Light-dark alternating type photobioreactor for sewage treatment
By using a light-dark alternating baffle photobioreactor, the metabolic processes of microorganisms are altered, improving the photosynthetic and respiration efficiency of microalgae. This solves the compatibility and separation problems of traditional microalgae wastewater treatment technologies, enabling efficient treatment and resource utilization of pollutants.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-03
- Publication Date
- 2026-03-17
AI Technical Summary
Traditional microalgae-based biological wastewater treatment technologies are easily affected by environmental conditions, have low adaptability to photobioreactors, are difficult to separate microalgae, and have poor treatment effects on recalcitrant pollutants, resulting in low treatment efficiency and low resource utilization rate.
A light-dark alternating baffle-type photobioreactor is designed. The light-dark cycle of microalgae is realized through the light-dark baffle. Combined with the baffle reactor, the metabolic process of microorganisms is changed, the efficiency of photosynthesis and respiration is improved, the growth of microalgae is promoted, and the pollutant treatment effect is improved through light-dark alternation.
It improves the efficiency of pollutant treatment, realizes the resource utilization of nitrogen and phosphorus, uses microalgae as a biomass resource to produce high-value products, and enhances the treatment effect on traditional and recalcitrant pollutants.
Smart Images
Figure CN224001200U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of sewage treatment equipment, specifically to a light-dark alternating photobioreactor for sewage treatment. Background Technology
[0002] Traditional wastewater treatment processes are highly effective at treating organic pollutants, but less so at treating inorganic pollutants such as nitrogen and phosphorus. Excessive nitrogen and phosphorus levels, along with other recalcitrant pollutants in wastewater, severely disrupt the growth of microorganisms and plants and animals, damaging the aquatic ecosystem, causing eutrophication, seriously harming the ecosystem, and even threatening human health. In traditional wastewater treatment systems, microorganisms convert organic pollutants into smaller molecules such as CO2, H2O, and organic acids through respiration. Furthermore, inorganic pollutants are removed from wastewater through physicochemical and biochemical treatment processes, with nitrogen and phosphorus being removed as nitrogen gas and phosphates.
[0003] In recent years, microalgae-based wastewater biological treatment technology has shown promising application prospects in low-carbon wastewater treatment due to its advantages such as low operating costs, ability to remove low concentrations of nitrogen and phosphorus, and conversion of inorganic carbon sources into organic carbon or energy.
[0004] However, existing technologies suffer from several limitations. Traditional microalgae-based wastewater biological treatment technologies are susceptible to environmental conditions, have low adaptability to photobioreactors, and face difficulties in microalgae separation, restricting their application in practical wastewater treatment processes. Previous studies have found that microalgae such as *Chlamydomonas* spp., *Chlorella* spp., *Scenedesmus* spp., *Desmodesmus* spp., and *Nannochloris* spp. have certain removal and resource utilization effects on recalcitrant pollutants such as antibiotics, pesticides, and hormones. While microalgae biological treatment technology can achieve the transformation and utilization of pollutants in wastewater, its effectiveness in treating increasingly serious recalcitrant pollutants remains poor.
[0005] Therefore, in order to solve the problems of low treatment efficiency, susceptibility to environmental factors, and low resource utilization rate in actual wastewater treatment, the traditional PBR system is optimized and a new photobioreactor system is designed to extend the light contact time of microalgae in the photobioreactor, so as to improve the pollutant treatment effect, shorten the hydraulic retention time, and improve the resource utilization rate of pollutants in the system. Utility Model Content
[0006] To address the shortcomings of the aforementioned technologies and the technical problems existing in traditional PBR systems, this invention, based on previous research results, designs a light-dark alternating baffle-type photobioreactor system for the resource utilization of pollutants in wastewater. This invention utilizes a light-dark cycle of baffles to achieve microalgae light-dark circulation, improving photosynthetic and respiration efficiency and promoting microalgae growth. Simultaneously, the light-dark alternation can influence the growth and metabolic processes of microorganisms, enhancing the photosynthesis and respiration of microalgae and strengthening the system's effectiveness against pollutants. This provides a light-dark alternating photobioreactor for wastewater treatment.
