Closed energy-saving and environment-friendly tank truck cleaning device and cleaning method thereof

The invention relates to a closed energy-saving and environment-friendly tank truck cleaning device which comprises a tank truck and an air bag type closing cover plate, wherein the air bag type closing cover plate is connected with a nitrogen input pipe, a cooking steam input pipe, an exhaust fan and a drying fan respectively, and is also connected with an alkali liquid washing basin, a detergent washing basin, a chemical agent washing basin, a high-pressure water washing basin, a low-pressure water washing basin, a water washing basin and a heat exchanger respectively; the heat exchanger is connected with a steam washing pipeline and an industrial water supplementation pipeline respectively; the air bag type closing cover plate is connected with a residual liquid basin, an oil-water separator, a wastewater sedimentation treatment basin, a residual acid basin and a lime reaction sedimentation basin in sequence; the wastewater sedimentation treatment basin is connected with the alkali liquid washing basin, th