A purification device for coffee roasting exhaust gas treatment

Abstract

The utility model discloses a kind of purification devices for coffee baking waste gas treatment, including box, oil fume separating device, high-voltage electric field generating device, first negative pressure generating device, heat exchange device, second negative pressure generating device, electric heating device and catalytic purification device are sequentially equipped with from air inlet to air outlet in box, each module is connected by flow guide pipe, catalytic purification device air outlet end is communicated with heat exchange device.The device removes oil droplet and particulate matter by mechanical centrifugation and electrostatic combination, utilizes two-stage catalytic unit to deeply purify VOCs, and overall purification efficiency reaches more than 99.5%;Adopting countercurrent heat exchange recycles high-temperature gas waste heat after catalysis, preheats air inlet to 120-150 DEG C, reduces electric heating energy consumption by about 30%;Modular layout is compact, maintenance is convenient, operating noise is reduced to below 45 decibels, and it is suitable for coffee baking and other food processing places.

Description

Technical Field

[0001] This utility model relates to the field of waste gas treatment technology, specifically a purification device for treating waste gas from coffee roasting. Background Technology

[0002] The coffee roasting process generates a large amount of complex waste gas, containing not only pollutants such as grease and particulate matter, but also various volatile organic compounds (VOCs). If this waste gas is emitted directly without effective treatment, it will cause serious harm to the environment and human health. Currently, the treatment of such waste gas typically employs single or simple combinations of purification technologies, such as simple mechanical oil fume separation, electrostatic dust removal, or activated carbon adsorption. However, single purification methods often fail to comprehensively and efficiently remove the multiple pollutants in the waste gas, resulting in limited purification efficiency, high energy consumption, and the potential for secondary pollution. In particular, the grease carried in the roasting waste gas can easily cause clogging and performance degradation of processing equipment, and the large amount of heat energy contained in the waste gas is not effectively recovered and utilized, leading to energy waste. Therefore, there is an urgent need to develop an integrated waste gas treatment device that can achieve efficient purification, energy saving, and stable operation. Utility Model Content

[0003] To address the aforementioned challenges, this utility model provides a purification device for treating coffee roasting exhaust gas, comprising a housing. Inside the housing, from the air inlet to the air outlet, are sequentially arranged an oil fume separation device, a high-voltage electric field generating device, a first negative pressure generating device, a heat exchange device, a second negative pressure generating device, an electric heating device, and a catalytic purification device. The functional modules are connected via guide pipes. The air outlet of the catalytic purification device is connected to the heat exchange device.

[0004] Preferably, the oil fume separation device includes a separation shell, a drive motor, and an oil fume separation disc. Both the drive motor and the oil fume separation disc are installed inside the separation shell, and the drive motor drives the oil fume separation disc to rotate at high speed inside the separation shell.

[0005] Preferably, an oil collection box is detachably connected to the bottom of the separator housing.

[0006] Preferably, the high-voltage electric field generating device includes an insulating support, a high-voltage power supply, a discharge electrode, and a dust collecting electrode. The discharge electrode and the dust collecting electrode are arranged parallel to each other on the insulating support. The high-voltage power supply is connected to the discharge electrode through a wire, and the dust collecting electrode is grounded.

[0007] Preferably, the first negative pressure generating device includes a first air duct volute and a first variable frequency fan, the first variable frequency fan is disposed inside the first air duct volute, and the first air duct volute is connected to the air outlet of the high voltage electric field generating device.

[0008] Preferably, the heat exchange device includes a shell and a core, with the core disposed within the shell. The core is formed by stacking multiple layers of interlayered flow channels sequentially along the stacking direction. Adjacent interlayered flow channels are separated by heat transfer baffles to form mutually isolated cold fluid flow channels and hot fluid flow channels. The cold fluid flow channels and hot fluid flow channels are arranged alternately in parallel within the core and adopt a completely counter-current design. The cold fluid flows into all cold fluid flow channels from the cold fluid inlet and flows out to the cold fluid outlet, while the hot fluid flows into all hot fluid flow channels from the hot fluid inlet and flows out to the hot fluid outlet. The cold fluid inlet is connected to the outlet end of the first negative pressure generating device.

[0009] Preferably, the electric heating device includes an electric heating element and aluminum fins, with the aluminum fins fixed to the outer periphery of the electric heating element.

