Water treatment device and hot-water supply device

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional water treatment techniques fail to effectively prevent scale deposition in facilities with high-temperature water systems, leading to decreased heat exchanger performance and piping clogging, and are unstable due to pH variations from water source quality and temperature changes.

Innovation Solution

A water treatment device with a circulating water intake circuit, gas supply section for carbon dioxide microbubbles, scale isolation section, and control system that increases carbon dioxide supply during cleaning to re-dissolve accumulated scale, ensuring efficient scale removal and stable prevention of adherence in critical facility components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If carbon dioxide is supplied to a water tank to deposit scale components as carbonate compounds, then scale can be isolated and removed from the water, but scale may adhere to the wall surface of the water tank and the facility cannot be sufficiently protected from scale

Engineering Contradiction:
Improvescale removal efficiencyVSAvoidscale adherence to facility surfaces
Core Design Contradiction:
Quantity of substanceVSObject-affected harmful factors

Solution Approach 1:

The facility is divided into two distinct sections: a scale isolation section where scale components are intentionally allowed to deposit, and a scale-free section where scale deposition is prevented. This segmentation resolves the contradiction by providing a designated area for scale accumulation while protecting critical surfaces from scale adherence.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The scale isolation section is extracted as a separate functional unit from the main water storage facility. By isolating the scale deposition process to a specific section, the harmful effect of scale adherence is confined to this isolated area while the rest of the facility remains protected.

Inventive Principle:
Principle #2Taking out (Extraction)

2Reliability

If carbon dioxide is injected into water to lower pH and maintain high solubility of scale components, then scale deposition is restrained, but scale may still be deposited when pH varies due to water source quality or temperature changes

Engineering Contradiction:
Improvescale deposition restraint stabilityVSAvoidpH variation resistance
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The scale isolation section is prepared in advance as a designated area that can accommodate scale deposition. By having this pre-prepared section, the system can handle pH variations and scale deposition tendencies without affecting the overall reliability of scale restraint in the main facility.

Inventive Principle:
Principle #9Preliminary anti-action

Solution Approach 2:

The system allows pH and other water parameters to vary without causing harmful scale deposition, because any scale that does deposit is contained within the isolated section. This approach provides adaptability to parameter changes while maintaining reliable scale restraint through the isolated design.

Inventive Principle:
Principle #35Parameter changes

3Object-affected harmful factors

If scale components are deposited in the scale isolation section, then scale can be isolated from the facility, but the scale isolation section requires periodic cleaning which increases operation complexity

Engineering Contradiction:
Improvescale isolation effectivenessVSAvoidcleaning operation frequency
Core Design Contradiction:
Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The scale isolation section is designed to accumulate scale in a controlled manner, and the cleaning operation is triggered automatically when scale accumulation reaches a predetermined level. This self-service approach reduces the need for frequent manual monitoring and cleaning operations.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

Instead of continuous cleaning operations, the system employs periodic cleaning only when scale accumulation in the isolated section reaches a threshold level. This periodic action maintains scale isolation effectiveness while minimizing operation frequency and complexity.

Inventive Principle:
Principle #19Periodic action

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

The solution enables efficient removal and prevention of scale adherence in critical facility components, maintaining system performance and preventing clogging, even with varying water quality and temperature conditions.

Implementation Method 1

a gas supply section that supplies a gas containing carbon dioxide to the water flowing in the water intake circuit and lowers a pH of the water

Methodology Applied
Scientific EffectpH lowering by carbon dioxide dissolution: Absorption (physical)

Implementation Method 2

a microbubble generation device that makes a gas into microbubbles

Methodology Applied
Scientific EffectMicrobubble generation: Bubble

Implementation Method 3

a scale reaction section for making the water flowing in the water intake circuit and the gas react with each other to deposit scale in the water

Methodology Applied
Scientific EffectScale deposition by chemical reaction: Precipitation

Implementation Method 4

a scale isolation section that is provided on a downstream side of the gas supply section in a direction of the flow of the water in the water intake circuit and isolates scale deposited in the water flowing in the water intake circuit

Methodology Applied
Scientific EffectScale isolation by sedimentation: Sedimentation

Implementation Method 5

the gas supply section supplies the gas containing carbon dioxide to water flowing into the scale isolation section so as to re-dissolve the scale accumulated in the scale isolation section

Methodology Applied
Scientific EffectScale re-dissolution by carbon dioxide: Absorption (physical)

Data Source

PatentEP3056473B1Water treatment device and hot-water supply device
Publication Date: 2020.03.11 MITSUBISHI ELECTRIC CORP
  • EP3056473B1 patent drawingFigure 1~2
  • EP3056473B1 patent drawingFigure 3(a)~3(b)
  • EP3056473B1 patent drawingFigure 4(a)~4(c)

AI summary

A water treatment device that efficiently removes scale components in water at a part that is different from a facility to be protected from scale and enables stable restraint of adherence of scale to the facility is provided. A water treatment device 10 installed in the hot-water supply device 1 includes, e.g., a water intake piping 11, a water intake pump 12, a gas supply section 13, a scale reaction section 15, a scale isolation section 16, a channel changeover valve 17 and a water discharge piping 18. In descaling treatment, while water is circulated from the hot-water storage tank 2 to the water intake piping 11, a gas containing carbon dioxide is supplied from the gas supply section 13 to the water. Consequently, scale components in the water react with the carbon dioxide in the water in, e.g., the scale reaction section 15 and scale is thereby deposited, and the scale is removed by the scale isolation section 16. Consequently, scale adherence and accumulation in a part that is necessary for maintenance of a function of the hot-water supply device 1, that is, a part to be protected from scale can be restrained.