A process for treating waste gas and waste liquid tank residues of a DMF recovery device

Abstract

The application discloses a kind of DMF recovery device exhaust waste liquid kettle residual treatment process, it is related to DMF recovery technical field, the process first converts dimethylamine concentrated solution into gaseous dimethylamine and dimethylamine concentrated solution, then by exhaust gas incinerator to system tail gas and gaseous dimethylamine are incinerated, by waste liquid incinerator to rectifying kettle residual and dimethylamine concentrated solution are incinerated, high-temperature flue gas after processing is recycled by waste heat boiler and air preheater heat, simultaneously by quenching tower to flue gas is desulfurized and denitrified, to make flue gas discharge up to standard, compared with prior art, DMF recovery device generated system tail gas, dimethylamine concentrated solution, rectifying kettle residual can be handled by incineration, process is simple, effectively reduce production cost, simultaneously, high-temperature flue gas generated by incineration, under the action of waste heat boiler and air preheater, heat recycling is carried out, energy consumption is reduced, the purpose of energy saving and emission reduction is achieved.

Description

Technical Field

[0001] This invention relates to the field of DMF recovery technology, specifically a process for treating waste gas, waste liquid, and residue in a DMF recovery device. Background Technology

[0002] DMF recycling facilities in the synthetic leather industry generate three types of waste:

[0003] Distillation kettle residue: The main components are wood powder, calcium powder and other solids, DMF and organosilicon, each accounting for one-third.

[0004] Dimethylamine concentrate: a product of DMF hydrolysis within the system, containing 10% dimethylamine and the remainder being water.

[0005] System exhaust gas: The exhaust gas discharged by the vacuum pump mainly consists of small amounts of dimethylamine, carbon monoxide, water vapor, and air.

[0006] The main methods for treating the three types of waste are as follows:

[0007] Distillation kettle residue: As hazardous waste, it needs to be handled by qualified companies, which requires the tanneries to incur certain financial costs.

[0008] Dimethylamine concentrate: Some manufacturers treat it as hazardous waste and entrust it to qualified companies for disposal, which requires the tanneries to spend a certain amount of money; other manufacturers use sulfuric acid for neutralization, which increases the treatment process, generates odor during operation, and more importantly, increases the treatment cost.

[0009] System exhaust gas: Absorbed using an exhaust gas absorption tower, with the absorbent returned to the recovery unit. This increases treatment costs.

[0010] In summary, all three current waste treatment processes increase the operating costs of DMF recycling units.

[0011] Some manufacturers have added separate incinerators to incinerate dimethylamine concentrate, but they have not recovered the heat from the high-temperature flue gas, nor have they treated the flue gas. Moreover, they consume a large amount of natural gas for combustion, resulting in higher operating costs, and this is only a temporary solution.

[0012] Most existing waste liquid incinerators burn the oxidizer and waste liquid separately, which cannot fully mix the waste liquid and oxidizer, resulting in low waste liquid incineration efficiency. At the same time, the air supply equipment of most existing waste liquid incinerators blows air directly instead of blowing it from bottom to top, and the ash from combustion easily falls into the air supply pipe, which is inconvenient for ash disposal, affects air supply efficiency, and is inconvenient for users.

[0013] To address the aforementioned issues, an improved process for treating waste gas, waste liquid, and residue in the reactor of a DMF recovery device is now designed. Summary of the Invention

[0014] The purpose of this invention is to provide a process for treating waste gas, waste liquid, and residue in a DMF recovery device, so as to solve the problems mentioned in the background art.

[0015] To achieve the above objectives, the present invention provides the following technical solution:

[0016] A process for treating waste gas, waste liquid, and residue from a DMF recovery device includes the following steps:

[0017] Step 1: DMF is recovered through a DMF recovery device, generating three types of waste: system tail gas, dimethylamine concentrate, and distillation kettle residue.

[0018] Step 2: The dimethylamine concentrate from Step 1 is fed into a stripping tower for stripping to produce gaseous dimethylamine, which improves the heat recovery efficiency.

[0019] Step 3: Mix the gaseous dimethylamine from Step 2 with the system exhaust gas from Step 1, and then add them together into the waste gas incinerator for incineration, while generating high-temperature flue gas.

[0020] Step 4: Mix the dimethylamine concentrate from Step 1 with the distillation vessel residue from Step 1, and then add them together to the waste liquid incinerator for incineration, while generating high-temperature flue gas.