[0007] A further feature of this invention is a light-dark alternating photobioreactor for wastewater treatment, comprising a circulation channel, a circulation pump, a circulation pump holder, a circulation pump controller, and a simulated light source or an actual light source; the circulation channel is provided with an inlet pipe, an outlet pipe, and a water distributor, through which wastewater enters the circulation channel; the circulation pump is located within the circulation channel to drive the wastewater to mix with microalgae and circulate in a reaction.
[0008] The circulation channel has an opening facing vertically upward, and light reaction zones and dark reaction zones are spaced apart along the flow direction of the circulation channel. A light shield is provided at the opening of the dark reaction zone. The simulated light source or the actual light source shines into the circulation channel through the opening of the light reaction zone, forming an alternating light and dark effect with the dark reaction zone with the light shield.
[0009] A further feature of this invention is that the circulating channel is divided into a light-dark alternating reaction zone and a baffle reaction zone along the direction from the opening to the bottom. The baffle reaction zone is provided with several baffles at intervals along the flow direction of the circulating channel. The several baffles are arranged in an alternating manner to prevent sewage from forming turbulence.
[0010] A further feature of this invention is that the plurality of baffles includes a first baffle extending from the bottom of the flow channel toward the opening side, and a second baffle connected to the light-shielding plate and extending toward the bottom of the flow channel.
[0011] A further feature of this invention is that the circulating channel has an S-shaped racetrack structure, including an inlet end and an outlet end, and the outlet end folds back along the S-shaped racetrack structure to a position parallel and aligned with the inlet end.
[0012] A further feature of this invention is that the inlet pipe is located at the inlet end, the outlet pipe is located at the outlet end and connected to a water storage tank, and a return pipe connected to the inlet end is provided at the front end of the outlet pipe at the outlet end.
[0013] A further feature of this invention is that a sludge scraper is provided on one side of the circulation channel and the opening.
[0014] Further features of this invention: The reactor also includes a temperature controller and a liquid level controller for detecting the temperature of the wastewater in the flow channel, and the simulated light source includes multiple LED fluorescent tubes arranged horizontally and vertically.
[0015] This utility model has the following beneficial effects:
[0016] The alternating light and dark baffle-type photobioreactor combines a baffle reactor with a light-shielding plate, which alters the metabolic processes and mechanisms of microorganisms in the system. It can efficiently remove organic pollutants while controlling nitrogen and phosphorus, which are difficult to treat effectively using traditional activated sludge processes. The alternating light and dark baffle plate enhances the photosynthetic and respiration efficiency of microalgae and microorganisms, promoting the transformation and utilization of pollutants by microalgae. Simultaneously, the baffle reactor mixes pollutants in the wastewater, achieving homogenization of pollutants and microalgae within the reactor, thus improving the treatment efficiency of pollutants in the wastewater. The effluent enters a storage tank (box, barrel) through an effluent pipe to achieve algae-water separation.
[0017] The light-dark alternating baffle photobioreactor of the present invention is used to treat traditional pollutants and recalcitrant pollutants in actual wastewater, mainly targeting pollutants and recalcitrant pollutants in urban sewage and rural domestic sewage with low pollutant concentrations, as well as pollutants and recalcitrant pollutants in pretreated industrial wastewater.
[0018] (2) The alternating light and dark baffle photobioreactor not only improves wastewater treatment efficiency, but also promotes the growth and metabolism of microalgae due to its higher photosynthetic and respiration efficiencies. Simultaneously, microalgae can utilize nitrogen and phosphorus in wastewater during treatment, converting them into biomass. This achieves resource utilization of pollutants, while the separated microalgae can serve as raw materials for the production of high-value products such as biofuel, fertilizer, and feed. Furthermore, the alternating light and dark baffle photobioreactor can combine microalgae with traditional wastewater systems, thereby improving wastewater treatment efficiency.
