Microalgae culture wastewater treatment system based on thick and thin shunting

Abstract

The utility model relates to a microalgae culture wastewater treatment system based on thick and thin flow division, which comprises a solid-liquid separation device and an anaerobic fermentation device, the solid-liquid separation device comprises a thick liquid sedimentation tank and a thin liquid sedimentation tank, and the thick liquid sedimentation tank and the thin liquid sedimentation tank are separated by a partition plate; the upper side of the concentrated liquid sedimentation tank is provided with an impurity removal filtering device, the impurity removal filtering device is provided with a shell, the inner wall of the shell is provided with two chains, a plurality of screen pieces are connected between the two chains, the inner wall of the shell is provided with a waste discharge hopper, the chains are arranged in an inclined mode, and the waste discharge hopper is provided with a water outlet. The upper chain section of the chain conveys from bottom to top, the waste discharging hopper is located below the discharging end of the upper chain section, the shell is provided with a feeding port above the feeding end of the upper chain section, and the bottom wall of the shell is provided with a liquid outlet. The whole process flow is simple, the energy consumption is low, the recycling and high-value utilization of the livestock and poultry breeding wastewater can be realized to the greatest extent, and the sewage treatment cost is reduced.

Description

Technical Field

[0001] This utility model relates to an aquaculture wastewater treatment system, specifically a microalgae aquaculture wastewater treatment system based on concentrated-dilute separation. Background Technology

[0002] Livestock farming wastewater is a complex organic wastewater, characterized by high levels of organic compounds and high levels of ammonia and phosphorus. Furthermore, its dark black color, strong pungent odor, and high content of suspended solids also pose challenges to its treatment.

[0003] In my country's rural areas, 35% to 40% of non-point source pollution from organic waste originates from livestock and poultry manure, which accounts for over 40% of the total agricultural organic waste generated annually. Livestock wastewater contains large amounts of organic matter, and direct discharge of it causes serious pollution and is also a waste of resources.

[0004] At present, livestock and poultry breeding wastewater is mostly treated by methods such as standard treatment and discharge, and agricultural irrigation. Not only are the treatment processes complicated, but they also require a large investment in construction costs and high subsequent operating costs, which puts a heavy burden on many breeding enterprises and restricts the long-term development of the livestock and poultry breeding industry. Utility Model Content

[0005] The purpose of this invention is to provide a microalgae aquaculture wastewater treatment system based on concentrated and dilute dilution. Its overall process is simple, energy consumption is low, and it can maximize the resource utilization and high-value utilization of livestock and poultry aquaculture wastewater, reduce sewage treatment costs, and achieve certain economic output.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A microalgae cultivation wastewater treatment system based on concentrated and dilute separation includes a solid-liquid separation device and an anaerobic fermentation device. The solid-liquid separation device includes a concentrated liquid sedimentation tank and a dilute liquid sedimentation tank, which are separated by a partition. The top edge of the partition is lower than the edge height of the concentrated and dilute liquid sedimentation tanks. A filtration device is installed on the upper side of the concentrated liquid sedimentation tank. The filtration device has a shell, and two chains are installed on the inner wall of the shell. Several screen plates are connected between the two chains. A waste discharge hopper is installed on the inner wall of the shell. The chains are inclined, and the upper chain segment runs from bottom to top. The conveyor and waste discharge hopper are located below the discharge end of the upper chain section. The shell has a feed inlet above the feed end of the upper chain section and a liquid outlet on the bottom wall of the shell. The liquid outlet is located above the concentrated liquid sedimentation tank. Several aeration discs are connected to the bottom wall of the dilute liquid sedimentation tank. The several aeration discs are connected by pipes. An aeration pump is fixed to the rear side of the dilute liquid sedimentation tank. The aeration pump is connected to the aeration discs by pipes. A concentrated liquid pump is located at the front side of the concentrated liquid sedimentation tank. The concentrated liquid pump is connected to a concentrated liquid extraction pipe. The concentrated liquid extraction pipe extends into the concentrated liquid sedimentation tank. The concentrated liquid discharge pipe of the concentrated liquid pump is connected to the concentrated liquid inlet of the anaerobic fermentation device.

