U Loop Fermentor

The U-Loop Fermentor

The fermentor and its design are the most important aspects of the U-Loop production process

  1. Desgassing Unit

  2. Continual harvest of biomass

  3. CO2 outlet

  4. Nozzle pump

  5. Injections of medium

  6. Propeller pump (for moving the fluid through the loop)

  7. Cooling

  8. Static Mixers

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In traditional stirred fermentors there are problems with achieving sufficiently small bubbles (large surface area of the gas), and there is a large energy waste due to inefficient stirring of the bulk liquid. Furthermore, there are problems with cooling when upscaling.

UniProtein® is produced in a continuous fermentation process. A U-Loop fermentor with static mixers is used. The U-Loop fermentor gives a high utilization of the gases, which are carried through the loop by the liquid flow in almost plug-flow mode. The gases are introduced at the start of the loop and stay in well-mixed contact with the liquid until they are separated in the headspace (see below) at the end of the loop.

The fermentor that is to be used in UniProtein® production is based on a patented U-Loop fermentor design developed in cooperation with DTU.

A 20 m3 and a 50 m3 Nozzle U-Loop fermentor were built and tested by scientists at DTU. The Nozzle U-Loop design makes it possible to obtain a fermentation process that runs optimally with the highest possible product output (larger surface area) in the shortest possible time, i.e. 4 kg/m3/h against 1.8 kg/m3/h for traditional fermentors. There is about 30% energy saving in the Nozzle U-Loop fermentor. In addition, there is no need for mechanical stirring in the U-Loop fermentor.