Vapor degreasing process

Appropriate characteristics for solvents to be used in the vapor degreasing process are as follows ... 

Figure 14.8.17. Closed-loop batch vapor degreasing process.

Chlorinated hydrocarbons such as trichloroethylene and perchloroethyl-ene are the solvents most commonly used for vapor degreasing, particularly the former. Considerable detail on the equipment required and the vapor degreasing process is given in Ref. ... 

Use as solvent in vapor degreasing. Process enclosure local exhaust ventilation chilling coils substitution. 

The vapor degreasing process includes two of the three simple steps noted in Chapter 1.2, which collectively (or individually) may be repeated as often as necessary ... 

Figure 1.18 Single-Sump Vapor Degreasing Process...

Solvent cleaning is valued for at least three characteristics, including the capability to (1) completely remove a soil from a surface by taking it into solution, (2) rinse a wetted surface with pristine fluid, and (3) dry a wetted surface hy rapid evaporation of the fluid wetting it. Item 2 is what s meant by the phrase "vapor degreasing." Item 3 is normally provided in any vapor degreasing process. 

In the early 1990s, the Class II B cosolvent process was relatively popular for other applications. Marketed as the AVD (Advanced Vapor Degreasing) process, the SA was a mixture of aliphatic hydrocarbons supplemented by an ester of dibasic acids (Ref. 3, Chapter 19). The RA was either PFC-5060 (perfluorinated hexane), or later HFC-43-10mee. Figure 3.15 is an image of an operating AVD vapor degreaser. 

The distillation column associated with a Class IV cosolvent process is not that found within a conventional singlesolvent vapor degreasing process. 

That in the single-solvent vapor degreasing process only operates when needed (batch mode), and produces... 

These materials have a wide range of boiling points, from a low of 39°C for methylene chloride to a high of 121°C for perchloroethylene. Trichloroethylene and perchloroethylene are the solvents most commonly used for vapor degreasing, particularly the former. Considerable detail on the equipment required and the vapor degreasing process is given in Ref. [3]. The discussion of chlorinated solvents is of historical and technical interest because the use of nearly every one of them has been banned. The health, safety, and environmental risks of this class of materials are far too high to justify their use in spite of the excellent results that their application can yield. 

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