Feeding system and process of high-temperature organic wastewater treatment device

Abstract

The invention discloses a feeding system of an organic wastewater treatment device. The feeding system comprises a gasifier mixer, a steam supply end, a burner and a pipeline, according to the flowing direction of steam in the mixer, the mixer sequentially comprises a rotational flow atomization section, a throttling atomization section and a vortex atomization section, and the rotational flow atomization section, the throttling atomization section and the vortex atomization section are communicated. The rotational flow atomizing section is a cavity I, a rotational flow atomizing nozzle is arranged in the cavity I, the cavity I is provided with an organic wastewater inlet, and the organic wastewater inlet is communicated with the rotational flow atomizing nozzle; the throttling atomization section is a cavity II, the cavity II comprises an upper section and a lower section, the upper section is reduced, and the lower section is expanded; the vortex atomization section comprises a cavity III, and a structure for generating vortex is arranged in the cavity III. The steam enters the rotational flow atomization section, the organic wastewater enters the rotational flow atomization nozzle, and the steam and the organic wastewater sprayed by the rotational flow atomization nozzle sequentially pass through the throttling atomization section and the vortex atomization section and then are discharged through the vortex atomization section; and steam discharged from the vortex atomization section and organic wastewater enter the gasification furnace through the burner.

Description

Technical Field

[0001] The invention relates to the technical field of chemical industry, and in particular to a feeding system and process of a high-temperature organic wastewater treatment device. Background Art

[0002] With the rapid development of the national economy, people's living standards have been significantly improved. At the same time, the output of urban domestic sewage, chemical wastewater and waste liquid has also increased sharply. my country's petrochemical, metallurgical, papermaking, leather, fermentation, pharmaceutical, textile printing and dyeing industries produce tens of thousands of tons of organic waste liquid every year. The organic waste liquid discharged by these industries is not only large in quantity and high in concentration, but some also contain toxic and harmful substances, which poses a severe challenge to our living environment and ecology.

[0003] There are a lot of organic pollutants in organic waste liquid. Because its molecules contain more carbon and hydrogen elements, it is a new concept of resource and ecological harmony to regard it as a potential resource instead of simply treating it as a polluted waste. Using it as a raw material for some chemical products can not only effectively utilize organic pollutants and prevent the harm of pollutants from the source, but also generate a new profit model through the production of chemicals. It will be the most environmentally friendly and effective way to manage and utilize organic waste liquid in the future.

[0004] The resource utilization of high-concentration organic waste liquid refers to the reuse of valuable components remaining in the wastewater or the reuse of water resources after the wastewater is treated. To this end, environmental protection workers at home and abroad have developed many high-concentration organic waste liquid resource utilization technologies based on the characteristics of organic waste liquid, and have achieved good results. They are mainly divided into the following three categories: (1) oxidation and biochemical treatment; (2) incineration treatment; (3) combustion or gasification of waste liquid and wastewater coal slurry.

[0005] Oxidation and biochemical treatment methods. In the biochemical treatment method, toxic and harmful substances in organic wastewater can easily cause the inactivation of biochemical bacteria. It is necessary to build physical and chemical pretreatment equipment to ensure the efficiency of biochemical treatment. The biochemical treatment method is only suitable for treating low-concentration organic wastewater.

[0006] Incineration treatment refers to the destruction of the molecular structure of various harmful substances in wastewater through controlled high-temperature chemical reactions in the combustion chamber of the incinerator, and the oxidation of organic matter in the wastewater into harmless substances such as CO and H2O. It is suitable for treating high-concentration organic wastewater. However, the main components of the tail gas produced by the incineration of organic wastewater are steam, smoke, SO2, NO2, etc. In order to ensure that the tail gas meets the emission standards, it is necessary to build auxiliary equipment such as quenching, desulfurization, and denitrification. Large investment, high operating costs, and low returns are the main factors restricting the promotion and application of incineration treatment technology for organic wastewater.

[0007] The flame temperature in the gasifier, the core of the fluidized-flow gasification technology, is generally 2000°C. At this high temperature, organic matter will decompose and burn into inorganic gas. Fluidized-flow gasification has inherent advantages in treating organic matter in waste liquid. At the same time, harmful substances such as organic matter in waste liquid can undergo gasification reaction in the gasifier to generate synthesis gas. However, at present, there are many types of fluidized-flow technologies in my country, and the raw materials are complex. The transformation of existing fluidized-flow gasification devices to mix and burn organic wastewater is not only limited by the structure of the gasifier equipment, but also by the nature of the gasification raw materials. The high transformation investment and large engineering workload restrict the promotion and application of fluidized-flow gasification technology for treating organic wastewater.

[0008] The feeding systems and processes of the high-temperature treatment of organic wastewater devices in the prior art mainly include: a composite gasification burner and process method for pulverized coal mixed with high-concentration organic wastewater disclosed in a Chinese patent application (CN107189820A). The process method is that pulverized coal and organic wastewater are sent to the burner through a conveying pipeline, and the burner ignition gun is separately externalized, and the pulverized coal feeding and wastewater mixed combustion of the burner are set as independent channels, the ignition and start-up purge gas are in the same channel, the organic wastewater oxygen and the start-up oxygen are in the same channel, and the pulverized coal channel is set in the outer ring of the burner and other gasifier structure improvements to realize the organic wastewater mixed combustion process in pulverized coal gasification.

