Flue gas desulfurization system for treating ammonia-nitrogen-containing wastewater
By combining an absorption tower and a waste liquid treatment unit in the flue gas desulfurization system, the problem of high treatment costs for ammonia nitrogen-containing wastewater has been solved, achieving efficient purification of wastewater and flue gas and reducing treatment costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-23
- Publication Date
- 2026-03-24
AI Technical Summary
Existing technologies for treating ammonia nitrogen-containing wastewater are costly, and traditional methods are difficult to effectively remove ammonia nitrogen from wastewater and sulfur dioxide from flue gas.
A flue gas desulfurization system is adopted, including an absorption tower and a waste liquid treatment unit. Through the chemical reaction in the absorption tower and the combination of hydrocyclones and wastewater treatment mechanisms, the system can treat ammonia nitrogen-containing wastewater and flue gas. Specifically, it includes the reaction of calcium carbide slag slurry, ammonia nitrogen-containing wastewater and sulfur-containing flue gas. Subsequently, the system undergoes multi-stage purification through hydrocyclones and wastewater treatment mechanisms, and finally, the clean water is reused.
It achieves effective treatment of ammonia nitrogen-containing wastewater, while removing sulfur dioxide from flue gas, thus reducing the cost of wastewater and exhaust gas treatment.
Smart Images
Figure CN121715022A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of industrial waste treatment, and in particular to a flue gas desulfurization system for treating ammonia-nitrogen-containing wastewater. BACKGROUND
[0002] Ammonia-nitrogen in water refers to nitrogen in the form of free ammonia and ionic ammonia, which mainly comes from the decomposition of nitrogen-containing organic matter in domestic sewage, industrial wastewater such as coking and synthetic ammonia. High content of ammonia-nitrogen in water will cause eutrophication of surface water, leading to the proliferation of aquatic plants, blue-green algae and other organisms, affecting water quality. Ammonia-nitrogen is toxic to fish and has varying degrees of harm to the human body.
[0003] Therefore, wastewater denitrification treatment has attracted widespread attention. At present, the main denitrification methods include biological nitrification and denitrification, breakpoint chlorination, wastewater stripping method and ion exchange method.
[0004] Among them, the wastewater stripping method is as follows: the material into the wastewater stripping tower has two streams, one is the tail gas from the top of the quenching tower after heat recovery, which is sent to the tail gas separator to separate into two-phase two-stream material. The separated liquid phase is sent to the concentration tower by the concentration pump for concentration, and the gas phase is sent to the recovered urea, and the liquid phase is recovered to the wastewater stripping tower; the second is the centrifugal mother liquor sent to the ammonia stripping tower for stripping, and the gas phase is sent to the ammonia tower. The liquid phase is sent to the wastewater decomposition tower through the flash tank under high temperature and high pressure conditions, and the high polymer in the solution is decomposed into ammonia and carbon dioxide, and the gas phase enters the wastewater stripping tower. After the material is stripped by the wastewater stripping tower, the gas phase is recycled, and the liquid phase is ammonia-nitrogen-containing wastewater.
[0005] However, the ammonia-nitrogen-containing wastewater still needs further treatment, and the cost cannot be ignored. SUMMARY
[0006] Therefore, the present application provides a flue gas desulfurization system for treating ammonia-nitrogen-containing wastewater, and the main purpose is to reduce the cost of wastewater and waste gas treatment.
[0007] To achieve the above purpose, the present application mainly provides the following technical scheme:
[0008] The present application provides a flue gas desulfurization system for treating ammonia-nitrogen-containing wastewater, which comprises: an absorption tower and a waste liquid treatment part.
[0009] The side wall of the absorption tower is connected to a slurry water pipe, an ammonia-nitrogen-containing wastewater pipe and a sulfur-containing flue gas pipe, and the lower end side of the absorption tower is connected to the inlet of a discharge pump and an air blowing fan.
[0010] The waste liquid treatment part comprises a first cyclone, an overflow water tank, a second cyclone and a waste water treatment mechanism, the outlet of the discharge pump, the first cyclone, the overflow water tank, the second cyclone and the waste water treatment mechanism are sequentially connected, the outlet of the waste water treatment mechanism is connected to the inlet of a process water tank, the waste water treatment mechanism is used for removing impurity ions, and the outlet of the process water tank is connected to a demister at the upper end of the absorption tower.
