Filtering and precipitating device for nitrocellulose wastewater

Abstract

The utility model discloses a filter and deposit device suitable for nitration cotton wastewater, including box body, the inside oblique installation of box body has detachable multistage filter screen, and multistage filter screen is by different mesh screen parallel arrangement, and the opposite sides of the top of box body are provided with water inlet and water outlet respectively, and the place near water inlet and water outlet all are provided with overflow weir respectively, and the bottom of box body is installed with conical sludge discharge hopper. The utility model discloses a filter and deposit device suitable for nitration cotton wastewater is through the inside oblique installation of box body detachable multistage filter screen, and the filtration efficiency of nitration cotton wastewater is greatly promoted, and the problem that the existing nitration cotton wastewater filter device can only intercept the large particle material in wastewater, leads to the nitration cotton scrap recovery rate low problem is solved.

Description

Technical Field

[0001] This utility model belongs to the technical field of nitrocellulose industrial wastewater recycling, and relates to a filtration and sedimentation device suitable for nitrocellulose wastewater. Background Technology

[0002] Cellulose nitrate, commonly known as nitrocellulose or nitrocellulose, is a product of the reaction between cellulose and nitric acid. It has good film-forming properties and can be used as a surface coating for materials such as metal and wood. Therefore, it is widely used in the civilian industry. Nitrocellulose is mainly used to manufacture various paints, typing wax paper, inks, varnished cloth, bottle caps, adhesives, leather oil, nail polish, ester-soluble or water-soluble coatings, ping-pong balls, piano keys and other products.

[0003] Currently, domestic nitrocellulose production uses refined cotton as raw material, which generates a large amount of wastewater during the production process. The pollutants in this wastewater are complex, mainly consisting of nitrocellulose scraps, pectin, oligosaccharides and monosaccharides, proteins and oils, organic acids or fatty acids, fatty alcohols and other organic matter. These pollutants are difficult to biodegrade, making wastewater recycling difficult. Direct treatment and discharge lead to the waste of nitrocellulose scrap resources. Therefore, it is necessary to filter and settle the wastewater.

[0004] Traditional nitrocellulose wastewater filtration devices can only intercept large particles in the wastewater, resulting in a high level of suspended solids (SS) after sedimentation. This leads to poor filtration efficiency for nitrocellulose particles, low sedimentation efficiency, and low nitrocellulose scrap recovery rates. Furthermore, their complex structure requires disassembly of the entire filtration unit for cleaning, which is time-consuming and labor-intensive. Therefore, improving the recycling of hydrated nitrocellulose, the resource-based and harmless treatment of precipitated nitrocellulose, and simplifying the structure of nitrocellulose wastewater filtration devices have become urgent problems to be solved in the field of nitrocellulose industrial wastewater recycling. Utility Model Content

[0005] The purpose of this invention is to provide a filtration and sedimentation device suitable for nitrocellulose wastewater, which solves the problem that existing nitrocellulose wastewater filtration devices can only intercept large particles in the wastewater, resulting in a low recovery rate of nitrocellulose scraps.

[0006] The technical solution adopted by this utility model is a filtration and sedimentation device suitable for nitrocellulose wastewater, including a box body, a detachable multi-stage filter screen installed at an incline inside the box body, an inlet and an outlet respectively provided on opposite sides of the top of the box body, an overflow weir provided near the inlet and outlet respectively, and a conical sludge discharge hopper installed at the bottom of the box body.

[0007] The multi-stage filter screen is composed of parallel arrangements of screens with different mesh sizes, with a spacing of 10cm to 40cm between adjacent screens.

[0008] Multi-stage filters consist of two screens with different mesh sizes spaced apart.

[0009] The multi-stage filter consists of any two of the following: 50 mesh, 100 mesh, and 150 mesh screens.

[0010] The screens that make up the multi-stage filter are fixed with support frames around the perimeter and in the middle. Symmetrical slots are fixed on the two inner sides of the main body of the box, and the screens are placed in the slots.

[0011] Filter support plates are fixed on the two inner sides of the box body, and the filter support plates are located at the bottom of the slot.

[0012] Two conical mud discharge hoppers are installed side by side at the bottom of the box body.

[0013] Each conical sludge discharge hopper has a sludge discharge port on its bottom side, and a sludge discharge valve is installed on the sludge discharge port.