[0009] A Chinese patent application (CN113266836A) discloses a gasifier feeding process for treating organic waste liquid, wherein the organic waste liquid feeding system includes an organic waste liquid buffer tank, an organic waste liquid feeding pump and a waste liquid burner.

[0010] A pulverized coal gasification device and a process method for burning organic wastewater therein are disclosed in a Chinese patent application (CN112226248A). The gasifier is provided with an interface for installing an ignition burner. The pulverized coal gasification device also includes a wastewater nozzle, which can also be installed on the interface. The original function of the interface was to install the ignition burner, but now it is used to install the wastewater nozzle. There is no need to modify the gasifier or set a special waste liquid inlet on the gasifier. In this way, the original interface of the gasifier is fully utilized and combined with the newly added wastewater nozzle to atomize the wastewater.

[0011] The organic wastewater co-combustion process in the prior art still has the following problems:

[0012] (1) The adjustable range of organic wastewater feed temperature is narrow and it is difficult to reach above 300°C. For heavy oil gasification burners, low-temperature fluid will reduce the burner temperature. The temperature reduction will cause a significant increase in the viscosity of the heavy oil, which will lead to excessive burner pressure difference, which will seriously affect the operation of the device. The existing organic wastewater addition technology will be limited by the generation of gasification raw materials;

[0013] (2) The adjustable range of organic wastewater feed flow is narrow. Since organic wastewater is directly sprayed into the gasifier through a nozzle, the feed needs to ensure that the minimum flow of wastewater is atomized in the wastewater nozzle. However, organic wastewater is generally three wastes from chemical plants, not products, and some organic reactors are operated intermittently, with large flow fluctuations. The existing organic wastewater addition technology is difficult to adapt to excessive flow fluctuations. In severe cases, the wastewater burner needs to be started and stopped frequently;

[0014] (3) The low-temperature liquid is directly sprayed into the gasifier through the liquid phase, which has a great impact on the temperature field and flow field in the gasifier. This addition method has poor stability. In order to reduce the impact on the long-term operation of the device and the product quality, a separate wastewater nozzle must be set to reduce the impact on the flow field in the gasifier. This makes the system complex and increases the cost of the device to a certain extent. Some technologies even require the gasifier to be modified to optimize the temperature field and flow field in the furnace. Summary of the invention

[0015] In order to solve the above problems in the prior art, the present invention proposes a feeding system and process for an organic wastewater treatment device.

[0016] In a first aspect, the present invention provides a feeding system for an organic wastewater treatment device, wherein the organic wastewater treatment device is a gasifier;

[0017] The feeding system includes: a mixer, a steam supply end, a burner and a pipeline; the steam supply end stores steam;

[0018] According to the flow direction of steam in the mixer, the mixer includes a swirl atomization section, a throttling atomization section and a vortex atomization section in sequence, and the swirl atomization section, the throttling atomization section and the vortex atomization section are connected to each other, and the steam flows through the swirl atomization section, the throttling atomization section and the vortex atomization section in sequence in the mixer; specifically, the swirl atomization section, the throttling atomization section and the vortex atomization section are fixedly connected or detachably connected.

[0019] The swirl atomization section is a cavity I, a swirl atomization nozzle is arranged inside the cavity I, an organic wastewater inlet is arranged in the cavity I, and the organic wastewater inlet is connected to the swirl atomization nozzle; a swirl atomizer is arranged inside the swirl atomization nozzle.

[0020] The throttling atomization section is cavity II, and cavity II includes an upper section and a lower section, the upper section is a reduced diameter section, and the lower section is an expanded diameter section; the length of the upper section is shorter than that of the lower section;

[0021] The vortex atomization section includes a cavity III, and a structure for generating vortex is arranged inside the cavity III; specifically, after the fluid enters the vortex atomization section, the fluid can generate vortex in the vortex atomization section under the action of the structure for generating vortex.

[0022] The structure for generating eddy current in the present invention may be a structure for generating eddy current in the prior art.

[0023] The steam discharged from the steam supply end enters the swirl atomization section through pipeline I, and the organic wastewater enters the swirl atomization nozzle through the organic wastewater inlet. After the steam and the organic wastewater sprayed from the swirl atomization nozzle are mixed, they pass through the throttling atomization section and the vortex atomization section in sequence and are discharged from the vortex atomization section; the steam discharged from the vortex atomization section and the organic wastewater enter the gasifier from the burner through pipeline II.

[0024] Steam enters cavity I through the top of cavity I, and organic wastewater enters the swirl atomizer nozzle through the organic wastewater inlet, and is sprayed out from the swirl atomizer nozzle after being atomized for the first time by the swirl atomizer.

[0025] The organic wastewater sprayed from the swirl atomizing nozzle is mixed with steam and enters cavity II. In cavity II, a high-speed fluid is formed after the upper section is reduced and throttled. The high-speed fluid enters the lower section. The throttled high-speed fluid quickly diffuses in the lower section and forms a partial negative pressure area. Strong turbulence is generated in this area. The organic wastewater is further atomized in this section and further mixed with steam to form aerosol I. Aerosol I includes organic wastewater droplets and steam. Aerosol I is discharged from cavity II.

