Hopper Dredger Filter Overflow Captures Fine Particles

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Trailing suction hopper dredgers face reduced load capacity when dredging fine particles due to slow settling, leading to increased environmental impact from suspended particles in the overflow plume.

Innovation Solution

An overflow system with a filtering device comprising pleated mesh layers and rinsing nozzles, which captures and recirculates suspended particles back to the hopper, reducing turbidity and environmental impact.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If an overflow system is used to drain head water, then load capacity is improved, but suspended particles in the overflow create environmental harm through plume formation

Engineering Contradiction:
Improveload capacityVSAvoidplume formation
Core Design Contradiction:
Quantity of substanceVSObject-generated harmful factors

Solution Approach 1:

A filtering device is introduced as an intermediary between the overflow system and the environment. The filter captures suspended particles from the overflow water before discharge, preventing plume formation while maintaining the load capacity benefits of the overflow system

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The filtering device converts the harmful suspended particles in the overflow into a beneficial resource by collecting them for potential reuse or proper disposal, transforming the environmental problem into a solution

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

2Object-affected harmful factors

If overflow systems are not used when dredging fine particles, then environmental impact is reduced, but load capacity decreases

Engineering Contradiction:
Improveenvironmental impactVSAvoidload capacity
Core Design Contradiction:
Object-affected harmful factorsVSQuantity of substance

Solution Approach 1:

The filtering device serves as a mediator that enables the use of overflow systems for fine particle dredging by capturing suspended particles before discharge, thus allowing load capacity improvement without increasing environmental impact

Inventive Principle:
Principle #24Intermediary (Mediator)

3Object-affected harmful factors

If a filtering device is added to the overflow system, then environmental impact is reduced by capturing suspended particles, but device complexity increases

Engineering Contradiction:
Improveenvironmental impactVSAvoidsystem complexity
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The filtering device utilizes porous filtering materials that passively capture suspended particles through physical filtration. This approach reduces system complexity by relying on the inherent properties of porous materials rather than complex active filtration mechanisms

Inventive Principle:
Principle #31Porous materials

Solution Approach 2:

The filtering device is designed to operate passively using the natural flow of overflow water, requiring minimal external energy input or complex control systems. The system serves itself by utilizing the existing hydraulic conditions to drive the filtration process

Inventive Principle:
Principle #25Self-service

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

Enhances load capacity by filtering fine particles and reduces environmental impact by minimizing the plume generated during dredging operations, allowing for efficient handling of fine materials.

Implementation Method 1

a filtering device and wherein said fractions outlet is coupled with said filtering device downstream from at least one filtering layer

Methodology Applied
Scientific EffectFiltration: Filter (physical)

Implementation Method 2

the means for rinsing the fractions from the filtering device comprises at least one nozzle. Optionally, the at least one nozzle can rinse the fractions with a pulsating spray

Methodology Applied
Scientific EffectFluid spray: Fluid Spray

Implementation Method 3

the filtering device comprises means for vibrating at least one mesh layer

Methodology Applied
Scientific EffectMechanical vibration: Vibration

Implementation Method 4

The mixture is reduced in speed when in the dredger hopper, and this speed reduction allows for the settling of components suspended in the mixture

Methodology Applied
Scientific EffectGravitational settling: Settling

Data Source

PatentEP3154658B1Hopper dredger with filter overflow device
Publication Date: 2020.03.18 IHC HOLLAND IE BV
  • EP3154658B1 patent drawingFigure 1
  • EP3154658B1 patent drawingFigure 2a
  • EP3154658B1 patent drawingFigure 2b

AI summary

An overflow system includes an inlet for taking in head water; a filtering device, fluidly coupled with the inlet, for separating suspended fractions from the head water; a fractions outlet coupled with the filtering device for transport of the fractions away from the overflow system; and a fluid outlet for draining water from the overflow system.