystallization process that uses a pulsed column in the second stage to purify the crystals (79,80). In the pulsed column, countercurrent contact of the high purity PX liquid with cold crystals results in displacement of impurities. In the first stage, a rotary filter is used. In both stages, scraped surface chillers are used. This process was commercialized in 1957, but no plants in operation as of 1996 use this technology. 

I Condensers 1 1 1 Liquid-to-vapor Heaters Coolers phase-change exchangers t Chillers... 

Pump could not maintain flow >0.8 ACFM CO was entering pump as gas instead of liquid Installed tubing insulation, heat exchanger and chiller... 

Hot-melt extrusion also requires other components to be scaled up in size as the extruder is scaled up in size. Typical components include multiple powder and liquid feeders, a chiller, a take-off cooling belt unit, and a control panel(s). Proper sizing of all components to achieve control of the process at each step is critical, especially because of the interrelationship of individual component feeds into the extruder and the resulting quality of the final extrudate. Variability on inputs translates into product variability on output from the extruder owing to its continuous principle of operation. 

Desiccant dehumidifiers reduce humidity in the air by using solid desiccant materials or liquid desiccant materials to attract and hold moisture. They can operate independent of chillers and can also be operated in series or parallel with chillers. Recoverable heat from the exhaust gases of turbines and engines for power generation or engine-driven chillers is used for regenerating desiccant material in these dehumidifiers. 

The thermodynamics of this process are described in detail in references (67 —72, 80,81). Let us examine a typical methanol injection system. In a typical methanol injection and recovery system for a cold-oil absorption or turboexpander plant, feed gas passes through a free-water knockout drum and into a gas-gas exchanger with methanol being sprayed on exchanger tube-sheets. Methanol inhibits hydrate formation and aqueous methanol condenses in the exchanger (and the chiller following it) and is pumped to a primary separator. The methanol-water solution is then flashed in a flash drum and filtered into a methanol still to recover methanol. Normally, methanol dissolves in the hydrocarbon liquids and is distilled as a mixture of propane and methanol. Some of the methanol is recovered as the overhead product to recover the methanol dissolved in the heavier solution, the bottoms of the methanol still (propane product or hydrocarbon liquids from the demethanizer)... 

Condensers Liquid-to-vapor phase-change Heaters Coolers Chillers... 

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