[0026] Aerosol I enters the vortex atomization section (cavity III), and the organic wastewater droplets and steam fully transfer heat and mass in the vortex atomization section. Part of the organic wastewater on the surface of the organic wastewater droplets is vaporized at this stage, and the diameter of the organic wastewater droplets is further reduced. The organic wastewater is further atomized in this section, and the organic wastewater and steam form aerosol II, which is discharged from the bottom of cavity III. The aerosol II discharged from cavity III enters the gasifier through the burner.

[0027] As a specific embodiment of the present invention, the structure for generating vortex atomization is a plurality of cross levers arranged sequentially from top to bottom inside the cavity III. The levers in the present invention may be levers of other structures capable of generating vortex in the fluid inside the cavity III.

[0028] Preferably, the cross lever includes an intersection and four sides, the four sides are arranged in cavity III, the four sides are equal in length, the intersection is on the same straight line in the vertical direction, and the four sides of several cross levers do not overlap in the bottom view of cavity III.

[0029] As a specific embodiment of the present invention, the feeding system also includes a buffer tank, in which organic wastewater is stored. The buffer tank includes a buffer tank outlet and a buffer tank reflux port, and the buffer tank outlet is connected to the organic wastewater inlet through a pipeline III.

[0030] Specifically, the buffer tank is a sealed tank body.

[0031] As a specific embodiment of the present invention, the feeding system further comprises a booster pump, which is arranged in pipeline III and located between the buffer tank and the mixer.

[0032] As a specific embodiment of the present invention, the burner is a compound burner.

[0033] As a specific implementation of the present invention, pipeline III is also provided with a flow regulating valve 1 and a cut-off valve 1, wherein the flow regulating valve 1 is located between the increasing pump and the mixer; and the cut-off valve 1 is located between the flow regulating valve 1 and the mixer.

[0034] As a specific implementation of the present invention, the reflux port and the increasing pump are connected via a pipeline IV, and a second cut-off valve is provided on the pipeline IV.

[0035] As a specific embodiment of the present invention, the buffer tank includes a pressure regulating valve 1 and a pressure regulating valve 2. The pressure regulating valve 1 and the pressure regulating valve are used to regulate the pressure in the buffer tank.

[0036] As a specific embodiment of the present invention, the buffer tank further includes a safety valve and a cut-off valve 3. The safety valve has an automatic pressure relief function to ensure the safety of the buffer tank. The cut-off valve 3 is used to control whether the organic wastewater from the upstream enters the buffer pipe.

[0037] As a specific embodiment of the present invention, a flow regulating valve 2 and a cut-off valve 4 are provided in the pipeline 1. The flow regulating valve 2 is used to regulate the gas flow entering the mixer, and the cut-off valve 4 is used to control whether the gas enters the mixer.

[0038] In a second aspect, the present invention provides a feeding process for an organic wastewater treatment device, using the feeding system for the organic wastewater treatment device provided in the first aspect of the present invention, comprising the following steps:

[0039] Step 1: Steam from the steam supply end enters the cyclone atomization section, and organic wastewater enters the cyclone atomization nozzle from the organic wastewater inlet. The organic wastewater is atomized by the cyclone atomization nozzle and then sprayed out;

[0040] Step 2: The organic wastewater sprayed from the swirl atomization nozzle and the steam enter the throttling atomization section together. In the throttling atomization section, the organic wastewater continues to be atomized and is mixed with the steam to form aerosol I, which is discharged from the throttling atomization section;

[0041] Step 3: Aerosol I enters the vortex atomization section, and the organic wastewater in the aerosol I continues to be atomized in the vortex atomization section. The atomized organic wastewater and steam form aerosol II, which is discharged from the vortex atomization section and enters the gasifier through the burner.

[0042] As a specific embodiment of the present invention, in step 1, the organic wastewater is collected by the buffer tank and then discharged from the outlet of the buffer tank. The organic wastewater discharged from the outlet of the buffer tank enters the cyclone atomization section.

[0043] As a specific embodiment of the present invention, the organic wastewater discharged from the outlet of the buffer tank enters the cyclone atomization section under the action of the booster pump.

[0044] As a specific embodiment of the present invention, in step one, the flow rate of the organic wastewater discharged from the outlet of the buffer tank is controlled by a flow regulating valve one during the process of entering the cyclone atomization section.

[0045] As a specific embodiment of the present invention, the flow rate of organic wastewater discharged from the outlet of the buffer tank is 0-35 t / h.

[0046] As a specific embodiment of the present invention, the mass ratio of the organic wastewater entering the gasifier to the mass ratio of the coal fed into the gasifier is 1:5. This mass ratio is a dry basis mass ratio.

[0047] As a specific embodiment of the present invention, the mass ratio of the organic wastewater entering the gasifier to the amount of coal fed into the gasifier is less than 1:5. This mass ratio is a dry basis mass ratio.

[0048] As a specific embodiment of the present invention, the amount of steam used per ton of organic wastewater is greater than 20m 3 .

[0049] As a specific embodiment of the present invention, the amount of steam used per ton of organic wastewater is equal to 20m 3 .

[0050] In order to ensure the atomization effect of organic wastewater, the amount of steam used per ton of organic wastewater must be no less than 20m 3 .

[0051] As a specific embodiment of the present invention, the flow rate of steam is greater than 100m 3 / h.

[0052] As a specific embodiment of the present invention, the flow rate of steam is equal to 100m 3 / h.

[0053] When no organic wastewater is added to the mixer or the amount of organic wastewater is small, in order to ensure that the continuous operation of the system is not affected, the steam flow rate must be greater than or equal to 100m 3 / h.

