Method and system for treating refinery catalytic gas caustic sludge

Abstract

The present application relates to the field of chemical production process, disclose a kind of treatment method and system of oil refining catalytic gas alkali residue, the method comprises: (1) oil refining catalytic gas alkali residue is premixed with ethylene waste lye, obtain first mixture;(2) the first mixture is cyclone mixed with air, obtain second mixture;(3) the second mixture is wet oxidation reaction, and the obtained oxidation reaction product is gas-liquid separation, obtain waste water and waste gas.The sulfide content in the product after oxidation reaction treatment can be reduced to less than 9×10 ‑5 wt%, which is beneficial for the stable operation of subsequent biochemical system in wastewater treatment plant;The heat generated by sulfide oxidation reaction is fully utilized, and the energy consumption of the reaction device is saved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of chemical production process, in particular to a treatment method and system of oil refining catalytic gas alkali residue. BACKGROUND

[0002] The secondary processing of crude oil is a production and processing technology that takes heavy distillate oil (straight-run wax oil, coking wax oil, atmospheric heavy oil, vacuum residue, deasphalted oil, etc.) as raw material, adopts fluidization technology, contacts the raw oil with high-temperature catalyst at a certain temperature and pressure, and a series of chemical reactions occur, thereby converting the raw material into light oil products. The main products are gasoline, light diesel oil and liquefied gas. Among them, the catalytic liquefied gas contains sulfur components (mainly hydrogen sulfide, as well as methyl mercaptan, ethyl mercaptan, etc.), carbon dioxide, etc. The liquefied gas is washed with sodium hydroxide solution, and in the washing process, sodium hydroxide reacts with sulfur components, carbon dioxide, etc. to generate sulfides and carbonates that dissolve in waste alkali liquor, thereby removing acidic gases from the liquefied gas and obtaining a byproduct catalytic gas alkali residue.

[0003] At present, there are two main treatment methods for catalytic gas alkali residue in China; one is moderate wet oxidation (WAO), the reaction temperature is about 180℃, the pressure is about 3MPa, and the sulfide after reaction is about 100mg / L. This method has the problems of incomplete reaction and high sulfide, which will cause difficulties in the stable operation of the subsequent biochemical system of the wastewater field; the second is a special biological treatment method, which uses special bacteria to biologically pretreat the waste alkali liquor, and the treatment efficiency is relatively high, but the waste alkali liquor needs to be diluted in a large amount before entering the biochemical system, and hydrogen sulfide gas will be generated during the dilution and pH adjustment process, causing air pollution.

[0004] The oil refining catalytic gas alkali residue contains a high concentration of sodium sulfide and mercaptan organic matter, and the current "moderate wet oxidation (WAO)" and "special biological treatment method" have obvious drawbacks, and the process discharge sulfide concentration is high, which causes difficulties in the stable operation of the subsequent biochemical system of the wastewater field.

[0005] Therefore, it is of great significance to effectively and low-costly treat the oil refining catalytic gas alkali residue. SUMMARY

[0006] In view of the problem that the existing oil refining catalytic gas alkali residue treatment process has incomplete conversion of sulfides, resulting in high sulfide concentration of the discharge, the present application provides a treatment method and system of oil refining catalytic gas alkali residue.

[0007] In order to achieve the above-mentioned purpose, the first aspect of the present application provides a treatment method of oil refining catalytic gas alkali residue, which comprises:

[0008] (1) Pre-mixing the oil refining catalytic gas alkali residue with ethylene waste alkali liquor to obtain a first mixture;

[0009] (2) the first mixture is mixed with air by cyclone to obtain a second mixture;

[0010] (3) the second mixture is subjected to wet oxidation reaction, and the oxidation reaction product obtained is subjected to gas-liquid separation to obtain waste water and waste gas.

[0011] The second aspect of the present application provides a treatment system for oil refining catalytic gas caustic residue, which comprises a mixing feed unit A, an oxidation reaction unit B and a product separation unit C connected in sequence; wherein,

[0012] The mixing feed unit A is used for pre-mixing the oil refining catalytic gas caustic residue with ethylene waste lye, and mixing the obtained first mixture with air by cyclone to obtain a second mixture;

[0013] The oxidation reaction unit B is used for subjecting the second mixture to wet oxidation reaction to obtain an oxidation reaction product;

[0014] The product separation unit C is used for subjecting the oxidation reaction product to gas-liquid separation to obtain waste water and waste gas.

[0015] Through the above technical solution, the present application has the following beneficial effects:

[0016] (1) By mixing the oil refining catalytic gas caustic residue with ethylene waste lye at a specific ratio for wet oxidation, more complete conversion of sulfides contained in both is realized, and the sulfide content in the product after oxidation reaction treatment can be reduced to less than 9×10 -5 wt%, preferably not higher than 4.6×10 -5 wt%, which is beneficial to the stable operation of the subsequent sewage field biochemical system;

[0017] (2) The cyclone mixing method is used to realize the sufficient mixing of raw materials before wet oxidation reaction, and realize more complete oxidation reaction effect;

[0018] (3) The heat released by the oxidation reaction is recycled, which reduces the consumption of heating steam required for maintaining the reaction of the system, and saves the cost. BRIEF DESCRIPTION OF DRAWINGS

[0019] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, and together with the specific embodiments below, serve to explain the present application, but do not constitute a limitation on the present application. In the drawings:

[0020] Figure 1 is a schematic diagram of the treatment system for oil refining catalytic gas caustic residue according to an embodiment of the present application.

