An air floatation treatment device capable of recovering energy

Abstract

The present application relates to a kind of air floatation treatment device capable of recycling energy, including processing bucket, filter air layer and gas acceleration recovery unit from bottom to top, the bottom of processing bucket is equipped with aeration pipe, for the air floatation treatment of wastewater in processing bucket;Filter air layer is equipped with several blocks of filter adsorption material, and the pollutants in the gas rising from processing bucket to filter air layer are removed by filter adsorption material;The tail of gas acceleration recovery unit is connected with the aeration pipe by reflux pipe, and the gas accelerated after passing through gas acceleration recovery unit is recycled for aeration of processing bucket;The gas acceleration recovery unit includes the concentration part of lower part and the confluence part of upper part, the bottom of concentration part is communicated with filter air layer, the top of concentration part is communicated with confluence part, and the horizontal cross section of concentration part is not less than the horizontal cross section of confluence part, and the gas is automatically pressurized and increased flow.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, specifically relating to an air flotation treatment device capable of recovering energy. Background Technology

[0002] In dissolved air flotation (DAF) wastewater treatment technology, aeration is introduced into the bottom of the wastewater to create highly dispersed microbubbles that rise upwards. These bubbles act as carriers, adhering to pollutants in the wastewater and floating to the surface, where they are then removed. However, during DAF treatment, the wastewater still contains a significant amount of residual energy, such as thermal energy, turbulent kinetic energy of the aerated water, and residual kinetic energy of the gases produced during the flotation process. Currently, apart from thermal energy, these other forms of energy are largely not recovered or utilized, resulting in a substantial loss of energy. Furthermore, the aeration bubbles within the DAF unit carry pollutants from the water as they escape, causing odor pollution in the atmosphere. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides an air flotation treatment device capable of recovering energy. From bottom to top, it includes a treatment tank, a filter and aeration layer, and a gas acceleration and recovery unit. An aeration pipe is located at the bottom of the treatment tank for air flotation treatment of wastewater within the tank. The filter and aeration layer contains several filter adsorption materials, which remove pollutants from the gas rising from the treatment tank to the filter and aeration layer. The tail end of the gas acceleration and recovery unit is connected to the aeration pipe via a return pipe, allowing the gas accelerated by the gas acceleration and recovery unit to be reused for aeration of the treatment tank.

[0004] The gas acceleration and recovery unit includes a lower concentration section and an upper confluence section. The bottom of the concentration section is connected to the filter ventilation layer, and the top of the concentration section is connected to the confluence section. The horizontal cross-section of the concentration section is not smaller than the horizontal cross-section of the confluence section, and the gas is automatically pressurized and increased in flow.

[0005] Optionally, the air flotation treatment device is cylindrical in shape, and the treatment tank, filter air layer, concentration section and confluence section are all arranged concentrically;

[0006] The treatment tank is cylindrical, and several heat-insulating pipes are provided on the outer side of the treatment tank. The heat-insulating pipes are evenly arranged and cover the outer side of the treatment tank, and are used to introduce hot air to keep the treatment tank warm. The outlet of the heat-insulating pipe is connected to the inlet side of the aeration pipe, and the gas after the heat-insulating effect is introduced into the aeration pipe for aeration inside the treatment tank.

[0007] Optionally, the bottom of the filter ventilation layer is connected to the top of the treatment barrel, and the filter ventilation layer includes several filter adsorption materials, which are evenly distributed on the cross-section of the filter ventilation layer.

[0008] The filter adsorption material is vertically arranged and its longitudinal section is wavy; the filter adsorption material is evenly covered with air pores, and the positions of the air pores of adjacent filter adsorption materials correspond one-to-one, so that vertical and horizontal airflows are formed in the filter air layer.

[0009] Alternatively, the filter adsorption material is made of silicon carbide, which can adsorb pollutants in the airflow and play a purification role.

[0010] Optionally, a heat collection and conduction layer is provided on the outside of the filter ventilation layer, and a diversion fan is provided above the heat collection and conduction layer. The air outlet of the diversion fan is connected to the inlet of each heat insulation pipe through a diversion pipe to recover the heat energy of the gas passing through the filter ventilation layer and use it for heat preservation of the treatment tank.

