Retrofit of Vacuum Systems in Process Industries

Chemical Process Retrofitting and Revamping Techniques and Applications, First Edition. Edited by Gade Pandu Rangaiah. 

This section reviews various vacuum-generation methods applicable to process industries. There are many types of equipment that can be used for vacuum generation in industries. 

Dry Vacuum Pumps (DVPs) These use the operating principles of rotary-lobe roots blowers, claw compressors or screw compressors, and hence require electrical power. They run dry and hence at very high temperature due to the heat of compression. Usually, 

The annual cost of operating a vacuum system is several times the equipment cost. So, a detailed review of the operating cost of a vacuum system is essential. For example, use of chilled water instead of cooling water can reduce steam/power consumption of the vacuum system. It also eliminates cavitation problems associated with LRVPs used at low suction pressures. Although chilled water is costlier than cooling water, it can be attractive if the electricity price is low or waste heat is available for chilled water production. Selection of SJE, LRVP, DVP, SJE-LRVP or SJE-DVP combination depends on many factors listed in Table 11.1. 

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