Efficient blowdown system for mine underground car washing chamber

The invention discloses an efficient blowdown system for an underground car washing chamber of a mine. The efficient blowdown system comprises a sewage collection system, a sewage precipitation system and a sewage discharge system, the sewage collection system is used for collecting sewage on the ground of the car washing chamber and discharging the sewage into the sewage precipitation system; the sewage precipitation system is used for precipitating sewage; the sewage discharge system is used for discharging part of sewage in the sewage precipitation system; the sewage collection system comprises three drainage ditches which are arranged in an H shape and are respectively a first-stage horizontal drainage ditch, a second-stage vertical drainage ditch and a third-stage horizontal drainage ditch; water in the first-stage horizontal drainage ditch is converged to the second-stage vertical drainage ditch, water in the second-stage vertical drainage ditch is converged to the third-stage horizontal drainage ditch,