Method, device and system for separating microalgae

Abstract

The invention relates to a method, a device and a system for separating microalgae, in particular to a method for separating the microalgae from microalgae suspension. The method comprises the following steps of: a) providing algae-containing suspension; b) adding a surfactant or solution of the surfactant into the suspension to dissolve or disperse the surfactant; c) filling bubbles from the bottom of the suspension in which the surfactant is dissolved to ensure that the bubbles are contacted with the microalgae in the rising process; d) ensuring that the microalgae are adsorbed on the bubbles to form aggregate which comprises the bubbles and the algae; e) floating the aggregate to the surface of the suspension to form a foam layer; and f) collecting the foam layer formed by the aggregate. The method, the device and the system have low equipment requirements, are economic and are favorable for scale-up production and industrial application.

Description

Technical field: [0001] The invention relates to a microalgae separation technology, in particular to a technology for separating microalgae by using a surfactant. Background technique: [0002] Microalgae are a class of individual tiny photoautotrophic and / or heterotrophic single-celled organisms, which have the characteristics of wide distribution, various species, high photosynthetic efficiency, fast growth rate, and strong adaptability. Annual CO fixation by microalgae 2 It accounts for about 40% of the global net photosynthetic output. In addition, it is rich in esters, hydrocarbons, proteins, soluble polysaccharides, and high-value natural pigments such as astaxanthin and β-carotene. Therefore, it is important in environmental protection, energy and health. Today, when the problem is attracting much attention, microalgae are getting more and more attention. [0003] The problems in the separation and collection of microalgae have always been the bottleneck restrictin...

AI Technical Summary

Problems solved by technology

[0003] The problems in the separation and collection of microalgae have always been the bottleneck restricting the development of the microalgae industry

The above-mentioned U.S. patents have the following deficiencies: First, the preparation of dissolved air water requires a dissolved air pump or a pressure-resistant storage tank, and the current domestically produced dissolved air pump produces large bubbles, which cannot achieve the ideal air flotation effect. Small micro-bubbles meet the requirements of air flotation, but the cost is higher, so this method has higher requirements on the quality of micro-bubbles and higher requirements on equipment; secondly, the final product of dissolved air flotation is the above-mentioned foam layer containing microalgae ( i.e. bubble-floc)( Figure 2d , 18) The total height is low, which is unfavorable for the water in the flocs to flow out, so that the flocs have a high water content and become liquid, and the final foam is skimmed off along the overflow port, which just confirms this point; again, the water content of the flocs obtained High still needs further dehydration treatment

Finally, because the flocs have a high water content and flow out along the overflow port, in order to fully flow out the flocs, it is necessary to adjust the height of the overflow port to be consistent with the liquid level of the algae solution, which makes the structure of the foam tower complicated.

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