Condensate receiver

Batch distillation equipment can range from a free-standing column with a reboiler, condenser, receiver, and vacuum system, to the use of a jacketed reactor with a condenser. Distillation often involves the generation of combustible vapors in the process equipment. This necessitates the containment of the vapor within the equipment, and the exclusion of air from the equipment, to prevent the formation of combustible mixtures that could lead to fire or explosion. 

Establish condensate receiver (or flash tank) pressure, psig. 

Referring to Figure 2-54, enter at steam pressure of (1) above, move horizontally to condensate receiver pressure of (6) above, and then up vertically to the factor scale. ... 

When the sum of the partial pressures of the steam and the material distilled reach the system pressure, boiling begins and both components go overhead in the mol ratio of their partial pressures. Upon condensation of the overhead mixture, the condensate receiver will contain two layers that can be separated by gravity. 

The distance of D between the two parts of the curve indicates the proportion of flash gas at that point. The condenser receives the high-pressure superheated gas, cools it down to saturation temperature, condenses it to liquid, and finally suhcools it slightly. The energy removed in the condenser is seen to he the refrigerating effect plus the heat of compression. 

With ammonia, oil sinks to the bottom and does not go into solution with the refrigerant. Ammonia condensers, receivers and evaporators can be distinguished by the provision of oil drainage pots and connections at the lowest point. Automatic drainage and return of the oil from these would have to depend on the different densities, and is veryrarely fitted. The removal of oil from collection pots and low-point drains is a periodic manual function and is carried out as part of the routine maintenance. The halocarbons are all sufficiently miscible with oil to preclude the possibility of separate drainage in this way. 

In considering smaller steam-generating plants, a low-level (returning) condensate receiver also may double as a FW tank by providing the entry point for MU water. 

The condensate return system is a post-boiler section system that includes all steam traps, condensate lines, associated manifolds and valves, condensate receiving tanks, save-all tanks, condensate pumps, and other auxiliaries for condensate recovery. 

When systems are poorly designed, with unlagged condensate receiver and FW tanks open to the atmosphere, thus permitting loss of heat (colder water holds more oxygen) and permanent contact with air. (This vent point is commonly employed for the addition of chemical treatment.)... 

Under these conditions, the tendency is to try to compensate as quickly as possible for the loss of inhibitor and either add treatment directly to the condensate receiver, FW tank, or FW pump. This usually is not a good idea because in many cases the physically compact FT boiler design is insufficiently forgiving and problems of surging (priming) and foaming occur. This typically leads to carryover of BW and also the development of water hammer. 

Where the MU water supply to cast-iron boilers does not precisely keep up with steam generation demands, the water level can quickly decrease and the problems become even more acute. Conversely, where MU does precisely keep up with steaming rates and is supplied to a common condensate receiver-FW tank via automatic level control, the tank can easily overfill when condensate finally drains back under on-off operating conditions. This gives rise to a loss of valuable hot, treated water from the system and the start of another chain of cause and effect problems. 

In smaller boiler systems, the FW tank often acts as a common condensate receiver, MU water heater, and deaerating vessel. As such, the tank is subject to the same corrosion problem risks that befall deaerators, economizers, and FW lines. Smaller systems often are inadequately designed and constructed, with the result that they may suffer serious oxygen corrosion in a particularly short time. (It is not unknown for tank wall perforation to occur within 3 to 6 months of the installation of a new FW tank as a result of pitting corrosion.)... 

All efforts should be made to eliminate these kinds of operating practices. Thus, where condensate receivers are fully open to atmospheric pressure (vented), efforts should be made to limit the absorption of oxygen at the water surface by raising the water level (where horizontal cylindrical tanks are used) or by covering the water surface (thermally resistant plastic balls are sometimes employed). 

The presence of red ferric oxide usually indicates an inactive pit but black oxide infers active pitting. Condensate receivers are common points for oxygen infiltration (especially in smaller boiler plants). 

Maintaining condensate temperatures at or near saturation points to minimize carbonic acid formation. This includes heating intermediate condensate receivers to maximum practical temperatures. 

In large and extensive industrial process plants, it is not unusual to find unvented condensate receivers or reboilers at the end of a long steam-condensate line. These vessels tend to act as collection and storage points for carbon dioxide, which may redissolve in condensate. These satellite stations should be vented and receive an amine booster feed. 

Condensate return pumps and condensate receivers are likely candidates for mechanical malfunction, especially in vacuum systems. 

Other pieces may have to be elevated to enable the system to operate. A steam jet ejector with an intercondenser that is used to produce a vacuum must be located above a 34 ft (10 m) barometric leg. Condensate receivers and holding tanks frequently must be located high enough to provide an adequate net positive suction head (NPSH) for the pump below. For many pumps an NPSH of at least 14 ft (4.2 m) H2O is desirable. Others can operate when the NPSH is only 6 ft (2 m) H2O. See Chapter 8 for a method of calculating NPSH. 

The conditions of the reactions are such that during the co-condensation the co-condensate receives radiation from the molten metal sample which is comparable to a 1KW tungsten lamp. 

The sketch below shows a distillation column that is heat-integrated with an evaporator. Draw a conirot concept diagram which accomplishes the following Directives (a) In the evaporator, temperature is controlled by steam, level by liquid product, and pressure by auxiliary cooling or vapor to the rcboiler. Level in the condensate receiver is controUed by condensate. 

The acetoxime may be distilled by direct heating rather than by injection of steam when the prescribed quantities are taken, however, it will be found that the liquor becomes saturated with sodium sulfate at a point just before the expulsion of the oxime is complete, so that addition of water during the distillation is necessary. More rapid distillation can be obtained by the use of a current of steam, especially if a condensing receiver (Vol. II, pp. 80-82) be employed. The oxime can also, if desired, be isolated for hydrolysis by separation of the oily layer and extraction with benzene the resulting crude hydroxyl-amine hydrochloride is, however apt to be dark in color and to contain inorganic salts. 

Apparatus. All vapor-liquid equilibrium measurements were made by using a modified Othmer still provided with an external electric heater. Total volume of the still was about 500 cm3, of which about 300 cm3 was occupied by liquid. The liquid loaded in the condensate receiver was about 7 cm3. Details of the still are described in a previous paper (5). 

The compressor, motor, condenser, receiver, and letdown valve are all components of your home central air-conditioning unit. They are installed as a package, surrounded by the condenser, outside your house. The evaporator is located in your attic. To continue our description of the process flow ... 

These designs have provisions for the removal of noncondensable vapors and air, for the prevention of freezing during cold weather. Excessive buildup of noncondensable vapors in the main condenser would prevent effective condensation. Protection against ice formation is usually accomplished by warm air recirculation and/or fan control. Condensed steam from cooling coils flows by gravity to condensate receivers and is pumped back to the feedwater circuit by a condensate pump. 

Simple stage An equilibrium stage that contains no feeds, side products, or heat exchangers (top condenser/receiver, bottom reboiler, interreboiler, or intercondenser). 

The liquid product in the main liquid receiver was combined with the organic phases in the condenser receivers. The two water layers were combined also. 

When the addition of dimethyl sulfate Is complete, stirring was continued for 1 hour at 20-25 C. Then the temperature was raised to 60-65 during 10 minutes and was kept at this value until the evolution of carbon dioxide ceased. After the addition of 25 ml of cold water, the reaction flask was cooled rapidly In an Ice bath and 10 ml of ethanolamlne was added. The resultant crystalline slurry was removed from the flask and the apparatus was rearranged using a distilling condenser, receiving flask, and a heating bath. 

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