Flow sheets, auxiliary process

Flow Sheet and Mass Balances. Figure 2 represents a flow sheet of the 15,000-gallon-per-day pilot plant. The four major components are the freezer, the wash-separation column, the ice melter, and the vapor-handling device. The other essential components are the deaerator, which removes air from the saline water before it enters into the evacuated freezer the auxiliary refrigeration system, which removes heat leakage into the system and thermal inefficiencies of the process an ice scraper, pumps, controls, and instruments. 

Absorption in halogenated solvents, such as refrigerant R-12, CF2CI2, has been extensively studied at Brookhaven [S21], Harwell [T3], and Oak Ridge [M6, V4]. The process has several advantages. Fire or explosion hazards are minimal, and gas purification prior to absorption is not required. The process is flexible and does not use extremely low temperatures. Disadvantages are operation at 8 to 10 bar pressure, a fairly complex flow sheet, and the need for an auxiliary system to separate krypton from xenon and CO2. 

Auxiliary flow sheets cover the auxiliary process requirements such as steam, water, fuel, air, and other utilities. As with instrumentation, W. T. Butler, Kennecott Copper Corp., private communication, 1956,... 

Further considerations include skimmers and weir overflow rates. Skimmers should be provided on all units since even secondary effluents contain some floatable solids and grease. Overflow rates and sludge scraper design should conform to the requirements of other clarification units. The reader may refer to Chapter 9 for examples of typical flow sheets and auxiliary filtration equipment schematics, including process flow sheets for chemical feeding operations described above. 

Used to present the heat and material balance of a process. This may be in broad block form with specific key points delineated, or in more detailed form identifying essentially every flow, temperature and pressure for each basic piece of process equipment or processing step. This may and usually does include auxiliary services to the process, such as steam, water, air, fuel gas, refrigeration, circulating oil, etc. This type of sheet is not necessarily distributed to the same groups as would receive and need the piping flowsheet described next, because it may contain detailed confidential process data. 

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