[0019] Under the combined action of two hybrid systems, the light-dark alternating baffle photobioreactor can improve the treatment efficiency of pollutants and recalcitrant pollutants in wastewater, while utilizing the photosynthesis of microalgae to achieve the conversion and resource utilization of nitrogen and phosphorus. Furthermore, during their growth and metabolism, microalgae can construct algae-microbe systems with other microorganisms, enriching symbiotic bacteria, inhibiting the growth and accumulation of pathogenic bacteria and aerobic regrowth organisms (ARGs), thereby enhancing the photobioreactor's pollutant treatment efficiency and strengthening its conversion and utilization of recalcitrant pollutants.
[0020] It is not necessary for any product implementing this invention to simultaneously achieve all the advantages described above. It is understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this invention, the scope of which is defined by the appended claims and their equivalents. Attached Figure Description
[0021] Figure 1 The structure of this utility model embodiment Figure 1 ;
[0022] Figure 2 for Figure 1 Sectional view at point 2-1;
[0023] Figure 3 for Figure 1 Sectional view at point 2-2 in the middle;
[0024] Figure 4 for Figure 1 Sectional view at point 1-1;
[0025] Figure 5 for Figure 1 Sectional views at points 1-10 in the middle;
[0026] Figure 6 The structure of this utility model embodiment Figure 2 ;
[0027] Figure 7 The structure of this utility model embodiment Figure 3 .
[0028] The components include: 1. Inlet pipe; 2. Outlet pipe; 3. Water distributor; 4. Sunshade plate; 5. Circulation pump; 6. Circulation pump holder; 6-1. Circulation pump motor; 6-2. Circulation pump controller; 7. Sunshade plate holder; 8. Baffle; 9. Temperature controller and liquid level controller; 10. Medium carrier; 11. Sludge scraper; 13. Circulation channel.
[0029] To better illustrate this embodiment, some parts in the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual size of the product. Furthermore, the drawings are for illustrative purposes only and should not be construed as limiting this patent. Detailed Implementation
[0030] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings. Other related parts can be referred to the general design. In the absence of conflict, the embodiments and technical features in the embodiments of this application can be combined with each other to obtain new embodiments.
[0031] The present invention will now be described in detail with reference to the accompanying drawings, such as... Figure 1-7 As shown,
[0032] A light-dark alternating photobioreactor for wastewater treatment includes a circulation channel 13, a circulation pump 5, a circulation pump holder 6, a circulation pump motor 6-1, a circulation pump controller 6-2, and a simulated light source or an actual light source. The circulation channel 13 is equipped with an inlet pipe 1, an outlet pipe 2, and a water distributor 3. Wastewater enters the circulation channel 13 through the inlet pipe 1 and the water distributor 3. The circulation pump is installed inside the circulation channel 13 to drive the wastewater to mix with microalgae and circulate in a reaction.
[0033] The circulation channel 13 has an opening facing vertically upward, and light reaction zones and dark reaction zones are spaced apart along the flow direction of the circulation channel 13. A light shield 4 is provided at the opening of the dark reaction zone. The simulated light source or the actual light source shines into the circulation channel 13 through the opening of the light reaction zone, forming an alternating light and dark effect with the dark reaction zone with the light shield 4.
[0034] The circulation channel 13 is divided into a light-dark alternating reaction zone I (not shown in the figure) and a baffle reaction zone II along the direction from the opening to the bottom. The reaction zone is provided with several baffles 8 at intervals along the flow direction of the circulation channel 13. The several baffles 8 are staggered to prevent sewage from forming turbulence.
[0035] The plurality of baffles 8 include a first baffle extending from the bottom of the flow channel toward the opening side, and a second baffle connected to the light shield 4 and extending toward the bottom of the flow channel.