[0011] Optionally, several layers of copper sheets are arranged from top to bottom inside the outer shell of the heat collection and conduction layer. The copper sheets are circular and horizontally arranged, and they surround the outer side of the filter and ventilation layer. The inner edges of all the copper sheets are in close contact with the vertical outer surface of the filter and ventilation layer. The vertical outer surface of the filter and ventilation layer is made of copper, which is beneficial to fully conduct the heat of the airflow in the filter and ventilation layer to the heat collection and conduction layer.

[0012] Optionally, the gas acceleration and recovery unit includes, from bottom to top, a buffer tank, a concentration section, a confluence section, and an outlet tank. The inner diameter of the buffer tank is smaller than the inner diameter of the filter ventilation layer, which will converge and buffer the airflow passing through the filter ventilation layer. The inner diameter of the concentration section gradually decreases from bottom to top. At least one negative pressure pipe is provided on the side of the concentration section. The concentration section is connected to the external atmospheric environment through the negative pressure pipe to increase the flow and pressure of the airflow in the concentration section.

[0013] The manifold is a vertical circular pipe, and the inner diameter of the outlet groove gradually increases from bottom to top. The top of the outlet groove is sealed and connected to the return pipe.

[0014] Further optionally, the negative pressure tube is hollow, with one end connected to the interior of the concentration section and the other end connected to the outside atmosphere through a horn opening. The horn opening is set to face downwards, and a one-way valve is set inside the negative pressure tube near the horn opening, allowing only outside air to enter the concentration section through the negative pressure tube.

[0015] Alternatively, the top of the outlet trough is connected to a return pipe via a T-shaped pipe. An aeration fan is installed on the return pipe. A shut-off valve is installed at the inlet end of the T-shaped pipe to open or close the T-shaped pipe. One end of the T-shaped pipe is connected to the return pipe, and the other end is equipped with a one-way valve to connect to the external environment, allowing only outside air to enter the T-shaped pipe.

[0016] Further optionally, the height ratio of the concentration section to the manifold is 1:(2-3), and the height ratio of the outlet trough to the manifold is 1:(3-5); the inner diameters of the bottom of the outlet trough, the manifold, and the top of the concentration section are equal, and the inner diameter of the top of the outlet trough is not greater than 1 / 3 of the inner diameter of the bottom of the concentration section.

[0017] Optionally, the top of the treatment tank is provided with a trapping screen, which is higher than the liquid level in the treatment tank. The maximum area of ​​the trapping screen can cover the cross-section of the treatment tank, and is used to filter pollutants in the rising airflow.

[0018] The inner wall of the treatment tank is provided with a groove corresponding to the height of the interception screen. The edge of the interception screen is connected to the groove by several sliders, which are evenly distributed along the circumference of the interception screen. A support rod is provided at the center of the interception screen, and the top of the support rod is connected to the filter adsorption material above to fix the center of the interception screen. When the slider moves along the groove, the coverage area of ​​the interception screen can be adjusted. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the air flotation treatment device capable of recovering energy;

[0020] Figure 2 This is a schematic diagram of a filter adsorption material.

[0021] In the attached diagram, 1-treatment tank, 2-filter and ventilation layer, 3-aeration pipe, 4-filter and adsorption material, 5-return pipe, 6-buffer tank, 7-concentration section, 8-merging section, 9-outlet tank, 10-insulation pipe, 11-ventilation hole, 12-sealing plate, 13-heat collection and conduction layer, 14-drainage fan, 15-copper sheet, 16-negative pressure pipe, 17-T-shaped pipe, 18-aeration fan. Detailed Implementation

[0022] This embodiment provides an air flotation treatment device capable of recovering energy, such as... Figures 1-2 As shown, from bottom to top, it includes a treatment tank 1, a filter and aeration layer 2, and a gas acceleration and recovery unit. The bottom of the treatment tank 1 is equipped with an aeration pipe 3 for the flotation treatment of wastewater in the treatment tank 1. The filter and aeration layer 2 is equipped with several filter adsorption materials 4. Pollutants in the gas rising from the treatment tank 1 to the filter and aeration layer 2 are filtered and removed by the filter adsorption materials 4. The tail end of the gas acceleration and recovery unit is connected to the aeration pipe 3 through a return pipe 5, so that the gas accelerated by the gas acceleration and recovery unit is reused for aeration of the treatment tank 1.