[0054] As a specific embodiment of the present invention, after the feeding system of the organic wastewater treatment device is started, the shut-off valve one is closed first, and the shut-off valve two is opened. The booster pump controls the organic wastewater to flow back to the buffer tank through the reflux port. After the outlet pressure of the booster pump is stable, the shut-off valve one is opened, and the shut-off valve two is closed. The booster pump controls the organic wastewater to enter the mixer.

[0055] As a specific embodiment of the present invention, before closing the feed system of the organic wastewater treatment device, first close the cut-off valve 1 and then close the adding pump, so that the organic wastewater adding system can operate independently of the gasifier system.

[0056] As a specific implementation of the present invention, during the reaction process, the pressure in the buffer tank is controlled by adjusting the pressure regulating valve 1 and the pressure regulating valve 2.

[0057] As a specific implementation of the present invention, whether the organic wastewater enters the buffer tank is controlled by the cut-off valve three.

[0058] As a specific implementation of the present invention, the safety of the buffer tank is ensured by the automatic pressure relief function of the safety valve.

[0059] As a specific embodiment of the present invention, the flow rate of steam entering the mixer is controlled by adjusting the flow regulating valve 2, and the temperature of the organic wastewater discharged from the vortex atomization section is adjusted by controlling the flow rate of the gas.

[0060] As a specific implementation of the present invention, whether the gas enters the mixer is controlled by a cut-off valve 9.

[0061] In a third aspect, the present invention provides an application of a feeding system for an organic wastewater treatment device provided in the first aspect of the present invention or a feeding process for treating organic wastewater provided in the second aspect of the present invention in treating organic wastewater, wherein the organic wastewater is organic wastewater generated by coal chemical industry or organic wastewater generated by petrochemical industry.

[0062] Preferably, the organic wastewater is one of organic wastewater generated by an MTO device, organic wastewater generated by a PDH device, and organic wastewater generated by an EVA device. Since the organic wastewater generated by an MTO device, a PDH device, and an EVA device has a high calorific value, a low boiling point, and high volatility, the economic benefits are good when the organic wastewater is treated by the feed system and process of the organic wastewater treatment device of the present invention.

[0063] The MTO unit is a methanol to olefins unit, the PDH unit is a propane dehydrogenation unit, and the EVA unit is an ethylene vinyl acetate unit.

[0064] Because the gasifier has a coaxial restricted jet flow field structure, there are jet zones and recirculation zones. The recirculation zone is larger and has greater intensity. The liquid phase feed of organic wastewater has a great disturbance on the original flow field and the particle residence time is greatly affected. In severe cases, it leads to insufficient reaction in some areas. The gas phase feed can optimize the particle residence time distribution and create conditions for promoting coal char reaction.

[0065] When organic waste liquid is fed in liquid phase at low temperature, it evaporates rapidly after entering the gasifier and a decomposition reaction occurs. The decomposition area is larger than that of coal and occurs earlier, which will eventually cause the secondary reaction area of ​​​​the coal char to move downward, reducing the carbon conversion rate of the original reaction. When the organic waste liquid is fed in gas phase at high temperature, a decomposition reaction occurs directly after entering the gasifier, which greatly reduces the downward effect of the secondary reaction area of ​​​​the coal char and has little effect on the carbon conversion rate of the original reaction.

[0066] When the amount of oxygen and coal flow rate are constant, the addition of waste liquid will cause the temperature of the gasifier to drop because the waste liquid conversion needs to absorb heat and lower the temperature. However, the gas-phase high-temperature feed has a much smaller impact on the reaction temperature and temperature field in the gasifier than the liquid-phase low-temperature feed in the prior art.

[0067] Based on the above findings, the present invention provides a process system and method that can stably and reliably deliver wastewater into a gasifier. Through the structural design of the mixer, organic wastewater can enter the gasifier in the form of gas or tiny droplets, so that after the organic wastewater enters the gasifier, it has little effect on the temperature field, flow field, etc. in the furnace, will not affect the process operability and product quality, and there is no need to modify the existing equipment.

[0068] The feeding system of the organic wastewater treatment device in the present invention provides a method for feeding organic wastewater in a gasifier, and controls the flow rate of steam entering the mixer to achieve controllable feeding temperature of organic wastewater, making it suitable for gasifiers of various processes and raw materials.

[0069] The feeding system of the organic wastewater treatment device provided by the present invention has high operational flexibility. An additional pump, a shut-off valve one and a shut-off valve two are arranged on the pipeline of the system. During operation, the additional pump, the shut-off valve one and the shut-off valve two cooperate with the buffer tank and the mixer to achieve no minimum flow limit for the organic wastewater feed amount in the gasifier, a wide adjustable range, and the operational stability of the gasifier will not be affected by fluctuations in the organic wastewater feed amount. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 This is a schematic diagram of a feeding system of an organic wastewater treatment device in Example 2 of the present invention;

[0071] Figure 2 is a structural diagram of a mixer in Example 2 of the present invention;

[0072] Figure 3 This is a structural diagram of a swirl atomizing nozzle in Example 2 of the present invention;

[0073] Figure 4 This is the BB view of the cyclone atomizer in Example 2 of the present invention;

[0074] Figure 5 It is a side view of the cyclone atomizer in Example 2 of the present invention;

[0075] Figure 6 This is the AA view of the vortex mixer in Example 2 of the present invention;

