Sondos Saad conducted research on heat exchangers as part of an SIA postdoc
'I am now a convinced asset manager'
For many companies in the canal zone in Zeeuws-Vlaanderen, heat exchangers are indispensable. These devices ensure that companies can manage heat as efficiently as possible. The same is true for Dow. In collaboration with the chemical giant from Terneuzen and the cleaning company StoneAge, lecturer-researcher Sondos Saad from the Asset Management research group conducted research on how to prevent damage to these heat exchangers during cleaning. Eugène de Kok, editor HZ Discovery
Sondos Saad, who also teaches in the Civil Engineering program, conducted the research as part of a postdoc from Regieorgaan SIA. The scheme is intended to further strengthen the interaction between research and education. "I've had ups and downs over the past two years, but I have learned a lot about practice-oriented research during this postdoc. My PhD at IHE Delft was very fundamental. I am happy that I have now delved more into this type of research. I have met a lot of people, and it is extremely valuable to bring practical examples from the research into the classroom. It enriches my lessons. You add something tangible."
‘I was quite sceptical’
She says that she has also learned a lot about asset management. “I was quite skeptical about what it is, but it is incredibly valuable. From my background in Egypt, I was used to building something from scratch. I was constantly working on implementing master plans; we had to build things where there was nothing. Here, you hardly encounter that, and maintenance is much more important. I am now a convinced asset manager. I also incorporate the principles of asset management into my teaching.”
The subject of her postdoc undoubtedly features in those lessons. The heat exchangers she examined are important for industrial companies in Zeeuws-Vlaanderen. However, these devices become fouled by deposits from the fluid that passes through them, making them less efficient. "A lot of research has been done on how to prevent these deposits, but there is no satisfactory solution yet."
Therefore, it is necessary for the pipes to be cleaned regularly. At Dow, this is done by a specialized cleaning company that uses high pressure to clean the devices. These devices are not comparable to the average Kärcher. The water jets examined by Sondos jet water at 2500 bar through the pipes of the heat exchanger. For comparison: the pressure at the deepest point of the ocean is just over 1100 bar. The water jets remove the deposits in the copper, steel, or titanium pipes but also damage them.
Potsdam
The goal of Sondos’ research was to create a model that predicts what happens to the pipes, regardless of the (material of) fouling and the material from which the pipes are made. Anyone who sees her presentation on the research, which she gave in June at the major international conference European Workshop on Structural Health Monitoring in Potsdam, knows that an enormous amount of mathematical formulas and the Buckingham Pi Theory, difficult to understand for many (including some with scientific backgrounds), were needed for that model. "But we succeeded," says Sondos, who was assisted by her colleague Padraig Naughton from the research group, among others.
The model takes into account pressure, flow rate, speed of the water jet on the heat exchanger pipes, and the type of material. The model shows what you can and cannot do during cleaning. “We give the cleaning companies options to do this or that with this or that material.” As a result, the heat exchangers last longer and continue to work well. The model was validated during tests at Dow's facilities and furhter discussed with cleaning company StoneAge in America. "With this, our model was confirmed in some respects. However, we want to conduct more experiments with other materials, perhaps in a subsequent project."