NOVELTY - The device comprises a vaporizer, a condensing water tank, and a drinking water machine. The vaporizer includes a straight pipe connected with a spiral tube. An inner wall of the straight pipe is arranged with a spiral groove of the spiral tube. An outer wall of the straight pipe is connected with a hollow cylindrical projection, which is connected to the spiral groove. Two ends of the spiral tube are connected with a welding tube through the hollow cylindrical projection. The hollow cylindrical projection is provided with a water inlet and a water outlet.    USE - The device is useful for providing drinking water by distilling waste heat from vehicle diesel engine (claimed).    ADVANTAGE - The device provides clean drinking water, conserves energy, and reduces exhaust heat.    DETAILED DESCRIPTION - The device comprises a vaporizer, a condensing water tank, and a drinking water machine. The vaporizer includes a straight pipe connected with a spiral tube. An inner wall of the straight pipe is arranged with a spiral groove of the spiral tube. An outer wall of the straight pipe is connected with a hollow cylindrical projection, which is connected to the spiral groove and spiral tube along a tangential direction. Two ends of the spiral tube are connected with a welding tube through the hollow cylindrical projection. The hollow cylindrical projection is provided with a water inlet and a water outlet. The condensing water tank is arranged with a water outlet interface and a snake-shaped condensing tube. A water inlet end of the snake-shaped condensing tube is connected to the water outlet. A water outlet end of the snake-shaped condensing tube is connected to the water inlet. The condensing water tank is connected to a water inlet of the vaporizer through the water outlet interface. An outlet of the vaporizer is connected to the snake-shaped condensing tube. The water outlet end of the snake-shaped condensing tube is connected with the drinking water machine. The device further comprises a control system, a sensor including accelerator pedal position feedback information, and an engine control unit for sending action signal about the position of an actuator, which is a valve of a stepper motor. The condensing water tank along transverse direction is equipped with multiple radiating fins, a carriage at the top of the tank and a spraying device. Each radiating fin is connected with the snake-shaped condensing tube and fixed firmly on the condensing water tank. The height of the water inlet end of the snake-shaped condensing tube is higher than that of the water outlet end of the snake-shaped condensing tube.