[0014] The inlet is set higher than the outlet, and an inlet valve is installed at the inlet, while an outlet valve is installed at the outlet.

[0015] The overflow weir is a toothed weir.

[0016] The beneficial effects of this utility model are as follows: (1) By installing a detachable multi-stage filter screen at an angle inside the main body of the box, the filtration efficiency of nitrocellulose wastewater is greatly improved. The suspended solids (SS) in the effluent of the traditional nitrocellulose wastewater filtration device are reduced by 70%. When it is necessary to clean the screen in the filtration device, the screen to be cleaned can be pulled out directly from inside the main body of the box, which is convenient for operation. (2) The top of the box body is provided with an inlet and an outlet on opposite sides. Both the inlet and outlet are provided with overflow weirs, which improves the stability of water flow, thereby increasing the sedimentation time and improving the sedimentation efficiency, thus improving the efficiency of nitrocellulose recovery and reducing the operating and maintenance costs of the equipment. (3) The present invention is applicable to the filtration and sedimentation device for nitrocellulose wastewater. It is suitable for the treatment of nitrocellulose production wastewater reuse sedimentation and other industrial wastewater with high suspended solids, and has good application prospects. Attached Figure Description

[0017] Figure 1 This is a structural diagram of the filtration and sedimentation device for nitrocellulose wastewater according to this utility model; Figure 2 This is a left-side view of the filtration and sedimentation device for nitrocellulose wastewater according to this utility model; Figure 3 This is a right-side view of the filtration and sedimentation device for nitrocellulose wastewater according to this utility model; Figure 4 This is a top view of the filtration and sedimentation device for nitrocellulose wastewater according to this utility model; Figure 5This is a structural diagram of the screen and support frame in the filtration and sedimentation device for nitrocellulose wastewater, which is applicable to this utility model.

[0018] In the diagram, 1. Box body, 2. Screen, 3. Inlet, 4. Outlet, 5. Overflow weir, 6. Conical sludge discharge hopper, 7. Sludge discharge port, 8. Slot, 9. Filter screen support plate, 10. Support frame. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0020] Example 1 See Figure 1 and Figure 2 A filtration and sedimentation device suitable for nitrocellulose wastewater includes a housing body 1. Inside the housing body 1, a detachable multi-stage filter screen is installed at an angle. The multi-stage filter screen is composed of 50-mesh and 100-mesh screens 2 arranged alternately. Each screen is parallel to the others, and the distance between adjacent screens 2 is 10cm, which ensures the filtration of nitrocellulose debris of different particle sizes in the nitrocellulose wastewater.

[0021] The enclosure is made of PVC material and is secured with a stainless steel frame to increase the stability of the device.

[0022] The top of the main body 1 has an inlet 3 and an outlet 4 on opposite sides. An overflow weir 5 is provided near the inlet 3 and outlet 4. Both overflow weirs run through the entire width of the main body, ensuring that the filtration and sedimentation device is utilized to the maximum extent. Two conical sludge discharge hoppers 6 are installed side by side at the bottom of the main body 1, which speeds up the sludge discharge rate and reduces the floor space.

[0023] Example 2 See Figure 3 and Figure 4 A filtration and sedimentation device suitable for nitrocellulose wastewater includes a housing body 1. A detachable multi-stage filter screen is installed at an angle inside the housing body 1. An inlet 3 and an outlet 4 are respectively provided on opposite sides of the top of the housing body 1. An overflow weir 5 is provided near the inlet 3 and the outlet 4. Two conical sludge discharge hoppers 6 are installed side by side at the bottom of the housing body 1.

[0024] Overflow weirs are installed at inlet 3 and outlet 4 to minimize short-circuiting, dead zones and turbulence in the filter tank. This allows the water to flow slowly forward in an ideal state close to "piston flow", giving the nitrocellulose particles the most sufficient and stable conditions to settle. This significantly improves the sedimentation efficiency of the entire sedimentation device and the quality of the effluent, thereby improving the recovery efficiency of the nitrocellulose.

[0025] The multi-stage filter consists of 50-mesh and 150-mesh screens arranged alternately, with each screen parallel to the others and a spacing of 20cm between adjacent screens.