[0021] Step 5: The high-temperature flue gas generated in Step 3 and Step 4 is transported together to the waste heat boiler, which will generate steam to recover the heat energy from combustion.

[0022] Step Six: The by-product steam from Step Five is transported to the DMF recovery unit to supplement the heat of the DMF recovery unit.

[0023] Step 7: The steam from Step 5 is transported to the quench tower for desulfurization and denitrification, while preventing the generation of dioxins and discharging clean flue gas.

[0024] Step 8: The clean flue gas discharged in Step 7 is transported to the air preheater. The air preheater preheats the combustion air of the waste gas incinerator and the waste liquid incinerator to further recover heat. Finally, the air preheater discharges the flue gas through the chimney.

[0025] At low loads, only the waste liquid incinerator is used; at high loads, both the waste gas incinerator and the waste liquid incinerator are used simultaneously to ensure that the load can be adjusted from 30% to 110%.

[0026] As a further aspect of the present invention: the waste gas incinerator in step three is a horizontal incinerator.

[0027] As a further aspect of the present invention: the waste gas incinerator in step three is equipped with a high-pressure air supply system to supplement the oxygen required for waste combustion, and the furnace temperature can be controlled by adjusting the amount of air in the incinerator.

[0028] A waste liquid incinerator includes an incinerator body, a mixing and spraying mechanism, an air supply mechanism, and a pressure relief mechanism. A bracket is installed at the lower end of the incinerator body, and a support cylinder is vertically installed at the center of the bottom of the incinerator body. A flame jet head for incinerating the waste liquid is installed on the inner wall of the incinerator body. An exhaust pipe for discharging incinerated gases is installed at the upper end of the incinerator body. A first electrically controlled valve for controlling the opening and closing of the exhaust pipe is installed on the side wall of the exhaust pipe. A gas pressure sensor for detecting the internal gas pressure of the incinerator body is installed at the top of the incinerator body. A controller for receiving signals from the gas pressure sensor and controlling the first electrically controlled valve is installed at the upper end of the incinerator body.

[0029] The mixing and spraying mechanism is located inside the support cylinder and is used to spray the waste liquid and combustion aid together into the interior of the incinerator body, so that the waste liquid and combustion aid are fully mixed and the efficiency of waste liquid incineration is improved.

[0030] The air supply mechanism is located at the bottom of the incinerator body and is used to transport external air into the interior of the incinerator body to provide sufficient oxygen and ensure the complete combustion of waste liquid.

[0031] The pressure relief mechanism is located at the upper end of the incinerator body and is used to relieve pressure inside the incinerator body to prevent excessive internal pressure from affecting the safety of waste liquid treatment.

[0032] As a further embodiment of the present invention: the mixing spraying mechanism includes a waste liquid conveying cylinder, which is rotatably connected to the inner wall of a support cylinder. A combustion-supporting agent conveying cylinder is vertically installed at the top center of the waste liquid conveying cylinder. Both the waste liquid conveying cylinder and the combustion-supporting agent conveying cylinder are rotatably connected to a sealing cap at their lower ends. A support rod is installed on the side wall of the sealing cap, with the end of the support rod away from the sealing cap installed on the side wall of the support frame. A combustion-supporting agent inlet pipe for conveying combustion-supporting agent into the combustion-supporting agent conveying cylinder is installed on the sealing cap inside the combustion-supporting agent conveying cylinder. A waste liquid inlet pipe for conveying waste liquid into the waste liquid conveying cylinder is installed on the sealing cover between the combustion aid conveying cylinder and the waste liquid conveying cylinder. A combustion aid spraying pipe for spraying combustion aid into the incinerator body is installed on the side wall of the combustion aid conveying cylinder. The end of the combustion aid spraying pipe away from the combustion aid conveying cylinder passes through the waste liquid conveying cylinder and is horizontally installed inside the incinerator body. A waste liquid spraying pipe for spraying waste liquid into the incinerator body is horizontally installed on the side wall of the waste liquid conveying cylinder. A drive assembly for driving the waste liquid conveying cylinder to rotate is installed inside the bracket.

[0033] As a further embodiment of the present invention: the drive assembly includes a gear ring, which is installed on the side wall of the waste liquid conveying cylinder inside the bracket, and a motor is installed at the bottom of the bracket. A gear is installed at the output end of the motor, and the gear meshes with the gear ring.

