Dry and wet dual-purpose closed countercurrent cooling tower

The utility model relates to the technical field of cooling towers, in particular to a wet and dry closed countercurrent cooling tower which comprises a tower body and a control cabinet, a water collecting tank is arranged at the bottom of the tower body, a water filling nozzle and a water tank outlet are formed in the water collecting tank, a variable-frequency booster pump is connected to the water tank outlet, and an air inlet is formed in the side wall of the tower body and located in the lower portion of the tower body. An air inlet is formed in the tower body, a grating plate is connected to the air inlet, an air outlet is formed in the top of the tower body, a fan is connected to the top of the tower body, a water collector, a spraying assembly and a heat exchange coil pipe are sequentially arranged in the tower body from top to bottom, the spraying assembly comprises a spraying water pipe and a nozzle, the spraying water pipe is connected with a variable-frequency booster pump through a pipeline, and