Home / What’s hiding in your harbour floor

What’s hiding in your harbour floor

Smarter sediment handling can lower costs, reduce pollution, and turn harbour waste into a resource

Making marine sediment cleaner with hydrocyclones and hands on testing, IPU is working with municipalities, contractors and environmental authorities to manage dredged sediment in a smarter, less polluting and more cost efficient way.

Why this matters

Smarter handling of dredged sediment is about avoiding, making fish and mussels poisonous to humans and it’s about improving infrastructure maintenance, reducing cost and turning waste into resource. That’s what this work aims to support.

A typical day on the job for a IPU colleague, finding smart solutions to complex problems.

Hands-on sediment sampling by IPU engineers in Aarhus harbour

At IPU, we like to get our hands dirty

Especially when the goal is to turn complex technical problems into practical solutions.

Right now, we’re diving into the seabed in Vejle and Aarhus determining which parts of harbour sediment are contaminated and which parts could be safely reused.

Harbours across Denmark contain old sediment layers. Some include heavy metals or organic pollution, while others are relatively clean. But treating everything as hazardous waste is both costly, inefficient and not a benefit for the environment. The real value lies in separating the clean from the contaminated, in a cost efficient process.

Understanding what’s in the mud

Through sampling and testing across harbour locations, we’re analysing sediment in detail. First, it’s excavated,then we use hydrocyclones to separate the sediment by grain size and density, allowing us to identify the chemicals and heavy metals bound to different grain sizes. This process helps identify fractions with low or high contamination levels.

It’s a practical way to turn sediment into data and ultimately make smarter, more sustainable decisions about what to reuse and what to discard.

Wouldn’t it be fantastic if most pollutants are tied to specific grains sizes, allowing us remove these grains from the sludge would then remove most of the pollutants?

Hard work, clear impact

“There’s no automation here. It’s sampling, sorting and evaluating by hand. But that’s where value is created – knowledge gathering is the foundation for smart decisions” says Torben Tang, IPUs seasoned expert in material science.
Who have nurtured many smart innovations during his 20 years of RnD projects at IPU.

And the benefit is clear

  • Lower costs for municipalities and contractors
  • Reduced environmental burden from dredging
  • A better basis for future sediment policies and decisions

Curious about how hydrocyclones and chemical analysis can support your sustainability goals?
Reach out. We’re always up for a dirty challenge.

This work is part of the project Fraktionering og Oprensning af Marine Sedimenter, supported by the MUDP programme under the Danish Ministry of the Environment.