A system is configured for continuous polyamide synthesis. The system includes a vent condenser and a vacuum pump. The vent condenser is coupled to a polymerization finisher. The vent condenser has a liquid reservoir and a vent discharge port above a level of the liquid reservoir. The vacuum pump is coupled to the vent discharge port by an intake line. The vacuum pump has an output port and a rotary shaft. A gaseous mixture proximate the vent discharge port is removed at a rate determined by a speed of the rotary shaft. The vacuum pump is configured to have a liquid ring seal.