Abstract: By analyzing the current situation, advantages and disadvantages of desalting rate of "head cup water" of large flux reverse osmosis water purifier in the market, and combining the actual use situation, a new technical scheme to improve the desalting rate of "head cup water" is proposed from the user experience, so as to realize zero aging water. This scheme can effectively improve the desalting rate of "head cup water", it has a certain effect on prolonging the life of RO membrane of reverse osmosis water purifier with low cost. According to the actual use of intermittent water by users, through the application of this technology, the whole process of pure water effluent from reverse osmosis water purifier can meet the standard, the desalination rate is more than 85%.

Key words: Pure water washing film, First cup of water, TDS, Desalination rate, Large flux