[0076] Figure 7 It is the temperature field variation diagram in the gasifier;

[0077] Among them, 1-buffer tank, 11-pressure regulating valve 1, 12-pressure regulating valve 2, 13-safety valve, 14-shut-off valve 3;

[0078] 2-mixer, 21-swirl atomization section, 211-cavity I, 212-swirl atomization nozzle, 213-organic wastewater inlet, 2121-swirl atomizer, 2122-atomization nozzle head;

[0079] 22-throttling atomization section, 221-chamber II, 222-upper section, 223-lower section;

[0080] 23- vortex atomization section, 231- cavity III, 232- cross lever;

[0081] 3-burner;

[0082] 4-Steam supply end;

[0083] 5- pipeline, 51- pipeline I, 52- pipeline II, 53- pipeline III, 54- pipeline IV;

[0084] 6-boosting pump; 7-flow regulating valve one; 8-cut-off valve one; 9-cut-off valve two, 10-flow control valve two; 101-cut-off valve four. DETAILED DESCRIPTION

[0085] The present invention will be further described below in conjunction with specific embodiments, but they do not constitute any limitation to the present invention.

[0086] Example 1

[0087] The feeding system of an organic wastewater treatment device is a gasifier; the feeding system comprises: a mixer, a steam supply end, a burner and a pipeline; the steam supply end stores steam; the mixer is placed in a vertical direction, and the mixer comprises a swirl atomization section, a throttling atomization section and a vortex atomization section from front to back, and the swirl atomization section, the throttling atomization section and the vortex atomization section are connected; the swirl atomization section is a cavity I, a swirl atomization nozzle is arranged inside the cavity I, a swirl atomizer is arranged inside the swirl atomization nozzle, an organic wastewater inlet is arranged in the cavity I, and the organic wastewater inlet is connected to the swirl atomization nozzle; the throttling atomization section is a cavity II, and the cavity II comprises an upper section and a lower section, the upper section is a reduced diameter, and the lower section is an expanded diameter; the vortex atomization section is a cavity III, and a structure for generating vortex atomization is arranged inside the cavity III.

[0088] The steam discharged from the steam supply end enters the swirl atomization section through pipeline I, and the organic wastewater enters the swirl atomization nozzle through the organic wastewater inlet. The steam and organic wastewater pass through the throttling atomization section and the vortex atomization section and are discharged from the vortex atomization section; the steam and organic wastewater discharged from the vortex atomization section enter the gasifier from the burner through pipeline II.

[0089] Steam enters cavity I through the top of cavity I, and organic wastewater enters the cyclone atomizer nozzle through the organic wastewater inlet, and is sprayed out from the cyclone atomizer nozzle after being atomized for the first time by the cyclone atomizer;

[0090] The organic wastewater sprayed from the swirl atomizing nozzle is mixed with steam and enters cavity II. In cavity II, a high-speed fluid is formed after the upper section is reduced and throttled. The high-speed fluid enters the lower section. The throttled high-speed fluid quickly diffuses in the lower section and forms a partial negative pressure area. Strong turbulence is generated in this area. The organic wastewater is further atomized in this section and further mixed with steam to form aerosol I. Aerosol I includes organic wastewater droplets and steam. Aerosol I is discharged from cavity II.

[0091] Aerosol I enters the vortex atomization section (cavity III), and the organic wastewater droplets and steam fully transfer heat and mass in the vortex atomization section. Part of the organic wastewater on the surface of the organic wastewater droplets is vaporized at this stage, and the diameter of the organic wastewater droplets is further reduced. The organic wastewater is further atomized in this section, and the organic wastewater and steam form aerosol II, which is discharged from the bottom of cavity III. The aerosol II discharged from cavity III enters the gasifier through the burner.

[0092] Example 2

[0093] like Figure 2As shown, a feeding system for an organic wastewater treatment device, the device for treating organic wastewater is a gasifier, the feeding system includes a buffer tank 1, a mixer 2, a burner 3, a steam supply end 4, a pipeline 5 and a booster pump; the buffer tank 1 stores organic wastewater; the steam supply end 4 stores steam, the mixer 2 is placed in a vertical direction, the mixer 2 includes a swirl atomization section 21, a throttling atomization section 22 and a vortex atomization section 23 from front to back, the swirl atomization section 21, the throttling atomization section 22 and the vortex atomization section 23 are connected by flanges, and the swirl atomization section 21, the throttling atomization section 22 and the vortex atomization section 23 are connected; the swirl atomization section includes a cavity I211, a swirl atomization nozzle 212 is arranged inside the cavity I211, and the swirl atomization nozzle 212 includes a swirl atomizer 2121 and an atomization nozzle The head 2122, the cavity I211 is provided with an organic wastewater inlet 213, and the organic wastewater inlet 213 is connected with the swirl atomizing nozzle 212; the throttling atomizing section 22 is a cavity II221, and the cavity II221 includes an upper section 222 and a lower section 223, the upper section 222 is a reduced diameter, and the lower section 223 is an expanded diameter, and the length of the lower section 223 is greater than the length of the upper section 222; the swirl atomizing section 23 includes a cavity III231, and the interior of the cavity III231 is a plurality of cross levers 232 arranged sequentially from top to bottom; the cross lever 232 includes an intersection and four sides, and the four sides are fixed on the inner wall of the cavity III231, and the lengths of the four sides are equal, and the intersection is on the same straight line in the vertical direction, and the four sides of the cross levers do not overlap in the top view of the cavity III231. The buffer tank 1 is a sealed tank body, and the buffer tank 1 includes a buffer tank outlet and a buffer tank reflux port. The steam discharged from the steam supply end 4 enters the swirl atomization section 21 through the pipeline I51. The outlet of the buffer tank 1 is connected to the organic wastewater inlet 213 through the pipeline III53, and the pipeline III53 is provided with a booster pump 6; after the organic wastewater is discharged from the buffer tank 1, it enters the swirl atomization nozzle 212 from the organic wastewater inlet 213 under the action of the booster pump 6, and the organic wastewater is atomized by the swirl atomizer 2121 in the swirl atomization nozzle 2122, and the organic wastewater discharged from the swirl atomization nozzle 2122 is mixed with steam and enters the throttling atomization section 22 and the vortex atomization section 23. Under the action of steam, the organic wastewater is further atomized or vaporized in the throttling atomization section 22 and the vortex atomization section 23, and the atomized or vaporized organic wastewater and steam are discharged from the vortex atomization section 23;

