摘要 |
In the recovery of natural gas liquids by partial condensation, flashing, and compression, minimum and maximum temperature control of partially condensed feed stream hydrocarbons to a product separator is imposed by a minimum temperature control system which provides the same set point to the pressure controllers on the compressor suction scrubbers for both the product and the flashed vapor produced from the liquid outlet of the product separator with one of the two output signals responsive to the pressure of the product suction scrubber or the flashed vapor suction scrubber manipulating, by way of a selective relay, the engine speed controller of the dual compressor unit taking suction from the two scrubbers; and a maximum temperature controller which controls the rate of by-pass of natural gas feed around the partial condensation-separation system unless, by means of a selective relay, compressor availability is a more limiting criterion.
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