[0023] The gas acceleration and recovery unit includes a lower concentration section 7 and an upper confluence section 8. The bottom of the concentration section 7 is connected to the filter ventilation layer 2, and the top of the concentration section 7 is connected to the confluence section 8. The horizontal cross-section of the concentration section 7 is not smaller than the horizontal cross-section of the confluence section 8, and the gas is automatically pressurized and increased in flow.

[0024] Optionally, the air flotation treatment device is cylindrical in shape, and the treatment tank 1, the filter and air-permeable layer 2, the concentration section 7 and the confluence section 8 are all arranged concentrically.

[0025] The treatment tank 1 is cylindrical, and several heat-insulating pipes 10 are provided on the outer side of the treatment tank 1. The heat-insulating pipes 10 are evenly arranged and cover the outer side of the treatment tank 1, and are used to introduce hot air to keep the treatment tank 1 warm. The outlet of the heat-insulating pipe 10 is connected to the inlet side of the aeration pipe 3, and the gas after performing the heat-insulating function is input into the aeration pipe 3 for aeration inside the treatment tank 1.

[0026] Optionally, the bottom of the filter ventilation layer 2 is connected to the top of the treatment barrel 1. The filter ventilation layer 2 includes several filter adsorption materials 4, which are evenly distributed on the cross-section of the filter ventilation layer 2.

[0027] The filter adsorption material 4 is vertically arranged and its longitudinal section is wavy; the filter adsorption material 4 is evenly covered with air holes 11, and the positions of the air holes 11 of adjacent filter adsorption materials 4 correspond one-to-one, so that vertical and horizontal airflows are formed in the filter air layer 2.

[0028] Alternatively, the filter adsorption material 4 may be made of silicon carbide, which can adsorb pollutants in the airflow and play a purification role.

[0029] Optionally, the inner diameter of the filter ventilation layer 2 is larger than the inner diameter of the bottom of the gas acceleration and recovery unit, and a ring-shaped sealing plate 12 is provided on the top of the portion of the filter ventilation layer 2 that protrudes from the bottom of the gas acceleration and recovery unit. The inner side of the sealing plate 12 is sealed to the bottom edge of the bottom of the gas acceleration and recovery unit.

[0030] In one specific implementation, each piece of filter adsorption material 4 is rectangular in shape, with both ends fixed to the inner wall of the filter ventilation layer 2. Since the cross-section of the filter ventilation layer 2 is circular, the length of each piece of filter adsorption material 4 is different. In another specific implementation, the filter adsorption material 4 is circular in shape and is concentrically arranged with the filter ventilation layer 2.

[0031] This invention features a filter ventilation layer 2 above the treatment tank 1, with vertically arranged filter adsorption materials 4 forming vertical air channels between adjacent materials. The vent holes 11 of adjacent filter adsorption materials 4 correspond one-to-one, forming horizontal air channels between them. The gas rising from the treatment tank 1 carries solid particles and odors from the wastewater. As it passes through the filter ventilation layer 2, the wavy shape of the filter adsorption materials 4 causes the airflow to deflect at an angle as it passes through the vertical air channels, allowing it to traverse the vent holes 11, thus creating both vertical and horizontal airflow. The rising airflow encountering the sealing plate 12 also flows through the horizontal air channels before merging back into the vertical air channels. This bidirectional mixed airflow within the filter ventilation layer 2 facilitates the adsorption and removal of pollutants from the gas by the filter adsorption materials 4.

[0032] Optionally, a heat collection and conduction layer 13 is provided on the outside of the filter ventilation layer 2, and a diversion fan 14 is provided above the heat collection and conduction layer 13. The air outlet of the diversion fan 14 is connected to the inlet of each heat insulation pipe 10 through a diversion pipe to recover the heat energy of the gas passing through the filter ventilation layer 2 and use it for heat preservation of the treatment tank 1.

