Sewage treatment device and method

The invention discloses a sewage treatment device which comprises a constant-temperature heating box, an evaporation box, a plurality of cooling fins, a steam pipeline, a condenser, a water suction pipe and a reflux pump, each cooling fin comprises an input end and an output end, the water suction pipe is connected with the input ends of the cooling fins, the output ends of the cooling fins are gathered and communicated with the reflux pump, the constant-temperature heating box heats sewage to be treated to a certain temperature, the pump body drives the water suction pipe to divide the sewageinto a plurality of cooling fins to be evaporated, evaporated gas flows into the condenser along the steam pipeline to be cooled, and unevaporated liquid flows back to the constant-temperature heating box under the action of the reflux pump. The constant-temperature heating box is adopted for heating to a certain temperature, evaporation and purification do not need to be conducted in a high-temperature and high-pressure