Pure water preparation system for wine brewing

The pure water preparation system comprises a raw water tank, a middle water tank, a pure water tank, a reverse osmosis membrane group, a filtering unit and a descaling unit, the filtering unit comprises a UF ultrafiltration device, a raw water inlet and a sewage outlet of the UF ultrafiltration device are respectively communicated with the raw water tank, and a purified water outlet of the UF ultrafiltration device is communicated with the middle water tank; the descaling unit comprises a water softener, the water inlet end of the water softener is communicated with the middle water tank, the water discharge end of the water softener is communicated with a soft water inlet of a reverse osmosis membrane group, a concentrated water outlet of the reverse osmosis membrane group is communicated with the raw water tank, and a pure water outlet of the reverse osmosis membrane group is communicated with the pure water tank; during use, water in the raw water tank flows into the UF device through the raw water inlet