[0008] Specifically, a dilute liquid outlet pipe is provided at the edge of the opening of the dilute liquid sedimentation tank, and the dilute liquid outlet pipe is connected to a dilute liquid outlet pump.

[0009] Specifically, the anaerobic fermentation device includes a tank, a concentrated liquid inlet located at the lower part of the side wall of the tank, a biogas outlet and a biogas outlet located at the upper part of the side wall of the tank, a stirring shaft rotatably connected to the top and bottom walls of the tank, a stirring motor located on the top wall of the tank, the stirring motor being used to drive the stirring shaft to rotate, and multiple stirring paddles fixedly mounted on the stirring shaft.

[0010] Specifically, multiple agitators are arranged axially, and each agitator has four blades, which are evenly distributed circumferentially.

[0011] Specifically, the bottom wall of the tank has an upward-protruding cone in the middle, and a lower bearing is installed in the top of the cone. The stirring shaft is rotatably connected to the lower bearing. The bottom wall edge of the tank has a discharge port, which is fan-shaped. A spiral mud discharge mechanism is fixedly connected to the lower side of the discharge port. The inner cavity of the spiral mud discharge mechanism is connected to the inner cavity of the tank. The spiral mud discharge mechanism has a spiral blade, and a discharge port is provided at one end of the shell of the spiral mud discharge mechanism.

[0012] Specifically, a mud-stirring frame is fixed to the lower end of the stirring shaft. The mud-stirring frame has three stirring frames. The top side frame bars of the three stirring frames are fixed by a ring. The inner side frame bars of the stirring frames gradually slope downward from the inside out.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0014] The aquaculture wastewater enters the impurity removal and filtration device 13 through the feed inlet 134. It flows through the screen 131 set in the upper chain section, where hair and debris are left on the screen 131. Then, it is driven by the chain 133 and sent into the waste discharge hopper 132 for discharge. The already broken-down feces in the wastewater can pass through the screen 131.

[0015] After filtration, the wastewater (including feces) flows into the concentrated sedimentation tank 11 through the outlet 135 for preliminary sedimentation. The vast majority of the solids settle at the bottom of the concentrated sedimentation tank 11, while a small portion of the solids and surface liquid flow into the dilute sedimentation tank 12.

[0016] The solid-containing concentrate at the bottom of the concentrated sedimentation tank 11 is pumped by the concentrated liquid pump 111 to the anaerobic fermentation device 2 for anaerobic fermentation treatment. This part has a high solid content and can also achieve a high gas production rate.

[0017] The low concentration of fecal matter in the dilute sedimentation tank 12 is addressed by aeration pump 122 blowing air into aeration discs 121, generating microbubbles for micro-oxygenation treatment to enhance microbial decomposition in the water. After micro-oxygenation treatment, nitrogen, phosphorus, and organic matter are removed through short-cut nitrification and denitrification, further reducing pollutant concentration and forming a biochemical liquid. This biochemical liquid is mixed with the biogas slurry from anaerobic fermentation to form a low-carbon, high-nitrogen, and high-phosphorus composite nutrient solution (for the wastewater to be treated). Adding this composite nutrient solution to the microalgae treatment process provides an inexpensive culture medium for microalgae cultivation and further removes carbon, nitrogen, and phosphorus pollutants from the composite nutrient solution through microalgae.

[0018] The biogas produced by anaerobic fermentation is separated by a membrane separator. The natural gas can be used internally or sold externally, while the high-concentration carbon dioxide can be partially used to make dry ice and partially introduced into a microalgae cultivation device to promote microalgae growth. The final separated microalgae can be purified into algal powder and algal protein, while the wastewater can be reused after disinfection. This invention features a simple overall process, low energy consumption, and maximizes the resource utilization and high-value utilization of livestock and poultry breeding wastewater, reducing wastewater treatment costs and achieving certain economic output. It is a green and low-carbon wastewater treatment process. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a microalgae cultivation wastewater treatment system based on concentrated and dilute flow separation.

