Comprehensive Oilgae Report

A detailed report on all aspects of the algae fuel value chain, the Comprehensive Oilgae Report will be of immense help to those who are on the threshold of investing in algae biofuels. More ››

Algae-based Wastewater Treatment

Compiled by a diverse team of experts, with experience in scientific and industrial fields, the Comprehensive Report for Wastewater Treatment Using Algae is the first report that provides in-depth analysis and insights on this important field. It uses innumerable data and information from a wide variety of expert sources and market studies, and distills these inputs and data into intelligence and a roadmap that you can use. More ››

Comprehensive Guide for Algae-based Carbon Capture

A Comprehensive Guide for Entrepreneurs and Businesses Who Wish to get a Basic Understanding of the Business Opportunities and Industry Dynamics of the Algae-based CO2. More ››


Comprehensive Report on Attractive Algae Product Opportunities

This is for entrepreneurs and businesses who wish to get a basic understanding of the algae fuel business and industrThe report provides an overview of the wide range of non-fuel applications of algae – both current and future prospects. It will provide entrepreneurs with an idea of how to derive more benefits from their algal energy ventures. The report provides detailed case studies, success stories and factoids of companies that have been involved in the algae products venture. More ››

Comprehensive Castor Oil Report

There is no other comprehensive report available for castor oil anywhere in the world. This is the first of its kind, and currently, the only one. More ››

Bioplastics Market & Strategy Advisor

Bioplastics Market & Strategy Advisor, published by the Bioplastics Guide, is a unique guiding framework for businesses and entrepreneurs to chart a way forward provides a critical analysis of the status, opportunities & trends of the global bioplastics sector. More ››

Algae - Food and Feed

Edible Sea-weeds 

Hydrocolloids

Animal and Fish Feed

Algae-Useful Substances

Pigments

PUFAs

Vitamins

Anti-oxidants


Algae for Pollution Control

Other Novel Applications

Cultivation of Algae in Photobioreactor


Algae cultivation can be achieved in two ways: open ponds and photobioreactors (PBR). A photobioreactor is a closed equipment which provides a controlled environment and enables high productivity of algae. As it is a closed system, all growth requirements of algae are introduced into the system and controlled according to the requirements. PBRs facilitate better control of culture environment such as carbon dioxide supply, water supply, optimal temperature, efficient exposure to light, culture density, pH levels, gas supply rate, mixing regime, etc.,

Photobioreactor - How it works

Working of a photobioreactor:

Flow description:

1. From the feeding vessel, the flow progresses to the diaphragm pump which moderates the flow of the algae into the actual tube. Built into the pump is the CO2 inlet valve.

2. The photobioreactor itself is used to promote biological growth by controlling environmental parameters including light. The tubes are made of acrylic and are designed to have light and dark intervals to enhance the growth rate.

3. The photobioreactor has a built-in cleaning system that internally cleans the tubes without stopping the production.

4. After the algae have completed the flow through the photobioreactor, it passes back to the feeding vessel.  As it progresses through the hoses, the oxygen sensors determine how much oxygen has built up in the plant and this oxygen is released in the feeding vessel itself. It is also at this stage that the optical Cell Density sensor determines the harvesting rate.

5. When the algae are ready for harvesting, they pass through the connected filtering system. This filter collects the algae that are ready for processing, while the remaining algae passes back to the feeding vessel.

6. The flow continues.

Advantages of Photobioreactors

  • Cultivation of algae is in controlled circumstances, hence potential for much higher productivity
  • Large surface-to-volume ratio. PBRs offer maximum efficiency in using light and therefore greatly improve productivity. Typically the culture density of algae produced is 10 to 20 times greater than bag culture in which algaeculture is done in bags - and can be even greater.
  • Better control of gas transfer.
  • Reduction in evaporation of growth medium.
  • More uniform temperature.
  • Better protection from outside contamination.
  • Space saving - Can be mounted vertically, horizontally or at an angle, indoors or outdoors.
  • Reduced Fouling - Recently available tube self cleaning mechanisms can dramatically reduce fouling.

