Multi-phase combination reaction system and reaction method

A reaction method carried out in a system comprising a fixed bed hydrogenation reactor, wherein the fixed bed hydrogenation reactor comprises, arranged from top to bottom, a first hydrogenation reaction area, a gas-liquid separation area, a second hydrogenation reaction area and a third hydrogenation reaction area disposed in one reaction vessel, the gas-liquid separation area is provided with a inlet for a feedstock oil, a hydrogen inlet is provided between the second hydrogenation reaction area and the third hydrogenation reaction area the method comprises:

• S1:
• subjecting the feedstock oil to a gas-liquid separation in the gas-liquid separation area to obtain a gas phase A and a liquid phase A;
• S2:
• introducing a hydrogen gas through the hydrogen inlet arranged between the second hydrogenation reaction area and the third hydrogenation reaction area, subjecting the hydrogen gas and the liquid phase A to a gas-liquid reaction countercurrently in the second hydrogenation reaction area to obtain a material B,
• wherein the material B contains hydrogen dissolved therein;
• subjecting unreacted hydrogen gas and the gas phase A to a first hydrogenation reaction in the first hydrogenation reaction area to obtain a material C;
• and
• S3:
• the material B downwardly entering the third hydrogenation area for carrying out a third hydrogenation reaction to obtain a material D.