Reclaimed water recycling system for food processing

Abstract

The utility model provides a food processing reclaimed water recycling system, relates to the technical field of wastewater treatment, and solves the technical problem that the existing food processing wastewater cannot be used for recycling removed sludge in place. The device comprises an MBR (Membrane Bioreactor) membrane tank for solid-liquid separation of wastewater, sludge discharged by the MBR membrane tank enters a fermentation bin for fermenting the sludge, the sludge enters a crystallizing pond for producing fertilizer after being fermented in the fermentation bin, a plurality of groups of inclined partition plates and rotating rollers for stockpiling are arranged in the fermentation bin, and the rotating rollers are arranged in the crystallizing pond. A spiral blade for stirring and conveying sludge and a vent hole for ventilating and conveying oxygen are arranged outside the rotating roller. Sludge removed from food wastewater treatment is subjected to fermentation treatment through the fermentation bin, sludge with complex function of nitrogen and phosphorus is discharged into the crystallizing pond after fermentation treatment, magnesium salt is added to prepare struvite (MAP) with nitrogen and phosphorus in the sludge, and organic matter and nitrogen and phosphorus in the sludge can be effectively utilized and prepared into struvite fertilizer.

Description

Technical Field

[0001] The utility model relates to the technical field of wastewater treatment, in particular to a water recycling system for food processing. Background Art

[0002] A large amount of water is required in the processing of many foods, and thus a large amount of wastewater is generated in the processing of foods. The content of the food industry is extremely complex, including production processes such as sugar making, brewing, meat, and dairy processing. There are many kinds of food and the sources of raw materials are wide. Food industry wastewater contains a large amount of organic matter and suspended solids, and has a high oil content, many heavy metal ions, large COD and BOD values, large fluctuations in water quality and water volume, high content of nitrogen and phosphorus compounds, and in some cases, high water temperature.

[0003] The industrial treatment process of food processing wastewater is divided into primary treatment, secondary treatment and tertiary treatment. For food industry wastewater, primary treatment generally uses solid-liquid separation technology to remove suspended matter and floating matter in wastewater; secondary treatment is the main treatment process, generally using chemical and biological treatment technology to remove toxic substances such as organic matter in water, and generally using membrane treatment, strong oxidants and other technologies to further purify wastewater; tertiary treatment further purifies and treats the purified water after secondary treatment through physical treatment processes, such as precipitation and physical adsorption.

[0004] For example, a food processing wastewater treatment process proposed in the patent with publication number CN111943449A includes the above three treatment steps, but its treatment process is mainly for water purification, in which organic matter and nitrogen and phosphorus substances are removed, resulting in waste of resources. The simplest reuse of the sludge is to use it directly as nutrient soil and fertilizer. However, in addition to containing high phosphorus and nitrogen, it may also produce some harmful substances during the processing process, which may have a negative impact on crops if used directly for irrigation of crops. Utility Model Content

[0005] The utility model aims to provide a food processing water recycling system to solve the technical problem that the sludge extracted from the existing food processing wastewater cannot be fully recycled.

[0006] The embodiments of the present invention are implemented by the following technical solutions:

[0007] A food processing water reuse system comprises an MBR membrane pool for solid-liquid separation of wastewater, wherein sludge discharged from the MBR membrane pool enters a fermentation bin for fermenting the sludge, and the sludge enters a crystallization pool for producing fertilizer after fermentation in the fermentation bin, wherein a plurality of groups of inclined partitions and rotating rollers for stacking are arranged in the fermentation bin, and spiral blades for stirring and conveying the sludge and air holes for ventilation and oxygen supply are arranged outside the rotating roller.

[0008] By adopting the technical scheme, the sludge removed from the food wastewater treatment is fermented in a fermentation bin, the sludge is fermented step by step in the partitions in the fermentation bin, and is transported between the partitions by spiral blades. The sludge is ventilated through the air holes so that it can be fully aerobically fermented, which can decompose and remove most of the harmful substances in the sludge. After the fermentation treatment, the sludge rich in nitrogen and phosphorus is discharged into a crystallization pool, magnesium salt is added, and struvite (MAP) is prepared with the nitrogen and phosphorus in the sludge, which can effectively utilize the organic matter and nitrogen and phosphorus in the sludge to prepare it as struvite fertilizer.

