Multi-Stage Steam Jet Vacuum Pumps

Since the non-condensable gases (also called inert gas, e.g. air) that leave a condenser are saturated with water vapour, it is important that every ejector stage 

As the specific volume of vapours and gases decrease with increasing pressure, the volume flow rate is reduced during the compression from 1 to 1000 mbar and the dimensions of the ejectors and condensers are also scaled down from stage to 

Surface condensers are used instead of mixing condensers, if the suction flow contains components that are not permitted to be mixed into the cooling water. A schematic representation of a four-stage steam jet vacuum pump with surface 

Frequently a combination of steam jet pumps and liquid ring pumps is installed. Here, the low suction pressure is achieved by one or several ejector stages, but 

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Figure 4.15 shows an example for a multi-stage steam jet vacuum pump with a material combination of porcelain and graphite. These materials are suitable if aggressive components are in the suction flow. 

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