[0034] As a further embodiment of the present invention: the air supply mechanism includes a plurality of blowers, which are arranged in a circular array on the lower side wall of the incinerator body. A backflow frame corresponding to each blower is installed at the bottom of the incinerator body. An L-shaped air inlet pipe is installed at the output end of each blower. The end of the L-shaped air inlet pipe away from the blower passes through the side wall of the incinerator body and is positioned above the backflow frame. The output end of the L-shaped air inlet pipe is vertically downward.

[0035] As a further embodiment of the present invention: the pressure relief mechanism includes a pressure relief pipe, which is installed at the upper end of the incinerator body, a pressure buffer storage tank is installed at the output end of the pressure relief pipe, and a second electrically controlled valve for controlling the opening and closing of the pressure relief pipe is installed on the side wall of the pressure relief pipe.

[0036] As a further aspect of the present invention: the input end of the blower is equipped with a filter cover for filtering air.

[0037] As a further aspect of the present invention: the inner wall of the incinerator body is equipped with corundum refractory material and thermal insulation material.

[0038] Compared with the prior art, the beneficial effects of the present invention are:

[0039] Compared with existing technologies, the present invention can treat the system tail gas, dimethylamine concentrate, and distillation kettle residue generated by the DMF recovery device by incineration, which is simple and effectively reduces production costs.

[0040] Stripping the dimethylamine concentrate using a stripping tower improves heat recovery efficiency.

[0041] Meanwhile, the high-temperature flue gas generated by combustion is recycled and utilized by the waste heat boiler and air preheater, reducing energy consumption and achieving the goal of energy conservation and emission reduction.

[0042] At low loads, only the waste liquid incinerator is used, while at high loads, both the waste gas incinerator and the waste liquid incinerator are used simultaneously, ensuring that the load can be adjusted from 30% to 110%, providing great operational flexibility to meet the different production conditions of the upstream DMF recovery unit.

[0043] Compared with existing technologies, the waste liquid spray pipe and the combustion aid spray pipe are rotated by a motor, so that the waste liquid and the combustion aid are mixed inside the incinerator body, which facilitates the incineration of the waste liquid, effectively improves the incineration efficiency of the waste liquid, and is convenient for users.

[0044] Compared with existing technologies, the output end of the L-shaped air inlet pipe is vertically downward, and the air is reflected and redirected by the backflow frame to prevent the incineration ash from falling into the interior of the L-shaped air inlet pipe. At the same time, the ash can be made to fly around and mix with the combustion aid again, so as to fully incinerate the waste liquid and improve the efficiency of waste liquid incineration.

[0045] Compared with existing technologies, by transporting the flue gas inside the incinerator body to the inside of the pressure buffer storage tank, the pressure of the incinerator body is depressurized, thereby ensuring the safety of waste liquid treatment. At the same time, the flue gas is stored in the pressure buffer storage tank to prevent flue gas leakage and protect the environment. Attached Figure Description

[0046] Figure 1 This is a flowchart of the present invention.

[0047] Figure 2 This is a three-dimensional structural schematic diagram of the waste liquid incinerator in this invention.

[0048] Figure 3 This is a schematic diagram of the waste liquid incinerator in this invention.

[0049] Figure 4 This is a schematic diagram of the combustion-supporting agent delivery cylinder in this invention.

[0050] Figure 5 This is a schematic diagram of the air supply mechanism in this invention.

[0051] The components include: 1. Incinerator body; 2. First electrically controlled valve; 3. Exhaust pipe; 4. Controller; 5. Second electrically controlled valve; 6. Pressure relief pipe; 7. Pressure buffer storage tank; 8. Support; 9. Sealing cover; 10. Motor; 11. Blower; 12. Gear; 13. Backflush frame; 14. L-shaped air inlet pipe; 15. Flame nozzle; 16. Gas pressure sensor; 17. Waste liquid spray pipe; 18. Combustion accelerator spray pipe; 19. Waste liquid conveying cylinder; 20. Support cylinder; 21. Gear ring; 22. Support rod; 23. Waste liquid input pipe; 24. Combustion accelerator input pipe; 25. Combustion accelerator conveying cylinder. Detailed Implementation

[0052] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0053] Please see Figure 1 In this embodiment of the invention, a process for treating waste gas and waste liquid residue in a DMF recovery device includes the following steps:

[0054] Step 1: DMF is recovered through a DMF recovery device, generating three types of waste: system tail gas, dimethylamine concentrate, and distillation kettle residue.

