New mixer guide
In the complex process of mixing for wastewater treatment, small errors make a big difference. But making a useful handbook for stakeholders is a balancing act.
“You must avoid the pitfalls of oversimplifying on the one hand and showing off on the other. A handbook is only a handbook if it ads real value,” says Christian Schou, Application Manager at Grundfos.
He is part of the group behind a new Grundfos handbook, “Design Recommendations for Mixing.” The wastewater experts have translated years of accumulated knowledge and complex mathematical formulas into user-friendly rules and guidelines.
“This handbook was written for everyone working with installation and optimisation of wastewater treatment plants. Not just the scholars. In a very straightforward way, it provides the insights you need to choose the right mixer and position it correctly in your specific tank. To my knowledge, this has never been done before,” he says.
In modern wastewater treatment, proper mixing is paramount and faulty installation of mixing equipment can be very bad for business.
“If you do not add enough thrust force to the tank dead zones occur and solid particles start to settle. This prevents you from utilizing the full potential of the tank, effectively reducing the speed at which you process. On top of this, the risk of vibrations increases, which might lead to mechanical overload and damage to both motor and shaft,” says Christian Schou.
“Also, you have to consider the energy factor. If the mixer is incorrectly installed, it will not operate to its full potential. And then you can add increased energy bills to your rising service costs. With the handbook, we can help our customers minimise all three risk factors.”
Grundfos designed the handbook for all stakeholders in the business – from plant managers and personnel to contractors and specifiers. It is both a diagnostic tool and a manual for new-build as well as refurbishment projects.
“Say you have a system with four mixers, one of which experiences frequent breakdowns. With the mixer handbook, you can go through the installation, sort of like a checklist, to find out what is causing the damage. You can also use it to quality check the blueprints from a contractor. Or simply to brush up on your knowledge,” Christian Schou explains.
By combining theory and practical examples, the handbook takes the reader through the basics of mixing and provides guidelines for installing, measuring and optimising performance. It also introduces the readers to the world of computational fluid dynamics (CFD), an advanced simulation model that Grundfos applies when optimizing sustainable solutions to complex applications.
“We have put a lot of effort into the models, validating their predictions in our labs and in the real world. With the CFD models, we are able to offer our customers precise positioning of their mixers in cases where the handbook alone does not suffice,” Christian Schou explains.
This handbook was written for everyone working with installation and optimisation of wastewater treatment plants. Not just the scholars
Christian Schou, Grundfos Application Manager
Knowledge at your doorstep
In order for a handbook to add value, it has to be user-friendly, operational, and, of course, easy to get one’s hands on. That is why Grundfos offers the handbook free of charge to everyone with an interest in the subject.
“Optimisation is at the heart of what we do, and it’s what we encourage our customers to do," says Christian Schou. "We hope this handbook will make it a little easier for wastewater treatment professionals to design and maintain the most cost-efficient, energy-efficient systems possible.”
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Facts on the Grundfos mixer handbook
- Written by experts for wastewater treatment professionals
- Contains theoretical insights and operational guidelines on positioning mixers in wastewater treatment plants
- Helps to optimise performance and minimise energy consumption
- Download your copy of the handbook for free.