[0033] Optionally, several layers of copper sheets 15 are arranged from top to bottom inside the outer shell of the heat collection and conduction layer 13. The copper sheets 15 are circular and horizontally arranged, and the copper sheets 15 surround the outer side of the filter and ventilation layer 2. The inner edge of all the copper sheets 15 is in close contact with the vertical outer surface of the filter and ventilation layer 2. The material of the vertical outer surface of the filter and ventilation layer 2 is preferably copper, which is beneficial to fully conduct the heat of the airflow in the filter and ventilation layer 2 to the heat collection and conduction layer 13.

[0034] Alternatively, the drainage pipe can be directly connected to the aeration pipe 3, allowing hot air to be directly input into the treatment tank 1 through the aeration pipe 3.

[0035] The corrugated design and transverse air channels of the filter adsorption material 4 can prolong the time for airflow to pass through the filter ventilation layer 2, which is beneficial for sufficient heat exchange with the heat collection and conduction layer 13. The air inlet of the induced draft fan 14 introduces outside air, which absorbs heat and is then used for heat preservation or aeration of the heat-insulating pipe 10.

[0036] Optionally, the gas acceleration and recovery unit includes, from bottom to top, a buffer tank 6, a concentration section 7, a confluence section 8, and an outlet tank 9. The inner diameter of the buffer tank 6 is smaller than the inner diameter of the filter ventilation layer 2, which will converge and buffer the airflow passing through the filter ventilation layer 2. The inner diameter of the concentration section 7 gradually decreases from bottom to top. At least one negative pressure pipe 16 is provided on the side of the concentration section 7. The concentration section 7 is connected to the external atmospheric environment through the negative pressure pipe 16 to increase the flow and pressure of the airflow in the concentration section 7.

[0037] The manifold 8 is a vertical circular pipe, and the inner diameter of the outlet groove 9 gradually increases from bottom to top. The top of the outlet groove 9 is sealed and connected to the return pipe 5.

[0038] Alternatively, the buffer tank 6 is cylindrical, and the bottom area of ​​the buffer tank 6 is 30-60% of the top area of ​​the filter ventilation layer 2, so as to buffer and collect the gas flowing through the buffer tank 6 and avoid excessive impact on the inner wall of the concentration section 7.

[0039] Further optionally, the side of the concentration section 7 is provided with a plurality of negative pressure tubes 16, the plurality of negative pressure tubes 16 having the same height and being evenly distributed around the circumference of the concentration section 7.

[0040] The negative pressure pipe 16 is hollow, with one end connected to the inside of the concentration section 7 and the other end connected to the outside atmosphere through a horn opening. The horn opening is set to face downwards. A one-way valve is installed inside the negative pressure pipe 16 near the horn opening, allowing only outside air to enter the concentration section 7 through the negative pressure pipe 16.

[0041] Alternatively, the top of the outlet trough 9 is connected to the return pipe 5 via a T-shaped pipe 17. An aeration fan 18 is installed on the return pipe 5. A shut-off valve is installed at the inlet end of the T-shaped pipe 17 to open or close the T-shaped pipe 17. One end of the T-shaped pipe 17 is connected to the return pipe 5, and the other end is equipped with a one-way valve to connect to the external environment, allowing only outside air to enter the T-shaped pipe 17.

[0042] Further optionally, the height ratio of the concentration section 7 to the manifold is 1:(2-3), and the height ratio of the outlet trough 9 to the manifold is 1:(3-5); the inner diameters of the bottom of the outlet trough 9, the manifold, and the top of the concentration section 7 are equal, and the inner diameter of the top of the outlet trough 9 is not greater than 1 / 3 of the inner diameter of the bottom of the concentration section 7.

[0043] Depending on actual needs, the inlet side of aeration pipe 3 can also be connected to an air supply device (air tank and air pump) to provide supplementary aeration.

[0044] The concentration section 7 compresses and concentrates the rising airflow, thereby creating an acceleration effect. The negative pressure tank is connected to the outside air, and the negative pressure introduces outside air, further increasing the flow rate and pressure of the gas flowing through the concentration section 7.