[0055] Step 2: The dimethylamine concentrate from Step 1 is fed into a stripping tower for stripping to produce gaseous dimethylamine, which improves the heat recovery efficiency.

[0056] Step 3: Mix the gaseous dimethylamine from Step 2 with the system exhaust gas from Step 1, and then add them together into the waste gas incinerator for incineration, while generating high-temperature flue gas.

[0057] Step 4: Mix the dimethylamine concentrate from Step 1 with the distillation vessel residue from Step 1, and then add them together to the waste liquid incinerator for incineration, while generating high-temperature flue gas.

[0058] Step 5: The high-temperature flue gas generated in Step 3 and Step 4 is transported together to the waste heat boiler, which will generate steam to recover the heat energy from combustion.

[0059] Step Six: The by-product steam from Step Five is transported to the DMF recovery unit to supplement the heat of the DMF recovery unit.

[0060] Step 7: The steam from Step 5 is transported to the quench tower for desulfurization and denitrification, while preventing the generation of dioxins and discharging clean flue gas.

[0061] Step 8: The clean flue gas discharged in Step 7 is transported to the air preheater. The air preheater preheats the combustion air of the waste gas incinerator and the waste liquid incinerator to further recover heat. Finally, the air preheater discharges the flue gas through the chimney.

[0062] At 30% total load, the corresponding flue gas volume is 14600*0.3=4380nm3 / h, with the waste liquid furnace operating alone.

[0063] The waste liquid furnace operates at a load of 4380 / 5800=76%, which can maintain normal combustion. By controlling the boiler heat transfer area, the boiler outlet temperature is maintained at 500℃. The system does not increase gas consumption and meets the specifications, only maintaining a permanent flame.

[0064] At 60% total load, the corresponding flue gas volume is 14600*0.6=8760nm3 / h.

[0065] Option 1: Operate a waste liquid furnace and a waste gas furnace;

[0066] The waste liquid furnace is operating at a load of 4380 / 5800=76%, indicating normal combustion.

[0067] The operating load of the waste gas furnace is (8760-4380) / 8800=4380 / 8800=49.8%, which means it can burn normally. The boiler outlet temperature can be maintained at 280℃ by controlling the actual heat transfer area of ​​the boiler.

[0068] Option 2: Operate the waste liquid furnace;

[0069] The waste liquid furnace is operating at 6380 / 5800 = 110% load, indicating normal combustion.

[0070] The dimethylamine waste gas is temporarily stored, and a production plan is developed. When the waste gas furnace is started later, the incineration volume is increased to ensure full-load, high-efficiency operation. The system does not require additional fuel consumption; only a continuous flame is maintained.

[0071] At 70% total load, the corresponding flue gas volume is 14600*0.7=10220nm3 / h, operating the waste liquid furnace and the waste gas furnace;

[0072] The waste liquid furnace flue gas volume is 5800 nm3 / h, operating at 100% load, and undergoing normal combustion;

[0073] The waste gas combustion rate is (10220-5800) / 8800=4420 / 8800=50.2%, indicating normal combustion. The boiler outlet temperature can be maintained at 280℃ by controlling the boiler's heat transfer area. The system requires no additional fuel consumption, only a continuous flame.

[0074] At 100% total load, the total flue gas volume is: 5800 nm3 / h for waste liquid furnace + 8800 nm3 / h for waste gas furnace; of which the waste liquid furnace accounts for 5800 / 14600=39.7%; the system does not consume fuel and only maintains a continuous flame.

[0075] The waste gas incinerator in step three is a horizontal incinerator.

[0076] The waste liquid incinerator in step four is a dual-furnace vertical incinerator.

[0077] Both the waste gas incinerator and the waste liquid incinerator in steps three and four are equipped with high-pressure air supply systems to supplement the oxygen required for waste combustion, and the furnace temperature can be controlled by adjusting the amount of air in the incinerator.

[0078] The waste liquid incinerator in step four is equipped with an emergency discharge port, which can be automatically opened to relieve pressure in an emergency.

[0079] Compared with existing technologies, the system tail gas, dimethylamine concentrate, and distillation kettle residue generated by the DMF recovery unit can all be treated by incineration, which is simple and effectively reduces production costs.