[0011] The purposes and technical problems of the present application can also be further achieved by the following technical measures.
[0012] Optionally, the first cyclone is connected to a vacuum belt dewatering machine, the slag outlet of the vacuum belt dewatering machine is connected to a gypsum tank, the water outlet of the vacuum belt dewatering machine is connected to the water inlet of a steam-water separator, the water outlet of the steam-water separator and the heavy component outlet of the second cyclone are respectively connected to a filtrate water tank, the lower end of the filtrate water tank is connected to the inlet of a filtrate water pump, and the outlet of the filtrate water pump is connected to the side wall of the absorption tower.
[0013] Optionally, the steam outlet of the steam-water separator is connected to the inlet of a vacuum pump, the outlet of the vacuum pump is connected to a flushing water tank, the outlet of the flushing water tank is connected to the inlet of a flushing water pump, and the outlet pipeline of the flushing water pump is directed to the filter cloth of the vacuum belt dewatering machine.
[0014] Optionally, the upper end of the overflow water tank is connected to the filtrate water tank.
[0015] Optionally, the outlet of the process water tank is connected to the filtrate water tank.
[0016] Optionally, the present application further comprises a circulating pump, the inlet of the circulating pump is connected to the lower end of the absorption tower, and the outlet of the circulating pump is connected to the upper end of the absorption tower.
[0017] Optionally, the present application further comprises a stirring mechanism, and the stirring mechanism is installed in the lower space of the absorption tower.
[0018] Optionally, the waste water treatment mechanism comprises aeration adjustment tank, high-efficiency sedimentation tank, sand filter, ultrafilter, ultrafiltrate water tank, cation and anion resin tower, resin water tank, first NF unit, sodium sulfate evaporation unit, centrifuge, mother liquor tank, purification device, second NF unit, NF product water tank, ammonia evaporation device and sodium chloride evaporation crystallization device which are sequentially connected.
[0019] Optionally, the present application further comprises an accident slurry tank, a slurry tank pump is arranged in the accident slurry tank, the outlet of the discharge pump is connected to the accident slurry tank, and the slurry tank pump is connected to the side wall of the absorption tower.
[0020] By the technical scheme, the application has at least the following advantages:
[0021] The carbide slag slurry enters the absorption tower through the slag slurry water pipe, the ammonia-nitrogen-containing wastewater enters the absorption tower through the ammonia-nitrogen-containing wastewater pipe, the sulfur-containing flue gas enters the absorption tower through the sulfur-containing flue gas pipe, and the air is blown into the absorption tower by the air blower, and the following reactions are carried out in the absorption tower:
[0022] SO2+NH4OH+O2→(NH4)2SO4+H2O,(NH4)2SO4+Ca 2+ →CaSO4+NH 4+
[0023] Through the above reactions, the solution in the absorption tower is pumped out by the discharge pump to the first cyclone, the upper layer of the dilute solution in the first cyclone overflows to the overflow water tank, the solution in the overflow water tank is pumped to the second cyclone again, the upper layer of the dilute solution in the second cyclone flows out to the wastewater treatment mechanism, the impurity ions in the solution are removed, the clean water after removing the impurity ions is pumped to the process water tank, and finally recycled to the absorption tower through the demister.
[0024] Through the above-mentioned mode, the ammonia-nitrogen-containing wastewater is treated, and the sulfur dioxide in the flue gas is also removed, thereby reducing the treatment cost of wastewater and waste gas compared with the traditional mode. BRIEF DESCRIPTION OF DRAWINGS
[0025] Figure 1 A structure diagram of a flue gas desulfurization system for treating ammonia-nitrogen-containing wastewater is provided for the embodiments of the application.
[0026] Figure 2 A structure diagram of a first cyclone is provided.
[0027] Figure 3 A process flow diagram of a wastewater treatment mechanism is provided.