[0009] Preferably, it also includes a filter press connected to the sludge outlet of the MBR membrane pool; after the filter press filters the sludge, the filter cake enters the fermentation tank, and the filtrate is recycled to the oxidation tank; after the oxidation tank aerobically treats the wastewater and the recycled filtrate, it is discharged into the drain outlet connected to the MBR membrane pool.

[0010] By adopting the technical solution, the filter press performs filter pressing treatment on the sludge, separates the solid and the liquid, and removes the water in the filter cake.

[0011] Preferably, it also includes a regulating tank for regulating the wastewater flow, the MBR membrane tank discharges concentrated water to the regulating tank for reuse, and the regulating tank discharges the wastewater and the reused concentrated water into the drain port connected to the oxidation tank.

[0012] By adopting this technical solution, the regulating tank receives concentrated water discharged from the MBR membrane tank while regulating the system flow and reuses it in the system.

[0013] Preferably, it also includes an air flotation machine for removing suspended matter from wastewater; the suspended matter removed by the air flotation machine is discharged into the filter press, and the wastewater from which the suspended matter is removed is discharged into the regulating tank.

[0014] By adopting this technical solution, the flotation machine mainly removes oil stains and floating organic matter to prevent them from sticking to the pipeline and causing blockage in the pipeline.

[0015] Preferably, it further comprises a water collection tank for collecting sewage, and the water collection tank discharges the sewage into the flotation machine.

[0016] With this technical solution, the water collection tank is set in a low-level area, which is convenient for collecting sewage from the production workshop by gravity and lifting the sewage to the treatment system through a lifting pump.

[0017] Preferably, the oxidation pond is provided with a fan, and the fan aerates the oxidation pond.

[0018] By adopting this technical solution, wind is set to aerate the oxidation pond to ensure a high oxygen content in the oxidation pond, which is convenient for the survival and reproduction of aerobic bacteria in the oxidation pond.

[0019] Preferably, it also includes a clear water tank for collecting the middle water discharged from the MBR membrane tank, and the clear water tank discharges the middle water into the fermentation bin for fermentation together with the sludge and for irrigation of crops.

[0020] By adopting this technical solution, the clear water tank adds the recycled water discharged from the MBR membrane tank to the fermentation tank for fermentation together with the sludge, and the remaining recycled water can be used for irrigating crops.

[0021] Preferably, the water collection tank is provided with a lifting pump to discharge sewage into the flotation machine.

[0022] Preferably, a ventilation pipe connected to the ventilation hole is provided in the rotating roller.

[0023] Preferably, the fermentation bin further comprises a support frame for supporting the bin body, a discharge port for discharging materials and a power device for providing rotational power to the rotating roller; the power device comprises a motor, and the motor is connected to the rotating roller via a gear set.

[0024] The technical solution of the embodiment of the utility model has at least the following advantages and beneficial effects:

[0025] 1. The utility model ferments the sludge removed from food wastewater treatment through a fermentation chamber, discharges the sludge containing nitrogen and phosphorus into a crystallization tank after fermentation, adds magnesium salt, and prepares struvite (MAP) with the nitrogen and phosphorus in the sludge, which can effectively utilize the organic matter and nitrogen and phosphorus in the sludge to prepare it as struvite fertilizer;

[0026] 2. The utility model ferments the sludge removed from the food wastewater treatment through the fermentation bin. The sludge is fermented step by step in the partitions in the fermentation bin and transported between the partitions through the spiral blades. The sludge is ventilated through the air holes to fully perform aerobic fermentation, which can decompose and remove most of the harmful substances in the sludge, making it convenient for subsequent treatment and reuse.

