References steam superheater

As the water evaporates into steam and passes on to the superheater, soHd matter can concentrate in a boHer s steam dmm, particularly on the water s surface, and cause foaming and unwanted moisture carryover from the steam dmm. It is therefore necessary either continuously or intermittently to blow down the steam dmm. Blowdown refers to the controHed removal of surface water and entrained contaminants through an internal skimmer line in the steam dmm. FHtration and coagulation of raw makeup feedwater may also be used to remove coarse suspended soHds, particularly organic matter. 

Steam produced from a boiler is referred to as dry saturated, and its temperature will correspond with the working pressure of the boiler. In some instances, particularly with shell boilers, this is perfectly acceptable. There are occasions, however, where it is desirable to increase the temperature of the steam without increasing the pressure. A superheater performs this function. Steam from the drum or shell of the boiler is passed through a bank of tubes whose external surfaces are exposed to... 

Carryover refers to the entrainment of BW (and the contaminating solids contained in the water) into the steam. Contamination of steam from entrained water may lead to deposits in superheaters, on turbine valves, and in steam traps, valves, and flash vessels. 

Steam-engine Economy.— The steam rate of an engine depends primarily on the initial pressure and superheat, back pressure and ratio of expansion. The following tables refer to perfect engines (Rankine cycle). The probable... 

This is usually referred to as the boiler or convection section of the unit. Closely spaced tubes are arranged to allow passing of the products of combustion around the tubes or through the tubes, depending on the type of unit. Most of the steam is generated in the boiler portion of the unit. In watertube units, if additional steam temperature is required by the process, the steam is then routed to a superheater. 

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