Method and system for treating oil refining catalytic gas alkaline residues

Abstract

The invention relates to the field of chemical production processes, and discloses an oil refining catalytic gas alkaline residue treatment method and system, and the method comprises the following steps: (1) pre-mixing oil refining catalytic gas alkaline residues with an ethylene waste alkali liquid to obtain a first mixture; (2) performing rotational flow mixing on the first mixture and air to obtain a second mixture; and (3) carrying out a wet oxidation reaction on the second mixture, and carrying out gas-liquid separation on the obtained oxidation reaction product to obtain wastewater and waste gas. The content of sulfide in a product after oxidation reaction treatment can be reduced to be lower than 9 * 10 <-5 > wt%, so that stable operation of a biochemical system of a subsequent sewage field is facilitated; the heat generated by the oxidation reaction of the sulfide is fully utilized, and the energy consumption of the reaction device is saved.

Description

Technical Field

[0001] The invention relates to the field of chemical production technology, and in particular to a method and system for treating oil refining catalytic gas alkali residue. Background Art

[0002] Crude oil secondary processing is a production and processing technology that uses heavy distillate oil (straight-run wax oil, coking wax oil, atmospheric heavy oil, vacuum residue oil, deasphalted oil, etc.) as raw materials, uses fluidization technology, and contacts the raw oil with a high-temperature catalyst at a certain temperature and pressure to produce a series of chemical reactions, thereby converting the raw material into a light oil product. The main products are gasoline, light diesel 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., and the liquefied gas is washed with sodium hydroxide solution. During the washing process, sodium hydroxide reacts chemically with sulfur-containing components, carbon dioxide, etc., and the generated sulfides and carbonates are dissolved in the waste alkali solution, thereby removing the acidic gas from the liquefied gas and obtaining the by-product catalytic gas alkali residue.

[0003] At present, there are two main treatment methods for catalytic gas alkali slag in China; one is moderate wet oxidation (WAO), with a reaction temperature of about 180°C and a pressure of about 3MPa. The sulfide after the reaction is about 100mg / L. This method has problems such as incomplete reaction and high sulfide, which will cause difficulties for the stable operation of the subsequent sewage treatment plant biochemical system; the other is the special biological treatment method, which uses special bacteria to carry out biological pretreatment of waste alkali liquid, with a high treatment efficiency, but the waste alkali liquid needs to be diluted in large quantities before it can enter the biochemical system, and hydrogen sulfide gas will be produced during the dilution and pH adjustment process, causing air pollution.

[0004] The alkali residue from catalytic gas refining contains relatively high concentrations of sodium sulfide and thiol organic matter. The current "mild wet oxidation (WAO)" and "special biological treatment methods" have obvious disadvantages. The sulfide concentration in the process discharge is high, which makes it difficult to stabilize the operation of the subsequent sewage treatment plant biochemical system.

[0005] Therefore, it is of great significance to treat the alkali residue of oil refining catalytic gas effectively and at low cost. Summary of the invention

[0006] Aiming at the problem that the sulfide concentration of the discharged material is high due to incomplete sulfide conversion in the existing oil refining catalytic gas alkali slag treatment process, the present invention provides a method and a system for treating the oil refining catalytic gas alkali slag.

[0007] In order to achieve the above object, the present invention provides a first aspect of a method for treating oil refining catalytic gas alkali slag, the method comprising:

[0008] (1) premixing the oil refining catalytic gas alkali residue and the ethylene waste alkali liquid to obtain a first mixed material;

[0009] (2) swirl-mixing the first mixture with air to obtain a second mixture;

[0010] (3) subjecting the second mixed material to a wet oxidation reaction, and subjecting the obtained oxidation reaction product to gas-liquid separation to obtain wastewater and waste gas.

