Sewage Sludge Dewatering via Ultrafine Bubbles and Acoustic Energy

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Solution Overview

Problem

Conventional dewatering systems for sewage sludge face challenges in achieving high throughput and energy efficiency, particularly when scaled down for smaller industrial sites, resulting in insufficient dewatering rates and increased energy consumption.

Innovation Solution

A method involving the application of ultrafine bubbles, acoustic energy, and an electric field to facilitate the separation and transport of water molecules from solid matter, utilizing an ultrafine bubble generator, ultrasound generator, and electrokinetic reactor to enhance dewatering efficiency and reduce energy input.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional dewatering systems are scaled down for smaller industrial sites, then adaptability is improved, but energy efficiency deteriorates with increased energy consumption per tonne

Engineering Contradiction:
Improveadaptability to smaller industrial sitesVSAvoidenergy consumption per tonne
Core Design Contradiction:
Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The patent combines three dewatering mechanisms (ultrafine bubble aeration, acoustic energy, and electrokinetic processes) into a single integrated apparatus. The bubble generator, ultrasound generator, and electrokinetic reactor work synergistically to achieve high dewatering rates while maintaining energy efficiency in scaled-down systems, resolving the contradiction between adaptability and energy consumption.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The invention uses a composite approach by integrating multiple physical fields (gas bubbles, acoustic waves, and electric fields) within one system. This composite methodology enables the apparatus to function effectively at smaller scales without the energy penalties typically associated with downscaled conventional systems.

Inventive Principle:
Principle #40Composite materials

2Ease of operation

If conventional EK systems are used for dewatering, then ease of operation is improved, but productivity deteriorates with insufficient dewatering rates

Engineering Contradiction:
Improveease of operationVSAvoiddewatering rate
Core Design Contradiction:
Ease of operationVSProductivity

Solution Approach 1:

The patent merges electrokinetic processes with ultrafine bubble aeration and acoustic energy application. This combination enhances the dewatering rate by creating cavitation effects and improving water-solids separation efficiency, thereby increasing productivity while maintaining operational simplicity through automated control.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The invention introduces ultrafine bubbles with specific size parameters (average diameter of up to 10μm) and applies acoustic energy at optimized levels to enhance electrophoretic mobility. These parameter changes significantly improve the dewatering rate compared to conventional EK systems, resolving the productivity limitation.

Inventive Principle:
Principle #35Parameter changes

3Productivity

If large scale dewatering systems are used, then productivity is improved with high throughput, but device complexity increases

Engineering Contradiction:
ImprovethroughputVSAvoiddevice complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent segments the dewatering process into three distinct functional modules: bubble generation, acoustic energy application, and electrokinetic reaction. This segmentation allows the system to achieve high throughput while maintaining manageable complexity through modular design, where each component performs a specific function and can be independently optimized.

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

The method achieves high dewatering rates at low energy input by creating cavitation effects and electrophoretic mobility, effectively separating water from solid matter, and is scalable for various industrial applications.

Implementation Method 1

applying a plurality of ultrafine bubbles to a sludge to form an at least partially aerated sludge

Methodology Applied
Scientific EffectAeration: Aeration

Implementation Method 2

the applied acoustic energy to agitate the ultrafine bubbles produces a cavitation effect on the bubbles

Methodology Applied
Scientific EffectCavitation: Cavitation

Implementation Method 3

applying acoustic energy to the aerated sludge to agitate at least a portion of the ultrafine bubbles

Methodology Applied
Scientific EffectAcoustic energy: Acoustic Radiation Pressure

Implementation Method 4

applying an electric field to the aerated sludge to impart an electrophoretic mobility to the ultrafine bubbles to thereby facilitate separation and transport of water molecules from solid matter within the sludge

Methodology Applied
Scientific EffectElectrophoresis: Electrophoresis

Implementation Method 5

applying an electric field to the aerated sludge

Methodology Applied
Scientific EffectElectric field: Electric Field

Data Source

PatentEP3765411B1An improved dewatering method and apparatus
Publication Date: 2023.06.07 NATURAL SYNERGIES LTD
  • EP3765411B1 patent drawingFigure 1
  • EP3765411B1 patent drawingFigure 2a~2b
  • EP3765411B1 patent drawingFigure 3~4

AI summary

The present invention provides a method and an apparatus for treating sewage sludge, the method comprising applying a plurality of ultrafine bubbles to a sludge to form an at least partially aerated sludge, applying acoustic energy to the aerated sludge to agitate at least a portion of the ultrafine bubbles and applying an electric field to the aerated sludge to impart an electrophoretic mobility to the ultrafine bubbles to thereby facilitate separation and transport of water molecules from solid matter within the sludge.