[0094] The steam and organic wastewater discharged from the vortex atomization section enter the gasifier from the burner via pipeline II52.

[0095] During use, the mixer 2 can atomize the organic wastewater into droplets with a particle size of less than or equal to 50 μm. As the amount of steam added increases, the droplet diameter gradually decreases. When the amount of steam is sufficient, the droplets can be completely vaporized. The aerosol feed has little effect on the flow field in the gasifier, and can form a low-temperature gas film area at the burner head, extending the service life of the burner. Pure gas phase feed has the best effect.

[0096] The pipeline III53 is also provided with a flow regulating valve 17 and a cut-off valve 18, and the flow regulating valve 17 is located between the increasing pump 6 and the mixer 2; the cut-off valve 18 is located between the flow regulating valve 18 and the mixer 2. The buffer tank 1 is connected to the increasing pump 6 through the pipeline IV54, and the pipeline IV54 is provided with a cut-off valve 29. The buffer tank 1 includes a pressure regulating valve 11 and a pressure regulating valve 2 12. The buffer tank 1 also includes a safety valve 13 and a cut-off valve 3 14. The pipeline I51 is also provided with a flow control valve 2 10 and a cut-off valve 4 101.

[0097] The feeding system of the organic wastewater treatment device in this embodiment includes the following steps during operation:

[0098] Step 1: Steam from the steam supply end enters the swirl atomization section, and the organic wastewater enters the swirl atomization nozzle from the organic wastewater inlet, and is sprayed out after the first atomization by the swirl atomization nozzle;

[0099] Step 2: The organic wastewater sprayed from the swirl atomization nozzle and the steam enter the throttling atomization section together. In the throttling atomization section, the organic wastewater continues to be atomized and is mixed with the steam to form aerosol I, which is discharged from the throttling atomization section;

[0100] Step 3: Aerosol I enters the vortex atomization section, and the organic wastewater in the aerosol continues to be atomized in the vortex atomization section. The atomized organic wastewater and steam form aerosol II, which is discharged from the vortex atomization section and enters the gasifier through the burner.

[0101] The organic wastewater enters the gasifier through the integrated burner start-up flow channel.

[0102] The maximum flow rate of organic wastewater addition is determined by the amount of coal fed into the gasifier. The mass ratio of the organic wastewater entering the gasifier to the mass of the coal fed into the gasifier (dry basis) is less than or equal to 1:5. There is no minimum flow rate limit for the addition of organic wastewater. Even when the addition amount is 0, the organic wastewater addition system can be switched to self-circulation operation or shut down, and its operation can be independent of the gasifier system.

[0103] To ensure the atomization effect, a minimum ratio is set between the amount of steam added and the amount of organic wastewater added. The amount of steam used per ton of organic wastewater is not less than 20m3. 3 , and the steam usage is not less than 100m 3 / h, used to protect the burner flow path and burner head. That is, when the amount of organic wastewater is 1 ton, in order to protect the burner flow path and burner head, the amount of steam used cannot be less than 100m 3 / h.

[0104] Steam is selected as the atomization power source, and the temperature of the organic wastewater discharged from the vortex atomization section is controlled by adjusting the flow of the steam flow regulating valve 2. High-temperature feed can not only reduce the stress on the burner, but also reduce the specific oxygen consumption of the device.

[0105] In step 1, the flow rate of the organic wastewater in the buffer tank is controlled by flow regulating valve 1 during the process of introducing the organic wastewater into the mixer.

[0106] The instantaneous flow of the organic wastewater source fluctuates greatly and is unstable. The fluctuation of the instantaneous flow of the organic wastewater source can be coped with by storing it in a buffer tank. During the feeding process, the flow value of the organic wastewater flow regulating valve 1 is set to the average flow of the organic wastewater during the long-term operation.

[0107] The organic wastewater in the buffer tank is pressurized by the wastewater booster pump to a pressure higher than the gasifier by 0.5MPa; the pressurized organic wastewater enters the mixer through the flow control valve 1. The transportation of organic wastewater mainly relies on the booster pump to pressurize the wastewater to a pressure higher than the gasifier by 0.5MPa, so that it has enough power to overcome the resistance of the flow control valve 1 and the mixer and then enter the gasifier.