[0021] EXPLANATION OF REFERENCE NUMERALS

[0022] 1, oil refining catalytic gas caustic residue storage tank 2, ethylene waste lye storage tank

[0023] 3. Air compressor 4. Pre-mixer

[0024] 5. Cyclone mixer 6. Reactor

[0025] 61. High-pressure steam line 62. Reactor feed inlet

[0026] 63. Reactor discharge outlet 7. Gas-water separator

[0027] 71. Waste gas discharge line 72. Waste water discharge line

[0028] 8. Oil refining catalytic gas caustic residue feed flow pump 9. Heat exchanger

[0029] 91. Reaction raw material heat exchange feed inlet 92. Reaction raw material heat exchange discharge outlet

[0030] 93. Reaction product heat exchange feed inlet 94. Reaction product heat exchange discharge outlet

[0031] 10. Cooler DETAILED DESCRIPTION

[0032] The endpoints of the ranges and any values disclosed herein are not limited to the precise values recited as the exact dimensions are not critical to the invention. Any numerical value, however, can include any values up to the stated range, value, or limit, and any value within the range, value, or limit, unless the context clearly indicates otherwise. The disclosure of a range or a value includes each possible combination of these values and ranges.

[0033] The first aspect of the present application provides a treatment method of oil refining catalytic gas caustic residue, the method comprising:

[0034] (1) Pre-mixing the oil refining catalytic gas caustic residue with ethylene waste lye to obtain a first mixture;

[0035] (2) Cyclone mixing the first mixture with air to obtain a second mixture;

[0036] (3) Wet oxidation reaction of the second mixture, and gas-liquid separation of the obtained oxidation reaction product to obtain waste water and waste gas.

[0037] According to the present application, the oil refining catalytic gas caustic residue is waste lye produced in the process of washing and removing acid gas by alkali solution from liquefied gas (containing pollutants including hydrogen sulfide, methyl mercaptan, ethyl mercaptan, and carbon dioxide) produced by crude oil processing, and has a high salt concentration and COD concentration.

[0038] According to the present application, the content of sodium sulfide in the oil refining catalytic gas caustic residue is 0.2-5% by weight, the content of sodium carbonate is 1-5% by weight, the content of sodium hydroxide is 2-10% by weight, the content of organic sulfur is 50-2000 mg / L, and the content of oil is 50-1000 mg / L.

[0039] According to the present application, preferably, the content of sodium sulfide in the oil refining catalytic gas caustic residue is 1-2% by weight, the content of sodium carbonate is 1-2% by weight, the content of sodium hydroxide is 2-3% by weight, the content of organic sulfur is 50-1000 mg / L, and the content of oil is 50-200 mg / L.

[0040] According to the present application, the ethylene waste lye is the waste lye produced in the process of removing acid gas in the cracking gas by using alkali washing method in the ethylene device, which contains not only the residual sodium hydroxide not consumed in the alkali washing process, but also the inorganic salts such as sodium sulfide and sodium carbonate generated in the alkali washing process, and various organic components from the cracking gas, and has the characteristics of high concentration of pollutants and violent fluctuation of components. In the present application, the content of sodium sulfide in the ethylene waste lye is 0.2-2% by weight, the content of sodium carbonate is 0.5-2% by weight, the content of sodium hydroxide is 1-3% by weight, the content of organic sulfur is 50-500 mg / L, and the content of oil is 50-1000 mg / L.

[0041] According to the present application, in step (1), the pre-mixing of the oil refining catalytic gas caustic residue and the ethylene waste lye can be carried out by any mixing method, and the present application does not have special limitations thereon, as long as the purpose of mixing the two can be achieved, and a uniform first mixture is obtained. It is particularly important to control the mixing ratio of the oil refining catalytic gas caustic residue and the ethylene waste lye, and preferably, the weight ratio of the oil refining catalytic gas caustic residue to the ethylene waste lye is (0.2-1) : 1, and further preferably (0.3-0.7) : 1.

[0042] According to the present application, in step (2), the air used in the wet oxidation reaction is preferably compressed air treated by compression.

[0043] According to the present application, in step (2), preferably, the volume ratio of the first mixture to air is (0.05-0.2) : 1, and preferably (0.08-0.12) : 1.

[0044] According to the present application, in step (2), the cyclone mixing refers to the uniform mixing of the gas-liquid two-phase raw materials under the action of cyclone shear, which is beneficial to the more thorough oxidation reaction. Preferably, the conditions of the cyclone mixing include that the pressure drop of the second mixture compared to the first mixture is <0.01 MPa.

[0045] According to the present application, in step (2), the air exists in the form of micro-bubbles in the obtained second mixture after the cyclone mixing.

[0046] In the present application, the cyclone mixing makes the average particle size of the air micro-bubbles in the second mixture be 1-8 mm, which is beneficial to the more sufficient distribution of the air in the liquid phase raw material and the realization of the uniform mixing, and promotes the more thorough oxidation reaction. Preferably, the solubility of the air in the second mixture is ≥7.5% by volume.

[0047] In the present application, the average particle size of the air micro-bubbles in the second mixture is obtained by the on-line sample test by a microscope.

[0048] According to the present application, in step (3), the wet oxidation reaction can be carried out in a conventional reactor in the wet oxidation process, and the present application does not have a particular limitation. For the alkaline mixture material in the method of the present application, the conditions of the wet oxidation reaction include: the temperature is 150-350 ℃, preferably 190-220 ℃; the pressure is 2.1-20 MPa, preferably 3-3.2 MPa. Based on the above reaction conditions, using air as the oxidant, the sulfides (referring to the compounds containing S with the valence of -2) and the organic matters contained in the second mixture are subjected to the oxidation reaction, wherein the sulfides are converted into sulfates or sulfites, and the organic matters are partially oxidized and decomposed into carbon dioxide and water or converted into low-molecular organic matters, while releasing the reaction heat, to obtain the high-temperature oxidation reaction product. The oxidation reaction product is a mixture of gas and liquid phases.

