; Engineering, Chemical
Algae are very large and diverse groups of simple, autotrophic organisms, ranging from unicellular to multicellular form. Most of them can conduct photosynthesis, in which the CO2 and solar energy are transformed into sugar, subsequently become biomass. The ability of certain species of blue-green algae (also called cyanobacteria) carry out both photosynthesis and nitrogen fixation, which provide them ecological and agricultural advantages as a new type of bio-fertilizer, which can improve soil structure, especially saline-alkaline soil, and increase the yielding and quality of crops. These algae can also sequester CO2 emitted from the industry or electric generation plant. Furthermore, the biomass of algae will increase over 30 times in rice filed at the right conditions; therefore the capacity of CO2 sequestration is dramatically increased. In this communication, the principle and the research progress of algal bio-fertilizer in the world, especially in China were reviewed. The capacity of CO2 sequestration by algal bio-fertilizer and the technical problems of algal bio-fertilizer were also discussed. (C) 2015 Elsevier Ltd. All rights reserved.