[0010] Preferably, the catalytic purification device includes a primary catalytic unit and a secondary catalytic unit, wherein the primary catalytic unit is located downstream of the electric heating device, and the secondary catalytic unit is located downstream of the primary catalytic unit.

[0011] Preferably, both the primary and secondary catalytic units are filled with supported catalysts, which are selected from one or more combinations of platinum, palladium noble metal catalysts or transition metal oxide catalysts.

[0012] Preferably, the second negative pressure generating device includes a second air duct volute and a second variable frequency fan, the second variable frequency fan being disposed inside the second air duct volute, and the second air duct volute being connected to the cold fluid outlet of the heat exchange device.

[0013] The beneficial effects are as follows: This application utilizes a combination of mechanical centrifugation and high-voltage electrostatic pretreatment to efficiently remove oil droplets and particulate matter, creating favorable conditions for subsequent catalytic reactions; it employs a two-stage catalytic purification unit to deeply oxidize and decompose gaseous pollutants such as VOCs, achieving an overall purification efficiency of over 99.5%. Innovatively, the high-temperature gas after catalytic purification is exchanged counter-currently with the low-temperature waste gas before entering the catalytic unit via a heat exchange device, effectively recovering waste heat and preheating the low-temperature waste gas to 120-150℃, significantly reducing the energy consumption of subsequent electric heating devices by approximately 30%. Modular design and the accompanying flow duct ensure a continuous airflow path without short circuits; the oil fume separation device features a removable oil collection box for easy maintenance; the high-voltage electric field employs an insulated design for safety and reliability; and two independent variable frequency negative pressure generators can flexibly adjust airflow and pressure according to the baking process stages, achieving precise control and energy-saving operation, while enhancing the equipment's adaptability to different operating conditions. The oil fume separation unit employs a vibration-damping design and a special blade structure to effectively reduce vibration and noise during operation, lowering the noise level to below 45 decibels. Optimized layout of each functional module results in a compact structure, effectively reducing the floor space required. Testing showed that the oil content in the coffee roasting exhaust gas was 5g / m³. 3 Initial VOCs concentration 200 mg / m³3 After treatment by this device, the oil content of the discharged gas is ≤0.1g / m³. 3 VOCs exclusion concentration ≤1mg / m³ 3 It is far superior to the relevant national emission standards. The whole device is stable in operation, easy to maintain, energy-saving and environmentally friendly, and is especially suitable for promotion and use in small and medium-sized food processing scenarios such as coffee roasting. Attached Figure Description

[0014] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a cross-sectional view of the present invention; In the picture: 1. Housing; 11. Air inlet; 12. Air outlet; 13. Casters; 2. Oil fume separation device; 21. Separation shell; 211. Oil collection box; 22. Drive motor; 23. Oil fume separation disc; 3. High-voltage electric field generating device; 4. First negative pressure generating device; 41. First air duct casing; 42. First variable frequency fan; 5. Heat exchange device; 51. Shell; 52. Core; 6. Second negative pressure generating device; 61. Second air duct casing; 62. Second variable frequency fan; 7. Electric heating device; 8. Catalytic purification device; 81. Primary catalytic unit; 82. Secondary catalytic unit. Detailed Implementation

[0015] The following drawings will disclose several embodiments of this utility model. For clarity, many practical details will be described in the following description. However, it should be understood that these practical details should not be used to limit this utility model. That is, in some embodiments of this utility model, these practical details are not essential. In addition, for the sake of simplicity, some conventional structures and components will be shown in the drawings in a simple schematic manner.

[0016] It should be noted that all directional indicators in this utility model embodiment, such as up, down, left, right, front, back, etc., are only used to explain the relative positional relationship and movement of the components in a specific posture as shown in the attached figure. If the specific posture changes, the directional indicator will also change accordingly.