[0049] According to the present application, after the wet oxidation reaction, the content of the sulfides in the obtained oxidation reaction product is <9×10 -5 % by weight, which meets the index requirements of the sewage discharge field, and is beneficial to the stable operation of the biochemical system of the sewage field.

[0050] In the present application, the sulfides in the oxidation reaction product refer to the compounds containing S with the valence of -2, such as unconverted Na2S.

[0051] In the present application, the content of the sulfides in the oxidation reaction product is based on the total weight of the oxidation reaction product.

[0052] According to the present application, in step (3), the gas-liquid separation can adopt any method capable of realizing the separation of the gas and liquid phases, and the present application does not have a particular limitation. Preferably, the gas-liquid separation adopts the cyclone separation mode, which can obtain a more sufficient separation effect.

[0053] According to the application, the cyclone separation refers to using cyclone field centrifugal force to reduce the concentration of wastewater entrained by gas in the gas-liquid mixture as much as possible. 3 .

[0054] In the application, the split ratio refers to the ratio of the volume of the dispersed phase (the phase with smaller volume) to the volume of the material at the feeding port before the cyclone separation.

[0055] In the application, the main components of the wastewater include sulfates, sulfites, sodium hydroxide, etc., wherein the content of sulfides (compounds containing S with a valence of -2) has reached the index requirement of the wastewater discharge field; and the main components of the waste gas include volatile organic compounds.

[0056] According to the application, preferably, the method can further include heat exchanging the oxidation reaction product with a second mixture before the gas-liquid separation. By preheating and warming the second mixture through heat exchange, energy consumption of the subsequent wet oxidation reaction can be reduced, and the oxidation reaction product is cooled through heat exchange, which is more conducive to gas-liquid separation.

[0057] The application is aimed at the characteristics of high sulfide concentration and difficult treatment of the oil refining catalytic gas caustic residue. The oil refining catalytic gas caustic residue is mixed with ethylene waste lye at a specific ratio for wet oxidation, so that the content of sulfides in the obtained product after treatment can be reduced to less than 9*10 -5 wt%, preferably not higher than 4.6*10 -5 wt%, which is conducive to the stable operation of the subsequent wastewater field biochemical system. In the treatment method of the application, the wet oxidation reaction is realized by using cyclone mixing to fully mix the raw materials before the wet oxidation reaction, so as to promote the full conversion of sulfides in the oxidation process. In the treatment method of the application, the heat generated by the oxidation reaction can be recycled, so as to reduce the energy consumption required for maintaining the oxidation reaction and save costs.

[0058] The second aspect of the application provides a treatment system for oil refining catalytic gas caustic residue, as shown in Figure 1 the system includes a mixing feeding unit A, an oxidation reaction unit B and a product separation unit C which are sequentially connected; wherein,

[0059] The mixing feeding unit A is used for pre-mixing the oil refining catalytic gas caustic residue with the ethylene waste lye, and performing cyclone mixing of the obtained first mixture with air to obtain a second mixture;

[0060] The oxidation reaction unit B is used for wet oxidation reaction of the second mixture to obtain an oxidation reaction product;

[0061] The product separation unit C is used for gas-liquid separation of the oxidation reaction product, to obtain waste water and waste gas.

[0062] According to the present application, the mixing feeding unit A comprises a set of oil refining catalytic gas caustic residue storage tank 1, ethylene waste caustic liquid storage tank 2, air compressor 3, premixing device 4 and cyclone mixer 5.

[0063] According to the present application, the oil refining catalytic gas caustic residue storage tank 1 and the ethylene waste caustic liquid storage tank 2 are respectively communicated with the premixing device 4.

[0064] According to the present application, the cyclone mixer 5 is communicated with the premixing device 4 and the air compressor 3.

[0065] According to the present application, the oil refining catalytic gas caustic residue storage tank 1 is used for storing the oil refining catalytic gas caustic residue by-produced from the crude oil processing system outside the boundary; the ethylene waste caustic liquid storage tank 2 is used for storing the ethylene waste caustic liquid generated by the caustic washing tower of the ethylene device outside the boundary; the air compressor 3 is used for air pressurization, to provide the power of the oxidant gas source required by the oxidation reaction; the premixing device 4 is used for premixing the oil refining catalytic gas caustic residue with the ethylene waste caustic liquid, to obtain the first mixed material; and the cyclone mixer 5 is used for cyclone mixing of the first mixed material with air, to obtain the second mixed material.

[0066] In the present application, the premixing device 4 can adopt a conventional device for mixing liquid-phase materials, and the present application does not have a particular limitation thereon.

[0067] In the present application, the structure of the cyclone mixer 5 comprises a tangential feeding port, a mixing column segment, a mixing taper and a gradually expanding drainage port, and the gas-liquid two-phase materials are fully mixed through the cyclone shearing force, so that the solubility of air in the obtained second mixed material is ≥7.5% by volume, and the air exists in the form of micro-bubbles (the average particle size of the air micro-bubbles is 1-8 mm), to realize the full and uniform mixing of the gas-liquid two-phase raw materials. The cyclone mixer 5 can be obtained through a conventional commercial channel.