[0028] The reference signs in the drawings of the specification include: an absorption tower 1, a discharge pump 2, an air blower 3, a first cyclone 4, an overflow water tank 5, a second cyclone 6, a wastewater treatment mechanism 7, a process water tank 8, a shunt bin 401, a cyclone separator 402, a central water pool 403, a peripheral water pool 404, a vacuum belt dewatering machine 9, a gypsum pool 10, a steam-water separator 11, a filtrate water tank 12, a filtrate water pump 13, a vacuum pump 14, a flushing water tank 15, a flushing water pump 16, a circulating pump 17, a stirring mechanism 18, an accident slurry pool 19, and a slurry pool pump 20. DETAILED DESCRIPTION
[0029] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the specific embodiments, structures, features, and effects according to the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments. In the following description, different "embodiments" or "embodiments" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.
[0030] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.
[0031] An embodiment of the present invention provides a flue gas desulfurization system for treating ammonia nitrogen-containing wastewater, which includes: an absorption tower 1 and a waste liquid treatment unit;
[0032] The side wall of the absorption tower 1 is connected to the slurry water pipe, the ammonia nitrogen wastewater pipe and the sulfur-containing flue gas pipe, and the lower end of the absorption tower 1 is connected to the inlet of the discharge pump 2 and the blower 3.
[0033] The waste liquid treatment unit includes a first hydrocyclone 4, an overflow tank 5, a second hydrocyclone 6, and a wastewater treatment mechanism 7. The outlet of the discharge pump 2, the first hydrocyclone 4, the overflow tank 5, the second hydrocyclone 6, and the wastewater treatment mechanism 7 are connected in sequence. The outlet of the wastewater treatment mechanism 7 is connected to the inlet of the process water tank 8. The wastewater treatment mechanism 7 is used to remove impurity ions. The outlet of the process water tank 8 is connected to the demister at the top of the absorption tower 1.
[0034] The working process of a flue gas desulfurization system for treating ammonia nitrogen-containing wastewater is as follows:
[0035] Calcium carbide slag slurry enters absorption tower 1 through the slurry water pipe, ammonia nitrogen-containing wastewater enters absorption tower 1 through the ammonia nitrogen wastewater pipe, and sulfur-containing flue gas enters absorption tower 1 through the sulfur-containing flue gas pipe. At the same time, the blower 3 blows air into absorption tower 1, and the following reactions take place inside absorption tower 1:
[0036] SO2+NH4OH+O2→(NH4)2SO4+H2O,(NH4)2SO4+Ca 2+ →CaSO4+NH 4+
[0037] Through the above reaction, the discharge pump 2 pumps the solution in the absorption tower 1 to the first hydrocyclone 4. The upper layer of dilute solution in the first hydrocyclone 4 overflows to the overflow tank 5. The solution in the overflow tank 5 is then pumped to the second hydrocyclone 6. The upper layer of dilute solution in the second hydrocyclone 6 flows out to the wastewater treatment unit 7 to remove impurity ions from the solution. The purified water after removing impurity ions is pumped to the process water tank 8 and finally recycled back to the absorption tower 1 through the demister.
[0038] The above method treats ammonia-nitrogen-containing wastewater and removes sulfur dioxide from flue gas, reducing the cost of wastewater and waste gas treatment compared to traditional methods.
[0039] Specifically, the first hydrocyclone 4 and the second hydrocyclone 6 have the same structure. Taking the first hydrocyclone 4 as an example, the first hydrocyclone 4 includes a diversion chamber 401, multiple cyclone separators 402, a central water tank 403, and an outer water tank 404. The outlet of the discharge pump 2 is connected to the lower end of the diversion chamber 401. The upper periphery of the diversion chamber 401 is connected to the tangential inlets of multiple cyclone separators 402. The upper outlet pipe of the cyclone separator 402 points to the central water tank 403, and the lower outlet pipe of the cyclone separator 402 points to the outer water tank 404. The central water tank 403 is connected to the overflow tank 5 to transport the upper layer of dilute solution from the cyclone separator 402 to the overflow tank 5. The outer water tank 404 is connected to the vacuum belt dehydrator 9 to transport the lower layer of concentrated calcium sulfate solution from the cyclone separator 402 to the vacuum belt dehydrator 9.