[0021] Figure 2 A view of a solid-liquid separation device;

[0022] Figure 3 This is an internal view of the solid-liquid separation device;

[0023] Figure 4 View of the impurity removal and filtration device

[0024] Figure 5 A view of an anaerobic fermentation apparatus;

[0025] Figure 6 This is an external view of the tank.

[0026] Figure 7 This is a sectional view of the tank.

[0027] Figure 8 This is a partial view of the interior of the tank.

[0028] In the picture:

[0029] 1. Solid-liquid separation device; 11. Concentrated liquid sedimentation tank; 111. Concentrated liquid pump; 112. Concentrated liquid extraction pipe; 113. Concentrated liquid outlet pipe;

[0030] 12. Dilute liquid sedimentation tank; 121. Aeration disc; 122. Aeration pump; 123. Dilute liquid outlet pipe; 124. Dilute liquid outlet pump;

[0031] 13. Impurity removal and filtration device; 131. Screen; 132. Waste discharge hopper; 133. Chain; 134. Feed inlet; 135. Liquid outlet;

[0032] 2. Anaerobic fermentation device; 21. Concentrated liquid inlet; 22. Biogas slurry outlet; 23. Biogas outlet; 24. Stirring shaft; 241. Paddle; 242. Stirring frame; 243. Ring; 251. Cone; 252. Discharge port; 26. Spiral sludge discharge mechanism; 261. Spiral blade. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0034] See Figures 1 to 8A microalgae aquaculture wastewater treatment system based on concentrated and dilute separation includes a solid-liquid separation device 1 and an anaerobic fermentation device 2. The solid-liquid separation device 1 includes a concentrated liquid sedimentation tank 11 and a dilute liquid sedimentation tank 12, which are separated by a partition. The top edge of the partition is lower than the edge height of the concentrated liquid sedimentation tank 11 and the dilute liquid sedimentation tank 12.

[0035] A filtration device 13 is provided on the upper side of the concentrated liquid sedimentation tank 11. The filtration device 13 has a shell, and two chains 133 are provided on the inner wall of the shell. Several screens 131 are connected between the two chains 133. The screens 131 are arranged one after another between the two chains 133, and the two ends of each screen 131 are fixed to the two chains 133 respectively. A waste discharge hopper 132 is provided on the inner wall of the shell. The chains 133 are inclined, and the upper chain segment of the chains 133 is conveyed from bottom to top. The waste discharge hopper 132 is located below the discharge end of the upper chain segment. The shell has a feed inlet 134 above the feed end of the upper chain segment, and a liquid outlet 135 is provided on the bottom wall of the shell, which is located above the concentrated liquid sedimentation tank 11.

[0036] The bottom wall of the dilute sedimentation tank 12 is connected to several aeration discs 121, which are connected by pipes. An aeration pump 122 is fixed to the rear side of the dilute sedimentation tank 12 and is connected to the aeration discs 121 by pipes. A concentrated liquid sedimentation tank 11 is equipped with a concentrated liquid pump 111 at the front side. The concentrated liquid pump 111 is connected to a concentrated liquid extraction pipe 112, which extends into the concentrated liquid sedimentation tank 11. The concentrated liquid outlet pipe 113 of the concentrated liquid pump 111 is connected to the concentrated liquid inlet 21 of the anaerobic fermentation device 2.

[0037] Specifically, a dilute liquid outlet pipe 123 is provided at the edge of the opening of the dilute liquid sedimentation tank 12, and the dilute liquid outlet pipe 123 is connected to a dilute liquid outlet pump 124.

[0038] Specifically, the anaerobic fermentation device 2 includes a tank body, a concentrated liquid inlet 21 located on the lower part of the side wall of the tank body, and a biogas outlet 22 and a biogas outlet 23 located on the upper part of the side wall of the tank body. A stirring shaft 24 is rotatably connected to the top and bottom walls of the tank body, and a stirring motor is provided on the top wall of the tank body. The stirring motor is used to drive the stirring shaft 24 to rotate, and multiple stirring paddles are fixedly mounted on the stirring shaft 24.