[0080] Meanwhile, the high-temperature flue gas generated by combustion is recycled and utilized by the waste heat boiler and air preheater, reducing energy consumption and achieving the goal of energy conservation and emission reduction.

[0081] The production load can be adjusted between 30% and 110%, providing great operational flexibility to meet different production conditions of the upstream DMF recovery unit.

[0082] Please see Figures 2-5 A waste liquid incinerator includes an incinerator body 1, a mixing and spraying mechanism, an air supply mechanism, and a pressure relief mechanism. A bracket 8 is installed at the lower end of the incinerator body 1, and a support cylinder 20 is vertically installed at the center of the bottom of the incinerator body 1. A flame jet head 15 for incinerating waste liquid is installed on the inner wall of the incinerator body 1. An exhaust pipe 3 for discharging incinerated gas is installed at the upper end of the incinerator body 1. A first electrically controlled valve 2 for controlling the opening and closing of the exhaust pipe 3 is installed on the side wall of the exhaust pipe 3. A gas pressure sensor 16 for detecting the internal gas pressure of the incinerator body 1 is installed at the top of the incinerator body 1. A controller 4 for receiving the signal from the gas pressure sensor 16 and controlling the first electrically controlled valve 2 is installed at the upper end of the incinerator body 1.

[0083] The mixing spraying mechanism is located inside the support cylinder 20 and is used to spray the waste liquid and combustion aid together into the interior of the incinerator body 1, so that the waste liquid and combustion aid are fully mixed and the efficiency of waste liquid incineration is improved.

[0084] The air supply mechanism is located at the bottom of the incinerator body 1 and is used to transport external air into the interior of the incinerator body 1 to provide sufficient oxygen to the interior of the incinerator body 1 and ensure the complete combustion of waste liquid.

[0085] The pressure relief mechanism is located at the upper end of the incinerator body 1 and is used to relieve pressure inside the incinerator body 1 to prevent excessive internal pressure from affecting the safety of waste liquid treatment.

[0086] The mixing spraying mechanism includes a waste liquid conveying cylinder 19, which is rotatably connected to the inner wall of a support cylinder 20. A combustion-supporting agent conveying cylinder 25 is vertically installed at the top center of the waste liquid conveying cylinder 19. Both the waste liquid conveying cylinder 19 and the combustion-supporting agent conveying cylinder 25 are rotatably connected to a sealing cap 9 at their lower ends. A support rod 22 is installed on the side wall of the sealing cap 9, with one end of the support rod 22 away from the sealing cap 9 installed on the side wall of a bracket 8. A combustion-supporting agent inlet pipe 24 for conveying combustion-supporting agent into the combustion-supporting agent conveying cylinder 25 is installed on the sealing cap 9 inside the combustion-supporting agent conveying cylinder 25. A waste liquid inlet pipe 23 for conveying waste liquid into the waste liquid conveying cylinder 19 is installed on the sealing cover 9 between the 25 and the waste liquid conveying cylinder 19. An accelerator spraying pipe 18 for spraying accelerator into the incinerator body 1 is installed on the side wall of the accelerator conveying cylinder 25. The end of the accelerator spraying pipe 18 away from the accelerator conveying cylinder 25 passes through the waste liquid conveying cylinder 19 and is horizontally arranged inside the incinerator body 1. A waste liquid spraying pipe 17 for spraying waste liquid into the incinerator body 1 is horizontally installed on the side wall of the waste liquid conveying cylinder 19. A drive assembly for driving the waste liquid conveying cylinder 19 to rotate is provided inside the bracket 8.

[0087] The drive assembly includes a gear ring 21, which is installed on the side wall of the waste liquid conveying cylinder 19 inside the bracket 8. A motor 10 is installed at the bottom of the bracket 8, and a gear 12 is installed at the output end of the motor 10. The gear 12 meshes with the gear ring 21.

