Modular Photobioreactors System for the Cultivation of Algae

Abstract

The present invention relates to a modular system of closed photobioreactors, intended for indoor operation with LED lighting, in an uninterrupted and completely automated manner, with continuous monitoring of process variables, and feedback control of the CO.sub.2 and nutrients, of water temperature along the entire route of the photobioreactor, allowing maximum use of the indoor space where the system is arranged.

Claims

1. Modular system of photobioreactors for algae cultivation comprising: at least two photobioreactors, each of which comprises: a metallic structure in turn comprising: at least two tubular sections connected by one of its ends, wherein inside said tubular sections an algae cultivation is arranged and, wherein between said tubular sections there is another tubular section comprising LED-type lights and reflector bodies that reflect the light from the LED-type lights and transmit it to the tubular sections wherein the cultivation of algae is disposed, passing through their side walls.

2. The system of claim 1 wherein the tubular sections of each bioreactor, wherein the algae cultivation is arranged, have a section of trapezoidal configuration, with its lateral sides having a downwardly convergent inclination to receive light from the reflector bodies and the tubular sections of each bioreactor wherein the LED-type lights are arranged and the reflector bodies have a section of trapezoidal configuration, with its lateral sides having an upwardly convergent inclination.

3. The system of claim 1 further comprising at least two photobioreactors including a first photobioreactor and a second photobioreactor disposed above the first photobioreactor.

4. The system of claim 1 further comprising at least two photobioreactors including a first photobioreactor and a second photobioreactor disposed beside the first photobioreactor.

5. The system of claim 1 further comprising at least three photobioreactors including a first photobioreactor, a second photobioreactor and a third photobioreactor, wherein the third photobioreactor is disposed next to the first bioreactor and wherein the second bioreactor is disposed above or below the first or third photobioreactor.

6. The system of claim 3 further comprising a drainage structure disposed between the metal structure of the first photobioreactor and the metal structure of the second photobioreactor, wherein said drainage structure comprises a perforated top wall and a lower wall with a drainage hole so that the water flows through the perforated top wall to the drainage hole in case of spillage of water from the second bioreactor disposed above the first photobioreactor.

7. The system of claim 1 further comprising: supply nozzles located at the base of the tubular sections wherein the algae cultivation is arranged, a CO.sub.2 supply line, a nutrient supply line and several temperature conditioned water supply lines, which are distributed near and along the route of the tubular sections wherein the growing algae is disposed, which are connected to said supply nozzles, and are equipped with flow valves, a series of nutrient sensors detecting the need to incorporate nutrients, CO.sub.2 sensors and temperature sensors detecting the need to raise or lower the water temperature, and a control unit, which receives the signals from the sensors and which automatically operates the flow valves of the supply lines for supplying an additional amount of CO.sub.2, nutrients or temperature conditioned water to different tubular sections in which the algae cultivation is arranged, according to the needs of the cultivation process in view of the signals detected by the sensors.

8. The system of claim 7 further comprising a series of pH sensors.

9. The system of claim 7 wherein the temperature conditioned water supply lines extend separately in correspondence with the tubular sections in which the algae cultivation is arranged in each photobioreactor.

10. The system of claim 9 wherein each of the temperature conditioned water supply lines is connected to a heating unit.

11. The system of claim 1 wherein each of the tubular sections in which the algae cultivation of each photobioreactor is arranged, has at least a folding top cover relative to a lateral side that allows access to its interior.

12. The system of claim 1 wherein each photobioreactor has an initial tubular section wherein the algae cultivation is arranged equipped on its front with face a series of evenly distributed openings, intended to receive as many conduits carrying the product being introduced into the photobioreactor.

13. The system of claim 1 wherein each LED-type light comprises two types of LED, red and blue, with two different spectra, and the control unit has means regulating the activation of these lights of two types of LEDs in different tubular sections in which the cultivation of algae is arranged.

14. The system of claim 1 wherein each photobioreactor incorporates an output tubular section in which the algae cultivation is arranged, being larger than the other tubular sections in which the algae cultivation is arranged, which constitutes a storage and separation tank with upper outlets for separating the flow of oily algae, and with several lower outlets, with a greater flow area than the upper the outlets.

15. The system of claim 1 wherein each photobioreactor comprises in its upper part evenly distributed exhaust valves to facilitate the exit of excess oxygen and/or pressure.

16. The system of claim 2 further comprising at least two photobioreactors including a first photobioreactor and a second photobioreactor disposed above the first photobioreactor.

17. The system of claim 2 further comprising at least two photobioreactors including a first photobioreactor and a second photobioreactor disposed beside the first photobioreactor.

18. The system of claim 2 further comprising at least three photobioreactors including a first photobioreactor, a second photobioreactor and a third photobioreactor, wherein the third photobioreactor is disposed next to the first bioreactor and wherein the second bioreactor is disposed above or below the first or third photobioreactor.

19. The system of claim 5 further comprising a drainage structure disposed between the metal structure of the first photobioreactor and the metal structure of the second photobioreactor, wherein said drainage structure comprises a perforated top wall and a lower wall with a drainage hole so that the water flows through the perforated top wall to the drainage hole in case of spillage of water from the second bioreactor disposed above the first photobioreactor.

20. The system of claim 16 further comprising a drainage structure disposed between the metal structure of the first photobioreactor and the metal structure of the second photobioreactor, wherein said drainage structure comprises a perforated top wall and a lower wall with a drainage hole so that the water flows through the perforated top wall to the drainage hole in case of spillage of water from the second bioreactor disposed above the first photobioreactor.

