Building photobioreactors using low cost materials is still a challenge. Efforts are being pursued by various universities and companies in this area to make cheap PBR’s

Here is an excerpt  from the Algae Fuels Community @ CleanTick on the various low cost  materials that can be used for building low cost PBR’s

#1 – PolyVinyl Chloride (PVC) – The basal and helical photostage of a helical photobioreactor are generally made of a transparent polyvinyl chloride (PVC) tube

Features & Benefits

• Polyvinyl chloride membranes containing immobilized agents have been widely documented and used to prepare membrane sensors in photobioreactors.
• The unique UV blocking technology prevents harmful ultraviolet light wavelengths from penetrating the PVC while allowing beneficial light wavelengths to pass through the PVC clear pipe.
• The advantages include corrosion resistance, non-conductivity and light weight construction. Using specialty clear PVC piping is beneficial in the use of photobioreactors since clarity is critical in allowing as much light into the process to allow the algae to grow and feed.

Disadvantages

• Flexible PVC tubing has been used, but because of the damaging UV rays the PVC tends to break down and get brittle.
• PVC when attacked by UV rays on conventional PVC will discolor the surface of the pipe preventing or limiting the light from getting to the medium.

#2-  High Density polyethylene (HDPE)

High Density Polypropylene is used in bag photobioreactors to overcome the problems in using LDPE for algal cultivation.

Features & Benefits

• HDPE is the most promising plastic used for algal cultivation since it is cheap and commercially viable
• HDPE would cost approximately only one-third that of the current plastic materials used
• The HDPE employed reactors are found to produce algae with oil content 1% higher than that of the reinforced LDPE films.
• The opaqueness of HDPE help prevent photooxidative damage or photoinhibition
• It is also less prone to biofouling (build-up of layer of algae that blocks some of the sunlight from getting through)

Disadvantages

• HDPE is not quite as good as LDPE or the five-layer plastic as it is difficult to weld and hence show less tensile strength

Details on the other low cost materials that can be used to build cheap PBR’s from here – http://www.cleantick.com/users/dunkenneth/pages/materials-in-use-to-built-closed-loop-reactors