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Evaporative cooling condensers

Evaporative-cooled condensers in many applications give greater heat transfer than air-cooled or water-cooled condensers. The evaporative equipment can do this by offering a lower temperature sink. Evaporative-cooled condensers are frequently called wet-surfece air-coolers. Perhaps the best description for this type of equipment is a combination shell-and-tube exchanger and cooling tower built into a single package. The tube surfaces are cooled by evaporation of water into air. [Pg.512]

Evaporative-cooled condensers in many applications give greater heat transfer than air-cooled or water-cooled condensers. The evaporative equipment can do this by offering a lower temperature sink. [Pg.143]

The evaporative-cooled condenser is basically a water-saving device. From a heat transfer standpoint, the performance of the evaporative-cooler is influenced only by the wet-bulb temperature and the density of the air entering the cooler. [Pg.144]

Perhaps the greatest advantage of the evaporative cooler is a lower temperature heat sink (the wet-bulb temperature of the air). With some overlap in operating temperatures, the evaporative cooler has application where the aircooled equipment must drop out of the picture. The evaporative cooler has limited use for process temperatures above 75°C because high tube-wall temperatures result In rapid buildup of scale on the tubes. In most cases, the evaporative-cooled condenser has application when process temperatures are between 75°C and 5°C above the design wet-bulb temperature of the ambient air. [Pg.144]

A simple form of apparatus is that in which a cooled condensing surface is supported a few cm. above a shallow, heated pool of liquid, and the whole is enclosed in a highly evacuated chamber (compare Fig. II, 26, 1) this offers the least hindrance to the flow of vapour from the evaporating to the condensing surface. The rate of distillation is then determined by the rate at which the liquid surface is able to produce vapour. When the evaporating... [Pg.120]

Relative humidity at which water condenses on the apphed film as a result of evaporative cooling effects. [Pg.274]

Evaporative condensers (Fig. 11-88) are widely used due to lower condensing temperatures than in the air-cooled condensers and also lower than the water-cooled condenser combined with the cooling tower. Water demands are far lower than for water-cooled condensers. The chemical industry uses shell-and-tube condensers widely, although the use of air-cooled condensing equipment and evaporative condensers is on the increase. [Pg.1113]

Air-cooled condensers are similar to evaporative in that the service dic tates either the use of more expensive alloys in the tube construction or conventional materials of greater wall thickness. [Pg.1114]

Absorber is a component where strong absorber solution is used to absorb the water vapor flashed in the evaporator. A solution pump sprays the lithium bromide over the absorber tube section. Cool water is passing through the tubes taking refrigeration load, heat of dilution, heat to cool condensed water, and sensible heat for solution coohng. [Pg.1118]

The solution in the left flask is stirred for 30 minutes after all the potassium amide has been added. The nitrogen inlet is briefly removed and 120 g. (1.5 moles) of ammonium nitrate is added this discharges the ehartreuse color. (Caution Vigorous foaming occurs.) Ethyl ether (500 ml.) is added and the dry iee condenser is replaced by a standard water-cooled condenser. I he ammonia is evaporated by allowing the stirred reaction mixture to warm to room temperature this takes several hours iti(l it is convenient to have it occur overnight. [Pg.3]

For the convenience of users, the refrigerating effect of compressors is usually tabulated (Table 4.1) or given in graphical form (Figure 4.19), and is shown as the net cooling capacity based on the evaporating and condensing temperatures or pressures. Such published data will include absorbed power and indicate any limitations of the application. [Pg.56]

Example 6.4 A small water-cooled condenser uses mains water at 13°C and heats this to 24°C before it goes to waste. The evaporator duty is 4.2 kW and the motor output is 1.7 kW. What is the water mass flow ... [Pg.69]

Ambient dry bulb temperature for air-cooled condensers Available water temperature for water-cooled condensers Ambient wet bulb temperature for evaporative types... [Pg.75]

In most climates the wet bulb temperature is well below the dry bulb temperature and there is an advantage in using water or evaporative cooling for larger plant. These options need to be investigated and compared. The present concern over spray-borne diseases may indicate a preference for air cooling in the vicinity of institutions but correct maintenance of water cooling towers and evaporative condensers will permit their use elsewhere. Table 10.2, based on the tentative temperature differences of 15 K and 12 K... [Pg.125]

Air-cooled condensers require a large air flow for a given heat rejection duty and the limitation on their use is reached on account of their size and the need to get enough air. Water or evaporative cooling should always be considered as a possibility, except for smaller sizes or where using packaged condensing units. [Pg.126]

Such assemhlies might have the compressor and drive only, for site connection to a remote air-cooled condenser. As such, they are correctly termed compressor units. Compressor and condensing units will he site connected to evaporators, and these components must he matched in capacity (see Chapter 10). [Pg.155]

Example 13.1 In the rating curves for an air-cooled condensing unit shown in Figure 13.3, what is the cooling capacity at an evaporating temperature of - 25°C and with air onto the condenser at 25°C By how much does this drop with condenser air at 35°C ... [Pg.155]

Example 13.2 In the rating table shown in Table 13.1 for a water-cooled condensing unit, what is the cooling duty at -20°C evaporation, with water onto the condenser at 25°C ... [Pg.155]

Example 35.4 An air-cooled condensing unit is rated at 13.7 kW on R.22 when evaporating at 5°C and with ambient air at 43°C. Estimate the duty with ambient air at 52°C. [Pg.359]


See other pages where Evaporative cooling condensers is mentioned: [Pg.143]    [Pg.143]    [Pg.2456]    [Pg.2473]    [Pg.365]    [Pg.225]    [Pg.459]    [Pg.521]    [Pg.378]    [Pg.55]    [Pg.356]    [Pg.475]    [Pg.1108]    [Pg.1147]    [Pg.2184]    [Pg.65]    [Pg.218]    [Pg.94]    [Pg.414]    [Pg.301]    [Pg.306]    [Pg.81]    [Pg.124]    [Pg.144]    [Pg.360]    [Pg.76]    [Pg.12]    [Pg.569]   


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