[0088] During operation, the motor 10 is started, and its output drives the gear 12 to rotate. The gear 12 drives the gear ring 21 to rotate, which in turn drives the waste liquid conveying cylinder 19 to rotate. The waste liquid conveying cylinder 19 then drives the waste liquid spraying pipe 17 and the combustion aid spraying pipe 18 to rotate. Simultaneously, waste liquid is conveyed into the waste liquid conveying cylinder 19 through the waste liquid input pipe 23. The waste liquid passes through the waste liquid conveying cylinder 19 and enters the waste liquid spraying pipe 17, which sprays the waste liquid onto the inside of the incinerator body 1. Combustion aid is conveyed into the combustion aid conveying cylinder 25 through the combustion aid input pipe 24. The combustion aid passes through the combustion aid conveying cylinder 25 and enters the combustion aid system. Inside the fuel spray pipe 18, the fuel spray pipe 18 sprays the fuel into the interior of the incinerator body 1, thereby mixing the waste liquid and the fuel. Then, the flame nozzle 15 is activated, and the waste liquid is burned under the action of the fuel. As the pressure inside the incinerator body 1 increases, the gas pressure sensor 16 sends the detected gas pressure signal to the controller 4. The controller 4 judges the gas pressure. When the gas pressure reaches the set value inside the controller 4, the controller 4 sends a signal to the first electric valve 2. The first electric valve 2 opens the exhaust pipe 3, thereby allowing the exhaust pipe 3 to output the high-temperature flue gas inside the incinerator body 1.

[0089] Compared with the prior art, the waste liquid spray pipe 17 and the combustion aid spray pipe 18 are rotated by the motor 10, so that the waste liquid and the combustion aid are mixed inside the incinerator body 1, which facilitates the incineration of the waste liquid, effectively improves the incineration efficiency of the waste liquid, and is convenient for users.

[0090] The air supply mechanism includes a plurality of blowers 11, which are arranged in a circular array on the lower side wall of the incinerator body 1. A backflow frame 13 corresponding to each blower 11 is installed at the bottom of the incinerator body 1. An L-shaped air inlet pipe 14 is installed at the output end of each blower 11. The end of the L-shaped air inlet pipe 14 away from the blower 11 passes through the side wall of the incinerator body 1 and is positioned above the backflow frame 13. The output end of the L-shaped air inlet pipe 14 is vertically downward.

[0091] When in use, start the blower 11. The output end of the blower 11 blows air to the backflow frame 13 through the L-shaped air inlet pipe 14. The backflow frame 13 reflects the air upward, thus making the air blow upward.

[0092] Compared with existing technologies, the output end of the L-shaped air inlet pipe 14 is vertically downward, and the air is reflected and redirected by the backflow frame 13 to prevent the burning ash from falling into the interior of the L-shaped air inlet pipe 14. At the same time, the ash can be made to fly around and mix with the combustion aid again, so as to fully burn the waste liquid and improve the efficiency of waste liquid incineration.

[0093] The pressure relief mechanism includes a pressure relief pipe 6, which is installed at the upper end of the incinerator body 1. A pressure buffer storage tank 7 is installed at the output end of the pressure relief pipe 6, and a second electrically controlled valve 5 for controlling the opening and closing of the pressure relief pipe 6 is installed on the side wall of the pressure relief pipe 6.

[0094] During use, when the gas pressure inside the incinerator body 1 rises rapidly and the exhaust pipe 3 cannot expel the flue gas inside the incinerator body 1 in time, as the internal pressure of the incinerator body 1 rises, the gas pressure sensor 16 sends a signal to the controller 4. The controller 4 judges the pressure value. When the pressure value is greater than the set value inside the controller 4, the controller 4 sends a signal to the second electrically controlled valve 5. The second electrically controlled valve 5 opens the pressure relief pipe 6, so that the flue gas inside the incinerator body 1 enters the pressure buffer storage tank 7 through the pressure relief pipe 6, thereby relieving the pressure of the incinerator body 1.

[0095] Compared with existing technologies, by transporting the flue gas inside the incinerator body 1 to the pressure buffer storage tank 7, the pressure of the incinerator body 1 is depressurized, thereby ensuring the safety of waste liquid treatment. At the same time, the flue gas is stored in the pressure buffer storage tank 7 to prevent flue gas leakage and protect the environment.

