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A New Method of Unicellular Alga Concentration using Hydrogen Bubbles Photoelectroflotation Process Powered by Solar Energy

M. Shoikhedbrod

Abstract


Most of the existing unicellular algae are used to enrich closed ecosystems with pure oxygen in the process of biosynthesis. The concentrate of unicellular algae contains not only living cells, but also the full range of water-soluble metabolites, contained in their nutrient medium. The concentrate of unicellular algae can be used in any existing animal feeding systems, as well as in the production of granular feed. The most interesting is the conversion of Chlorella unicellular alga cells concentrate into crude oil or phospholipid oil in less than an hour, i.e. Chlorella unicellular alga cells concentrate is a source for the production of cheap, high-quality biofuels. Dunaliella unicellular alga is well known for its antioxidant properties due to its ability to produce carotene in large quantities, which is widely used in medicine, in the production of cosmetic and dietary supplements, as well as a high concentration of glycerin. However, existing methods for concentration of these algae are not economically viable due to the use of expensive centrifugation or microfiltration. The article presents the application of a new developed method of hydrogen-bubble photoelectroflotation and a specially developed complex: photoelectrolyzer + flotation cell to obtain a high-quality foam concentrate of cells of unicellular algae Chlorella or Dunaliella, using solar energy effect on a silicon semiconductor with attached non-corrosive mesh anode, immersed in water of photoelectrolyzer that creates a potential difference between the mesh anode and the cathode, located in the lower part of the photoelectrolyzer, which contributes to the photoelectrolysis of water, as a result of which electrolytic hydrogen bubbles with a calculated dispersion are formed on the cathode, which, getting from the photoelectrolyzer into a nutrient medium with unicellular algae Chlorella or Dunaliella cells of separate flotation cell, float to the free surface of the nutrient medium with unicellular algae Chlorella or Dunaliella cells, meet these cells on their way and form strong complexes of electrolytic hydrogen bubbles + unicellular algae Chlorella or Dunaliella cells. Due to the increased lifting volume, the resulting complexes float to the free surface of the nutrient medium with unicellular algae Chlorella or Dunaliella cells, from where, in the form of highly concentrated foam with unicellular algae Chlorella or Dunaliella cells, are collected in a collector quickly and economically. Electrolytic hydrogen bubbles, formed in the photoelectrolyzer during flotation process, floating to the surface of the nutrient medium with unicellular algae Chlorella or Dunaliella cells in the flotation cell, saturate the aqueous component of the nutrient medium, turning it into a negatively charged catholyte of the nutrient medium, which, as was established by the author, sharply accelerates the metabolism of unicellular algae Chlorella or Dunaliella cells, leading to their rapid reproduction. The electrolytic oxygen bubbles, formed during the photoelectrolysis of water on the mesh anode of the photoelectrolyzer, move through the oxygen outlet of the photoelectrolyzer to the oxygen collector for pure oxygen production.


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References


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