[0068] According to the present application, preferably, the mixing feeding unit A can further comprise an oil refining catalytic gas caustic residue feeding flow pump 8 and a high-pressure feeding pump (not shown in the figure). Figure 1 The oil refining catalytic gas caustic residue feeding flow pump 8 is communicated with the oil refining catalytic gas caustic residue storage tank 1 and the premixing device 4, and is used for controlling the feeding amount and regulating the mixing ratio of the oil refining catalytic gas caustic residue and the ethylene waste caustic liquid. The high-pressure feeding pump is communicated with the premixing device 4 and the cyclone mixer 5, and is used for pressurizing and conveying the first mixed material to the cyclone mixer 5 for cyclone mixing with air.

[0069] According to the present application, the oxidation reaction unit B comprises a reactor 6 in communication with the cyclone mixer 5. The reactor 6 is in communication with a high-pressure steam pipeline 61. The high-pressure steam pipeline 61 is used to continuously provide high-pressure hot steam to the reactor 6 to maintain the temperature required for the oxidation reaction.

[0070] In the present application, the reactor 6 can adopt a conventional reactor in the wet oxidation process. The second mixture from the mixed feed unit A enters the reactor 6 through a reactor feed port 62, and under the conditions of medium temperature and medium-high pressure, the sulfides (referring to the compounds containing S with a valence of -2) and organic matter contained in the second mixture are subjected to oxidation reaction using air as the oxidant, wherein the sulfides are converted into sulfates or sulfites, and the organic matter is partially oxidized and decomposed into carbon dioxide and water or converted into low-molecular organic matter, while releasing reaction heat, to obtain high-temperature oxidation reaction products (wherein the content of sulfides < 9 x 10 -5 wt. %), which are led out from a reactor discharge port 63. The oxidation reaction products are a mixture of gas and liquid phases.

[0071] According to the present application, the product separation unit C comprises a gas-water separator 7 in communication with the reactor 6. The oxidation reaction products from the oxidation reaction unit B are subjected to gas-liquid separation in the gas-water separator 7, and the separated waste water meets the index requirements of the sewage discharge field, is led out from a waste water discharge pipeline 72 at the bottom of the gas-water separator 7, and is sent to a sewage field biochemical system outside the boundary area for further treatment; the separated waste gas is led out from a waste gas discharge pipeline 71 at the top of the gas-water separator 7, and is preferably sent to a incinerator outside the boundary area for incineration treatment.

[0072] According to the present application, preferably, the gas-water separator 7 is a cyclone separator, which includes a tangential feed port, a column-cone mixing and separation section, a gas discharge port and a liquid discharge port in its structure, and can obtain more sufficient gas-liquid separation effect through the centrifugal force in the cyclone field, so that the carrying amount of waste water in the separated waste gas < 20 mg / m 3 .

[0073] According to the present application, preferably, the product separation unit C can further comprise a cooler 10. The cooler 10 is in communication with the reactor 6 and the gas-water separator 7, and is used to cool the oxidation reaction products before the gas-liquid separation, which is beneficial to obtain better separation effect.

[0074] According to the present application, preferably, the oxidation reaction unit B further comprises a heat exchanger 9, which is in communication with the cyclone mixer 5, the reactor 6 and the gas-water separator 7, and is used to exchange heat between the oxidation reaction products and the second mixture before the gas-liquid separation.

[0075] In the present application, specifically, the heat exchanger 9 is provided with a reaction raw material heat exchange feed port 91, a reaction raw material heat exchange discharge port 92, a reaction product heat exchange feed port 93 and a reaction product heat exchange discharge port 94; wherein the reaction raw material heat exchange feed port 91 is communicated with the cyclone mixer 5; the reaction raw material heat exchange discharge port 92 is communicated with the reactor feed port 62 of the reactor 6; the reaction product heat exchange feed port 93 is communicated with the reactor discharge port 63 of the reactor 6; and the reaction product heat exchange discharge port 94 is communicated with the gas-water separator 7, preferably communicated with the gas-water separator 7 through the cooler 10. The second mixed material from the mixed feed unit A enters the heat exchanger 9 through the reaction raw material heat exchange feed port 91, exchanges heat with the high-temperature oxidation reaction product from the reactor discharge port 63 and entering the heat exchanger 9 through the reaction product heat exchange feed port 93, and leaves the heat exchanger 9 through the reaction raw material heat exchange discharge port 92, and then enters the reactor 6 through the reactor feed port 62 for oxidation reaction; the oxidation reaction product is cooled after heat exchange, and then enters the product separation unit C. By providing the heat exchanger 9, the operation energy consumption of the oxidation reaction unit B can be saved, the consumption of high-pressure hot steam can be greatly reduced, and the gas-liquid separation of the oxidation reaction product in the product separation unit C is facilitated.

[0076] The following will be described in combination with Figure 1 The present application provides a method for treating oil refining catalytic gas caustic sludge by using the oil refining catalytic gas caustic sludge treatment system.

