Solutions to photobioreactor’s tubing coupling and connection

[Global] In a tubular glass PBR, all glass tubing segments are connected to form a complete algae cultivation system.

The connection is therefore important to determine a successful cultivation cycle.

Conventional methods of connecting tubing segments

Conventionally, the tubing segments are connected using the following methods:

  1. Two ends of adjacent tubing  are pushed into a piece of silicone hose. The hose is tightened with a hose clamp.
  2. The tubing ends are pushed into a plastic hose, which is then heated using hot air. The plastic collapses onto the glass tubing tightly forming a sealed shrink sleeve.

These connection methods are associated with some serious issues:

  1. Time consuming installation.
  2. UV degradation when exposed to sunlight over time, requiring replacement.
  3. Non-reversible.
  4. Higher risk of biofouling due to dead space within the connector.

Resistance to pressure

The connection of PBR tubing must be able to hold water pressure at least 1 bar or 14.5 psi. In the photobioreactor market, not many companies could offer a good connector that withstand high pressure. Bursting from tubing connection often occur when the connection loses its flexibility and durability. The lost could be huge when bursting or even leakage occurs.

Benefits of professional couplings

Recently, professional couplings producer SCHOTT AG demonstrates a special polymers material which is more durable and reliable to connect glass tubes in PBR. This material can be quickly and easily mounted using a “twist to lock” mechanism as shown in a short video below.

From the video, we can see that the connections can be dissembled  and re-assembled from the glass tubings easily. They are also resistant to chemical cleaning agents and do not degrade under UV-radiation. By following standardized and precise mounting instructions, users can reduce dead space and thereby limits the spread of bacteria and biofouling.

Most importantly, these couplings withstand higher pressures of up to 3 bar (43.5 psi).

The innovation by SCHOTT AG continues – smaller and thinner couplings are now available, and they can hold water pressure as good as their larger counterparts. These slim versions helps PBR installation an easier and time saving job, with a reduced dead space volume and most importantly, they are more affordable.

If food grade couplings are required, these are now available as well.

Want to know more about SCHOTT’S glass tubing for photobioreactor and algae cultivation? Download the e-book for free:






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