Preparation equipment and process for nylon salt solution

A preparation equipment for a nylon salt solution, comprising:

• a suspension preparation device, wherein the suspension preparation device comprises a feeding unit, a continuous feeding unit, a high-shear pump, and a mixing reactor provided with a water inlet pipe, which are sequentially connected with and in communication with each other;
• the high-shear pump and the mixing reactor are cyclically connected with and in communication with each other through two connecting pipelines;
• the feeding unit is configured for feeding an aliphatic dicarboxylic acid, and the continuous feeding unit is configured for conveying the aliphatic dicarboxylic acid to the high-shear pump, such that the aliphatic dicarboxylic acid is capable of circulating with a water between the high-shear pump and the mixing reactor to form an aliphatic dicarboxylic acid suspension;
• a first salt formation reactor connected to and in communication with the suspension preparation device, wherein the first salt formation reactor comprises a first diamine feed pipe, the first salt formation reactor is configured for preparing a primary nylon salt solution by reacting the aliphatic dicarboxylic acid suspension with a diamine;
• and
• a second salt formation reactor connected to and in communication with the first salt formation reactor, wherein the second salt formation reactor comprises a second diamine feed pipe and a third diamine feed pipe, the second salt formation reactor is configured for preparing a nylon salt solution by reacting the primary nylon salt solution with the diamine;
• the second salt formation reactor further comprises a circulation pipeline of the second salt formation reactor, and the circulation pipeline of the second salt formation reactor is provided with an online near-infrared monitoring equipment, which is configured for monitoring a molar ratio of the aliphatic dicarboxylic acid to the diamine in the nylon salt solution and controlling a feed amount of the diamine in the third diamine feed pipe based on monitoring results.