The present invention provides a method and
system for zero-emission treatment of
wastewater. The
wastewater includes
coking wastewater, cold rolling
wastewater, power
plant desulfurization wastewater, and
sintering acid-making wastewater. The treatment method includes: performing first concentration pretreatment on the
coking wastewater; performing second concentration pretreatment on the cold rolling wastewater; performing concentrated wastewater pretreatment on the power
plant desulfurization wastewater,
sintering acid-making wastewater, first concentrated water, and second concentrated water; performing membrane separation and concentration treatment on the first
produced water; performing first
crystallization treatment on the second
produced water; and performing second
crystallization treatment on the third concentrated water. The zero-emission treatment method for wastewater provided by the present invention, through the first concentration pretreatment of the
coking wastewater and the second concentration pretreatment of the cold rolling wastewater, and then mixing the first concentrated water, second concentrated water, power
plant desulfurization wastewater, and
sintering acid-making wastewater for concentrated wastewater pretreatment, membrane separation and concentration treatment, first
crystallization treatment, and second crystallization treatment, realizes the co-production of salt and
nitrate by extracting salt from the wastewater, and reuses the obtained industrial
fresh water to achieve zero-emission of wastewater.