[0011] The second aspect of the present invention provides a system for treating alkali residue from catalytic gas in oil refining, the system comprising a mixing feed unit A, an oxidation reaction unit B, and a product separation unit C which are connected in sequence; wherein:

[0012] The mixing and feeding unit A is used to premix the oil refining catalytic gas alkali residue with the ethylene waste alkali liquid, and swirl-mix the obtained first mixed material with air to obtain a second mixed material;

[0013] The oxidation reaction unit B is used to perform a wet oxidation reaction on the second mixed material to obtain an oxidation reaction product;

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

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

[0016] (1) By mixing the alkali residue of oil refining catalytic gas with the ethylene waste alkali liquid in a specific ratio for wet oxidation, the sulfide contained in the two can be more thoroughly converted. The sulfide content in the product after oxidation reaction can be reduced to less than 9×10 -5 Weight%, preferably not more than 4.6×10 -5 % by weight, which is conducive to the smooth operation of the subsequent sewage field biochemical system;

[0017] (2) Using cyclone mixing to achieve full mixing of the raw materials before the wet oxidation reaction, achieving a more complete oxidation reaction effect;

[0018] (3) The heat released by the oxidation reaction is recycled to reduce the heating steam consumption required to maintain the reaction in the system, thus saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0020] Figure 1 The present invention is a schematic diagram of a system for treating alkali slag from catalytic gas in oil refining according to an embodiment of the present invention.

[0021] Description of Reference Numerals

[0022] 1. Refinery catalytic gas alkali residue storage tank 2. Ethylene waste alkali liquid storage tank

[0023] 3. Air compressor 4. Premixer

[0024] 5. Cyclone mixer 6. Reactor

[0025] 61. High-pressure steam pipeline 62. Reactor feed port

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

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

[0028] 8. Refinery catalytic gas alkali residue feed flow pump 9. Heat exchanger

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

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

[0031] 10. Cooler DETAILED DESCRIPTION

[0032] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0033] The first aspect of the present invention provides a method for treating oil refining catalytic gas alkali slag, the method comprising:

[0034] (1) premixing the oil refining catalytic gas alkali residue and the ethylene waste alkali liquid to obtain a first mixed material;

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

[0036] (3) subjecting the second mixed material to a wet oxidation reaction, and subjecting the obtained oxidation reaction product to gas-liquid separation to obtain wastewater and waste gas.

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

[0038] According to the present invention, the oil refining catalytic gas alkali slag has a sodium sulfide content of 0.2-5% by weight, a sodium carbonate content of 1-5% by weight, a sodium hydroxide content of 2-10% by weight, an organic sulfur content of 50-2000 mg / L, and an oil content of 50-1000 mg / L.

[0039] According to the present invention, preferably, the oil refining catalytic gas alkali slag has a sodium sulfide content of 1-2% by weight, a sodium carbonate content of 1-2% by weight, a sodium hydroxide content of 2-3% by weight, an organic sulfur content of 50-1000 mg / L, and an oil content of 50-200 mg / L.

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

[0041] According to the present invention, in step (1), the premixing of the oil refining catalytic gas alkali residue and the ethylene waste alkali liquid can be carried out in any mixing manner, and the present invention has no particular limitation thereto, as long as the purpose of mixing the two homogeneously can be achieved to obtain a uniform first mixed material. It is particularly important to control the mixing ratio of the oil refining catalytic gas alkali residue and the ethylene waste alkali liquid. Preferably, the weight ratio of the oil refining catalytic gas alkali residue: ethylene waste alkali liquid is (0.2-1):1, and more preferably (0.3-0.7):1.

[0042] According to the present invention, in step (2), the air used to supply oxygen in the wet oxidation reaction is preferably compressed air that has been subjected to a compression treatment.

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

[0044] According to the present invention, in step (2), the cyclone mixing means that the first mixture and air are subjected to cyclone shearing action, so that the gas-liquid two-phase raw materials are fully and evenly mixed, which is conducive to a more thorough oxidation reaction. Preferably, the conditions for the cyclone mixing include: the pressure drop of the second mixture compared to the first mixture is less than 0.01 MPa.

[0045] According to the present invention, in step (2), after the cyclonic mixing, air exists in the form of microbubbles in the second mixed material obtained.

[0046] In the present invention, the swirl mixing makes the average particle size of the air microbubbles in the second mixed material be 1-8 mm, which is conducive to more sufficient distribution of the air in the liquid raw material and achieve uniform mixing, thereby promoting a more thorough oxidation reaction. Preferably, the solubility of air in the second mixed material is ≥7.5% by volume.

[0047] In the present invention, the average particle size of the air microbubbles in the second mixed material is obtained by testing an online sample using a microscope.

