CEDA Dredging Days 2021: Sustainable Dredging And Innovation

Promotional banner of the CEDA Dredging Days 2021 (Credit: CEDA)
Promotional banner of the CEDA Dredging Days 2021 (Credit: CEDA)

Tomorrow, another event with a long tradition will start: the CEDA Dredging Days1. Due to the Covid issues, this time, it will be a virtual event, just as a lot of other regular happenings. Hopefully, it will be the last days of this dreadful period. I can’t wait to meet people again in real life. Back at the office, we are slowly starting to get back. But meetings with people far outside the regular circle were difficult. For instance, I was a member of the Technical Paper & Program Committee and the preparation was completely digital.

Home page of your CEDA Dredging Days on the Swapcard platform (Credit: CEDA)
Home page of your CEDA Dredging Days on the Swapcard platform (Credit: CEDA)

Now, the event itself is also digital. Of course, this is still not the real thing. Having a coffee and a chat in the lobby is a much more enjoyable experience than sitting in front of your screen. I have to say that with the Sawpcard platform2 selected by the organising committee, it is much easier to arrange your own program, adapted to your personal interests. Moreover, it will also facilitate meeting people with the same interest. In a sense, this might be an opportunity to approach those. In the real world, people will not get seated next to you when they have the same interest. And certainly don’t have them captioned on their chest.

Pump design workflow (inspired by Suman Sapkota)
Pump design workflow (inspired by Suman Sapkota)

As member of the TPPC, I had the opportunity of a sneak preview of the articles and presentations and I can guarantee there are a lot of interesting sessions. For starters, there are three presentations by my colleagues. Suman Sapkota will have presentation on his research in various novel methods to apply numerical research into the design of dredge pumps3. We are happy to share with you some experiences and insights on the Dredging Days.

Testing the non-radioactive density sensor
Testing the non-radioactive density sensor

Another presentation will be by Frank Bosman4. He has been active in the development of an instrument that will measure the mixture density, without using a radio-active source. This intelligent solution is not only more sustainable, but will also provide easier access to this information. If you don’t know the density, you are very likely to underperform with your dredge. He will present some experiences and data gathered on the performance of this system.

Example of recent electric DOP dredge family

Our last presentation will be by René Sens3. Less technical, but surely an interesting perspective on the future of dredging equipment. Everyone in the dredging community is aware of the necessity to change and adapt to a more sustainable approach of our dredging business. There is an urgency to reach the goals set by the UN to leave the world behind as a better place than we received it. Although usually an increase in size also increases the efficiency of a dredge, the UN goals look beyond that single parameter. With that in mind, small and medium size dredges will be far more interesting than at first sight.

Session 7: Young CEDA ask a CEO (Credit: CEDA)
Session 7: Young CEDA ask a CEO (Credit: CEDA)

There will be a lot more going on and I could produce a long list of other interesting presentations. I think you should also check out: Edwin de Hoog and Joep Goeree, Basel Yousef and Jeroen van Stappen, and if you really want to get academic: Janek Gundlach, Ebi Shahmirzadi and Arno Talmon. You can just add to your own list and see who also joins in in the audience. Other interesting sessions will be the student ‘Flash Talks’5 and the ‘Young CEDA ask a CEO’ session6 with Peter Berdovski and Kees van de Graaf. And I am very curious what the other working groups and commissions of CEDA have to present about their work.

Thursday evening is the big get together of the dredging community; meet you there! (Credit: CEDA)
Dredging Days as a they used to be: personal interaction (Credit: CEDA)

References

  1. CEDA Dredging Days 2021, CEDA
  2. CEDA Dredging Days 2021, Outsourced Events
  3. Session 5: Latest in dredging equipment and technology
  4. Session 2: Developments in modelling and measuring hydraulic transport, CEDA
  5. Session 8: Young CEDA Flash Talks
  6. Session 7: Young CEDA ask a CEO

See also

Student Interviews On Their Projects With Our Dredge Pump Slurry Test Circuit In Damen Nieuws

Damen dredge pump slurry test circuit on the outfitting quay in Nijkerk
Damen dredge pump slurry test circuit on the outfitting quay in Nijkerk

‘What sets men apart from boys is the size of their toys.’ And that wisdom applies to a lot of students that we’ve had at our company and have grown from boy to man working on our dredge pump slurry test circuit for their internship or graduation. As the test circuit has seen some intense activity these last months and yielded us with some very innovative concepts and possible new products, it was the right time to cover this interesting piece of equipment in the internal Damen Nieuws1 of January 2021 to share with all our colleagues. And that occasion in turn is an excellent opportunity to share with you the article and zoom into some of the details of the circuit.

General arrangement of the dredge pump slurry test circuit
General arrangement of the dredge pump slurry test circuit

Already more than ten years ago, we felt the need to have our own testing facility to experiment with the processes in our dredges or check the performance of new products2. After defining the specifications of the circuit, we had Hylke Visscher assisting us in designing the circuit for his internship. Subsequently he could actually supervise the manufacturing of the circuit for his graduation. Hylke worked in close cooperation with Arjan de Vries who in turn did his graduation on the building, outfitting and commissioning of the circuit. Both students from then are now esteemed and valuable colleagues as we have appreciated their performance on their projects.

