Abstract: A biohazardous liquid medical waste collection and treatment system provides on-site collection and treatment of surgical fluids. The system is mobile, and includes an upper unit and one or more lower units that are detachable from the upper unit. The upper unit includes a liquid disinfectant reservoir, liquid pump valves, and an electronic control unit which controls the operation of the pump valves. A disposable suction canister is mounted to the upper unit and collects liquid medical waste aspirated from a patient. A disposable tube set, including a motionless mixer, is connected to the disposable suction canister and the liquid disinfectant reservoir. Electronically controlled pumps (preferably peristaltic pumps) pump liquid waste from the suction canister along with the metered amount of liquid disinfectant from the liquid disinfectant reservoir through the motionless mixer and into a temporary storage receptacle on the lower unit.