| dc.description.abstract | Impeller exchange, speed increase, and supercharging are the
usual means to increase the capacity of existing industrial turbocompressors
of the single shaft type. Replacing an existing rotor by
a new one with wider impellers normally requires wider stationary
flow channels as well and, therefore, necessitates some additional
space that must be available within the compressor casing. Speed
increase requires, besides the aerodynamics, careful consideration
of rotordynamics and checking of mechanical components.
Suction side boosting, on the other hand, leaves the existing
compressor "almost" untouched since the booster forms a separate
unit. One case study of a turbine driven hydrocarbon compressor
in a fluid catalytic cracking (FCC) plant built in 1968, illustrates
the complete exchange of the aero-package in combination with
speed increase in two large steps to increase the volume flow from
100 percent to a spectacular value of 243 percent. The uprates
included retrofitting bearings and shaft seals. In another example,
a turbine driven air compressor in a terephthalic acid (PTA) plant
built in 1980 is described, which was uprated to 164 percent of its
original capacity by boosting. | en |
