SIMULATION ON OPERATION OPTIMIZATION OF CYCLONE SEPARATOR IN REGENERATOR OF MTO UNIT

Abstract

Abstract: Cyclone separator is a common gas-solid two-phase separation equipment in methanol to olefins (MTO) unit, and its separation efficiency is very important for the long-term stable operation of the unit. Due to the use of a highly active catalyst in a 0.6 Mt/a MTO unit, the main air volume of the regenerator was lower than the design value, which resulted in low gas velocity at the inlet of the first-stage cyclone separator and increased loss of the fine powder catalyst under 20 μm in the unit, and catalyst consumption increased. For this purpose, the commercial computational particle fluid dynamics (CPFD) software was used to simulate the different operating conditions of the four group two-stage cyclones in the regenerator. The inlet gas velocity of the cyclone was changed by adjusting the inlet flow area and main air volume of the cyclone, and the effect of gas speed on the cyclone pressure drop and separation efficiency of the cyclone was studied. The results showed that when the main air volume was 42 241 m³/h, the gas velocity of cyclone separator could be increased by 3 m/s and the total efficiency of cyclone separator could be increased by 0.501 percentage points. Based on the simulation results, the optimal operation suggestions for cyclone separator were put forward, which could be applied to the operation adjustment of other MTO devices.

Key words: MTO, cyclone, regenerator, inlet gas velocity, separation efficiency, numerical simulation

References

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