Reverse Osmosis and EDI Control for Boron Removal

Solution Overview

Problem

The challenge is to produce high-purity water while reducing the cost of ultrapure water production, as increasing the current in Electric Deionized Water (EDI) devices leads to higher manufacturing costs without significant improvements in water quality.

Innovation Solution

A pure water production system comprising a reverse osmosis membrane device and an EDI device, controlled by a control device that adjusts processing conditions to maintain a boron removal rate of 99.7% or less, ensuring the treated water's boron concentration is 50 ng/L or less and specific resistance is 17 MΩ·cm or more, thereby optimizing energy efficiency and cost performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the current applied to the EDI device is increased to achieve high purity water quality, then the water quality improves, but the manufacturing cost increases

Engineering Contradiction:

Improvewater quality purityVSAvoidmanufacturing cost

Core Design Contradiction:

Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The reverse osmosis membrane device performs preliminary purification of the feed water before it enters the EDI device. This pre-treatment removes a significant portion of impurities, allowing the EDI device to operate at lower current while still achieving the required high purity water quality, thereby reducing manufacturing costs.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The water purification process is divided into two distinct stages: reverse osmosis membrane separation and electric deionization. This segmentation allows each device to perform its specialized function efficiently, with the RO device handling bulk impurity removal and the EDI device focusing on fine purification, optimizing overall system performance and cost-effectiveness.

Inventive Principle:

Principle #1Segmentation

2Manufacturing precision

If the current applied to the EDI device is increased to achieve high purity water quality, then the water quality improves, but the energy consumption increases

Engineering Contradiction:

Improvewater quality purityVSAvoidenergy consumption

Core Design Contradiction:

Manufacturing precisionVSUse of energy by moving object

Solution Approach 1:

The reverse osmosis membrane device performs preliminary purification of the feed water before it enters the EDI device. This pre-treatment removes a significant portion of impurities, allowing the EDI device to operate at lower current while still achieving the required high purity water quality, thereby reducing energy consumption.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The water purification process is divided into two distinct stages: reverse osmosis membrane separation and electric deionization. This segmentation allows each device to perform its specialized function efficiently, with the RO device handling bulk impurity removal and the EDI device focusing on fine purification, optimizing overall system performance and cost-effectiveness.

Inventive Principle:

Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enables the production of high-purity water while keeping production costs low by maintaining high energy efficiency and boron removal capability, preventing excessive power consumption and cost increases.

Implementation Method 1

a reverse osmosis membrane device (4), an electric deionized water production device (5)

Methodology Applied

Scientific EffectReverse osmosis: Reverse Osmosis

Implementation Method 2

an electric deionized water production device (5) that is disposed downstream of the reverse osmosis membrane device (4)

Methodology Applied

Scientific EffectElectrodeionization: Electrolysis

Data Source

PatentUS20230331593A1Pure water production system and pure water production method

Publication Date: 2023.10.19 ORGANO CORP

AI summary

A pure water production system includes a reverse osmosis membrane device; an electric deionized water production device that is disposed downstream of the reverse osmosis membrane device; and a control device that controls a processing condition of the reverse osmosis membrane device. The control device controls a processing condition of the reverse osmosis membrane device such that a removal rate of a specific substance of the electric deionized water production device is equal to or lower than a threshold value, and concentration of the specific substance in the treated water of the electric deionized water production device is equal to or lower than a prescribed value and specific resistance of the treated water of the electric deionized water production device is equal to or higher than a prescribed value.