Apparatus for preparing oligomer

An apparatus for preparing oligomer, comprising:

• a reactor receiving a monomer stream and a solvent stream, allowing an oligomerization reaction to proceed, and discharging a gaseous first discharge stream and a liquid second discharge stream;
• a gas-liquid separator separating the gaseous first discharge stream of the reactor into a liquid phase and a gas phase and feeding a liquid bottom discharge stream to the reactor;
• a first transfer line extending from a bottom of the gas-liquid separator to a region spaced apart from an inner wall of the reactor at a position higher than a reaction region inside the reactor and transferring the liquid bottom discharge stream of the gas-liquid separator;
• a solvent transfer line transferring the solvent stream to the reactor;
• a second transfer line separated from the solvent transfer line and transferring a part of the solvent stream to a region spaced apart from the inner wall of the reactor at a position higher than a height at which the first transfer line inside the reactor is formed;
• a first spray nozzle unit connected to an end of the first transfer line inside the reactor and having n spray nozzles formed to be spaced apart from each other, wherein n is an integer of 2 or more;
• and
• a second spray nozzle unit connected to an end of the second transfer line inside the reactor and having n−1 spray nozzles formed to be spaced apart from each other,
• wherein a spray angle of the liquid bottom discharge stream of the gas-liquid separator sprayed from the spray nozzles formed in the first spray nozzle unit is 30° to 90°, and
• wherein a spray angle of the solvent stream sprayed from the spray nozzles formed in the second spray nozzle unit is 91° to 120°.