[0108] After the feeding system of the organic wastewater treatment device is started, first close the shut-off valve one, open the shut-off valve two, and the booster pump controls the organic wastewater to flow back to the buffer tank. After the outlet pressure of the booster pump is stable, open the shut-off valve one, close the shut-off valve two, and the booster pump controls the organic wastewater to enter the mixer.

[0109] Before closing the feeding system of the organic wastewater treatment device, first close the cut-off valve 1, then close the adding pump, so that the organic wastewater adding system can operate independently of the gasifier system, so that the wastewater can be used in the start-up and shutdown conditions.

[0110] When the upstream wastewater flow is low and the liquid level in the organic wastewater buffer tank is also low, the shut-off valve 1 and shut-off valve 2 can be opened to allow part of the wastewater at the outlet of the wastewater booster pump to flow back into the buffer tank, and the flow regulating valve 1 can be closed at the same time to achieve stable operation of the device under the condition of adding organic wastewater at a small flow rate.

[0111] During the reaction process, the pressure in the buffer tank is controlled by adjusting the pressure regulating valve 1 and the pressure regulating valve 2.

[0112] Whether the organic wastewater flows into the buffer tank is controlled by cut-off valve 4.

[0113] The organic wastewater from upstream enters the buffer tank. The pressure inside the buffer tank is about 0.5MPag and the temperature is room temperature. When the flow rate of upstream organic wastewater is low or the liquid level in the organic wastewater buffer tank is high, close the shut-off valve 3 to stop the organic wastewater from entering the buffer tank.

[0114] The buffer tank uses nitrogen to control the pressure inside the tank during use. Low-pressure nitrogen enters the buffer tank through pressure regulating valve 1. When the pressure inside the tank is too high, the gas in the buffer tank is released to the VOCs (volatile organic compounds) treatment system or flare through pressure regulating valve 2;

[0115] The safety of the buffer tank is ensured by the automatic pressure relief function of the safety valve.

[0116] The storage of organic wastewater mainly relies on buffer tanks to cope with the fluctuations in upstream organic wastewater flow, while low-pressure nitrogen sealing is used to reduce the volatilization of organic wastewater.

[0117] Example 3

[0118] The organic wastewater is sprayed into the gasifier for treatment using the feeding system of the organic wastewater treatment device in Example 2.

[0119] Comparative Example 1

[0120] Comparative Example 1 adopts the gasifier feeding process in patent application CN113266836A to feed the organic wastewater into the gasifier for treatment.

[0121] In Example 3 and Comparative Example 1, the dry coal feeding amount is 62.5 t / h, the organic wastewater is vinyl acetate, and the addition amount is 5 t / h. In Example 3, the gasification steam flow rate is 10 t / h, the pressure is 5.5 MPaG, and the temperature is 400°C. In Comparative Example 1, the organic wastewater is fed at room temperature (25°C); the reaction pressure of the gasifier is set to 4.0 MPaG. The temperature field in the gasifier is simulated by CFD (Computational Fluid Dynamics) simulation technology (Fluent), and the process flow simulation software (ASPEN HYSYS) is used to calculate the carbon conversion rate in the gasifier. The results are shown in Table 1.

[0122] Table 1 Temperature and carbon conversion rate in gasifier

[0123] Process No organic wastewater added Example 3 Comparative Example 1 Gasifier temperature (℃) 1819 1752 1685 Carbon conversion rate within gasification rate (%) 99.01 98.42 96.58

[0124] The results of simulating the temperature field in the gasifier are shown in Figure 2. Figure 2 The color depth in the figure indicates the temperature. The darker the color, the higher the temperature. Figure 2It can be seen that when the system of the prior art is used to add organic wastewater to the gasifier in Comparative Example 1, the high temperature zone in the gasifier is significantly reduced, and the low temperature zone has a significant downward shift effect. When the system of Example 2 is used to add organic wastewater to the gasifier in Example 3, the temperature field in the furnace is less affected. When the system of the present invention is used to add organic wastewater to the gasifier, the conversion rate of carbon in the organic wastewater can still be maintained at a high level.

[0125] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein, on the contrary, the present invention can be extended to all other methods and applications with the same functions.

Claims

1. A feeding system for an organic wastewater treatment device, characterized in that: The device for treating organic wastewater is a gasifier, The feeding system comprises: a mixer, a steam supply end, a burner and a pipeline; According to the flow direction of steam in the mixer, the mixer comprises a swirl atomization section, a throttling atomization section and a vortex atomization section in sequence, and the swirl atomization section, the throttling atomization section and the vortex atomization section are connected; The swirl atomization section is a cavity I, a swirl atomization nozzle is arranged inside the cavity I, an organic wastewater inlet is arranged in the cavity I, and the organic wastewater inlet is connected to the swirl atomization nozzle; a swirl atomizer is arranged inside the swirl atomization nozzle; The throttling atomization section is a cavity II, and the cavity II includes an upper section and a lower section, the upper section is a diameter-reducing section, and the lower section is a diameter-expanding section; The vortex atomization section is cavity III, and a structure for generating vortex is arranged inside cavity III; The steam discharged from the steam supply end enters the swirl atomization section through pipeline I, and the organic wastewater enters the swirl atomization nozzle through the organic wastewater inlet. The steam and the organic wastewater sprayed from the swirl atomization nozzle are mixed, and then pass through the throttling atomization section and the vortex atomization section in sequence, and are discharged from the vortex atomization section; the steam discharged from the vortex atomization section and the organic wastewater enter the gasifier from the burner through pipeline II.