[0036] The circulating channel 13 has an S-shaped racetrack structure, including an inlet end and an outlet end. The outlet end folds back along the S-shaped racetrack structure to a position parallel and aligned with the inlet end.
[0037] The inlet pipe 1 is located at the inlet end, the outlet pipe 2 is located at the outlet end and connected to the external water storage tank, and the outlet end is provided with a return pipe connected to the inlet end at the front end of the outlet pipe 2.
[0038] A sludge scraper 11 is provided on one side of the circulation channel 13 and the opening.
[0039] The reactor also includes a temperature controller and a liquid level controller 9 for detecting the temperature of the wastewater in the flow channel, and the simulated light source includes multiple LED fluorescent tubes arranged horizontally and vertically.
[0040] The design concept of this utility model is as follows, including the following steps:
[0041] S1. Design a light-dark alternating plate photobioreactor, including a plate reaction zone and a light-dark alternating reaction zone;
[0042] S2. Based on the design of the light-dark alternating folding plate photobioreactor, wastewater is treated;
[0043] In S1, the alternating light and dark baffle reactor consists of a baffle reaction zone and an alternating light and dark reaction zone from bottom to top.
[0044] In the light-dark alternating folding plate reactor, the light-dark alternating reaction zone is combined with the folding plate reaction zone, the water outlet is connected to the water outlet pipe, and the water outlet is connected in series with the water storage tank.
[0045] A water distributor is installed at the front of the alternating light and dark baffle reactor to achieve uniform distribution of the incoming water in the reactor.
[0046] The light-dark alternating reaction zone is equipped with light-shielding plates at intervals, which alter the metabolic processes of microalgae and microorganisms in the system.
[0047] The light-dark alternating reaction zone is equipped with a light-shielding plate fixed to the top of the reactor to achieve light-dark cycle of the reactor;
[0048] The folded reaction zone is equipped with folded plates at intervals to achieve homogenization of microalgae and nutrients in the reactor;
[0049] The light-dark alternating folding plate photobioreactor is made entirely of opaque material, and a light source is installed at the top of the light-dark alternating folding plate photobioreactor.
[0050] Furthermore, an inlet is provided at the front of the light-dark alternating folding plate photobioreactor.
[0051] Furthermore, the light-dark alternating plate photobioreactor is equipped with a water distributor connected to the water inlet.
[0052] Furthermore, a folded plate reaction zone is provided at the bottom of the light-dark alternating zone of the light-dark alternating zone of the light-dark alternating plate photobioreactor.
[0053] Furthermore, the light-dark alternating plate photobioreactor zone uses a temperature controller and a liquid level controller to detect and control the reactor's operating temperature.
[0054] Furthermore, the upper part of the light-dark alternating folding reactor is covered by a light-shielding plate, allowing for sampling of the uncovered area for water quality testing at various stages.
[0055] See Figure 1-7A system for improving the photosynthetic efficiency of microalgae, enhancing pollutant treatment, and promoting pollutant resource utilization includes a light-dark alternating reaction zone I and a folded plate reaction zone II. The light-dark alternating folded plate photobioreactor comprises two zones: light-dark alternating reaction zone I and folded plate reaction zone II. An inlet pipe 1 connected to an inlet pump is installed at the front of the light-dark alternating raceway photobioreactor. A water distributor 3 is installed at the front of the light-dark alternating raceway photobioreactor, through which treated wastewater enters the reactor. The upper part of the light-dark alternating raceway photobioreactor is the light-dark alternating reaction zone I, and the lower part is the folded plate reaction zone II. There is no clear separation between the light-dark alternating reaction zone I and the folded plate reaction zone II. After entering the reactor, the wastewater mixes with microalgae and circulates within the raceway tank via circulation pumps 5 in different directions. The circulation pumps 5 are connected to a circulation pump holder 6, a circulation pump motor 6-1, and a circulation pump controller 6-2.