[0077] (1) In the mixed feed unit A, the oil refining catalytic gas caustic sludge in the oil refining catalytic gas caustic sludge storage tank 1 is pressurized by the oil refining catalytic gas caustic sludge feed flow pump 8, and the ethylene waste lye from the ethylene waste lye storage tank 2 is pre-mixed in the pre-mixer 4 (the weight ratio of the oil refining catalytic gas caustic sludge to the ethylene waste lye is 0.2-1:1), to obtain a first mixed material;

[0078] (2) The first mixed material is pressurized by a high-pressure feed pump, and enters the cyclone mixer 5 to be mixed with air from the air compressor 3 (the volume ratio of the first mixed material to the air is 0.05-0.2:1; the pressure drop of the second mixed material compared with the first mixed material is <0.01 MPa), to obtain a second mixed material (in the second mixed material, the average particle size of the air micro-bubbles is 1-8 mm, and the solubility of the air is ≥7.5% by volume);

[0079] (3-1) In the oxidation reaction unit B, the second mixture enters the reaction raw material heat exchange inlet 91 of the heat exchanger 9, exchanges heat with the high-temperature oxidation reaction product (190-220 °C) from the reactor outlet 63 and entering the reaction product heat exchange inlet 93 of the heat exchanger 9, after heat exchange, the second mixture is preheated to 140-170 °C and leaves the reaction raw material heat exchange outlet 92 of the heat exchanger 9 and enters the reactor 6; after heat exchange, the oxidation reaction product is cooled to 65-120 °C and is led out by the reaction product heat exchange outlet 94 and enters the product separation unit C;

[0080] The high-pressure steam from the high-pressure steam pipeline 61 is transported to the reactor 6 to continue heating the second mixture, and the second mixture is subjected to wet oxidation reaction at 150-350 °C and 2.1-20 MPa in the reactor 6, and the obtained high-temperature oxidation reaction product (sulfide content <9×10 -5 wt%) is led out by the reactor outlet 63 and enters the heat exchanger 9 for the above heat exchange and cooling process;

[0081] (3-2) In the product separation unit C, the heat-exchanged and cooled oxidation reaction product is further cooled to 30-65 °C by the cooler 10, and then enters the gas-water separator 7 for gas-liquid separation, the obtained waste gas is discharged by the waste gas discharge pipeline 71 and sent to the incinerator outside the boundary area for incineration treatment; the obtained waste water is discharged by the waste water discharge pipeline 72 to the outside of the boundary area and then enters the sewage field biochemical system for further treatment.

[0082] The application will be described in detail below by examples. In the following examples and comparative examples,

[0083] The main components and contents of the ethylene waste lye used are shown in Table 1.

[0084] Table 1

[0085] Component Content NaOH 2.5 wt.% Na2S 1.2 wt.% Na2CO3 1 wt.% Organic sulfur 100 mg / L Oil fraction 200 mg / L

[0086] The main components and contents of the oil refining catalytic gas lye residue used are shown in Table 2.

[0087] Table 2

[0088] Component Content NaOH 2 wt.% Na2S 1.2 wt.% Na2CO3 1.5 wt.% Organic sulfur 150 mg / L Oil fraction 300 mg / L

[0089] Example 1

[0090] (1) In the mixed feed unit A, the oil refining catalytic gas lye residue in the oil refining catalytic gas lye residue storage tank 1 is pressurized to 0.6 MPa by the oil refining catalytic gas lye residue feed flow pump 8, and the ethylene waste lye from the ethylene waste lye storage tank 2 enters the premixer 4 for premixing (the weight ratio of oil refining catalytic gas lye residue to ethylene waste lye is 0.3:1), to obtain the first mixture;

[0091] (2) The first mixture is pressurized to 4.5 MPa by a high-pressure feed pump and enters a cyclone mixer 5 to be mixed with air from an air compressor 3 (volume ratio of the first mixture to air: 0.1:1; pressure drop of the second mixture compared with the first mixture: 0.008 MPa), to obtain a second mixture (in the second mixture, the average particle size of air micro-bubbles is 2 mm, and the solubility of air is 10% by volume);

[0092] (3-1) In the oxidation reaction unit B, the second mixture enters the reaction material heat exchange feed port 91 of the heat exchanger 9, exchanges heat with the high-temperature oxidation reaction product (200°C) from the reactor discharge port 63 and entering the reaction product heat exchange feed port 93 of the heat exchanger 9, after heat exchange, the second mixture is preheated to 160°C and leaves the reaction material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after heat exchange, the oxidation reaction product is cooled to 120°C and is led out from the reaction product heat exchange discharge port 94 and enters the product separation unit C;

[0093] The high-pressure steam from the high-pressure steam pipeline 61 is transported to the reactor 6 to continue heating and warming the second mixture, and the second mixture is subjected to wet oxidation reaction at 200°C and 3.2 MPa in the reactor 6, and the obtained high-temperature oxidation reaction product (the content of sulfides is shown in Table 3) is led out from the reactor discharge port 63 and enters the heat exchanger 9 for the above-mentioned heat exchange and cooling process;

[0094] (3-2) In the product separation unit C, the heat-exchanged and cooled oxidation reaction product is further cooled to 65°C by the cooler 10, and then enters the gas-water separator 7 (a cyclone separator) for gas-liquid separation (separation condition: split ratio is 6%), the obtained waste gas is discharged from the waste gas discharge pipeline 71 (the carrying amount of waste water in the waste gas is 15 mg / m 3 ), and is sent to a burning furnace outside the boundary area for burning treatment; the obtained waste water is discharged from the waste water discharge pipeline 72 to the outside of the boundary area and is subsequently subjected to further treatment in a sewage field biochemical system.