Description

DESCRIPTION OF THE DRAWINGS

[0028] To complement the description being made and in order to aid a better understanding of the characteristics of the invention according to a preferred practical embodiment thereof, attached as an integral part of said description, is a set of drawings wherein by way of illustration without limiting the scope of the invention, the following has been represented:

[0029] FIG. 1 shows an elevational view of the modular system of photobioreactors of the present invention in which the arrangement of the tubular sections of the photobioreactors is observed, and the structure that surrounds them and supports both the LED-type lights and the reflectors.

[0030] FIG. 2 shows a sectional view AA of FIG. 1, wherein the storage tanks are also included at the front of the photobioreactors and the product treatment systems located at the end of the photobioreactors.

[0031] FIG. 3 shows a side view of FIG. 2.

[0032] FIG. 4 shows a view of the detail B of FIG. 3, wherein the part of the structure separating a first photobioreactor and a second photobioreactor disposed above the first photobioreactor are shown.

[0033] FIG. 5 shows an exploded view of the location of the sensors in a section of each of the photobioreactors.

PREFERRED EMBODIMENT OF THE INVENTION

[0034] Described below is a preferred embodiment of the invention, with reference to FIGS. 1 to 5 described above.

[0035] FIG. 1 shows an elevational a view of a first embodiment of the modular system of photobioreactors of the present invention formed by a first photobioreactor and a second photobioreactor disposed above the first photobioreactor, wherein each photobioreactor comprises a metal structure in turn comprising at least two tubular sections (5) connected by one of their ends, wherein the inside of said tubular sections (5) the algae cultivation is arranged and wherein between said tubular sections (5) another tubular section (25) is arranged comprising LED-type lights (11) and reflector bodies (12) reflecting light from the LED-type lights (11) and transmitting it toward the tubular sections (5) wherein the algae cultivation is arranged, passing through their side walls.

[0036] The tubular sections (5) of each bioreactor wherein the algae cultivation is arranged have a section of trapezoidal configuration, with their lateral sides having a downwardly converging inclination to receive light from said reflector bodies (12). These lateral sides are preferably made of thermal glass for better use of light. It is also possible that each of the tubular sections (5) has at least a folding top cover (13) relative to a lateral side permitting access therein. Therefore the tubular sections (25) of each bioreactor in which the LED-type lights (11) and the reflector bodies (12) are arranged, have a section of trapezoidal configuration, with its lateral sides having an upwardly convergent inclination.

[0037] In this first embodiment, the modular system of photobioreactors further comprises a drainage structure disposed between the metal structure of the first photobioreactor and the metal structure of the second photobioreactor, wherein said drainage structure comprises a perforated top wall (20) and a lower wall (21) with a drainage hole (22) so that the water flows through the perforated top wall (20) to the drainage hole (22) in case of water spilling from the second photobioreactor disposed above the first photobioreactor.

[0038] In a second embodiment, the photobioreactors are arranged side by side.

[0039] In a third embodiment, a combination of the first and second embodiment, the system comprises at least three photobioreactors which include a first photobioreactor, a second and a third photobioreactor photobioreactor, wherein the third bioreactor is arranged beside the first bioreactor and wherein the second bioreactor is disposed above or below the first or third photobioreactor.

[0040] The modular system of photobioreactors is arranged within a facility in which there is the main tank or incubator (1) containing dechlorinated water, algae and nutrient, saturated with a mixture of CO.sub.2, CO.sub.2 tanks (2) and a nutrient tanks (3), in correspondence with the inlet of each photobioreactor and a treatment plant (4) located at the end of the photobioreactor for the final treatment of the product.

[0041] The tubular sections (5) wherein the algae cultivation is arranged include at their base at least one supply nozzle (6), and comprising a CO.sub.2 supply line (7), a nutrient supply line (8) and several temperature conditioned water supply lines (9), which are distributed near and along the tubular conduit, which are connected to the said supply nozzles (6), as seen in greater detail in FIG. 2 and that are equipped with flow valves.

[0042] Also, each photobioreactor comprises evenly distributed tubular sections (5) wherein the algae cultivation is arranged, and a series of nutrient sensors (15) detecting the need to incorporate nutrients, CO.sub.2 sensors (16), temperature sensors (17) which detect the need to increase or decrease the water temperature and pH sensors (18), all shown in FIG. 5, and has a control unit, receiving the signals from the sensors, and automatically acting on the flow valves of the supply lines (7, 8, 9) for supplying an additional amount of CO.sub.2, nutrients or temperature conditioned water to different tubular sections (5), depending on the process needs in view of the signals detected by the sensors.

[0043] As seen in FIG. 2, the supply line of CO.sub.2 (7) is connected and feeds the CO.sub.2 tank (2) and the supply line of nutrients (8) is connected and feeds the nutrient tank (3).

[0044] Furthermore, each of the temperature conditioned water supply lines (9) extend in correspondence with different sectors of each bioreactor. Here they are distributed in correspondence with each parallel longitudinal sector of the bioreactor, as shown in FIG. 2, to establish an independent temperature regulation of each of said sectors each of said temperature conditioned water supply lines (9) being connected to a separate heating unit (10), normally located, as shown in FIG. 2, at the end of each sector positioned opposite the location of the photobioreactor inlet tubular section.

[0045] The initial tubular section (5) of each photobioreactor, which occupies the inlet position and which is reached by the product that houses the main tank (1) has a series of openings (14) evenly distributed on the front face, here being 6 in number, designed to receive as many conduits that carry product from the main tank (1) to each photobioreactor, thus facilitating uniform inlet and distribution of the product flow from the main tank (1) in each photobioreactor.