The invention discloses a technical method for purifying and reutilizing jean silkete alkali waste liquid by a
membrane method, which comprises the steps of alkali waste liquid collection, alkali waste liquid pretreatment, alkali waste liquid purification treatment, secondary use of alkali liquid reused to a
production line mangle tank after preparation and the like. The purified alkali liquid obtained by the invention has the same quality as commercial alkali. When the purified alkali liquid obtained by the invention is prepared into the concentration required by silkete threads with high-concentration
sodium hudroxide to be reused, the effect of the purified alkali liquid obtained by the invention is the same as that of the commercial alkali, so the invention has the advantages that: firstly, a large amount of
sodium hydroxide is saved, the production cost is reduced, and each silkete thread can generate the
economic benefits near million Yuan per year; secondly, the waste water quantity of high-concentration alkali liquid is reduced, so the addition of acid used for
neutralization is reduced, the load of original treatment facilities is reduced, the investment of the waste water facility in the
new production line is reduced, and the biochemical stability is enhanced; and thirdly, the production idea of clean production, recycling economy and environment protection is advocated.