Five tanks, three technologies, one solution
As part of the renovation of a biogas plant in the Netherlands, SUMA implemented a customized agitation concept that is precisely tailored to the requirements of the five biogas tanks with three different types of agitators.
The plant has a total volume of around 2642.000 US gal and processes approximately 79,400 US tons of substrate per year with a dry matter content of between 8 and 14%. Feeding, consisting of animal manure and pasture products, takes place at thirty-minute intervals. In the future, 80.000 ft³/h of biogas will be produced, of which 27,000 ft³/h will be used on site for power generation via a CHP system and 53.000 ft³/h will be processed into biomethane.
End-to-end project management from a single source
As part of the plant equipment, SUMA was responsible for the technical design by its in-house engineering department, delivery, installation, and commissioning of the agitators by trained service technicians.
“Our credo ‘everything from a single source’ goes far beyond the agitator concept,” says Louis Georg, Area Sales Manager at SUMA. “All areas – from service to production and sales to the customer – are perfectly aligned. This enabled us to respond flexibly and efficiently to change requests at short notice.”
Combined agitator technologies in perfect harmony
The selection of the respective agitator types is based on the respective tank and substrate parameters as well as flow analyses using CFD simulations from SUMA.
In four of the five tanks, GIANTMIX long axis agitators and ASTRAMIX paddle agitators are used in combination. The long axis agitators installed on the sides ensure horizontal movement of the substrate thanks to their high thrust. This type of agitator is the only one in the world that can be adjusted horizontally and vertically up to +/- 30°.
Thanks to its modular design, the long axis agitator can be individually configured and is available with different geared motors from 20.0 to 25 hp, pipe lengths from 13 to 19,7 ft, and agitator blade diameters from 21.3'' - 30.7''.
The supplementary paddle agitators cause the targeted dissolution of floating and sinking layers as well as vertical mixing of the tank. The agitator is suitable for a dry matter content of up to 15%.
Flexible product portfolio for complex tank geometries
Another tank posed special challenges due to its four internal columns. Initially, it was designed exclusively with long axis agitators. CFD simulation showed, nonetheless, that the columns completely shielded the center of the tank, creating a dead zone. Thanks to SUMA's wide range of products, it was possible to use the Z-MIX central mixer as an optimization solution, ensuring that the area between the columns could also be mixed effectively. With its flow-optimized paddles, the Z-MIX ensures axial mixing effects.
The central mixer is available with a motor power of up to 75 hp and a nominal speed range of 10-60 rpm.
"As a full-range supplier of all agitator components, SUMA Rührtechnik is a globally respected partner for the implementation of customized mixing concepts. We were able to rapidly implement the requirements profile from the Netherlands in accordance with the specific features of the plant with our certified local partner and implement it in a process-reliable manner. With our product diversity and technical expertise, we pursue the goal of always developing a complete solution and ensuring customer satisfaction," adds Jörg Lueg, Head of Sales Northern and Eastern Germany.