[0039] Specifically, multiple agitators are arranged along the axial direction, and each agitator has four blades 241, which are evenly distributed circumferentially.

[0040] Specifically, the bottom wall of the tank has an upwardly protruding cone 251 in the middle, and the top cavity of the cone 251 has a lower bearing (not shown in the figure). The stirring shaft 24 is rotatably connected to the lower bearing. The bottom wall edge of the tank has a discharge port 252, which is fan-shaped. A spiral sludge discharge mechanism 26 is fixedly connected to the lower side of the discharge port 252. The inner cavity of the spiral sludge discharge mechanism 26 is connected to the inner cavity of the tank. The spiral sludge discharge mechanism 26 has a spiral blade 261, and one end of the shell of the spiral sludge discharge mechanism 26 has a discharge port.

[0041] Specifically, a mud-stirring frame is fixedly connected to the lower end of the stirring shaft 24. The mud-stirring frame is provided with three stirring frames 242. The top side frame bars of the three stirring frames 242 are fixedly connected by a ring 243. The inner side frame bars of the stirring frames 242 gradually slope downward from the inside to the outside.

[0042] The working principle of this utility model is as follows:

[0043] The aquaculture wastewater enters the impurity removal and filtration device 13 through the feed inlet 134. It flows through the screen 131 set in the upper chain section, where hair and debris are left on the screen 131. Then, it is driven by the chain 133 and sent into the waste discharge hopper 132 for discharge. The already broken-down feces in the wastewater can pass through the screen 131.

[0044] After filtration, the wastewater (including feces) flows into the concentrated sedimentation tank 11 through the outlet 135 for preliminary sedimentation. The vast majority of the solids settle at the bottom of the concentrated sedimentation tank 11, while a small portion of the solids and surface liquid flow into the dilute sedimentation tank 12.

[0045] The solid-containing concentrate at the bottom of the concentrated sedimentation tank 11 is pumped by the concentrated liquid pump 111 to the anaerobic fermentation device 2 for anaerobic fermentation treatment. This part has a high solid content and can also achieve a high gas production rate.

[0046] The low concentration of fecal matter in the dilute sedimentation tank 12 is addressed by aeration pump 122 blowing air into aeration discs 121, generating microbubbles for micro-oxygenation treatment to enhance microbial decomposition in the water. After micro-oxygenation treatment, nitrogen, phosphorus, and organic matter are removed through short-cut nitrification and denitrification, further reducing pollutant concentration and forming a biochemical liquid. This biochemical liquid is mixed with the biogas slurry from anaerobic fermentation to form a low-carbon, high-nitrogen, and high-phosphorus composite nutrient solution (for the wastewater to be treated). Adding this composite nutrient solution to the microalgae treatment process provides an inexpensive culture medium for microalgae cultivation and further removes carbon, nitrogen, and phosphorus pollutants from the composite nutrient solution through microalgae.

[0047] The biogas produced by anaerobic fermentation is separated by a membrane separator. The natural gas can be used internally or sold externally, while the high-concentration carbon dioxide can be partially used to make dry ice and partially introduced into a microalgae cultivation device to promote microalgae growth. The final separated microalgae can be purified into algal powder and algal protein, while the wastewater can be reused after disinfection. This invention features a simple overall process, low energy consumption, and maximizes the resource utilization and high-value utilization of livestock and poultry breeding wastewater, reducing wastewater treatment costs and achieving certain economic output. It is a green and low-carbon wastewater treatment process.

[0048] The tank contains a stirring shaft 24, and a stirring motor is installed on the top wall of the tank. The stirring motor drives the stirring shaft 24 to rotate. Multiple stirring blades are fixedly mounted on the stirring shaft 24 and arranged axially. Each stirring blade has four blades 241. The blades 241 agitate the liquid in the tank, making the liquid concentration in the tank more uniform, increasing the reaction rate, and making the reaction more complete.

