Method and apparatus for supplying water of specified concentration
AssigneeKurita Water Industries Ltd.
InventorHideaki Iino
Life of this patent
Estimating the term…
Abstract
Provided are a method for supplying water of specified concentration, including: a step of adding at least two liquids, a conductive first liquid and a non-conductive second liquid, to ultrapure water to produce water of specified concentration containing a first liquid-component and a second liquid-component at specified concentrations, in which a mixed solution in which the first liquid and the second liquid are mixed at a specified mixing ratio in advance is prepared; and the mixed solution is added to the ultrapure water so that a conductivity or specific resistance of the ultrapure water after the addition satisfies a specified value, and an apparatus therefor.
Claims4
A method for supplying water of specified concentration, comprising:
- supplying a conductive first liquid-component to a reservoir while measuring an amount thereof;
- supplying a non-conductive second liquid-component to the reservoir while measuring an amount thereof, to thereby produce in the reservoir a mixed solution with a specified concentration containing the first liquid-component and the second liquid-component;
- adding the mixed solution in the reservoir to ultrapure water flowing through a line;
- measuring a conductivity or specific resistance of the ultrapure water in the line into which the mixed solution has been added;
- measuring an instantaneous flow rate of the ultrapure water in the line into which the mixed solution has been added;
- and
- controlling an amount of the mixed solution in the reservoir added to the line so that a value of the conductivity or the specific resistance is a specified value.
An apparatus for supplying water of specified concentration, comprising:
- a reservoir;
- a conductive first liquid line providing a predetermined amount of a conductive first liquid to the reservoir;
- a conductive second liquid line providing a predetermined amount of a non-conductive second liquid to the reservoir, to thereby prepare in the reservoir a mixed solution of the conductive first liquid and the non-conductive second liquid at a specified mixing ratio;
- a mixed solution feeder configured to supply the mixed solution in the reservoir into ultrapure water;
- a conductivity meter or a resistivity meter configured to measure a conductivity or specific resistance of the ultrapure water into which the mixed solution has been supplied;
- an instantaneous flow meter configured to measure an instantaneous flow rate of the ultrapure water into which the mixed solution has been supplied;
- and
- a controller configured to control the mixed solution feeder so that a value detected by the conductivity meter or the resistivity meter is a specified value.
Dependencies are inferred from the claim text.