[0095] Example 2

[0096] (1) In the mixed feed unit A, the oil refining catalytic gas caustic sludge in the oil refining catalytic gas caustic sludge storage tank 1 is pressurized to 0.6 MPa by the oil refining catalytic gas caustic sludge feed flow pump 8, and enters the premixer 4 with the ethylene waste lye from the ethylene waste lye storage tank 2 to be premixed (weight ratio of the oil refining catalytic gas caustic sludge to the ethylene waste lye: 0.6:1), to obtain a first mixture;

[0097] (2) The first mixture is pressurized to 4.5 MPa by a high-pressure feed pump and enters a cyclone mixer 5 to be mixed with air from an air compressor 3 (volume ratio of the first mixture to air: 0.11:1; pressure drop of the second mixture compared to the first mixture: 0.008 MPa), to obtain a second mixture (in the second mixture, the average particle size of air micro-bubbles is 4 mm, and the solubility of air is 11% by volume);

[0098] (3-1) In the oxidation reaction unit B, the second mixture enters the reaction raw material heat exchange feed port 91 of the heat exchanger 9, exchanges heat with the high-temperature oxidation reaction product (200°C) from the reactor discharge port 63 and entering the reaction product heat exchange feed port 93 of the heat exchanger 9, after heat exchange, the second mixture is preheated to 160°C and leaves the reaction raw material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after heat exchange, the oxidation reaction product is cooled to 120°C and is led out from the reaction product heat exchange discharge port 94 and enters the product separation unit C;

[0099] The high-pressure steam from the high-pressure steam pipeline 61 is transported to the reactor 6 to continue heating and warming the second mixture, and the second mixture is subjected to wet oxidation reaction at 200°C and 3.2 MPa in the reactor 6, to obtain a high-temperature oxidation reaction product (the content of sulfides is shown in Table 3) which is led out from the reactor discharge port 63 and enters the heat exchanger 9 for the above-mentioned heat exchange and cooling process;

[0100] (3-2) In the product separation unit C, the heat-exchanged and cooled oxidation reaction product is further cooled to 65°C by the cooler 10, and then enters the gas-water separator 7 (a cyclone separator) for gas-liquid separation (separation conditions: split ratio of 5%), the obtained waste gas is discharged from the waste gas discharge pipeline 71 (the carrying amount of waste water in the waste gas is 12 mg / m 3 ), and is sent to a burning furnace outside the boundary area for burning treatment; the obtained waste water is discharged from the waste water discharge pipeline 72 to the outside of the boundary area and is subsequently subjected to further treatment in a sewage field biochemical system.

[0101] Example 3

[0102] (1) In the mixed feed unit A, the oil refining catalytic gas caustic sludge in the oil refining catalytic gas caustic sludge storage tank 1 is pressurized to 0.6 MPa by the oil refining catalytic gas caustic sludge feed flow pump 8, and enters the premixer 4 with the ethylene waste lye from the ethylene waste lye storage tank 2 to be premixed (weight ratio of the oil refining catalytic gas caustic sludge to the ethylene waste lye: 1:1), to obtain a first mixture;

[0103] (2) The first mixture is pressurized to 4.5 MPa by a high-pressure feed pump and enters a cyclone mixer 5 to be mixed with air from an air compressor 3 (volume ratio of the first mixture to air: 0.11:1; pressure drop of the second mixture compared to the first mixture: 0.008 MPa), to obtain a second mixture (in the second mixture, the average particle size of air micro-bubbles is 4 mm, and the solubility of air is 11% by volume);

[0104] (3-1) In the oxidation reaction unit B, the second mixture enters the reaction raw material heat exchange feed port 91 of the heat exchanger 9, exchanges heat with the high-temperature oxidation reaction product (200°C) from the reactor discharge port 63 and entering the reaction product heat exchange feed port 93 of the heat exchanger 9, after heat exchange, the second mixture is preheated to 160°C and leaves the reaction raw material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after heat exchange, the oxidation reaction product is cooled to 120°C and is led out from the reaction product heat exchange discharge port 94 and enters the product separation unit C;

[0105] The high-pressure steam from the high-pressure steam pipeline 61 is transported to the reactor 6 to continue heating and warming the second mixture, and the second mixture is subjected to wet oxidation reaction at 200°C and 3.2 MPa in the reactor 6, to obtain a high-temperature oxidation reaction product (the content of sulfides is shown in Table 3) which is led out from the reactor discharge port 63 and enters the heat exchanger 9 for the above-mentioned heat exchange and cooling process;

[0106] (3-2) In the product separation unit C, the heat-exchanged and cooled oxidation reaction product is further cooled to 65°C by the cooler 10, and then enters the gas-water separator 7 (a cyclone separator) for gas-liquid separation (separation conditions: split ratio of 5%), the obtained waste gas is discharged from the waste gas discharge pipeline 71 (the carrying amount of waste water in the waste gas is 12 mg / m 3 ), and is sent to a burning furnace outside the boundary area for burning treatment; the obtained waste water is discharged from the waste water discharge pipeline 72 to the outside of the boundary area and is subsequently subjected to further treatment in a sewage field biochemical system.

[0107] Example 4

[0108] (1) In the mixed feed unit A, the oil refining catalytic gas caustic sludge in the oil refining catalytic gas caustic sludge storage tank 1 is pressurized to 0.6 MPa by the oil refining catalytic gas caustic sludge feed flow pump 8, and enters the premixer 4 to be premixed with the ethylene waste lye from the ethylene waste lye storage tank 2 (weight ratio of the oil refining catalytic gas caustic sludge to the ethylene waste lye: 0.6:1), to obtain a first mixture;

[0109] (2) The first mixture is pressurized to 4.5 MPa by a high-pressure feed pump and enters a cyclone mixer 5 to be mixed with air from an air compressor 3 (volume ratio of the first mixture to air: 0.11:1; pressure drop of the second mixture compared to the first mixture: 0.015 MPa), to obtain a second mixture (in the second mixture, the average particle size of air micro-bubbles is 12 mm, and the solubility of air is 7% by volume);