[0096] The working principle of a waste liquid incinerator:

[0097] In operation, the motor 10 is started, and its output drives the gear 12 to rotate. The gear 12 drives the gear ring 21 to rotate, which in turn drives the waste liquid conveying cylinder 19 to rotate. The waste liquid conveying cylinder 19 then drives the waste liquid spraying pipe 17 and the combustion aid spraying pipe 18 to rotate. Simultaneously, waste liquid is conveyed into the waste liquid conveying cylinder 19 through the waste liquid input pipe 23. The waste liquid passes through the waste liquid conveying cylinder 19 and enters the waste liquid spraying pipe 17, which sprays the waste liquid onto the inside of the incinerator body 1. Combustion aid is conveyed into the combustion aid conveying cylinder 25 through the combustion aid input pipe 24. The combustion aid passes through the combustion aid conveying cylinder 25 and enters the combustion aid spraying pipe 18, which sprays the combustion aid onto the incinerator body 1. Inside the furnace body 1, the waste liquid and the combustion aid are mixed. At the same time, the blower 11 is started. The output end of the blower 11 blows air to the backflow frame 13 through the L-shaped air inlet pipe 14. The backflow frame 13 reflects the air upward, so that the air blows upward. Then the flame injector 15 is started. Under the action of the combustion aid, the waste liquid is burned. As the pressure inside the incinerator body 1 increases, the gas pressure sensor 16 sends the detected gas pressure signal to the controller 4. The controller 4 judges the gas pressure. When the gas pressure reaches the set value inside the controller 4, the controller 4 sends a signal to the first electric control valve 2. The first electric control valve 2 opens the exhaust pipe 3, so that the exhaust pipe 3 outputs the high-temperature flue gas inside the incinerator body 1.

[0098] When the gas pressure inside the incinerator body 1 rises rapidly and the exhaust pipe 3 cannot expel the flue gas inside the incinerator body 1 in time, as the internal pressure of the incinerator body 1 rises, the gas pressure sensor 16 sends a signal to the controller 4. The controller 4 judges the pressure value. When the pressure value is greater than the set value inside the controller 4, the controller 4 sends a signal to the second electrically controlled valve 5. The second electrically controlled valve 5 opens the pressure relief pipe 6, so that the flue gas inside the incinerator body 1 enters the pressure buffer storage tank 7 through the pressure relief pipe 6, thereby relieving the pressure of the incinerator body 1.

[0099] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

Claims

1. A process for treating waste gas, waste liquid, and residue from a DMF recovery device, characterized in that, Includes the following steps: Step 1: DMF is recovered through a DMF recovery device, generating three types of waste: system tail gas, dimethylamine concentrate, and distillation kettle residue. Step 2: The dimethylamine concentrate from Step 1 is fed into a stripping tower for stripping to produce gaseous dimethylamine; Step 3: Mix the gaseous dimethylamine from Step 2 with the system exhaust gas from Step 1, and then add them together into the waste gas incinerator for incineration, while generating high-temperature flue gas. Step 4: Mix the dimethylamine concentrate from Step 1 with the distillation vessel residue from Step 1, and then add them together to the waste liquid incinerator for incineration, while generating high-temperature flue gas. Step 5: The high-temperature flue gas generated in Step 3 and Step 4 is transported together to the waste heat boiler. The waste heat boiler will generate steam to recover the heat energy from combustion. Step Six: The by-product steam from Step Five is transported to the DMF recovery unit to supplement the heat of the DMF recovery unit; Step 7: The steam from Step 5 is transported to the quench tower for desulfurization and denitrification, while preventing the generation of dioxins and discharging clean flue gas. Step 8: The clean flue gas discharged in Step 7 is sent to the air preheater. The air preheater preheats the combustion air of the waste gas incinerator and the waste liquid incinerator to further recover heat. Finally, the air preheater discharges the flue gas through the chimney. At low loads, only the waste liquid incinerator is used; at high loads, both the waste gas incinerator and the waste liquid incinerator are used simultaneously to ensure that the load can be adjusted from 30% to 110%. The waste liquid incinerator includes an incinerator body (1), a mixing spraying mechanism, an air supply mechanism, and a pressure relief mechanism. A bracket (8) is installed at the lower end of the incinerator body (1). A support cylinder (20) is vertically installed at the center of the bottom of the incinerator body (1). A flame jet head (15) for incinerating waste liquid is installed on the inner wall of the incinerator body (1). An exhaust pipe (3) for discharging incinerated gas is installed at the upper end of the incinerator body (1). A first electrically controlled valve (2) for controlling the opening and closing of the exhaust pipe (3) is installed on the side wall of the exhaust pipe (3). A gas pressure sensor (16) for detecting the internal gas pressure of the incinerator body (1) is installed at the top of the incinerator body (1). A controller (4) for receiving the signal from the gas pressure sensor (16) and controlling the first electrically controlled valve (2) is installed at the upper end of the incinerator body (1). The mixing spraying mechanism is located inside the support cylinder (20) and is used to spray the waste liquid and combustion aid together into the interior of the incinerator body (1) so that the waste liquid and combustion aid are fully mixed. The air supply mechanism is located at the bottom of the incinerator body (1) and is used to transport external air into the interior of the incinerator body (1) to provide sufficient oxygen for the interior of the incinerator body (1). The pressure relief mechanism is located at the upper end of the incinerator body (1) and is used to relieve pressure inside the incinerator body (1); The air supply mechanism includes several blowers (11), which are arranged in a circular array on the lower side wall of the incinerator body (1). The bottom of the incinerator body (1) is equipped with a backflow frame (13) corresponding to each blower (11). An L-shaped air inlet pipe (14) is installed at the output end of each blower (11). The end of the L-shaped air inlet pipe (14) away from the blower (11) passes through the side wall of the incinerator body (1) and is positioned above the backflow frame (13). The output end of the L-shaped air inlet pipe (14) is vertically downward. The pressure relief mechanism includes a pressure relief pipe (6), which is installed at the upper end of the incinerator body (1). A pressure buffer storage tank (7) is installed at the output end of the pressure relief pipe (6), and a second electrically controlled valve (5) for controlling the opening and closing of the pressure relief pipe (6) is installed on the side wall of the pressure relief pipe (6).