[0045] In operation, wastewater is treated in treatment tank 1. Aeration pipes 3 are evenly arranged at the bottom of treatment tank 1 to carry out air flotation reaction. Bubbles carrying solid suspended matter in the wastewater float to the surface and enter the filter aeration layer 2. The bubbles break upon contact with the filter adsorption material 4, and the liquid from the bubbles flows back to the treatment tank 1 below through the tiny micropores of the filter adsorption material 4. Pollutants such as ions, particles, and color impurities in the bubble liquid are adsorbed and removed by the filter adsorption material 4. At the same time, the heat energy of the wastewater is fully collected and conducted through the copper sheet 15 of the heat collection and conduction layer 13. The heat energy is then diverted by the exhaust fan 14 to the insulation pipe 10 or the treatment tank 1 for insulation of the treatment tank 1 and heating of the wastewater in cold climates such as winter, improving the efficiency of wastewater air flotation treatment, preventing damage from low temperatures or even freezing, and ensuring the efficient operation of the air flotation treatment device.

[0046] After the bubbles break, the gas continues to rise into the gas acceleration and recovery unit. Under the buffering and acceleration effect of the buffer tank 6 and the concentration section 7, it is further increased in flow and pressure through the negative pressure pipe 16. After being collected and increased in volume through the confluence tank and the outlet tank 9, it is reused through the return pipe 5 to the aeration pipe 3 at the bottom of the treatment tank 1 for aeration under the action of the aeration blower 18.

[0047] The gas overflowing from the top of treatment tank 1 has an odor and is considered polluting. This device can recover and reuse this gas, ensuring its use for aeration while preventing air pollution from leakage. At the same time, this device can also recover and reuse the kinetic energy of the gas and automatically increase pressure and flow without additional energy consumption, effectively reducing the energy consumption of the blower for aeration.

[0048] Optionally, the top of the treatment tank 1 is provided with a trapping screen, which is higher than the liquid surface of the treatment tank 1. The maximum area of ​​the trapping screen can cover the cross-section of the treatment tank 1, and is used to filter pollutants in the rising airflow.

[0049] The inner wall of the treatment tank 1 is provided with a groove corresponding to the height of the interception net. The edge of the interception net is connected to the groove by several sliders, which are evenly distributed along the circumference of the interception net. A support rod is provided at the center of the interception net, and the top of the support rod is connected to the filter adsorption material 4 above to fix the center of the interception net. When the slider moves along the groove, the coverage area of ​​the interception net can be adjusted.

[0050] To reduce the load on the filter ventilation layer 2, a trapping mesh was designed. The mesh is made of ordinary hemp rope and has a spider web pattern, allowing some air bubbles to burst upon contact with it. Liquid is absorbed by the mesh, and a wet mesh more easily adsorbs contaminants. Once the mesh is saturated with moisture, the droplets will drip back into the treatment tank 1. A fully extended mesh would obstruct airflow; therefore, based on the actual odor and airflow conditions within the treatment tank 1 and different trapping requirements, the slider is moved to retract part of the mesh, freeing up space.

Claims

1. A flotation treatment device capable of recovering energy, characterized in that, From bottom to top, it includes a treatment tank, a filter and aeration layer, and a gas acceleration and recovery unit. The bottom of the treatment tank is equipped with an aeration pipe for the flotation treatment of wastewater inside the tank. The filter and aeration layer contains several filter adsorption materials, which filter and remove pollutants in the gas rising from the treatment tank to the filter and aeration layer. The tail end of the gas acceleration and recovery unit is connected to the aeration pipe through a return pipe, so that the gas accelerated by the gas acceleration and recovery unit is reused for aeration of the treatment tank. The gas acceleration and recovery unit includes a lower concentration section and an upper confluence section. The bottom of the concentration section is connected to the filter ventilation layer, and the top of the concentration section is connected to the confluence section. The horizontal cross-section of the concentration section is not smaller than the horizontal cross-section of the confluence section, and the gas is automatically pressurized and increased in flow. The gas acceleration and recovery unit includes, from bottom to top, a buffer tank, a concentration section, a confluence section, and an outlet tank. The inner diameter of the buffer tank is smaller than that of the filter ventilation layer, which will converge and buffer the airflow passing through the filter ventilation layer. The inner diameter of the concentration section gradually decreases from bottom to top. At least one negative pressure pipe is provided on the side of the concentration section. The concentration section is connected to the external atmospheric environment through the negative pressure pipe to increase the flow and pressure of the airflow in the concentration section. The manifold is a vertical circular pipe, and the inner diameter of the outlet groove gradually increases from bottom to top. The top of the outlet groove is sealed and connected to the return pipe.