[0110] (3-1) In the oxidation reaction unit B, the second mixture enters the reaction raw material heat exchange feed port 91 of the heat exchanger 9, exchanges heat with the high-temperature oxidation reaction product (200°C) from the reactor discharge port 63 and entering the reaction product heat exchange feed port 93 of the heat exchanger 9, after heat exchange, the second mixture is preheated to 160°C and leaves the reaction raw material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after heat exchange, the oxidation reaction product is cooled to 120°C and is led out from the reaction product heat exchange discharge port 94 and enters the product separation unit C;

[0111] The high-pressure steam from the high-pressure steam pipeline 61 is transported to the reactor 6 to continue heating and warming the second mixture, and the second mixture is subjected to wet oxidation reaction at 200°C and 3.2 MPa in the reactor 6, to obtain a high-temperature oxidation reaction product (the content of sulfides is shown in Table 3) which is led out from the reactor discharge port 63 and enters the heat exchanger 9 for the above-mentioned heat exchange and cooling process;

[0112] (3-2) In the product separation unit C, the heat-exchanged and cooled oxidation reaction product is further cooled to 65°C by the cooler 10, and then enters the gas-water separator 7 (a cyclone separator) for gas-liquid separation (separation conditions: split ratio of 5%); the obtained waste gas is discharged from the waste gas discharge pipeline 71 (the carrying amount of waste water in the waste gas is 12 mg / m 3 ), and is sent to a burning furnace outside the boundary area for burning treatment; the obtained waste water is discharged from the waste water discharge pipeline 72 to the outside of the boundary area and is subsequently subjected to further treatment in a sewage field biochemical system.

[0113] Example 5

[0114] 1) In the mixed feed unit A, the refinery catalytic gas caustic sludge in the refinery catalytic gas caustic sludge storage tank 1 is pressurized to 0.6 MPa by a refinery catalytic gas caustic sludge feed flow pump 8, and enters the premixer 4 with the ethylene waste lye from the ethylene waste lye storage tank 2 to be premixed (weight ratio of the refinery catalytic gas caustic sludge to the ethylene waste lye: 1.5:1), to obtain a first mixture;

[0115] (2) The first mixture is pressurized to 4.5 MPa by a high-pressure feed pump and enters a cyclone mixer 5 to be mixed with air from an air compressor 3 (volume ratio of the first mixture to air: 0.1:1; pressure drop of the second mixture compared with the first mixture: 0.008 MPa) to obtain a second mixture (in the second mixture, the average particle size of air micro-bubbles is 2 mm, and the solubility of air is 10% by volume);

[0116] (3-1) In the oxidation reaction unit B, the second mixture enters the reaction material heat exchange feed port 91 of the heat exchanger 9, exchanges heat with the high-temperature oxidation reaction product (200°C) from the reactor discharge port 63 and entering the reaction product heat exchange feed port 93 of the heat exchanger 9, after heat exchange, the second mixture is preheated to 160°C and leaves the reaction material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after heat exchange, the oxidation reaction product is cooled to 120°C and is led out from the reaction product heat exchange discharge port 94 and enters the product separation unit C;

[0117] The high-pressure steam from the high-pressure steam pipeline 61 is transported to the reactor 6 to continue heating and warming the second mixture, and the second mixture is subjected to wet oxidation reaction at 200°C and 3.2 MPa in the reactor 6 to obtain a high-temperature oxidation reaction product (the content of sulfides is shown in Table 3) which is led out from the reactor discharge port 63 and enters the heat exchanger 9 for the above-mentioned heat exchange and cooling process;

[0118] (3-2) In the product separation unit C, the heat-exchanged and cooled oxidation reaction product is further cooled to 65°C by the cooler 10 and then enters the gas-water separator 7 (a cyclone separator) for gas-liquid separation (separation condition: split ratio of 6%); the obtained waste gas is discharged from the waste gas discharge pipeline 71 (the carrying amount of waste water in the waste gas is 15 mg / m 3 ), and is sent to a burning furnace outside the boundary area for burning treatment; the obtained waste water is discharged from the waste water discharge pipeline 72 to the outside of the boundary area and then enters a sewage field biochemical system for further treatment.

[0119] Comparative Example 1

[0120] According to the method of Example 1, the difference is that the oil refining catalytic gas alkali residue is not pre-mixed with the ethylene waste lye, but is directly used as a raw material to replace the "first mixture" to sequentially perform steps (2), (3-1) and (3-2). Other conditions are the same as those in Example 1.

[0121] The content of sulfides in the obtained high-temperature oxidation reaction product is shown in Table 3.

[0122] Comparative Example 2

[0123] The second mixture was obtained according to the method of Example 1, except that the rotary flow mixer 5 was replaced by a static mixer (in the second mixture, the average particle size of air bubbles was 16 mm, and the solubility of air was 5% by volume). The other conditions were the same as in Example 1.

[0124] The sulfide content in the obtained high-temperature oxidation reaction product is shown in Table 3.

[0125] Table 3

[0126] Oxidation reaction product Sulfide content / wt.% Oxidation reaction product (Example 1) 2.8 x 10 -5 ]] Oxidation reaction product (Example 2) 1.8 x 10 -5 ]]> Oxidation reaction product (Example 3) 4.6 x 10 -5 ]]> Oxidation reaction product (Example 4) 6.4 x 10 -5 ]] Oxidation reaction product (Example 5) 7.4 x 10 -5 ]] Oxidation reaction product (Comparative Example 1) 27.6 x 10 -5 ]]> Oxidation reaction product (Comparative Example 2) 23 x 10 -5 ]]>

[0127] As can be seen from Table 3, by using the treatment method of the oil refining catalytic gas caustic sludge provided by the present application, the oil refining catalytic gas caustic sludge is mixed with ethylene waste lye for wet oxidation, which can realize the full conversion of the sulfides contained in the oil refining catalytic gas caustic sludge, and the sulfide content in the treated product can be reduced to less than 9x10 -5 wt%. Among them, Examples 1-3 control the weight ratio of oil refining catalytic gas caustic sludge to ethylene waste lye in the range of (0.2-1):1, and use suitable rotary flow mixing conditions, which can reduce the sulfide content in the treated product to not higher than 4.6x10 -5 wt%. In particular, Comparative Examples 1-2 do not use the method of the present application, and the sulfide content in the process discharge is significantly high.