[0048] According to the present invention, in step (3), the wet oxidation reaction can be carried out in a conventional reactor in the wet oxidation process, and the present invention has no particular limitation on this. For the alkaline mixed material in the method of the present invention, the conditions of the wet oxidation reaction include: a temperature of 150-350°C, preferably 190-220°C; a pressure of 2.1-20MPa, preferably 3-3.2MPa. Based on the above reaction conditions, using air as an oxidant, the sulfide (referring to a compound containing S with a valence of -2) and organic matter contained in the second mixed material undergo an oxidation reaction, wherein the sulfide is converted into sulfate or sulfite, and the organic matter is partially oxidized and decomposed into carbon dioxide and water or converted into low molecular weight organic matter, while releasing reaction heat to obtain a high-temperature oxidation reaction product. The oxidation reaction product is a mixture of gas and liquid phases.

[0049] According to the present invention, after the wet oxidation reaction, the sulfide content in the oxidation reaction product obtained is less than 9×10 -5 % by weight, meeting the index requirements for sewage discharge, which is beneficial to the smooth operation of the sewage field biochemical system.

[0050] In the present invention, the sulfide in the oxidation reaction product refers to a compound containing S with a valence of -2, such as unconverted Na 2 S.

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

[0052] According to the present invention, in step (3), the gas-liquid separation can be carried out by any method capable of achieving gas-liquid two-phase separation, and the present invention has no particular limitation on this. Preferably, the gas-liquid separation adopts a cyclone separation method, which can achieve a more adequate separation effect.

[0053] According to the present invention, the cyclone separation refers to using the centrifugal force of the cyclone field to reduce the concentration of wastewater entrained by the gas in the gas-liquid mixture as much as possible. Preferably, the conditions of the cyclone separation include: split ratio <8%. After the cyclone separation, the amount of wastewater carried by the waste gas obtained is <20mg / m 3 .

[0054] In the present invention, the split ratio refers to the ratio of the volume of the dispersed phase (the phase with a smaller volume) to the volume of the material at the feed inlet before the cyclone separation during the cyclone separation process.

[0055] In the present invention, the main components of the wastewater include sulfate, sulfite, sodium hydroxide, etc., among which the content of sulfide (referring to compounds containing S with a valence of -2) has reached the index requirements for discharge into sewage fields; the main components of the waste gas include volatile organic compounds.

[0056] According to the present invention, preferably, the method may further include: before the gas-liquid separation, heat exchanging the oxidation reaction product with the second mixed material. Preheating the second mixed material by heat exchange can reduce energy consumption for the subsequent wet oxidation reaction, and the oxidation reaction product is cooled by heat exchange, which is more conducive to gas-liquid separation.

[0057] In view of the high concentration of sulfide in the catalytic gas alkali residue of oil refining and the great difficulty in treatment, the present invention adopts a method of mixing the catalytic gas alkali residue of oil refining with ethylene waste alkali liquid in a specific ratio for wet oxidation, so that the sulfide content in the product obtained after treatment can be reduced to less than 9×10 -5 Weight%, preferably not more than 4.6×10 -5 % by weight, which is conducive to the smooth operation of the subsequent sewage treatment plant biochemical system. In the treatment method of the present invention, a cyclone mixing method is used to achieve full mixing of the raw materials before the wet oxidation reaction, which promotes the full conversion of sulfides during the oxidation process. In the treatment method of the present invention, the heat generated by the oxidation reaction can be recycled, reducing the energy consumption required to maintain the oxidation reaction, thereby saving costs.

[0058] The second aspect of the present invention provides a system for treating alkali residue from oil refining catalytic gas, such as Figure 1 As shown, the system comprises a mixed feed unit A, an oxidation reaction unit B, and a product separation unit C which are connected in sequence; wherein,

[0059] The mixing and feeding unit A is used to premix the oil refining catalytic gas alkali residue with the ethylene waste alkali liquid, and swirl-mix the obtained first mixed material with air to obtain a second mixed material;

[0060] The oxidation reaction unit B is used to perform a wet oxidation reaction on the second mixed material to obtain an oxidation reaction product;

[0061] The product separation unit C is used to separate the oxidation reaction product into gas and liquid to obtain waste water and waste gas.

[0062] According to the present invention, the mixed feeding unit A comprises a refinery catalytic gas alkali residue storage tank 1, an ethylene waste alkali liquid storage tank 2, an air compressor 3, a premixer 4 and a cyclone mixer 5.