[0049] A mud-stirring frame is fixed to the lower end of the stirring shaft 24. The mud-stirring frame has three stirring frames 242, which are used to stir the solids settled at the bottom of the tank to prevent them from settling. After the anaerobic fermentation process is completed, the liquid in the tank is discharged through the spiral mud-discharging mechanism 26. The stirring frames 242 sweep the solids at the bottom of the tank into the discharge port 252, and the spiral blade 261 is activated to discharge the solids that have entered the spiral mud-discharging mechanism 26.

[0050] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to preferred embodiments, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A microalgae cultivation wastewater treatment system based on concentrated / diluted flow separation, characterized in that: The system includes a solid-liquid separation device and an anaerobic fermentation device. The solid-liquid separation device comprises a concentrated liquid sedimentation tank and a dilute liquid sedimentation tank, which are separated by a partition. The top edge of the partition is lower than the edge height of the concentrated liquid sedimentation tank and the dilute liquid sedimentation tank. A filtration device is installed on the upper side of the concentrated liquid sedimentation tank. The filtration device has a shell, and two chains are installed on the inner wall of the shell. Several screen plates are connected between the two chains. A waste discharge hopper is installed on the inner wall of the shell. The chains are inclined, and the upper chain section conveys the liquid from bottom to top. The waste discharge hopper is located on the upper chain. Below the discharge end of the section, the shell has a feed inlet above the feed end of the upper chain section, and a liquid outlet on the bottom wall of the shell. The liquid outlet is located above the concentrated liquid sedimentation tank. Several aeration discs are connected to the bottom wall of the dilute liquid sedimentation tank. The several aeration discs are connected by pipes. An aeration pump is fixed to the rear side of the dilute liquid sedimentation tank. The aeration pump is connected to the aeration discs through pipes. A concentrated liquid pump is located at the front side of the concentrated liquid sedimentation tank. The concentrated liquid pump is connected to a concentrated liquid extraction pipe. The concentrated liquid extraction pipe extends into the concentrated liquid sedimentation tank. The concentrated liquid discharge pipe of the concentrated liquid pump is connected to the concentrated liquid inlet of the anaerobic fermentation device.

2. The microalgae cultivation wastewater treatment system based on concentrated-dilute separation according to claim 1, characterized in that: A dilute liquid outlet pipe is provided at the edge of the opening of the dilute liquid sedimentation tank, and the dilute liquid outlet pipe is connected to a dilute liquid outlet pump.

3. The microalgae cultivation wastewater treatment system based on concentrated-dilute separation according to claim 1, characterized in that: The anaerobic fermentation device includes a tank, with a concentrated liquid inlet located on the lower part of the side wall of the tank, and a biogas outlet and a biogas outlet located on the upper part of the side wall of the tank. A stirring shaft is rotatably connected to the top and bottom walls of the tank, and a stirring motor is installed on the top wall of the tank to drive the stirring shaft to rotate. Multiple stirring paddles are fixedly mounted on the stirring shaft.

4. The microalgae cultivation wastewater treatment system based on concentrated-dilute separation according to claim 3, characterized in that: Multiple agitators are arranged axially, and each agitator has four blades, which are evenly distributed circumferentially.

5. The microalgae cultivation wastewater treatment system based on concentrated-dilute separation according to claim 1, characterized in that: The bottom wall of the tank has an upward-protruding cone in the middle, and a lower bearing is installed in the top of the cone. The stirring shaft is rotatably connected to the lower bearing. The bottom wall edge of the tank has a discharge port, which is fan-shaped. A spiral mud discharge mechanism is fixed to the lower side of the discharge port. The inner cavity of the spiral mud discharge mechanism is connected to the inner cavity of the tank. The spiral mud discharge mechanism has a spiral blade, and a discharge port is provided at one end of the spiral mud discharge mechanism.

6. The microalgae cultivation wastewater treatment system based on concentrated-dilute separation according to claim 5, characterized in that: A mud-stirring frame is fixed to the lower end of the stirring shaft. The mud-stirring frame has three stirring frames. The top side frame bars of the three stirring frames are fixed together by a ring. The inner side frame bars of the stirring frames gradually slope downward from the inside out.

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