[0026] Example 3 A filtration and sedimentation device for nitrocellulose wastewater includes a housing body 1. Inside the housing body 1, a detachable multi-stage filter screen is installed at an incline. The inclined filter screen surface provides a natural downward force for the intercepted impurities. When the impurities are trapped on the filter screen under the impact of water flow, their own gravity will generate a component force along the incline, causing them to slide to the bottom of the tank.

[0027] Compared to horizontally placed filters, tilted settings provide a larger actual filtration area for the same floor space (projected area), resulting in a smaller impurity load per unit area of ​​the filter and a slower water flow. This not only reduces the risk of clogging but also decreases the likelihood of impurities embedding in the mesh, thereby extending the cleaning cycle.

[0028] The top of the tank body 1 has an inlet 3 and an outlet 4 on opposite sides. An overflow weir 5 is provided near the inlet 3 and the outlet 4. A conical sludge discharge hopper 6 is installed at the bottom of the tank body 1. The conical sludge discharge hopper 6 is a rectangular conical funnel.

[0029] Overflow weirs are installed at both the inlet and outlet to minimize short-circuiting, dead zones, and turbulence in the filtration tank. This allows the water to flow forward slowly in an ideal "piston flow" state, providing the nitrocellulose particles with the most sufficient and stable conditions for settling. This significantly improves the sedimentation efficiency of the entire sedimentation device and the quality of the effluent, thereby increasing the recovery efficiency of the nitrocellulose.

[0030] The multi-stage filter consists of 100-mesh and 150-mesh screens arranged alternately, with each screen parallel to the others and a spacing of 30cm between adjacent screens.

[0031] See Figure 5 The screen 2, which makes up the multi-stage filter screen, is fixed with a support frame 10 around its perimeter and in the middle. This prevents the screen from being deformed by impurities during the filtration process, thus reducing the filtration efficiency. The support frame around the perimeter and in the middle of the screen increases the screen's rigidity, thereby ensuring the structural stability of the screen during use.

[0032] The box body 1 has symmetrical slots 8 fixed on its two inner sides. The screen 2 is placed in the slots 8. When it is necessary to clean the screen in the box body, the corresponding screen can be pulled out directly from the slot. There is no need to disassemble the box body. After cleaning, it can be directly inserted into the slot to complete the installation. The operation is simple, time-saving and labor-saving.

[0033] Filter screen support plates 9 are fixed on the two inner sides of the housing body 1 respectively. The filter screen support plates 9 are located at the bottom of the slot 8, which greatly enhances the bending stiffness of the filter screen, improves the stability of equipment operation, and ensures the long-term, stable and efficient operation of the filtration device.

[0034] Example 4 A filtration and sedimentation device for nitrocellulose wastewater includes a housing body 1. A removable multi-stage filter screen is installed at an angle inside the housing body 1. An inlet 3 and an outlet 4 are respectively located on opposite sides of the top of the housing body 1. Overflow weirs 5 are located near both inlet 3 and outlet 4. A conical sludge discharge hopper 6 is installed at the bottom of the housing body 1. The conical sludge discharge hopper 6 is a rectangular conical funnel with an inclined inner wall that provides a natural sliding surface for the settled sludge. The sludge continuously accumulates in the hopper. Under its own gravity, the sludge at the bottom of the hopper is squeezed by the upper sludge, thereby removing some water and achieving static concentration, resulting in lower water content and smaller volume of the discharged sludge.

[0035] The multi-stage filter consists of 100-mesh and 150-mesh screens arranged alternately, with each screen parallel to the others and a spacing of 40cm between adjacent screens.

[0036] The screen 2, which makes up the multi-stage filter, is fixed with a support frame 10 around its perimeter and in the middle. The two inner sides of the main body 1 of the box are respectively fixed with symmetrical slots 8, and the screen 2 is placed in the slots 8.

[0037] A filter support plate 9 is fixed on each of the two inner sides of the box body 1, and the filter support plate 9 is located at the bottom of the slot 8.

[0038] Two conical sludge discharge hoppers 6 are installed side by side at the bottom of the main body 1. Each conical sludge discharge hopper 6 has a sludge discharge port 7 on its bottom side and a sludge discharge valve is installed on the sludge discharge port 7.

