Double-turbine boosting expansion machine propane dehydrogenation cold box separation system and technique

Abstract

The invention discloses a double-turbine boosting expansion machine propane dehydrogenation cold box separation system and technique. After being connected in parallel, a low-pressure expansion machine and a high-pressure expansion machine are connected with an inlet of a high-temperature separator via a third cold-mixing feeding heat exchanger. A gas outlet of the high-temperature separator is connected with an inlet of a medium-temperature separator via a second expansion heat exchanger, a liquid outlet of a high-temperature separator, a flash tank, a liquid pump and a second feeding quencher are connected sequentially, a liquid outlet of the medium-temperature separator is connected with an inlet of the flash tank, a gas outlet of the medium-temperature separator, a first expansion heat exchanger and an inlet of the high-pressure expansion machine are connected, an outlet of the high-pressure expansion machine is connected with the first expansion heat exchanger to be divided into two ways, one way is connected with a first feeding quencher via the first cold mixing feeding heat exchanger while the other way is connected with the inlet of the low-pressure expansion machine, and the outlet of the low-pressure expansion machine, the first expansion heat exchanger and the second cold-fixing feeding heat exchanger are connected. The system is reliable in equipment, high in safety, low in cost and high in recovery rate of reactor effluent.

Description

Technical field [0001] The invention relates to a propane dehydrogenation cold box separation system and a process thereof, in particular to a propane dehydrogenation cold box separation system and a process thereof. Background technique [0002] Propylene is an important petrochemical raw material. In addition to synthetic polypropylene, propylene can also be made into many downstream products such as acrylonitrile, isopropanol, phenol and acetone, acrylic acid and its lipids, and is gradually replacing traditional products such as wood and steel. , Cotton and cotton products, etc., occupy an important position in the national economy. In the long run, it will delay the extremely tight supply in the global market. [0003] The current cold box separation process is the process adopted by UOP’s Oleflex process. The low-temperature separation method is used to cool and liquefy the reactor effluent and then through the cascade expansion of the expander braked by two generators, the ...

AI Technical Summary

Problems solved by technology

This process has disadvantages such as low C3 recovery rate, risk of liquid entrainment at the inlet of the expander, difficulty in gas-liquid separation, poor equipment reliability, and large investment.

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