[0056] An opening is provided at the top of the alternating light and dark reaction zone I to facilitate sampling and measurement of water quality and microbial growth at each stage.
[0057] The sidewalls of the light-dark alternating raceway photobioreactor shown are made of opaque materials, such as stainless steel or concrete. A simulated or actual light source is installed above the light-dark alternating reaction zone to promote photosynthesis in microalgae. The simulated light source uses multiple horizontally and vertically arranged LED fluorescent tubes. The actual light source uses sunlight, while the simulated light source can be used as a supplementary light source at night. When there is no light at night, the LED fluorescent tubes allow the reaction zone to continuously treat wastewater during the night.
[0058] In this reactor, a light-shielding plate 4 is installed on the upper part of the light-dark alternation reaction zone I. The light-shielding plate is fixed to the upper part of the light-dark alternation reaction zone I using a light-shielding plate fixer 7 to achieve light-dark alternation in the reactor. Through light-dark alternation, the metabolic mode of microalgae in the wastewater treatment process can be changed, thereby enhancing the transformation and utilization of pollutants in wastewater by microalgae and symbiotic microorganisms.
[0059] Secondly, a baffled reaction zone II is set below the light-dark alternating reaction zone I, with baffles installed within it. The algal solution generates significant turbulence as it passes through the baffles, promoting thorough mixing and homogenization of the algal solution with nutrients in the wastewater within the reactor, thus improving wastewater treatment efficiency. Simultaneously, the S-shaped distribution of the raceway tank extends the contact time between microalgae and pollutants, enhancing the transformation and utilization of pollutants by microalgae and symbiotic microorganisms. Furthermore, a return pipe is installed before the effluent pipe at the end of the raceway tank to extend the biological residence time of microalgae, further improving the raceway tank reactor's treatment efficiency for pollutants in the wastewater.
[0060] Finally, a sludge scraper 11 is installed at the top of the light-dark alternating reaction zone I to facilitate the collection and discharge of dead and settled algae, reduce the impact of cell breakage of dead algae on the effluent quality, and improve the transformation and utilization of pollutants in wastewater by the microalgae biological treatment system.
[0061] The alternating light and dark baffled raceway photobioreactor utilizes microalgae and symbiotic microorganisms to treat traditional and recalcitrant pollutants in wastewater. By strategically placing light and dark zones in the upper part of the reactor, the metabolic mechanisms of microalgae and microorganisms can be altered. The S-shaped distribution of the alternating light and dark baffled raceway extends the illumination time, creating alternating light and dark periods in the algal solution within the reactor, thus improving the reactor's wastewater treatment efficiency. The baffled reaction zone, with its baffles, promotes turbulence in the algal solution within the reactor, homogenizing the nutrients between the microalgae and the wastewater, further enhancing the microalgae's ability to treat pollutants. Additionally, the longer raceway area extends the hydraulic retention time of the microalgae, further improving the pollutant treatment efficiency of the alternating light and dark baffled raceway photobioreactor.
[0062] The alternating light and dark folding plate photobioreactor is constructed from opaque materials such as stainless steel or concrete. During the microalgae cultivation process, half the amount of microalgae in the alternating light and dark folding plate photobioreactor is added. In continuous operation, actual wastewater is uniformly introduced into the photobioreactor through a distributor and influent pump.
[0063] The alternating light and dark folding-plate raceway photobioreactor features return pipes installed before the water distributor and the effluent pipe, allowing the algal solution to circulate within the raceway. This circulation impacts the reactor surface, reducing algal adhesion. The presence of suspended carriers promotes algal attachment and facilitates contact between pollutants and algae, enhancing the algae's effectiveness in treating pollutants. Simultaneously, LED fluorescent lights can be installed around the alternating light and dark folding-plate raceway photobioreactor as supplementary light sources for nighttime wastewater treatment, providing a suitable light environment for algal growth and metabolism.