[0039] Example 5 A filtration and sedimentation device suitable for nitrocellulose wastewater includes a housing body 1. A detachable multi-stage filter screen is installed at an angle inside the housing body 1. An inlet 3 and an outlet 4 are respectively provided on opposite sides of the top of the housing body 1. An overflow weir 5 is provided near the inlet 3 and the outlet 4. A conical sludge discharge hopper 6 is installed at the bottom of the housing body 1. The conical sludge discharge hopper 6 is a rectangular conical funnel. A sludge discharge port 7 is provided on the bottom side of the conical sludge discharge hopper 6. A sludge discharge valve is installed on the sludge discharge port 7.

[0040] The multi-stage filter consists of 100-mesh and 150-mesh screens arranged alternately, with each screen parallel to the others and a spacing of 50cm between adjacent screens.

[0041] Compared to horizontally placed filters, tilted settings provide a larger actual filtration area within the same footprint, resulting in a smaller impurity load per unit area of ​​the filter and a slower water flow. This not only reduces the risk of clogging but also decreases the likelihood of impurities embedding in the mesh, thus extending the cleaning cycle.

[0042] The screen 2, which makes up the multi-stage filter, is fixed with a support frame 10 around its perimeter and in the middle. The two inner sides of the main body 1 of the box are respectively fixed with symmetrical slots 8, and the screen 2 is placed in the slots 8.

[0043] Filter screen support plates 9 are fixed to the two inner sides of the housing body 1, and the filter screen support plates 9 are located at the bottom of the slot 8. The filter screen support plates greatly enhance the bending stiffness of the filter screen, improve the stability of equipment operation, and ensure the long-term, stable and efficient operation of the filtration device.

[0044] The inlet 3 is positioned higher than the outlet 4. An inlet valve is installed at the inlet 3, and an outlet valve is installed at the outlet 4.

[0045] Overflow weirs are installed at both the inlet and outlet to minimize short-circuiting, dead zones, and turbulence in the filtration tank. This allows the water to flow forward slowly in an ideal "piston flow" state, providing the nitrocellulose particles with the most sufficient and stable conditions for settling. This significantly improves the sedimentation efficiency of the entire sedimentation device and the quality of the effluent, thereby increasing the recovery efficiency of the nitrocellulose.

[0046] Example 6 A filtration and sedimentation device for nitrocellulose wastewater includes a housing body 1. Inside the housing body 1, a detachable multi-stage filter screen is installed at an angle. Compared with a horizontally placed filter screen, the angled arrangement is equivalent to obtaining a larger actual filtration area with the same floor space (projected area). This results in a smaller impurity load per unit area of ​​the filter screen and a slower water flow rate. This not only reduces the risk of clogging but also reduces the possibility of impurities embedding into the mesh, thereby extending the cleaning cycle.

[0047] The top of the tank body 1 is provided with an inlet 3 and an outlet 4 on opposite sides. The bottom of the tank body 1 is provided with a conical sludge discharge hopper 6, which is a rectangular conical funnel. The bottom side of the conical sludge discharge hopper 6 is provided with a sludge discharge port 7, and a sludge discharge valve is installed on the sludge discharge port 7.

[0048] The multi-stage filter consists of 100-mesh and 150-mesh screens arranged alternately, with each screen parallel to the others and a spacing of 10cm between adjacent screens.

[0049] The screen 2, which makes up the multi-stage filter, is fixed with a support frame 10 around its perimeter and in the middle. The two inner sides of the main body 1 of the box are respectively fixed with symmetrical slots 8, and the screen 2 is placed in the slots 8.

[0050] Filter screen support plates 9 are fixed to the two inner sides of the housing body 1, and the filter screen support plates 9 are located at the bottom of the slot 8. The filter screen support plates greatly enhance the bending stiffness of the filter screen, improve the stability of equipment operation, and ensure the long-term, stable and efficient operation of the filtration device.

[0051] The inlet 3 is positioned higher than the outlet 4. An inlet valve is installed at the inlet 3, and an outlet valve is installed at the outlet 4.

[0052] Overflow weirs 5 are installed near both the inlet 3 and the outlet 4. Both overflow weirs 5 are toothed weirs. The overflow weir 5 near the inlet 3 is lower than the height of the inlet 3, while the overflow weir 5 near the outlet 4 is higher than the height of the outlet 4.

