A photobioreactor system for large-scale cultivation of oil-producing microalgae

Abstract

The invention discloses a photobioreactor system for realizing oil-producing micro alga large-scale culture, which comprises an inclined passage, a flat plate type photobioreactor, a liquid flow air lifting system, a liquid level control system and a temperature control system, wherein the low end of the inclined passage is positioned above the flat plate type photobioreactor; the liquid flow air lifting system comprises an air blowing device, a head tank and a circulating pipe; the liquid inlet of the head tank is connected with the liquid outlet of the flat plate type photobioreactor through the circulating pipe; the liquid outlet of the head tank is positioned above the high end of the inclined passage; the air outlet of the air blowing device is communicated with the circulating pipe; the liquid level control system is used for controlling the liquid level of the alga liquid in the flat plate type photobioreactor; and the temperature control system is used for controlling the temperature of the alga liquid in the flat plate type photobioreactor. In the system, the alga liquid is circulated under the action of both air lifting force and gravity, the growth and fat accumulation characteristics of the oil-producing algae are taken into full consideration, and low-cost and high-density culture of the oil-producing algae can be realized.

Description

technical field [0001] The invention relates to a photobioreactor, in particular to a photobioreactor system for realizing the large-scale cultivation of oil-producing microalgae. Background technique [0002] With the depletion of global petrochemical energy and the gradual deterioration of environmental problems, the search for a sustainable, renewable and environmentally friendly form of energy has become the focus of scientists from all over the world. Among many renewable energy sources (wind energy, geothermal energy, water energy, solar energy, and ocean energy), biodiesel has a high similarity with petrochemical diesel in terms of energy density and combustibility, and is easy to degrade, It does not contain sulfur and aromatic compounds, and is environmentally friendly, which has attracted widespread attention from all over the world. [0003] Biodiesel refers to the long-chain fatty acid alkyl monoester obtained after esterification of animal, vegetable or microbi...

AI Technical Summary

Problems solved by technology

Initial research work found that the biomass of some high-yield microalgae (Nannochloropsis sp.) can reach 8.0g L when cultured in the laboratory -1 Above, but after it is enlarged and cultivated outdoors, its biomass is less than 1.0g·L -1 , this huge drop in yield reveals the necessity of developing a photobioreactor that can be used for high-density cultivation of oleaginous microalgae

When the device is used to cultivate chlorella, the biomass of chlorella can reach 35.0g L -1 , but there are also many problems in the design of the reactor: (1) The centrifugal pump will cause some damage to some environmentally sensitive algal strains (algal strains without cell walls), so it cannot be used for the cultivation of such algal strains; (2) the research Personnel cannot observe the circulation of the algae liquid through the square metal tank, and the algae in the square metal tank cannot receive light; (3) After the volume of the square metal tank is enlarged, it will seriously affect the appearance and is not conducive to the circulation of the algae liquid; (4) The author of the system did not provide a design model that can be used for larger scale cultivation; (5) the system cannot overcome the influence of weather on microalgae cultivation; (6) the vertical height of the square metal tank is low, which is not conducive to CO 2 supplies

[0014] (1) The use of open pool photobioreactors to cultivate oleaginous microalgae has the following disadvantages: it is difficult for light to penetrate the 15-30cm liquid layer, so that the algal cells in the lower layer of the culture solution cannot receive sufficient light; in addition, the open pool photobiological It is difficult to achieve precise temperature control in the reactor; 2 The utilization rate of the algae is low; the cultivation cannot be continued during the rainy season; the circulation efficiency of the algae liquid is poor

[0015] (2) As mentioned above, the use of flat-plate photobioreactors to cultivate oleaginous microalgae also has the following disadvantages: compared with open ponds, its cultivation scale is relatively small; the impact of light attenuation is reduced by shortening the light path, It will lead to a reduction in the culture volume; it is difficult to connect reactors in series, and the investment cost is high, which limits its application

[0016] (3) Pipeline photobioreactors have certain problems in gas analysis technology, and the cooling of the reactor during outdoor cultivation will take up a lot of cultivation costs; pipeline photobioreactors mostly use diaphragm pumps to realize the circulation of algae liquid , some more sensitive microalgae (Haematococcus pluvialis, etc.) will not be able to grow normally; the construction cost of the pipeline reactor is relatively high, and its cultivation scale is relatively small, which is not suitable for the high cost of oil-producing microalgae. Density culture needs

[0017] (4) The vertical column photobioreactor has certain difficulties in series amplification technology, which cannot meet the needs of industrial production; expanding the culture volume by increasing the light path will seriously affect the lighting conditions of the algae liquid inside the reactor; and It is difficult to apply the automatic cleaning device to the vertical column photobioreactor; the circulation and temperature control of the algae liquid are also problems that need to be solved in this type of reactor

[0018] (5) The currently disclosed combined photobioreactor also has deficiencies in its design, which limits its application in large-scale production

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