[0027] 3. While regulating the system flow, the regulating tank of the utility model receives concentrated water discharged from the MBR membrane tank and reuses it in the system to improve the reuse rate;

[0028] 4. The utility model adds the middle water discharged from the MBR membrane tank to the fermentation tank appropriately for fermentation together with the sludge, and the remaining middle water can be used for irrigating crops. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 A schematic diagram of the structure of a water recycling system for food processing provided in Example 1 of the utility model;

[0031] Figure 2 A schematic diagram of the structure of a fermentation bin of a water recycling system for food processing provided in Example 2 of the utility model;

[0032] Icons: 1. Water collection tank; 2. Flotation machine; 3. Equalization tank; 4. Oxidation tank; 5. MBR membrane tank; 6. Clear water tank; 7. Filter press; 8. Fermentation bin; 81. Support frame; 82. Partition; 83. Rotating roller; 84. Ventilation pipe; 85. Spiral blade; 86. Vent hole; 87. Discharge port; 88. Gear set; 89. Motor; 9. Crystallization tank. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0036] In the description of the present invention, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the application is usually placed when used. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0037] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] Example 1

[0039] A food processing water reuse system includes an MBR membrane pool 5 for solid-liquid separation of wastewater, wherein the MBR membrane pool 5 discharges sludge into a fermentation bin 8 for fermenting the sludge, and the sludge enters a crystallization pool 9 for producing fertilizer after fermentation in the fermentation bin 8, wherein a plurality of groups of inclined partitions 82 and rotating rollers 83 for stacking are arranged in the fermentation bin 8, and the rotating rollers 83 are externally provided with spiral blades 85 for stirring and conveying the sludge and air holes 86 for ventilation and oxygen supply.

[0040] By adopting the technical scheme, the sludge removed from the food wastewater treatment is fermented through the fermentation bin 8, the sludge is fermented step by step in the partition 82 in the fermentation bin 8, and is transported between the partitions 82 through the spiral blades 85. The sludge is ventilated through the air holes 86 so that it can be fully aerobically fermented, which can decompose and remove most of the harmful substances in the sludge. After the fermentation treatment, the sludge rich in nitrogen and phosphorus is discharged into the crystallization tank 9, magnesium salt is added, and struvite (MAP) is prepared with the nitrogen and phosphorus in the sludge, which can effectively utilize the organic matter and nitrogen and phosphorus in the sludge to prepare it as struvite fertilizer.

[0041] In this embodiment, the food processing is the processing of tartary buckwheat, which generates wastewater. After treatment, reclaimed water and fertilizer are obtained for irrigation and cultivation of tartary buckwheat.

[0042] In this embodiment, it also includes a filter press 7 connected to the sludge outlet of the MBR membrane pool 5; after the filter press 7 filters the sludge, the filter cake enters the fermentation tank 8, and the filtrate is recycled to the oxidation pool 4; after the oxidation pool 4 aerobically treats the wastewater and the recycled filtrate, it is discharged into the drain outlet connected to the MBR membrane pool 5.

[0043] By adopting the technical solution, the filter press 7 performs filter pressing treatment on the sludge, separates the solid and the liquid, and removes the water in the filter cake.

[0044] In this embodiment, a regulating tank 3 for regulating the wastewater flow is further included. The MBR membrane tank 5 discharges concentrated water for reuse to the regulating tank 3 . The regulating tank 3 discharges the wastewater and the reused concentrated water into a drain port connected to the oxidation tank 4 .

[0045] By adopting the technical solution, the regulating tank 3 receives concentrated water discharged from the MBR membrane tank 5 while regulating the system flow, and reuses it in the system.

[0046] In this embodiment, an air flotation machine 2 for removing suspended matter from wastewater is further included; the suspended matter removed by the air flotation machine 2 is discharged into the filter press 7 , and the wastewater from which the suspended matter is removed is discharged into the regulating tank 3 .

[0047] By adopting this technical solution, the flotation machine 2 mainly removes oil stains and floating organic matter to prevent them from sticking to the pipeline and causing blockage in the pipeline.

[0048] In this embodiment, a water collection tank 1 for collecting sewage is further included, and the water collection tank 1 discharges the sewage into the flotation machine 2 .

[0049] With this technical solution, the water collection tank 1 is arranged in a low-level area, so as to collect the sewage from the production workshop by gravity and lift the sewage into the treatment system through a lifting pump.

[0050] Example 2

[0051] The only difference between this embodiment and embodiment 1 is that, in this embodiment, the oxidation pond 4 is provided with a fan, and the fan aerates the oxidation pond 4 .

