The invention discloses a
softening treatment method for high-
hardness water, which comprises a pretreatment unit and a salt separation unit, and comprises the following steps: 1) introducing the high-
hardness water into the pretreatment unit, and removing
turbidity and
silicon in the high-
hardness water in the pretreatment unit to ensure that the
turbidity of the
effluent is less than or equal to 20NTU and the
silicon (based on SiO2) is less than or equal to 20mg / L; (2) cooling the pretreated
effluent, feeding the cooled
effluent into a salt separation unit for salt separation, mainly retaining
calcium and
magnesium ions on a concentrated water side, and mainly feeding
ammonia nitrogen into a
produced water side; concentrated water enters a
sewage treatment
plant or is further softened, and
produced water is conveyed to a backwater
system. The method preferably comprises a recycling unit, so that
resource utilization is realized. According to the method, the removal effect that the total hardness of high-hardness water with the hardness larger than 500 mg / L is reduced by 50-98% can be achieved; and especially when being used for
coal gasification ash
water softening treatment, the
softening agent has beneficial hardness removal effect, simultaneously removes
silicate scales, effectively solves the problem of scaling of a gasification furnace
system, and prolongs the stable operation period.