2. The waste gas and waste liquid residue treatment process of a DMF recovery device according to claim 1, characterized in that, The waste gas incinerator in step three is a horizontal incinerator.

3. The waste gas and waste liquid residue treatment process of a DMF recovery device according to claim 1, characterized in that, The waste gas incinerator in step three is equipped with a high-pressure air supply system.

4. The waste gas and waste liquid residue treatment process of a DMF recovery device according to claim 1, characterized in that, The mixing spraying mechanism includes a waste liquid conveying cylinder (19), which is rotatably connected to the inner wall of a support cylinder (20). A combustion-supporting agent conveying cylinder (25) is vertically installed at the top center of the waste liquid conveying cylinder (19). Both the waste liquid conveying cylinder (19) and the combustion-supporting agent conveying cylinder (25) are rotatably connected to a sealing cap (9). A support rod (22) is installed on the side wall of the sealing cap (9). The end of the support rod (22) away from the sealing cap (9) is installed on the side wall of a bracket (8). A combustion-supporting agent input pipe (24) for conveying combustion-supporting agent into the combustion-supporting agent conveying cylinder (25) is installed on the sealing cap (9) inside the combustion-supporting agent conveying cylinder (25). A waste liquid input pipe (23) for conveying waste liquid into the waste liquid conveying cylinder (19) is installed on the sealing cover (9) between (25) and the waste liquid conveying cylinder (19). An auxiliary combustion agent spraying pipe (18) for spraying auxiliary combustion agent into the incinerator body (1) is installed on the side wall of the auxiliary combustion agent conveying cylinder (25). The end of the auxiliary combustion agent spraying pipe (18) away from the auxiliary combustion agent conveying cylinder (25) passes through the waste liquid conveying cylinder (19) and is horizontally set inside the incinerator body (1). A waste liquid spraying pipe (17) for spraying waste liquid into the incinerator body (1) is horizontally installed on the side wall of the waste liquid conveying cylinder (19). A drive assembly for driving the waste liquid conveying cylinder (19) to rotate is provided inside the bracket (8).

5. The waste gas and waste liquid residue treatment process of a DMF recovery device according to claim 4, characterized in that, The drive assembly includes a gear ring (21), which is mounted on the side wall of the waste liquid conveying cylinder (19) inside the bracket (8). A motor (10) is mounted at the bottom of the bracket (8), and a gear (12) is mounted at the output end of the motor (10). The gear (12) meshes with the gear ring (21).

6. The waste gas and waste liquid residue treatment process of a DMF recovery device according to claim 1, characterized in that, The blower (11) is equipped with a filter cover for filtering air at its input end.

7. The waste gas and waste liquid residue treatment process of a DMF recovery device according to claim 1, characterized in that, The inner wall of the incinerator body (1) is fitted with corundum refractory material and thermal insulation material.

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