[0017] Furthermore, in this utility model, the use of terms such as "first" and "second" is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit the utility model. They are merely used to distinguish components or operations described with the same technical terms and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0018] Example Please see Figure 1 , Figure 1 This is a schematic diagram of the overall structure of this utility model. This embodiment provides a purification device for treating coffee roasting exhaust gas, the core of which lies in achieving the synergistic effect of oil fume separation, electrostatic dust removal, waste heat recovery, and catalytic purification through modular design. The device includes a housing, which is a sealed steel structure shell. Inside the housing, from the air inlet to the air outlet, are sequentially arranged an oil fume separation device, a high-voltage electric field generator, a first negative pressure generator, a heat exchange device, a second negative pressure generator, an electric heating device, and a catalytic purification device. The functional modules are connected by guide pipes to ensure a continuous airflow path without short circuits. The outlet of the catalytic purification device is connected to the heat exchange device, used to exchange heat between the high-temperature gas after catalytic purification and the low-temperature exhaust gas before entering the catalytic purification device, recovering waste heat and discharging it from the outlet of the housing. To reduce the space occupied by the device, the layout of the above functional modules is optimized, such as... Figure 1 As shown, viewed from the front of the device, from left to right, the bottom of the box is equipped with an oil fume separation device, a high-voltage electric field generating device, and a first negative pressure generating device. The heat exchange device is arranged above the first negative pressure generating device, and the second negative pressure generating device is arranged above the heat exchange device. The electric heating device and the catalytic purification device are both arranged to the left of the heat exchange device, and the catalytic purification device is located below the electric heating device. Each functional module is electrically connected to the control device, and the control device uniformly controls the coordinated operation of each functional module.

[0019] Please see Figure 2 , Figure 2This is a cross-sectional view of the present invention. The oil fume separation device includes a separation shell, a drive motor, and an oil fume separation disc. The drive motor is coaxially connected to the oil fume separation disc via a coupling. Both are installed inside the separation shell. The drive motor drives the oil fume separation disc to rotate at high speed inside the separation shell, so as to separate oil droplets and particulate matter in the exhaust gas through centrifugal force. A shock-absorbing pad is provided between the drive motor and the oil fume separation disc. The shock-absorbing pad is made of silicone or rubber and can effectively reduce vibration and noise. The oil fume separation disc includes oil guide blades radially distributed around its central axis. At least a portion of the oil guide blades have an asymmetrical curved structure. The bending direction of the asymmetrical curved structure alternates along the rotation tangent to increase the interception area of ​​the oil fume airflow while reducing vibration and noise caused by airflow turbulence during rotation. The curvature of the curved structure surface changes continuously to guide the oil droplets to flow along a specific path and be thrown towards the inner wall of the separation shell under the action of centrifugal force and then flow into the oil collection box, which greatly improves the separation efficiency. The bottom of the separator housing is detachably connected to an oil collection box via a plug-in structure for periodic cleaning of the separated grease. In this embodiment, insert strips are provided on both sides of the oil collection box, and slots adapted to the insert strips are provided at the bottom of the separator housing. A liquid level sensor is installed inside the oil collection box to monitor the oil level. The liquid level sensor is electrically connected to an alarm, which is located on the outer wall of the housing. The liquid level sensor can trigger the alarm when the oil is full to prevent overflow.

[0020] See also Figure 2 The high-voltage electric field generator is used to apply an electrostatic field to the exhaust gas after oil fume separation, capturing micron-sized oil mist particles. The generator includes an insulating support, a high-voltage power supply, a discharge electrode, and a dust-collecting electrode. The discharge electrode and dust-collecting electrode are arranged parallel to each other on the insulating support to form an electrostatic field region. The high-voltage power supply is connected to the discharge electrode via a wire, and the dust-collecting electrode is grounded. The electric field strength is 3-5 kV / cm. When the exhaust gas after oil fume separation flows through the electrostatic field region, the micron-sized oil mist particles become charged under corona discharge and migrate towards the dust-collecting electrode under the drive of the electric field force, where they are captured, thus achieving efficient purification. To prevent short circuits in the electric field, the insulating support can be made of ceramic material.

[0021] See also Figure 2 The first negative pressure generating device includes a first air duct volute and a first variable frequency fan. The first variable frequency fan is located inside the first air duct volute, and the first air duct volute is connected to the air outlet of the high voltage electric field generating device.

[0022] See also Figure 2The heat exchange device includes a shell and a core, with the core housed within the shell and made of aluminum-magnesium alloy. The core is composed of multiple layers of sandwiched flow channels stacked sequentially along the stacking direction. Adjacent sandwiched flow channels are separated by heat transfer baffles, forming isolated cold fluid and hot fluid flow channels. These cold and hot fluid flow channels are arranged alternately in parallel within the core, employing a completely counter-current design. Cold fluid flows into all cold fluid channels from the cold fluid inlet and exits through the cold fluid outlet, while hot fluid flows into all hot fluid channels from the hot fluid inlet and exits through the hot fluid outlet, achieving highly efficient counter-current heat transfer between the cold and hot fluids. The cold fluid inlet is connected to the outlet of the first negative pressure generator via a guide pipe, and the hot fluid outlet is connected to the outlet of the housing via a guide pipe. This counter-current design increases the heat exchange efficiency to 85%. After heat exchange, the low-temperature exhaust gas can be heated to 120-150℃, and then further heated by an electric heating device to the catalyst's required temperature of over 200℃, reducing electric heating energy consumption by 30%.