2. The feeding system of the organic wastewater treatment device according to claim 1, characterized in that: The structure for generating vortex is a plurality of cross levers arranged in sequence from top to bottom inside cavity III; preferably, the cross lever includes an intersection point and four sides, the four sides are arranged in cavity III, the four sides are equal in length, the intersection point is on the same straight line in the vertical direction, and the four sides of the plurality of cross levers do not overlap in the bottom view of cavity III.

3. The feeding system of the organic wastewater treatment device according to claim 1 or 2, characterized in that: The feeding system further comprises a buffer tank, in which organic wastewater is stored. The buffer tank comprises a buffer tank outlet and a buffer tank reflux port, and the buffer tank outlet is connected to the organic wastewater inlet via a pipeline III.

4. The feeding system of the organic wastewater treatment device according to claim 3, characterized in that: The feeding system further comprises a booster pump, which is arranged in pipeline III and is located between the buffer tank and the mixer.

5. The feeding system of the organic wastewater treatment device according to claim 4, characterized in that: The pipeline III is also provided with a flow regulating valve 1 and a cut-off valve 1, the flow regulating valve 1 is located between the increasing pump and the mixer; the cut-off valve 1 is located between the flow regulating valve 1 and the mixer; and / or the buffer tank reflux port and the increasing pump are connected through a pipeline IV, and the pipeline IV is provided with a cut-off valve 2.

6. The feeding system of the organic wastewater treatment device according to claim 5, characterized in that: The buffer tank includes a first pressure regulating valve and a second pressure regulating valve; and / or, the buffer tank also includes a safety valve and a third cut-off valve.

7. The feeding system of the organic wastewater treatment device according to claim 6, characterized in that: Pipeline I is provided with flow regulating valve 2 and cut-off valve 4.

8. A feeding process for an organic wastewater treatment device, characterized in that: The feeding system of the organic wastewater treatment device according to any one of claims 1 to 7 comprises the following steps: Step 1: Steam from the steam supply end enters the cyclone atomization section, and organic wastewater enters the cyclone atomization nozzle from the organic wastewater inlet. The organic wastewater is atomized by the cyclone atomization nozzle and then sprayed out; Step 2: The organic wastewater sprayed from the swirl atomization nozzle and the steam enter the throttling atomization section together. In the throttling atomization section, the organic wastewater continues to be atomized and is mixed with the steam to form aerosol I, which is discharged from the throttling atomization section; Step 3: Aerosol I enters the vortex atomization section, and the organic wastewater in the aerosol I continues to be atomized in the vortex atomization section. The atomized organic wastewater and steam form aerosol II, which is discharged from the vortex atomization section and enters the gasifier through the burner.

9. The feeding process of the organic wastewater treatment device according to claim 8, characterized in that: In step one, the organic wastewater is collected by the buffer tank and then discharged from the buffer tank outlet, and the organic wastewater discharged from the buffer tank outlet enters the swirl atomization section; preferably, the organic wastewater discharged from the buffer tank outlet enters the swirl atomization section under the action of the booster pump; and / or, the flow rate of the organic wastewater discharged from the buffer tank outlet is controlled by a flow regulating valve during the process of entering the swirl atomization section; preferably, the flow rate of the organic wastewater discharged from the buffer tank outlet is 0-35t / h, and the dry mass ratio of the mass of the organic wastewater entering the gasifier to the amount of coal fed into the gasifier is less than or equal to 1:

5.

10. The feeding process of the organic wastewater treatment device according to claim 9, characterized in that: The amount of steam used per ton of organic wastewater is not less than 20m 3 .

11. The feeding process of the organic wastewater treatment device according to claim 10, characterized in that: The steam flow rate is greater than or equal to 100m 3 / h.

12. The feeding process of the organic wastewater treatment device according to claim 11, characterized in that: After the feeding system is started, first close the shut-off valve 1, open the shut-off valve 2, and the booster pump controls the organic wastewater to flow back to the buffer tank. After the outlet pressure of the booster pump is stable, open the shut-off valve 1, close the shut-off valve 2, and the booster pump controls the organic wastewater to enter the swirl atomization section; and / or, before closing the feeding system, first close the shut-off valve 1, and then close the booster pump.

13. The feeding process of the organic wastewater treatment device according to claim 12, characterized in that: During the reaction process, the pressure in the buffer tank is controlled by pressure regulating valve 1 and pressure regulating valve 2; and / or, whether the organic wastewater flows into the buffer tank is controlled by cut-off valve 3; and / or, the safety of the buffer tank is ensured by the automatic pressure relief function of the safety valve; and / or, the flow rate of steam entering the mixer is controlled by adjusting flow regulating valve 2; and / or, whether the steam enters the vortex atomization section is controlled by cut-off valve 4.

14. An application of the feeding system of the organic wastewater treatment device described in any one of claims 1 to 7 or the feeding process of the organic wastewater treatment device described in any one of claims 8 to 13 in treating organic wastewater, wherein the organic wastewater is organic wastewater generated by a coal chemical plant or organic wastewater generated by a petrochemical plant, and preferably, the organic wastewater is one of organic wastewater generated by an MTO plant, organic wastewater generated by a PDH plant and organic wastewater generated by an EVA plant.

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