Condensation “steam

Complementary to the matter of wetting is that of water repellency. Here, the desired goal is to make 6 as large as possible. For example, in steam condensers, heat conductivity is improved if the condensed water does not wet the surfaces, but runs down in drops. 

During this process some water will have condensed in the steam-trap D and also in the distillation bulb F. If at the end of the steaming-out process, the Bunsen burner is removed from the generator A, the pressure in A will be reduced owing to steam condensation, and the liquid in F will be sucked back into D provided that the benL-over tube is carefully adjusted, the bulb F may be almost completely emptied of liquid as desired. Finally the condensed water in the steam-trap D may be run out by op ing the tap Tj. 

Ak ammonia piping should be standard (Schedule 40) or extra heavy (Schedule 80) steel having welded or screwed joints, respectively. Galvanized piping or brazed joints should never be used. Ammonia accepted for pipeline transportation must meet the fokowing specifications NH, 99.5 vol % min dissolved inerts, 0.16% max, ok, 5 ppm max and water, in the form of steam condensate, 0.2% min, or distiked water, 0.5% max. 

Condensate Polishing. Ion exchange can be used to purify or poHsh returned condensate, removing corrosion products that could cause harmful deposits in boilers. Typically, the contaminants in the condensate system are particulate iron and copper. Low levels of other contaminants may enter the system through condenser and pump seal leaks or carryover of boiler water into the steam. Condensate poHshers filter out the particulates and remove soluble contaminants by ion exchange. 

Product warehouse(s) Process pipe hues—steam, condensate, water, gas, fuel oil, air, fire, instru-... 

FIG. 12-24 Spray ponds cooling curves for steam-condensing service. 

Examples of Vacuum-Related Accidents Figure 26-47 shows a jacketed tank, where the jacket was designed for low-pressure steam. When the steam was turned off and the drain valve and trap were closed, the steam condensed, causing the jacket to collapse. The jacket should have been designed for full vacuum, or a suit le vacuum relief device should have been installed on the jacket. 

Leaky valves are also a cause of erosion. Most turbine erosion-corrosion problems come from damage that takes place when the unit is not running. A shght steam leak into the turbine will let the steam condense inside the turbine, and salt from the boiler water will settle on the inside surfaces and cause pitting, even of the stainless blading. There must be two valves with a drain between them, i.e., a block valve on the header and an open drain in the line before it reaches the closed trip-throttle valve. 

Universal at 100° F) and a viscosity index of 95. They contain necessary oxidation inhibitors and antiwear agents, as the same oil is used for bearings and gear lubrication. Oils tend to retain water, either from steam condensation or from condensation that occurs in the tanks. The presence of water is detrimental as it encourages the for-... 

Environment Internal A mixture of steam, condensate, hydrogen, nitrogen, and carbon dioxide outlet temperature 165°F (75°C), inlet temperature 265°F (130°C), condensate pH 10... 

Steam condensed in a thin film along the cold tube surface. This thin film of condensate then dissolved ammonia and oxygen present in the steam, which, in combination with stress, produced the observed cracking. 

ASME, Performance Test Code on Steam Condensing Apparatus, ASME PTC 12.2 1983, American Society of Mechanical Engineers 1983. 

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