[0052] By adopting the technical solution, wind is set to aerate the oxidation pond 4 to ensure a high oxygen content in the oxidation pond 4, which is convenient for the survival and reproduction of aerobic bacteria in the oxidation pond 4.

[0053] In this embodiment, a clean water tank 6 is further included for collecting the middle water discharged from the MBR membrane tank 5. The clean water tank 6 discharges the middle water into the fermentation bin 8 for fermentation together with the sludge and for irrigation of crops.

[0054] By adopting the technical solution, the clean water tank 6 adds the middle water discharged from the MBR membrane tank 5 to the fermentation tank 8 for fermentation together with the sludge, and the remaining middle water can be used for irrigating crops.

[0055] In this embodiment, the water collection tank 1 is provided with a lifting pump to discharge sewage into the flotation machine 2 .

[0056] In this embodiment, a ventilation pipe 84 communicating with the ventilation hole 86 is disposed in the rotating roller 83 .

[0057] In this embodiment, the fermentation bin 8 also includes a support frame 81 for supporting the bin body, a discharge port 87 for discharging materials, and a power device for providing rotational power to the rotating roller 83; the power device includes a motor 89, and the motor 89 is connected to the rotating roller 83 through a gear set 88.

[0058] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A food processing water reuse system, comprising an MBR membrane tank (5) for solid-liquid separation of wastewater, characterized in that: The sludge discharged from the MBR membrane pool (5) enters a fermentation bin (8) for aerobic fermentation of the sludge. After fermentation in the fermentation bin (8), the sludge enters a crystallization pool (9) for producing fertilizer. The fermentation bin (8) is provided with a plurality of groups of inclined partitions (82) and rotating rollers (83) for stacking materials. The rotating rollers (83) are provided with spiral blades (85) for stirring and conveying the sludge and air holes (86) for ventilation and oxygen supply.

2. A food processing water reuse system according to claim 1, characterized in that: It also includes a filter press (7) connected to the sludge outlet of the MBR membrane pool (5); after the filter press (7) filters the sludge, the filter cake enters the fermentation bin (8), and the filtrate is recycled to the oxidation pool (4); the outlet of the oxidation pool (4) is connected to the MBR membrane pool (5).

3. A food processing water reuse system according to claim 2, characterized in that: It also includes a regulating tank (3) for regulating the flow of wastewater. The concentrated water discharged from the MBR membrane tank (5) is reused in the regulating tank (3). The drainage port of the regulating tank (3) is connected to the oxidation tank (4).

4. A food processing water reuse system according to claim 3, characterized in that: It also includes an air flotation machine (2) for removing suspended matter from wastewater; the suspended matter removed by the air flotation machine (2) is discharged into the filter press (7), and the wastewater from which the suspended matter is removed is discharged into the regulating tank (3).

5. A food processing water reuse system according to claim 4, characterized in that: It also includes a water collection tank (1) for collecting sewage, and the water collection tank (1) discharges the sewage into the air flotation machine (2).

6. A food processing water reuse system according to any one of claims 2 to 4, characterized in that: The oxidation pond (4) is provided with a fan, and the fan aerates the oxidation pond (4).

7. A food processing water reuse system according to any one of claims 1 to 5, characterized in that: It also includes a clear water tank (6) for collecting the grey water discharged from the MBR membrane tank (5). The clear water tank (6) discharges the grey water into the fermentation tank (8) to be fermented together with the sludge and used for irrigating crops.

8. A food processing water reuse system according to claim 5, characterized in that: The water collection tank (1) is provided with a lifting pump to discharge sewage into the air flotation machine (2).

9. A food processing water recycling system according to any one of claims 1 to 5 and 8, characterized in that: A ventilation pipe (84) communicating with the ventilation hole (86) is provided inside the rotating roller (83).

10. A food processing water recycling system according to any one of claims 1 to 5 and 8, characterized in that: The fermentation bin (8) further comprises a support frame (81) for supporting the bin body, a discharge port (87) for discharging materials, and a power device for providing rotational power to the rotating roller (83); the power device comprises a motor (89), and the motor (89) is connected to the rotating roller (83) through a gear set (88).

Images