Patent ID: 6579445
Filing Date: 2003-06-17
Classification: C02F,Y10S

Abstract:
A system for the production of ultrapure water having a specific resistance of at least 18.0 megohm.cm and a total organic carbon content of less than one ppb comprising the following elements all in fluid communication with each other:(a) a source of feed water; (b) a pump; (c) at least two dual housings A and B containing at least five water purification media, wherein each dual housing has two juxtaposed chambers 1 and 2 separated by a common wall and in series fluid communication with each other; (d) an ultraviolet reactor chamber between two of said at least two dual housings; (e) a specific resistance sensor; (f) an ultrafilter having a rating of 30,000 Dalton molecular weight cutoff situated between said at least two dual housings and said specific resistance sensor; (g) a first flush valve between said at least two dual housings and said ultrafilter and a second flush valve and a second check valve between said ultrafilter and said pump; (h) a dispense valve capable of delivering ultrapure water from the system and preventing upstream flow when dispensing; (i) a point-of-use filter downstream and proximate to said dispense valve and having an average pore size rating of up to 0.2 micron and capable of removing particles and bacteria; (j) a first check valve between said pump and said dispense valve to prevent backflow of feed water; and (k) a sampling port with filter attachment in communication with an instrument capable of analyzing total organic carbon content of the ultrapure water produced by the system wherein dual housing A contains the following media in the following order in chambers 1 and 2:chamber 1redox media acid-washed coconut shell activated carbon chamber 2semiconductor grade mixed bed resin and dual housing B contains the following media in the following order in chambers 1 and 2:chamber 1catalytic activated carbon having a peroxide number of &lE;14 acid-washed coconut shell activated carbon semiconductor grade mixed bed resin chamber 2acid-washed coconut shell activated carbon semiconductor grade mixed bed resin.