Algae cultivation in plastic tubes compared to tubular glass photobioreactors
Algae can be cultivated in open or closed photobioreactors (PBR). The main difference between these two approaches is whether the algae solution is separated from harmful environmental influences (closed systems) or not (open systems).
Closed PBRs are available in different varieties. They differ in terms of the type of container that the algae should proliferate. The most common types of cultivation are in plastic bags, flat panel reactors and tubular reactors. The containers of flat panel and tubular reactors can be made of different materials. Either disposable polymer or sustainable glass can be used.
Tubular photobioreactors exist in laboratory and production sizes, as they are the only systems that are able to produce high quality biomass for cost efficient production of high-end algae products such as DHA, astaxanthin and spirulina.
This type of PBR makes it possible to plan production reliably with respect to the processes, yields and quality. In addition, they are especially productive due to their ability to perfectly use available floor space and light radiation. They are also relatively easy to clean.
How a tubular PBR works
Within a typical tubular PBR, several tube segments (often up to 10) are connected with each other in one horizontal row. At the end of such a row, a U-bend or manifold connects to the next higher or lower row of tubing. Several of these rows are stacked in racks. In most cases, a pump moves the algae culture through the tubular system, after which, the culture is collected in a tank and recycled again into the tubular system. In addition, a central unit supplies the algae solution with CO2 and nutrients.
In another type of system, individual pipes are installed vertically. The big advantage of this installation is that such systems work without pumps. The algae are moved through the reactor by means of the air lift principle. The tubes are connected on the top of the reactor by manifolds as well as on the bottom of the reactor by U-bends to build a closed system. Due to air injection at the bottom of every second tube, fluid circulation is generated and the air pushes the algae solution slowly to the top of the reactor. In the next tube, the algae sinks down again.
Glass tubes are used in the vast majority of tubular PBRs. Plastic tubes may also be used in a few exceptional cases. The polymer used for such tubes is typically either polyvinyl chloride (PVC) or polymethyl methacrylate (PMMA).
What to consider when choosing the most suitable method
When you are looking for the right method for cultivating algae, we would like to help you with this. Therefore, we have written a guide on the topic “Algae cultivation in plastic tubes compared to tubular glass PBR”.
Read our guide and find out how algae cultivation in tubular PBRs works. Understand the advantages and disadvantages of this cultivation method and learn in which situations algae cultivation in tubular PBRs is reasonable and in which not. Learn in particular about the differences between glass and plastic tubing in a tubular PBR and how this affects productivity and total cost of ownership.
If you would like to determine whether your intended cultivation should be inserted into a tubular PBR with glass or plastic tubing, this guide will offer helpful insights. It presents the entire range of decision relevant parameters. Through this you are provided with a complete picture of the topic.
Among other things, our guide will answer the following:
- What are the advantages and disadvantages of algae cultivation in tubular PBRs?
- For which deployment scenarios are tubular plastic PBRs in algae cultivation suitable and for which not?
- Which factors affect the total cost of ownership for algae cultivation in tubular PBRs? How does it differ with plastic or glass tubing?
- How productive is algae cultivation in tubular plastic and glass PBRs?
- What are the differences between PMMA, PVC and glass tubing?
Download your guide now: Algae cultivation in plastic tubes compared to tubular glass photobioreactors