摘要 |
A refining process uses a two or four stage solvent separator coupled to receive an incoming feedstream of low sulfur resid and a solvent. In the preferred two stage separator, the mixture at the top of the first separator stage is fed to the second stage separator via a heat exchanger. The mixture at the bottom of the first stage separator includes resins and asphaltenes which are fed to a hydrotreater and then, in turn, to a fractionator. The output from the bottom of this fractionator can be fed back to the resid feedstream of the first stage separator for recycled separation. The material at the top of the second stage separator is fed back through the heat exchanger where it helps heat the mixture fed from the top of the first to the second stage separator, this feedback recovers the solvent for reuse in the first stage. The material settling to the bottom of the second stage separator is fed into a catalytic cracker or processed elsewhere.
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