[0023] The electric heating device includes an electric heating element and aluminum fins. The aluminum fins are fixed to the outer periphery of the electric heating element to increase the heat exchange area. The heating rate reaches 10℃ / min, which can quickly heat the exhaust gas to the temperature required for the catalytic reaction.

[0024] See also Figure 2 The catalytic purification device includes a primary catalytic unit and a secondary catalytic unit. The primary catalytic unit is located downstream of the electric heating device, and the secondary catalytic unit is located downstream of the primary catalytic unit. The primary catalytic unit is used to oxidize and decompose most volatile organic compounds, while the secondary catalytic unit is used for deep purification of residual pollutants. Both the primary and secondary catalytic units include a support, which can be made of metals such as Fe-Cr-Al alloys or ceramic materials. Fe-Cr-Al alloys have good thermal conductivity and high mechanical strength, making them suitable for rapid ignition scenarios, while ceramics have advantages such as high temperature resistance and good chemical stability. The support is filled with a supported catalyst, which is selected from one or more combinations of platinum, palladium noble metal catalysts, or transition metal oxide catalysts. In this embodiment, the primary catalytic unit is filled with a platinum-palladium bimetallic catalyst, and the secondary catalytic unit is filled with a transition metal oxide catalyst, such as manganese-based or cobalt-based oxides. The outlet of the catalytic purification device is connected to the hot fluid inlet of a heat exchange device. The purification efficiency can be increased to over 99.5% through the two-stage catalytic units.

[0025] See also Figure 2The second negative pressure generating device includes a second air duct casing and a second variable frequency fan. The second variable frequency fan is located inside the second air duct casing, and the inlet end of the second air duct casing is connected to the cold fluid outlet of the heat exchange device through a guide pipe. The first and second variable frequency fans are each controlled by an independent variable frequency controller, which can automatically match the air volume and energy consumption according to the baking process stage to achieve energy-saving operation. For example, during the heating period, the first variable frequency fan adjusts the air volume to 80%, and the second variable frequency fan adjusts the air volume to 50%; during the constant temperature period, the first variable frequency fan adjusts the air volume to 60%, and the second variable frequency fan adjusts the air volume to 70%. Compared with fixed frequency operation, energy consumption can be reduced by 25%.

[0026] See also Figure 1 and Figure 2 For easy movement, casters can also be installed at the bottom of the box.

[0027] Airflow path during use: Low-temperature exhaust gas enters the oil fume separator from the air inlet of the box → is dusted by the high-voltage electric field generator → the flow rate is adjusted by the first negative pressure generator → after entering the heat exchange device, it exchanges heat with the high-temperature gas after catalytic purification in a countercurrent flow → the flow rate is adjusted by the second negative pressure generator → the temperature is raised by the electric heating device → purification is completed in the catalytic purification device → and finally discharged from the air outlet of the box.

[0028] In summary, this application utilizes a combined mechanical centrifugation and high-voltage electrostatic pretreatment process to efficiently remove oil droplets and particulate matter, creating favorable conditions for subsequent catalytic reactions. A two-stage catalytic purification unit is employed to deeply oxidize and decompose gaseous pollutants such as VOCs, achieving an overall purification efficiency of over 99.5%. Innovatively, the high-temperature gas after catalytic purification undergoes countercurrent heat exchange with the low-temperature waste gas before entering the catalytic unit via a heat exchange device, effectively recovering waste heat and preheating the low-temperature waste gas to 120-150℃. This significantly reduces the energy consumption of the subsequent electric heating device, decreasing electricity consumption by approximately 30%. Modular design and the accompanying flow duct ensure a continuous airflow path without short circuits. The oil fume separation device features a removable oil collection box for easy maintenance. The high-voltage electric field employs an insulated design for safety and reliability. Two independent variable frequency negative pressure generators can flexibly adjust airflow and pressure according to the baking process stages, achieving precise control and energy-saving operation, while enhancing the equipment's adaptability to different operating conditions. The oil fume separation unit employs a vibration-damping design and a special blade structure to effectively reduce vibration and noise during operation, lowering the noise level to below 45 decibels. Optimized layout of each functional module results in a compact structure, effectively reducing the floor space required. Testing showed that the oil content in the coffee roasting exhaust gas was 5g / m³. 3 Initial VOCs concentration 200 mg / m³ 3 After treatment by this device, the oil content of the discharged gas is ≤0.1g / m³. 3 VOCs exclusion concentration ≤1mg / m³ 3It is far superior to the relevant national emission standards. The whole device is stable in operation, easy to maintain, energy-saving and environmentally friendly, and is especially suitable for promotion and use in small and medium-sized food processing scenarios such as coffee roasting.