After those ten years, we have a new generation of students working on the circuit. Arend van Roon recently graduated on his project with the circuit, as covered in my last post3. Currently Wim Kleermaker is preparing his experiments on the dredge pump. Upcoming is Williem Salim, not yet mentioned in the article, but now already starting his internship on the instrumentation of our laboratory. All project on the test circuit are supervised by Pieter van der Kooi as plant manager, Frank Bosman as student coordinator. Depending on the project, Ewout van Duursen, Suman Sapkota and me are supervising the student projects more on a subject level.

Various executions of a U-bend c-meter in the test circuit, for delivery and installed on a dredge
Various executions of a U-bend c-meter in the test circuit, for delivery and installed on a dredge

The odd thing you might notice in the loop of the test circuit is the U-bend directly after the dredge pump. Contrary to most first impressions, it is not to generate resistance, although it does so slightly. It is to measure how much sand has been transported. As the circuit is by nature closed, there is no way to check how much we’ve transported through the dredge pump. Sure, there is a density sensor4, but this will only indicate the so called volumetric density; how much material is there in the cross section. It will not differentiate between fast moving slurry and a slow sliding bed. In the extreme you could have a static bed, indicating a very high concentration. Multiplying this with a very high fluid speed, that is squeezed through the remaining aperture, you would expect an impressive production. Wrong! Not a single particle gets transported.

Enter: the U-bend. It measures the hydrostatic pressure differences over a certain hight in the upstream and downstream branches. This will cancel out the velocity differences but will yield the actual transported mass flow. So, that is how we can claim that we already dredged millions of cubic meters, all on the floor area of a 40 foot container flatbed.

Explanation of the U-bend measuring principle
Explanation of the U-bend measuring principle

References

  1. Testcircuit, Damen
  2. Innovation, Damen
  3. Graduation of Arend van Roon: Detecting Flow Regime And Optimising Transport Efficiency, Discover Dredging
  4. Production management, Damen

See also

A Virtual Tour Through The Dredging Experience In Damen Nieuws

Head line of the virtual tour through the Damen Dredging Experience in Damen Nieuws

One of the things I like about my work is to tell people about it and explain all the delicate details of dredging in a fashion that everybody should be able to comprehend the complexity of moving sand. I am very fortunate to work at Damen as they gave me my own museum to care for: The Damen Dredging Experience1. I’ve discussed several of the exhibits in the Experience on this website already2. Since our last appearance in the internal Damen Nieuws magazine3, the intriguing science of dredging caught the attention of the editorial board. And what better way to share our knowledge on dredging than reporting about it in our Damen Nieuws.

Here on my own website, I already introduced ‘the Experience’ about two years ago, intending to cover the various exhibits regularly. Alas, reality not always behaves as planned. There were so many other interesting items to share, or current CEDA events, or urgent requests from the service department. Well, this publication is a good incentive to continue my coverage of the Damen Dredging Experience.

First exhibit in the entrance hall: a real size DOP pump
First exhibit in the entrance hall: a real size DOP pump (Credit: Judith Korver)

One part of the experience, that does not lend itself for a very detailed explanation is the entrance to the building and the journey to the fourth floor where the experience is located. Immediately after entering the building, you may be overwhelmed by the DOP pump suspended from the ceiling. DOP pumps by themselves are not very large. But, when they are displayed out of place like inside a building, they are still formidable machines. Visitors can be introduced to the general composition of our dredging equipment with this DOP pump: it is basically a small scale dredging machine. It has a suction mouth, a dredge pump and a construction to keep everything together. Same follows for a CSD or even a hopper dredge.

Pictures about the history of The Netherlands and dredging used in the wall illustrations
Pictures about the history of The Netherlands and dredging used in the wall illustrations

Next are four floors with murals depicting topics from the dredging industry. First floor is covering the history of dredging in the Netherlands. How we always had to battle the sea to keep our land dry and tame the rivers for infrastructure. This long history made The Netherlands an excellent breeding ground for knowledge on dredging. The blooming industry is backed up by centers of excellence as the TU Delft, Marin and Deltares. With each of which we as Damen have cooperated to develop our products.

Pictures about the historical relation between Damen and dredging on the second floor
Pictures about the historical relation between Damen and dredging on the second floor

Within the Dutch dredging industry Kommer Damen played a pivotal role in the supply of auxiliary equipment to the big dredging contractors. Eventually, the company De Groot Nijkerk was acquired to also deliver dredging equipment directly.

Pictures with Damen products used in projects around the world
Pictures with Damen products used in projects around the world

Our products have been applied world wide on small and large projects. Everywhere where some wet infrastructure was developed, Damen has supplied some or more equipment. It always makes me proud to see the result of a big project and know that in some (remote indirect) way I have contributed to it.

Pictures illustrating the future of dredging industry
Pictures illustrating the future of dredging industry

The last mural is about the future of the dredging industry. One example is the increasing demand of raw materials. Beginning with the most basic of all: sand for the concrete industry. Increasingly, we see more demand for more exotic materials that are even harder to get: sea floor minerals from the abyss of the ocean. The other example is the ever increasing environmental awareness of society and the attention of cleaning up contamination and creating value for nature. Each of which our DOP pumps form the beginning is excellently purposed.

The Damen Dredging Experience is available for anyone who wants to visit, although it is best to request an appointment with one of our staff4.

Overview of the exhibits in the ‘Damen Dredging Experience’
Overview of the exhibits in the ‘Damen Dredging Experience’

References

  1. Damen Dredging Equipment in Nijkerk Officially Open, DredgingToday
  2. Dredging Experience, Discover Dredging
  3. Our Interview About New Pump Designs In The Latest Damen Nieuws
  4. Contact, Damen Dredging Equipment

See also