2. The air flotation treatment device capable of recovering energy according to claim 1, characterized in that, The air flotation treatment device is cylindrical in shape, with the treatment tank, filter air layer, concentration section and confluence section all arranged concentrically. The treatment tank is cylindrical, and several heat-insulating pipes are provided on the outer side of the treatment tank. The heat-insulating pipes are evenly arranged and cover the outer side of the treatment tank, and are used to introduce hot air to keep the treatment tank warm. The outlet of the heat-insulating pipe is connected to the inlet side of the aeration pipe, and the gas after the heat-insulating effect is introduced into the aeration pipe for aeration inside the treatment tank.

3. The air flotation treatment device capable of recovering energy according to claim 1, characterized in that, The bottom of the filter ventilation layer is connected to the top of the treatment barrel. The filter ventilation layer includes several filter adsorption materials, which are evenly distributed on the cross-section of the filter ventilation layer. The filter adsorption material is vertically arranged and its longitudinal section is wavy; the filter adsorption material is evenly and densely covered with air pores, and the positions of the air pores of adjacent filter adsorption materials correspond one-to-one, so that vertical and horizontal airflows are formed in the filter air layer; the filter adsorption material is made of silicon carbide.

4. The air flotation treatment device capable of recovering energy according to claim 2, characterized in that, A heat collection and conduction layer is provided on the outside of the filter ventilation layer, and a diversion fan is provided above the heat collection and conduction layer. The air outlet of the diversion fan is connected to the inlet of each heat insulation pipe through a diversion pipe, so as to recover the heat energy of the gas passing through the filter ventilation layer and use it for heat preservation of the treatment tank.

5. The air flotation treatment device capable of recovering energy according to claim 4, characterized in that, The heat collection and conduction layer has several layers of copper sheets arranged from top to bottom inside its outer shell. The copper sheets are circular and horizontally arranged, and they surround the outer side of the filter and ventilation layer. The inner edges of all the copper sheets are in close contact with the vertical outer surface of the filter and ventilation layer. The vertical outer surface of the filter and ventilation layer is made of copper, which is beneficial for fully conducting the heat of the airflow in the filter and ventilation layer to the heat collection and conduction layer.

6. The air flotation treatment device capable of recovering energy according to claim 1, characterized in that, The negative pressure tube is hollow, with one end connected to the inside of the concentration section and the other end connected to the outside atmosphere through a horn opening. The horn opening is set downwards, and a one-way valve is installed inside the negative pressure tube near the horn opening, allowing only outside air to enter the concentration section through the negative pressure tube.

7. The air flotation treatment device capable of recovering energy according to claim 1, characterized in that, The top of the outlet trough is connected to the return pipe via a T-shaped pipe. An aeration fan is installed on the return pipe. A shut-off valve is installed at the inlet end of the T-shaped pipe to open or close the T-shaped pipe. One end of the T-shaped pipe is connected to the return pipe, and the other end is equipped with a one-way valve to connect to the external environment, allowing only outside air to enter the T-shaped pipe.

8. The air flotation treatment device capable of recovering energy according to claim 1, characterized in that, The height ratio of the concentration section to the manifold is 1:(2-3), and the height ratio of the outlet trough to the manifold is 1:(3-5); the inner diameters of the bottom of the outlet trough, the manifold, and the top of the concentration section are equal, and the inner diameter of the top of the outlet trough is not greater than 1 / 3 of the inner diameter of the bottom of the concentration section.

9. The air flotation treatment device capable of recovering energy according to claim 1, characterized in that, The top of the treatment tank is equipped with a trapping screen, which is higher than the liquid level in the treatment tank. The maximum area of ​​the trapping screen can cover the cross-section of the treatment tank, and is used to filter pollutants in the rising airflow. The inner wall of the treatment tank is provided with a groove corresponding to the height of the interception screen. The edge of the interception screen is connected to the groove by several sliders, which are evenly distributed along the circumference of the interception screen. A support rod is provided at the center of the interception screen, and the top of the support rod is connected to the filter adsorption material above to fix the center of the interception screen. When the slider moves along the groove, the coverage area of ​​the interception screen can be adjusted.

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