[0053] Traditional nitrocellulose wastewater filtration and sedimentation devices lack an overflow weir at the inlet. Water flows directly into the sedimentation tank from the inlet pipe, creating a jet at the inlet. This results in excessively high flow velocity near the inlet, while areas further away may become stagnant. This uneven distribution significantly shortens the actual sedimentation time of some water, reducing sedimentation efficiency. This application eliminates the overflow weir at the inlet, evenly "spreading" the water flow across the entire width of the tank. This ensures the water enters the entire sedimentation zone cross-section at a substantially uniform flow velocity and volume, creating crucial initial conditions for subsequent stable sedimentation.

[0054] Furthermore, the water flowing from the pipes carries significant kinetic energy, has a high velocity, and strong directionality, easily stirring up settled sludge and disrupting nitrified flocs. As the water flows over the overflow weir, its energy is consumed and dispersed, and the velocity rapidly decreases. This helps the water enter the filtration and sedimentation zone in a smoother, slower flow, avoiding impact on the settled sludge and promoting particle settling. Uniform influent reduces the possibility of short-circuiting due to uneven inlet velocity at the source, ensuring that all water flows have the most consistent residence time within the tank.

[0055] An overflow weir is installed at the outlet, running the entire width of the tank. This weir allows for the simultaneous and uniform collection of water from the entire surface layer, maximizing the effective volume of the sedimentation tank and improving the stability and reliability of the effluent quality. The height of the overflow weir at the outlet is fixed, determining the normal operating water level of the sedimentation tank and ensuring sufficient effective water depth. It also prevents excessively high water levels from carrying away scum or causing overflow, thereby improving the recovery efficiency of nitrocellulose debris. This utility model, a filtration and sedimentation device for nitrocellulose wastewater, can also be used as an extension of an inclined plate sedimentation tank for further filtration of the filtered wastewater, recovering the nitrocellulose debris.

Claims

1. A filtration and sedimentation device suitable for nitrocellulose wastewater, characterized in that, Includes the main body of the box (1), inside which a detachable multi-stage filter screen is installed at an incline, and the top of the main body of the box (1) is provided with an inlet (3) and an outlet (4) on opposite sides, and an overflow weir (5) is provided near the inlet (3) and the outlet (4), and a conical sludge discharge hopper (6) is installed at the bottom of the main body of the box (1).

2. The filtration and sedimentation device for nitrocellulose wastewater according to claim 1, characterized in that, The multi-stage filter screen is composed of parallel arrangement of screens (2) with different mesh sizes.

3. The filtration and sedimentation device for nitrocellulose wastewater according to claim 1 or 2, characterized in that, The multi-stage filter consists of two different mesh sizes of screens (2) spaced apart.

4. The filtration and sedimentation device for nitrocellulose wastewater according to claim 3, characterized in that, The multi-stage filter screen is composed of any two of the following: 50 mesh, 100 mesh and 150 mesh screens (2).

5. The filtration and sedimentation device for nitrocellulose wastewater according to claim 4, characterized in that, The screen (2) that makes up the multi-stage filter is fixed with a support frame (10) around its perimeter and in the middle. The box body (1) has symmetrical slots (8) fixed on its two inner sides respectively. The screen (2) is placed in the slots (8).

6. The filtration and sedimentation device for nitrocellulose wastewater according to claim 5, characterized in that, The main body (1) of the box is fixed with filter support plates (9) on its two inner sides respectively, and the filter support plates (9) are located at the bottom of the slot (8).

7. The filtration and sedimentation device for nitrocellulose wastewater according to claim 1, characterized in that, The bottom of the box body (1) has two conical mud discharge hoppers (6) installed side by side.

8. The filtration and sedimentation device for nitrocellulose wastewater according to claim 7, characterized in that, Each of the conical sludge hoppers (6) is provided with a sludge discharge port (7) on its bottom side, and a sludge discharge valve is installed on the sludge discharge port (7).

9. The filtration and sedimentation device for nitrocellulose wastewater according to claim 1, characterized in that, The inlet (3) is set higher than the outlet (4), and an inlet valve is installed in the inlet (3) and an outlet valve is installed in the outlet (4).

10. The filtration and sedimentation device for nitrocellulose wastewater according to claim 1, characterized in that, The overflow weir (5) is a toothed weir. The height of the overflow weir (5) near the inlet (3) is lower than the height of the inlet (3), and the height of the overflow weir (5) near the outlet (4) is higher than the height of the outlet (4).

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