Steam purge

Shutting off purge steam without pressuring with uoucoudeus-able vapors... 

K-HTC is used more successfully for sorption-enhanced water-gas shift [27]. Breakthrough of CO occurs at the same time as breakthrough of CO2 [37] and the amount of steam necessary for desorption can be kept relatively low [27]. A commercial high-temperature shift catalyst can be used. During desorption in steam, the catalyst can be oxidized, so it is necessary to add some hydrogen to the purge steam [27]. 

J.2 Minimize Use of Aeration and Purge Steam. Excess fines will be generated by overuse of aeration and steam purges during cracker operation. 

One way to combat this problem is with steam. As soon as the flow is interrupted, high-pressure purge steam is automatically opened into the heater tube inlets. The steam blows the residual liquid out of the tubes, and also helps remove heat from the tubes. 

The correct way to prevent this sort of firebox explosion is to use firebox purge steam. A typical heater firebox might have a half dozen 3-in purge steam connections. The idea is to displace the air in the firebox with steam. Then, the flows of combustible process liquid and fuel gas may be safely stopped, without fear of entering the explosive region. This purge steam is different from the purge steam used in the heater s tubes. 

Design techniques for gas-phase adsorption range from empirical to theoretical. Methods have been developed for equilibrium, for mass transfer, and for combined dynamic performance. Approaches are available for the regeneration methods of heating, purging, steaming, and pressure swing. Several broad reviews have been published on analytical equations... 

The effectiveness of steam purging depends on heat loss from the stack. Thus, weather conditions are a factor. With purge steam in the flare stack, isothermal conditions exist from the bottom flange of the stack upward to an elevation determined by the weather and purge rate. Above this elevation, the stack wall temperature decreases with height. 

Tower trays were repeatedly upset due to pressure surges resultii from water accumulating in the tower during short unit outages. The source of water was condensation of purge steam used under the cohmm relief valves to prevent their inlets from plugging. 

Purge steam is sometimes called snuffing or box steam. 1 have a few rules about the design and operation of this system to ensure its safe use ... 

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