Rotating Pressure Exchange Device Segmentation for Compact Desalination

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Solution Overview

Problem

Existing pressure exchange devices in seawater desalination facilities face challenges such as increased size and weight, leading to higher material and manufacturing costs, as well as reduced efficiency due to increased torque requirements for larger rotors, which complicates installation and management of multiple devices.

Innovation Solution

A pressure exchange device design featuring a rotator with first and second flow paths arranged around a rotation axis, where the flow paths are connected via communication sections on lateral members, allowing for reduced axial length and cost-effective downsizing without compromising treatment flow rate, and incorporating a retentive member to maintain pressure balance and reduce abrasion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the number of pressure transmission units is increased or the cross-sectional area of each unit is expanded to increase treatment flow rate, then the treatment flow rate is improved, but the rotor size and weight increase, leading to higher material costs and manufacturing costs

Engineering Contradiction:
Improvetreatment flow rateVSAvoidrotor weight
Core Design Contradiction:
ProductivityVSWeight of moving object

Solution Approach 1:

The rotor is divided into multiple independent pressure transmission units arranged around the rotation axis. Each unit contains separate flow paths for first and second fluids, allowing the treatment flow rate to be increased by adding more units rather than enlarging individual units, thus avoiding proportional increases in rotor weight and material costs.

Inventive Principle:
Principle #1Segmentation

2Productivity

If the rotor size is increased to increase treatment flow rate, then the treatment flow rate is improved, but the torque required to rotate the rotor increases, reducing efficiency

Engineering Contradiction:
Improvetreatment flow rateVSAvoidenergy for rotation
Core Design Contradiction:
ProductivityVSUse of energy by moving object

Solution Approach 1:

By segmenting the pressure transmission function into multiple independent units distributed around the rotor, the system can process larger flow rates without requiring a single large rotor. This segmentation allows each unit to be rotated with relatively low torque, and the combined effect of multiple units achieves the desired total flow rate, thereby improving energy efficiency.

Inventive Principle:
Principle #1Segmentation

3Strength

If expensive materials such as ceramics are used for the rotor to achieve high rigidity and abrasion resistance, then the mechanical properties are improved, but material costs and manufacturing costs increase

Engineering Contradiction:
Improverigidity and abrasion resistanceVSAvoidmanufacturing cost
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

The rotor is designed as a segmented structure with multiple pressure transmission units that can be manufactured separately and then assembled. This segmentation allows for the use of more cost-effective materials and manufacturing processes for each individual unit, while the overall assembled rotor achieves the required rigidity and abrasion resistance through its structural design rather than relying solely on expensive materials.

Inventive Principle:
Principle #1Segmentation

4Length of moving object

If the axial length of the rotator is reduced for downsizing, then the device size and cost are reduced, but the treatment flow rate may be compromised

Engineering Contradiction:
Improveaxial lengthVSAvoidtreatment flow rate
Core Design Contradiction:
Length of moving objectVSProductivity

Solution Approach 1:

Instead of increasing the axial length to accommodate more pressure transmission units, the invention arranges multiple units radially around the rotation axis in the circumferential direction. This dimensional change from axial to radial arrangement allows the treatment flow rate to be increased without extending the axial length, achieving downsizing while maintaining productivity.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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 design achieves downsizing and cost reduction while maintaining treatment flow rate, improving workability and reducing energy requirements for rotation, and enhances durability without using expensive materials.

Implementation Method 1

a pressure exchange device that exchanges pressure between a first fluid and a second fluid

Methodology Applied
Scientific EffectPressure exchange: Hydraulic Press

Implementation Method 2

a communication section configured to communicate with the first flow path and the second flow path, and exchange pressure between the first fluid and the second fluid

Methodology Applied
Scientific EffectFluid communication: Hydraulic Press

Data Source

PatentEP2762730B1Pressure exchange device
Publication Date: 2019.08.07 KUBOTA CORP
  • EP2762730B1 patent drawingFigure 1
  • EP2762730B1 patent drawingFigure 2
  • EP2762730B1 patent drawingFigure 3A~3C

AI summary

Provided is an efficient pressure exchange device which can be made more compact and for which the cost can be reduced, without reducing the processing flow rate. This pressure exchange device is equipped with a rotator (40), for which first flow paths (41) through which a first fluid flows in and out and second flow paths (42) through which a second fluid flows in and out are arranged around a shaft center so as to penetrate through in the direction of the rotation axis; a first lateral member (20), for which a first fluid inflow path (21) that guides the first fluid into the first flow paths, a second fluid outflow path (22) that guides the second fluid, in which pressure has been exchanged for the pressure of the first fluid, from the second flow paths, a second fluid inflow path (23) that guides the second fluid into the second flow path, and a first fluid outflow path (24) that guides the first fluid, in which pressure has been exchanged for the pressure of the second fluid, from the first flow paths, are formed in the thickness direction; and a second lateral member (30), for which communication sections (31, 33) that connect the first flow paths and the second flow paths and exchange pressure between the first fluid and the second fluid are formed. The rotator is rotatably sandwiched between the first lateral member and the second lateral member.