[0040] In a specific embodiment, a vacuum belt dewatering machine 9 is also included. The heavy component discharge outlet of the first hydrocyclone 4 is connected to the vacuum belt dewatering machine 9. The slag discharge outlet of the vacuum belt dewatering machine 9 is connected to the gypsum storage tank 10. The drain outlet of the vacuum belt dewatering machine 9 is connected to the inlet of the steam-water separator 11. The drain outlet of the steam-water separator 11 and the heavy component discharge outlet of the second hydrocyclone 6 are respectively connected to the filtrate tank 12. The lower end of the filtrate tank 12 is connected to the inlet of the filtrate pump 13. The outlet of the filtrate pump 13 is connected to the side wall of the absorption tower 1.
[0041] In this embodiment, specifically, through centrifugal separation by the first hydrocyclone 4, the calcium sulfate solution reaches the vacuum belt dehydrator 9, and the dehydrated calcium sulfate reaches the gypsum storage tank 10. The water removed by the vacuum belt dehydrator 9 enters the steam-water separator 11 and the filtrate tank 12 in sequence. The calcium sulfate is collected in the gypsum storage tank 10 to achieve the purpose of hazardous waste reuse.
[0042] In a specific embodiment, the exhaust port of the steam-water separator 11 is connected to the inlet of the vacuum pump 14, the outlet of the vacuum pump 14 is connected to the rinsing water tank 15, the outlet of the rinsing water tank 15 is connected to the inlet of the rinsing water pump 16, and the outlet pipe of the rinsing water pump 16 points to the filter cloth of the vacuum belt dewatering machine 9.
[0043] In this embodiment, specifically, the vacuum pump 14 creates a negative pressure environment for the vacuum belt dewatering machine 9 by pumping air, and the gas-water mixture in the gas-water separator 11 reaches the rinsing water tank 15. At the same time, the rinsing water tank 15 also receives industrial makeup water, so that the rinsing water pump 16 can provide sufficient rinsing water to the vacuum belt dewatering machine 9.
[0044] In a specific embodiment, the upper end of the overflow tank 5 is connected to the filtrate tank 12.
[0045] In this embodiment, specifically, when the liquid level in the overflow tank 5 is high, the liquid therein can also overflow into the filtrate tank 12.
[0046] In a specific embodiment, the outlet of the process water tank 8 is connected to the filtrate water tank 12.
[0047] In this embodiment, specifically, when the liquid level in the process water tank 8 is high, the liquid therein can also be transported to the filtrate water tank 12.
[0048] In a specific embodiment, a circulation pump 17 is also included, the inlet of which is connected to the lower end of the absorption tower 1, and the outlet of which is connected to the upper end of the absorption tower 1.
[0049] In this embodiment, specifically, the circulating pump 17 drives the spray liquid in the absorption tower 1 to circulate, thereby improving the efficiency of spray desulfurization.
[0050] In a specific embodiment, a stirring mechanism 18 is also included, which is installed in the lower space of the absorption tower 1.
[0051] In this embodiment, specifically, the solutes such as calcium sulfate at the bottom of the absorption tower 1 will not settle due to the stirring mechanism 18, which facilitates the discharge of the calcium sulfate solution with uniform concentration from the absorption tower 1 by the discharge pump 2.
[0052] In a specific embodiment, the wastewater treatment unit 7 includes, in sequence, an aeration regulating tank, a high-efficiency sedimentation tank, a sand filter, an ultrafilter, an ultrafiltration product water tank, an anion and cation exchange resin tower, a resin water tank, a first NF unit, a sodium sulfate evaporation unit, a centrifuge, a mother liquor tank, a purification device, a second NF unit, an NF product water tank, an ammonia stripping device, and a sodium chloride evaporation and crystallization device.
[0053] In this embodiment, specifically, after two solid-liquid separations by hydrocyclones, the clear liquid discharged from the hydrocyclones passes through various devices of the wastewater treatment unit 7 in sequence, ultimately removing impurity ions from the clear liquid. This avoids the high content of impurity ions in the recycled water in the process water tank 8 and prevents severe corrosion of equipment such as the absorption tower 1.
[0054] In a specific embodiment, it also includes an emergency slurry tank 19, in which a slurry tank pump 20 is installed. The outlet of the discharge pump 2 is connected to the emergency slurry tank 19, and the slurry tank pump 20 is connected to the side wall of the absorption tower 1.
