Pure Water Tank Level Control for Multi-Point Supply Pressure

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional ultrapure water production systems face complexity in control methods when dealing with multiple use points or tanks, leading to inefficiencies and decreased water quality due to fluctuations in water usage.

Innovation Solution

A control method for pure water production systems that adjusts the flow rate and output of water supply mechanisms based on water tank levels and pressure meter readings, using flow adjustment mechanisms and inverter-controlled pumps to maintain constant water levels and pressure, allowing independent control of tank levels and supply output.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If the processing amount of the primary pure water device is varied according to usage amount, then energy efficiency is improved, but water quality of the desalinated water decreases

Engineering Contradiction:
Improveenergy efficiencyVSAvoidwater quality
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The system pre-processes and stores pure water in a storage tank before it is needed. The pure water production device produces water in advance and stores it, so that when usage increases, pre-produced water can be supplied immediately without needing to increase processing capacity at that moment. This allows the processing amount to be maintained at an optimal level for water quality while still meeting variable demand.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

A storage tank is introduced as an intermediary between the primary pure water device and the sub system. The storage tank acts as a buffer that decouples the production side from the consumption side, allowing the processing amount to be independently controlled from the supply amount. This enables maintaining optimal processing conditions for water quality while supplying water according to actual usage patterns.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If excess water is produced and stored to maintain water quality, then water quality is improved, but energy efficiency deteriorates

Engineering Contradiction:
Improvewater qualityVSAvoidenergy efficiency
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The system dynamically adjusts the supply amount from the storage tank based on actual usage patterns. The control device monitors the sub system's water consumption and adjusts the supply rate accordingly. This dynamic adjustment allows the system to produce and store water at optimal rates rather than continuously producing excess water, thereby improving energy efficiency while maintaining water quality through controlled storage and regulated supply.

Inventive Principle:
Principle #15Dynamics

3Adaptability or versatility

If the system is designed to handle multiple use points, then versatility is improved, but control complexity increases

Engineering Contradiction:
Improvemulti-use point capabilityVSAvoidcontrol complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

Multiple use points are merged into a single unified control system. The control device receives water consumption information from multiple sub systems and manages the storage tank and supply mechanisms as an integrated unit. This unified approach allows the system to handle multiple use points simultaneously while maintaining relatively simple control logic, as all points draw from the same storage buffer and are managed by a central controller rather than requiring independent control for each point.

Inventive Principle:
Principle #5Merging (Combining)

Data Source

PatentEP4678259A1Control method for pure water production system
Publication Date: 2026.01.14 KURITA WATER INDUSTRIES LTD
  • EP4678259A1 patent drawingFigure 1
  • EP4678259A1 patent drawingFigure 2
  • EP4678259A1 patent drawingFigure 3

AI summary

Once the amount of usage at each use point decreases and the measurement value of water level by water level meters 61A, 61B increases, the amount of water supply to pure water tanks 60A, 60B is reduced by reducing the opening degree of control valves 59A, 59B. This increases the water supply pressure of a pressure meter 58, and thus the output by a high pressure pump 52B is reduced through inverter control on the basis of the measurement value from the pressure meter 58. On the other hand, once the amount of usage at each use point increases and the measurement value of the water level of the pure water tanks 60A, 60B becomes smaller than this reference value, the amount of water supply to the pure water tanks 60A, 60B is increased by opening the opening degree of the control valves 59A, 59B. This reduces the water supply pressure of the pressure meter 58, and thus the output by the high pressure pump 52B is increased through inverter control such that the measurement value from the pressure meter 58 becomes substantially constant. Such a control method for a pure water production system allows for control of the amount of water supply of the entire system, particularly one having a plurality of tanks, according to the amount of water usage.