Covering ponds does offer some of the benefits that are offered by photobioreactors, but enclosed systems will still provide better control of temperature, light intensity, better control of gas transfer, and larger surface area-to-volume ratio. An enclosed PBR design will enhance commercial algal biomass production by keeping algae genetics pure and reducing the possibility of parasite infestation.

Disadvantages of Photobioreactors

  • Capital cost is very high. This is one of the most important bottlenecks that is hindering the progress of algae fuel industry.
  • Despite higher biomass concentration and better control of culture parameters, data accumulated in the last two decades have shown that the productivity and production cost in some enclosed photobioreactor systems are not much better than those achievable in open-pond cultures.
  • The technical difficulty in sterilizing these photobioreactors has hindered their application for algae culture for specific end-products such as high value pharmaceutical products.
General Specifications of a Photobioreactor
Data in the table are for the Aquasearch-coupled production system for photosynthetic microbes from HR Biopetroleum. Source: HR Biopetroleum

Requirements to develop a high-performance photobioreactor for algal cultivation:

  1. In order to attain high productivity, the volume of the non-illuminated parts of the reactor should be minimized.
  2. In order to ensure a high efficiency of light use by the culture, the design must provide for the uniform illumination of the culture surface and the fast mass transfer of CO2 and O2.
  3. To prevent rapid fouling of light-transmitting surfaces of reactors, photobioreactors must be frequently shut down for their mechanical cleaning and sterilization
  4. High rates of mass transfer must be attained by means that neither damage cultured cells nor suppress their growth.
  5. For the industrial-scale production of biomass, the energy consumption required for mass transfer and the arrangement of the light-receiving surface of the algal suspension must be reduced to its minimum possible.

PBRs are complex systems composed of several subsystems. The key systems are:

  • Light system
  • Optical transmission system
  • Air handling & gas exchange systems
  • Mixing system
  • Nutrient system
  • Instrumentation system
  • Electrical system


Some of the key sub-components of the above system are:

  • Oxygen & CO2 sensors
  • Temperature sensor
  • pH sensor
  • Light sensor
  • Conductivity sensor
  • Recirculation pump
  • Harvest pump
  • CO2 injection valve
  • Substrate pump
  • Filtrate recirculation valve
  • Water inlet valve purge valve
  • Connectors and hoses
  • Oxygen release system
  • PLC control panel
  • Feeding tank


Several of the subsystems of a PBR interact. For instance, the optical transmission system and gas exchange system interact via the mixing that takes place in the reaction area.


To know more about Photobioreactors, buy our Comprehensive Oilgae report with its recent updated version. List of contents under this topic include
  1. Concepts 
  2. Types of Bioreactors Used for Algae Cultivation
  3. Parts & Components
  4. Design Principles
  5. Costs
  6. PBR Manufacturers & Suppliers
  7. Photobioreactors Q&A
  8. Research Done on Bioreactors and Photobioreactors
  9. Challenges & Efforts in Photobioreactor
  10. Photobioreactor Updates and Factoids
  11. Useful Resource

Related Links:

Microalgal Photobioreactors: Scale - up and Optimization

Photobioreactor Technology for Microalgae Cultivation

Closed Photobioreactors for Microalgal Cultivation

Photobioreactors for Cultivation of Microalgae under Strong Irradiances: Modelling, Simulation and Design

High-Density Algal Photobioreactors Using Light-Emitting Diodes

Materials, geometry, and net energy ratio of tubular photobioreactors for microalgal hydrogen production

Algae Photobioreactor Design Considerations for Commercial Scale Production

https://mospace.umsystem.edu/xmlui/bitstream/handle/10355/956/Algae%20Photobioreactor%20Design%20[abstract].pdf?sequence=3

Study of light requirements of a Photobioreactor

Efficient nutrient removal from swine manure in a tubular biofilm photo-bioreactor using algae-bacteria consortia

A New Photobioreactor for Continuous Microalgal Production in Hatcheries Based on External-Loop Airlift and Swirling Flow

Microalgae Grown in Photobioreactors for Mass Production of Biofuel




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