[0055] In this embodiment, specifically, when special circumstances such as the need for maintenance of the absorption tower 1 occur, the discharge pump 2 can pump the solution at the bottom of the absorption tower 1 to the emergency slurry pool 19. At the same time, after the absorption tower 1 is running normally, the slurry pool pump 20 can pump the solution in the emergency slurry pool 19 back to the absorption tower 1, thereby improving the process adaptability of the device.
[0056] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A flue gas desulfurization system for treating wastewater containing ammonia nitrogen, characterized in that, include: An absorption tower, the sidewall of which is connected to a slurry water pipe, an ammonia nitrogen wastewater pipe and a sulfur-containing flue gas pipe, and the lower end of which is connected to the inlet of a discharge pump; The waste liquid treatment unit includes a first hydrocyclone, an overflow tank, a second hydrocyclone, and a wastewater treatment mechanism. The outlet of the discharge pump, the first hydrocyclone, the overflow tank, the second hydrocyclone, and the wastewater treatment mechanism are connected in sequence. The outlet of the wastewater treatment mechanism is connected to the inlet of the process water tank. The wastewater treatment mechanism is used to remove impurity ions. The outlet of the process water tank is connected to the demister at the top of the absorption tower.
2. The flue gas desulfurization system for treating ammonia nitrogen-containing wastewater according to claim 1, characterized in that, It also includes a vacuum belt dewatering machine, the heavy component discharge outlet of the first hydrocyclone is connected to the vacuum belt dewatering machine, the slag discharge port of the vacuum belt dewatering machine is connected to the gypsum storage tank, the drain outlet of the vacuum belt dewatering machine is connected to the inlet of the steam-water separator, the drain outlet of the steam-water separator and the heavy component discharge outlet of the second hydrocyclone are respectively connected to the filtrate tank, the lower end of the filtrate tank is connected to the inlet of the filtrate pump, and the outlet of the filtrate pump is connected to the side wall of the absorption tower.
3. The flue gas desulfurization system for treating ammonia nitrogen-containing wastewater according to claim 2, characterized in that, The exhaust port of the steam-water separator is connected to the inlet of the vacuum pump, the outlet of the vacuum pump is connected to the rinsing water tank, the outlet of the rinsing water tank is connected to the inlet of the rinsing water pump, and the outlet pipe of the rinsing water pump points to the filter cloth of the vacuum belt dewatering machine.
4. The flue gas desulfurization system for treating ammonia nitrogen-containing wastewater according to claim 2, characterized in that, The upper end of the overflow tank is connected to the filtrate tank.
5. The flue gas desulfurization system for treating ammonia nitrogen-containing wastewater according to claim 2, characterized in that, The outlet of the process water tank is connected to the filtrate water tank.
6. The flue gas desulfurization system for treating ammonia nitrogen-containing wastewater according to claim 1, characterized in that, It also includes a circulation pump, the inlet of which is connected to the lower end of the absorption tower, and the outlet of which is connected to the upper end of the absorption tower.
7. The flue gas desulfurization system for treating ammonia nitrogen-containing wastewater according to claim 1, characterized in that, It also includes a stirring mechanism, which is installed in the lower space of the absorption tower.
8. The flue gas desulfurization system for treating ammonia nitrogen-containing wastewater according to any one of claims 1 to 7, characterized in that, The wastewater treatment unit includes, in sequence, an aeration regulating tank, a high-efficiency sedimentation tank, a sand filter, an ultrafilter, an ultrafiltration product water tank, an anion and cation exchange resin tower, a resin water tank, a first NF unit, a sodium sulfate evaporation unit, a centrifuge, a mother liquor tank, a purification device, a second NF unit, an NF product water tank, an ammonia stripping device, and a sodium chloride evaporation and crystallization device.
9. The flue gas desulfurization system for treating ammonia nitrogen-containing wastewater according to any one of claims 1 to 7, characterized in that, It also includes an emergency slurry tank, in which a slurry tank pump is installed, the outlet of the discharge pump is connected to the emergency slurry tank, and the slurry tank pump is connected to the side wall of the absorption tower.