Apparatus and process for preparing polyamide

1 . An apparatus ( 100 ) for preparing a polyamide, which comprises a reactor ( 10 ) provided with a stirrer ( 20 ) in which polycondensation of a diamine and a dicarboxylic acid is carried out; and a buffer ( 30 ), a fractionation distillation column ( 50 ), and a condenser ( 70 ) sequentially installed above the reactor ( 10 ), wherein the buffer ( 30 ) has an inner diameter larger than that of a pipe connection unit ( 16 ) by 10% or more and a ratio of length to inner diameter (L/D) of 1 or more, and the content of the diamine in the condensation water discharged through the condenser is 1% by mole or less.

2 . The apparatus ( 100 ) for preparing a polyamide of claim 1 , wherein the reactor ( 10 ) further comprises a heating device capable of heating the reaction mixture inside the reactor to a temperature of 150 to 300° C.

3 . The apparatus ( 100 ) for preparing a polyamide of claim 1 , wherein the buffer ( 30 ) has an inner diameter larger than that of the pipe connection unit ( 16 ) by 20% or more and a ratio of length to inner diameter (L/D) of 2 to 10.

4 . The apparatus ( 100 ) for preparing a polyamide of claim 2 , wherein the buffer ( 30 ) is neither heated nor cooled separately.

5 . The apparatus ( 100 ) for preparing a polyamide of claim 1 , wherein the fractional distillation column ( 50 ) has a number of plates, or theoretical plates, of 5 to 30.

6 . The apparatus ( 100 ) for preparing a polyamide of claim 5 , wherein the fractional distillation column ( 50 ) has an operating temperature of 100 to 150° C.

7 . The apparatus ( 100 ) for preparing a polyamide of claim 5 , wherein the condenser ( 70 ) has an operating temperature of 0 to 20° C.