[0064] The alternating light and dark baffled raceway reactor can improve wastewater treatment efficiency, reduce pollutant emissions, and simultaneously achieve resource utilization of pollutants and biomass conversion of microalgae. The microalgae and their metabolites collected during wastewater treatment can be collected by a sludge scraper and used as raw materials for industrial production such as feed, organic fertilizer, and biofuel.
[0065] This reactor utilizes microalgae, constructing a stable algae-bacterial system using microorganisms in the wastewater during microalgae cultivation. Alternating light and dark conditions within the reactor are achieved through a light-blocking plate, enhancing the system's treatment efficiency for both traditional and recalcitrant pollutants in the wastewater. Simultaneously, the baffles at the bottom of the reactor promote the homogenization of the microalgae, and the suspended carriers facilitate microalgae accumulation, algal collection, and contact between the algae and pollutants in the wastewater, promoting the transformation and utilization of pollutants by the microalgae. Furthermore, the S-shaped structure of the raceway extends the hydraulic and biological retention times of the microalgae, improving the reactor's treatment efficiency for both traditional and recalcitrant pollutants. Therefore, the light-dark alternating baffle-type raceway photobioreactor can enhance the system's transformation and resource utilization of both traditional and novel pollutants in wastewater, achieving the resource utilization of pollutants in wastewater.
[0066] The technical solution of this application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.
Claims
1. A photo-bioreactor for wastewater treatment using alternating light and dark, characterized in that: The reactor comprises a circulating flow channel, a circulating pump, a circulating pump holder, a circulating pump controller, and a simulated light source or an actual light source; the circulating flow channel is provided with a water inlet pipe, a water outlet pipe, and a water distributor, sewage enters the circulating flow channel from the water inlet pipe and the water distributor, and the circulating pump is arranged in the circulating flow channel to drive the sewage to mix with microalgae and circulate and react; The circulating flow channel is provided with an opening facing vertically upward, a light reaction zone, and a dark reaction zone arranged at intervals along the flow direction of the circulating flow channel, the dark reaction zone is provided with a light shielding plate at the opening, and the simulated light source or the actual light source is irradiated into the circulating flow channel from the opening of the light reaction zone to form a light-dark alternating effect with the dark reaction zone with the light shielding plate.
2. The alternating light and dark photobioreactor for wastewater treatment according to claim 1, characterized in that: The circulating flow channel is divided into a light-dark alternating reaction zone and a baffle reaction zone along the direction from the opening to the bottom, the baffle reaction zone is provided with a plurality of baffles arranged at intervals along the flow direction of the circulating flow channel, and the plurality of baffles are arranged in a staggered manner to block the sewage to form a turbulent flow.
3. The alternating light and dark photobioreactor for wastewater treatment according to claim 2, characterized in that: The plurality of baffles comprise a first baffle extending from the bottom of the flow channel to one side of the opening, and a second baffle connected with the light shielding plate and extending to one side of the bottom of the flow channel.
4. The alternating light / dark photobioreactor for wastewater treatment according to any one of claims 1 to 3, characterized in that: The circulating flow channel has an S-shaped track structure, comprising a water inlet end and a water outlet end, and the water outlet end is folded back along the S-shaped track structure to a position parallel to the water inlet end.
5. The alternating light and dark photobioreactor for wastewater treatment according to claim 4, characterized in that: The water inlet pipe is arranged at the water inlet end, the water outlet pipe is arranged at the water outlet end and externally connected with a water storage tank, and the water outlet end is provided with a backflow pipe communicating with the water inlet end at the front end of the water outlet pipe.
6. The alternating light and dark photobioreactor for wastewater treatment according to claim 5, characterized in that: A mud scraper is arranged on one side of the opening of the circulating flow channel.
7. The alternating light and dark photobioreactor for wastewater treatment according to claim 6, characterized in that: The reactor further comprises a temperature controller for detecting the temperature of sewage in the flow channel and a liquid level controller, and the simulated light source comprises a plurality of LED fluorescent lamp tubes arranged transversely and longitudinally.