[0128] The above describes the preferred embodiments of the present application in detail, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be considered as disclosed by the present application, and all fall within the protection scope of the present application.

Claims

1. A method for treating alkaline residue from oil refining catalytic gas, characterized in that, The method comprises: (1) Pre-mixing oil refining catalytic gas alkali residue and ethylene waste lye to obtain a first mixture; (2) Swirl mixing the first mixture with air to obtain a second mixture; (3) Performing wet oxidation reaction on the second mixture, and performing gas-liquid separation on the obtained oxidation reaction product to obtain waste water and waste gas; The weight ratio of oil refining catalytic gas alkali residue to ethylene waste lye is (0.2-1):1; In the second mixture, air exists in the form of micro-bubbles; the average particle size of air micro-bubbles is 1-8 mm; the solubility of air in the second mixture is ≥7.5% by volume.

2. The method of claim 1, wherein, In the oil refining catalytic gas alkali residue, the content of sodium sulfide is 0.2-5% by weight, the content of sodium carbonate is 1-5% by weight, and the content of sodium hydroxide is 2-10% by weight; And / or, in the oil refining catalytic gas alkali residue, the content of organic sulfur is 50-2000 mg / L; And / or, in the oil refining catalytic gas alkali residue, the content of oil is 50-1000 mg / L.

3. The method of claim 1 or 2, wherein, In the ethylene waste lye, the content of sodium sulfide is 0.2-2% by weight, the content of sodium carbonate is 0.5-2% by weight, and the content of sodium hydroxide is 1-3% by weight; And / or, in the ethylene waste lye, the content of organic sulfur is 50-500 mg / L; And / or, in the ethylene waste lye, the content of oil is 50-1000 mg / L.

4. The method of claim 1 or 2, wherein, In step (1), the weight ratio of oil refining catalytic gas alkali residue to ethylene waste lye is (0.3-0.7):

1.

5. The method of claim 1 or 2, wherein, In step (2), the volume ratio of the first mixture to air is (0.05-0.2):1; And / or, the conditions of the swirl mixing include that the pressure drop of the second mixture compared with the first mixture is <0.01 MPa.

6. The method of claim 5, wherein, In step (2), the volume ratio of the first mixture to air is (0.08-0.12):

1.

7. The method of claim 1 or 2, wherein, In step (3), the conditions of the wet oxidation reaction include that the temperature is 150-350°C, and the pressure is 2.1-20 MPa; and / or, in the oxidation reaction product, the sulfide content is < 9 x 10 -5 wt. %.

8. The method of claim 7, wherein, In step (3), the conditions of the wet oxidation reaction include that the temperature is 190-220°C, and the pressure is 3-3.2 MPa.

9. The method according to claim 1 or 2, wherein, In step (3), the gas-liquid separation adopts the swirl separation mode.

10. The method of claim 9, wherein, The conditions of the swirl separation include that the diversion ratio is <8%; and / or, the waste gas carries < 20 mg / m 3 .

11. The method of claim 1 or 2, wherein, The method further comprises, before the gas-liquid separation, heat exchanging the oxidation reaction product with the second mixture.

12. A system for treating alkaline residue from oil refining catalytic gas, characterized in that, The system comprises, in sequence, a mixed feed unit (A), an oxidation reaction unit (B), and a product separation unit (C); wherein, The mixed feed unit (A) is used for pre-mixing oil refining catalytic gas alkali residue and ethylene waste lye, and swirl mixing the obtained first mixture with air to obtain a second mixture; The oxidation reaction unit (B) is used for performing wet oxidation reaction on the second mixture to obtain an oxidation reaction product; The product separation unit (C) is used for performing gas-liquid separation on the oxidation reaction product to obtain waste water and waste gas.

13. The system of claim 12, wherein, The mixed feed unit (A) comprises a set of oil refining catalytic gas caustic residue storage tank (1), ethylene waste lye storage tank (2), air compressor (3), premixing device (4) and cyclone mixer (5).

14. The system of claim 13, wherein, The oil refining catalytic gas caustic residue storage tank (1) and the ethylene waste lye storage tank (2) are respectively communicated with the premixing device (4).

15. The system of claim 13, wherein, The cyclone mixer (5) is communicated with the premixing device (4) and the air compressor (3).

16. The system of claim 13 or 14, wherein, The oxidation reaction unit (B) comprises a reactor (6) communicated with the cyclone mixer (5).

17. The system of claim 16, wherein, The reactor (6) is communicated with a high-pressure steam pipeline (61).

18. The system of claim 16 or 17, wherein, The product separation unit (C) comprises a gas-water separator (7) communicated with the reactor (6).

19. The system of claim 18, wherein, The gas-water separator (7) is a cyclone separator.

20. The system of claim 18 or 19, wherein, The oxidation reaction unit (B) further comprises a heat exchanger (9) communicated with the cyclone mixer (5), the reactor (6) and the gas-water separator (7).

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