[0029] The above are merely embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this utility model should be included within the scope of the claims of this utility model.

Claims

1. A purification device for coffee roasting exhaust gas treatment, characterized by, The device includes a housing, and inside the housing, from the air inlet to the air outlet, are sequentially arranged an oil fume separation device, a high-voltage electric field generating device, a first negative pressure generating device, a heat exchange device, a second negative pressure generating device, an electric heating device, and a catalytic purification device. The functional modules are connected to each other through a guide pipe. The air outlet of the catalytic purification device is connected to the heat exchange device.

2. The purification device for coffee roasting exhaust gas treatment according to claim 1, characterized in that, The oil fume separation device includes a separation shell, a drive motor, and an oil fume separation disc. The drive motor and the oil fume separation disc are both installed inside the separation shell, and the drive motor drives the oil fume separation disc to rotate at high speed inside the separation shell.

3. The purification device for treating coffee roasting exhaust gas according to claim 2, characterized in that, An oil collection box is detachably connected to the bottom of the separation shell.

4. The purification device for treating coffee roasting exhaust gas according to claim 1, characterized in that, The high-voltage electric field generating device includes an insulating support, a high-voltage power supply, a discharge electrode, and a dust collecting electrode. The discharge electrode and the dust collecting electrode are arranged parallel to each other on the insulating support. The high-voltage power supply is connected to the discharge electrode through a wire, and the dust collecting electrode is grounded.

5. The purification device for treating coffee roasting exhaust gas according to claim 1, characterized in that, The first negative pressure generating device includes a first air duct volute and a first variable frequency fan. The first variable frequency fan is located inside the first air duct volute, and the first air duct volute is connected to the air outlet of the high voltage electric field generating device.

6. The purification device for treating coffee roasting exhaust gas according to claim 1, characterized in that, The heat exchange device includes a shell and a core, with the core disposed within the shell. The core is formed by stacking multiple layers of interlayered flow channels sequentially along the stacking direction. Adjacent interlayered flow channels are separated by heat transfer baffles, forming mutually isolated cold fluid flow channels and hot fluid flow channels. The cold fluid flow channels and hot fluid flow channels are arranged alternately in parallel within the core and employ a completely counter-current design. The cold fluid flows into all cold fluid flow channels from the cold fluid inlet and flows out to the cold fluid outlet, while the hot fluid flows into all hot fluid flow channels from the hot fluid inlet and flows out to the hot fluid outlet. The cold fluid inlet is connected to the outlet end of the first negative pressure generating device.

7. The purification device for treating coffee roasting exhaust gas according to claim 1, characterized in that, The electric heating device includes an electric heating element and aluminum fins, with the aluminum fins fixed to the outer periphery of the electric heating element.

8. The purification device for treating coffee roasting exhaust gas according to claim 1, characterized in that, The catalytic purification device includes a primary catalytic unit and a secondary catalytic unit. The primary catalytic unit is located downstream of the electric heating device, and the secondary catalytic unit is located downstream of the primary catalytic unit.

9. The purification device for treating coffee roasting exhaust gas according to claim 8, characterized in that, Both the primary and secondary catalytic units are filled with supported catalysts, which are selected from one or more combinations of platinum, palladium noble metal catalysts, or transition metal oxide catalysts.

10. The purification device for treating coffee roasting exhaust gas according to claim 1, characterized in that, The second negative pressure generating device includes a second air duct casing and a second variable frequency fan. The second variable frequency fan is disposed inside the second air duct casing, and the second air duct casing is connected to the cold fluid outlet of the heat exchange device.

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