Biotechnology

Tubes for algae bioreactors

In recent years, microalgae have become a rapidly growing raw material for the production of biomass (biofuel) in many countries. In the meantime, however, it has been shown that microalgae can also be used to extract important, higher-value components for applications in dietary supplements (Omega 3, etc.) and other pharmaceutical and medical areas. But for these products, uncontaminated raw materials of consistent quality are necessary. Open ponds do not offer ideal conditions for this, which is why microalgae are increasingly being grown in closed aquaculture systems.

Photosynthesis is the engine for the growth of the microalgae and photo-bioreactors have been developed to provide the necessary light that will give the microalgae the ideal, high-growth environment.

Since microalgae live in water, photo bioreactors are water containers the walls of which are translucent.

In most cases, a tube offers the best physical shape for such a purpose.

ATHEX supplies acrylic glass tubes (PMMA) for such photo bioreactors.
Our highly transparent tubes offer many technical and economical advantages:

  • PMMA pipes can be produced in many diameter gradations from Ø30 mm to Ø500 mm and in lengths up to 10 m and above
  • The specific weight of PMMA is 1.9 times lower than that of glass (a tube with a diameter of 300 mm and a wall thickness of 5 mm weighs 10.33 kg/m for glass, but only 5.52 kg/m for PMMA)
  • PMMA has a high light transmission of approx. 92%
  • PMMA is highly UV-resistant without additional coatings
  • PMMA is approved for contact with food
  • PMMA is resistant to many chemical cleaning agents and salt water
  • Experience shows that the surface of PMMA is not susceptible to biofouling
  • PMMA pipes are cost-effective

Up to a height of 10 m no coupling pieces are required

When algae and light...

create valuable substances from CO²!

Vertically installed bioreactors require significantly less space and can produce large quantities of algae biomass cost-effectively using the energy-efficient Airlift process. However, the increasing pressure on the tube wall as the water column rises must be taken into account. ATHEX has developed a patented method to regulate the wall thickness of a pipe. The wall thickness is adjusted along the tube according to the static loads resulting from the internal pressure. The internal pressure is highest in the lower part of the water column and decreases in a straight line moving up the tube.

The ATHEX process allows the thickness of the tube wall to be adapted to this decreasing pressure load. This allows material savings of up to 25% while maintaining static integrity. In addition to a significantly better environmental balance, this results in considerable cost benefits thanks to lower material costs and simpler assembly due to the reduced weight.

In recent years, ATHEX has acquired extensive manufacturing expertise in the supply of acrylic tubes for bioreactors and also has the right equipment to make them.