Refrigeration plant

C. It occurs in natural gas. May prepared by reduction of ethene or ethyne by hydrogen under pressure in the presence of a nickel catalyst, or by the electrolysis of a solution of potassium elhanoate. It has the general properties of the paraffins. Used in low-temperature refrigeration plant. 

Cracks detection in the compressor equipment and power facilities, assemblies, pipes, separators, metalworks, heating installations and refrigerating plants. 

Uses of the polyamide-imides include pumps, valves, gear wheels, accessories for refrigeration plant and electronic components. Interesting materials may be made by blending the polymer with graphite and PTFE. This reduces the coefficient of friction from the already low figure of 0.2 (to steel) to as little as 0.02-0.08. 

Typical applications include heat rejection from the refrigeration plant. The highest proportion of cooling takes place by evaporation. 

The arrangement for closed recirculation is shown in Fig. 4.40. It overcomes many of the problems encountered with the open system. Typical applications include engine cooling and heat rejection from refrigeration plant. 

In work areas, the noise is usually generated by different sources, such as air-handling units, refrigerating plants, etc. (especially extract and supply air fans). 

Chilled water Water that is cooler than ambient temperature, obtained from a refrigeration plant, cooling tower, or a well. 

Cooling water Water used as the cooling medium in refrigerating plant condensers. It may be from a well or river or recooled. 

In a refrigeration plant the inlet gas is cooled to a low enough temperature to condense the desired fraction of LPG and NGL. Either freon or propane is used as the refrigerant. Figure 9-2 shows a typical refrigeration plant. 

Figure 9-2. Simplified flow diagram of a refrigeration plant.

These are higher than for a lean oil plant. It is possible to recover a small percentage of ethane in a refrigeration plant. This is limited by the ability to cool the inlet stream to no lower than -40°F with normal refrigerants. 

Most refrigeration plants use freon as the refrigerant anti limit the lowest temperature to -20°F. This is because the ANSI piping codes require special metallurgy considerations below -20 F to assure ductility. 

If the pressure on a liquefied gas is reduced, some of the liquid evaporates, and the rest gets colder. All refrigeration plants, domestic and... 

Reflux drum Mixer or stirrer Breathing apparatus (BA) Slip-plate Refrigeration plant Knock-on (or domino effects) Nonreturn valve Blinded... 

Let me tell you how things were in the heady days of the late 1960s, when scientists (like me) and engineers first got their hands on computers. Computers were very large beasts, and they consumed very many kilojoules (kilocalories in those days, or if you are a North American reader) per unit time. If you believe in the law of conservation of energy, you will understand why such machines had a refrigeration plant, where the three resident engineers kept the milk for their coffee. 

Kalte,/. cold, coldness, chill, -anlage,/. refrigerating plant, -anwendung,/. employment of cold, refrigeration, -bad, n. cold bath, cooling bath. 

Kiihl-anlage, /. cooling plant, refrigerating plant, -apparat, m. cooling apparatus cooler refrigerator condenser, -bottich, m. cooling tub, cooler. 

Table 11-1 presents a few of the many possible operating conditions for these systems. The same refrigerating plant may operate through a wide range of pressures and temperatures. Table 11-2 presents a summary of utilities required for absorption plants. The steam indicated can be substituted by direct gas, waste heat, or other stream at an equivalent temperature level. 

All electrical energy fed to the room will appear as heat. This presents a load to the plant unless power is conveyed out of the room by cable or hot items are physically removed. Parts of some large computers are cooled by a direct supply of chilled water presenting a load on the refrigeration plant but reducing the load on the airside. Cold outside conditions will result in some of the internal load being met by fabric loss. 

When temperature limitation is more important than close control of conditions, a considerable economy of refrigeration plant operation results from arranging to draw... 

To handle a peak cooling load with a reduced size of refrigeration plant, typically to make ice over a period of several hours and then use ice water for the cooling of a batch of warm milk on a dairy farm. This is also used at main creameries, to reduce peak electricity loads. The available water is very close to freezing point, which is the ideal temperature for milk cooling. 

Pipes buried in the structural slab. These are connected to delivery and return headers, and glycol circulated. This is heated by waste heat from the refrigeration plant. Steel pipe should not be used under the floor unless protected against corrosion. Air vent pipes to allow a current of ambient air through the ground under the base slab. This is not very suitable in cold climates. 

Dairy farms have bulk-storage tanks with their own refrigeration plants. These are usually made in the form of a double-skin, insulated tank, having the evaporator coils in the jacket, which also contains water. The refrigeration system runs throughout the 24 hours and... 

Example 21.7 The milk-cooling requirement (above) of 700 litre/h is a maximum rate. There is no need to allow for any more than this, but it cannot be any less. Alternatively, this could be cooled using an ice bank, in which case the total load of 2400 litre could be spread over 16 h of running time. With an allowance for water tank insulation heat gains and an ice water pump, the load might be reduced to a refrigeration plant one-third the size. 

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