Sludge drying system

The utility model relates to a sludge drying system, belongs to the technical field of waste heat recovery and overcomes the defect that direct emission of heat in high-temperature water from a rectifying column cooler causes heat waste and thermal environmental pollution. The sludge drying system mainly comprises an insulation water tank. A rectifying column cooler and a delivery pipe for excess steam are arranged on the upstream of the water tank, and a sludge drying unit and a heating unit are disposed in parallel on the downstream of the water tank. A water outflow pipe of the rectifying column cooler is connected to a water supply pipe and is communicated with the water tank through the water supply pipe. A cooling water return pipe and a heating water return pipe are connected to the downstream of the sludge drying unit and the downstream of the heating unit respectively. The cooling water return pipe and the heating water return pipe are communicated with the rectifying column cooler and the water tank