[0063] According to the present invention, the oil refining catalytic gas alkali residue storage tank 1 and the ethylene waste alkali liquid storage tank 2 are respectively connected to the premixer 4.

[0064] According to the present invention, the cyclone mixer 5 is connected to the premixer 4 and the air compressor 3 .

[0065] According to the present invention, the refinery catalytic gas alkali residue storage tank 1 is used to store the refinery catalytic gas alkali residue produced as a by-product of the crude oil processing system outside the boundary area; the ethylene waste alkali liquid storage tank 2 is used to store the ethylene waste alkali liquid produced by the alkali washing tower of the ethylene device outside the boundary area; the air compressor 3 is used to pressurize the air and provide the power of the oxidant gas source required for the oxidation reaction; the premixer 4 is used to premix the refinery catalytic gas alkali residue with the ethylene waste alkali liquid to obtain a first mixture; the cyclone mixer 5 is used to cyclone mix the first mixture with air to obtain a second mixture.

[0066] In the present invention, the premixer 4 may be a conventional device for mixing liquid materials, and the present invention has no particular limitation on this.

[0067] In the present invention, the structure of the cyclone mixer 5 includes a tangential feed port, a mixing column section, a mixing taper and a gradually expanding drain port, and the gas-liquid two-phase is fully mixed by the cyclone shear force, so that the solubility of air in the obtained second mixture is ≥7.5% by volume, and the air exists in the form of microbubbles (the average particle size of the air microbubbles is 1-8 mm), so that the gas-liquid two-phase raw materials are fully and uniformly mixed. The cyclone mixer 5 can be obtained through conventional commercial channels.

[0068] According to the present invention, preferably, the mixed feed unit A may also include a refinery catalytic gas alkali slag feed flow pump 8 and a high-pressure feed pump ( Figure 1 The feed flow pump 8 of the catalytic gas alkali residue of the refinery is connected to the catalytic gas alkali residue storage tank 1 and the premixer 4, and is used to control the feed amount and adjust the mixing ratio of the catalytic gas alkali residue of the refinery and the ethylene waste alkali liquid. The high-pressure feed pump is connected to the premixer 4 and the cyclone mixer 5, and is used to increase the pressure of the first mixture and convey it to the cyclone mixer 5 for cyclone mixing with air.

[0069] According to the present invention, the oxidation reaction unit B comprises a reactor 6 connected to the cyclone mixer 5. The reactor 6 is connected to 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 invention, the reactor 6 can be a conventional reactor in the wet oxidation process. The second mixed material from the mixed feed unit A enters the reactor 6 from the reactor feed port 62. Under medium temperature and medium high pressure conditions, the sulfide (referring to a compound containing S with a valence of -2) and the organic matter contained in the second mixed material undergo an oxidation reaction using air as an oxidant, wherein the sulfide is converted into sulfate or sulfite, and the organic matter is partially oxidized and decomposed into carbon dioxide and water or converted into low molecular weight organic matter, while releasing reaction heat to obtain a high temperature oxidation reaction product (wherein the sulfide content is less than 9×10 -5 wt %), and is drawn out from the reactor outlet 63. The oxidation reaction product is a mixture of gas and liquid phases.

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

[0072] According to the present invention, preferably, the gas-water separator 7 is a cyclone separator, and its structure includes a tangential feed port, a column-cone mixing and separation section, an exhaust port and a liquid discharge port. Through the centrifugal force in the cyclone field, a more sufficient gas-liquid separation effect can be obtained, and the waste water carrying amount in the separated waste gas is less than 20 mg / m 3 .

[0073] According to the present invention, preferably, the product separation unit C may further include a cooler 10. The cooler 10 is connected to the reactor 6 and the gas-water separator 7, and is used to cool the oxidation reaction product before the gas-liquid separation, so as to obtain a better separation effect.

[0074] According to the present invention, preferably, the oxidation reaction unit B also includes a heat exchanger 9, which connects the cyclone mixer 5, the reactor 6 and the gas-water separator 7, and is used for heat exchanging the oxidation reaction product with the second mixed material before the gas-liquid separation.

[0075] In the present invention, 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 connected to the cyclone mixer 5; the reaction raw material heat exchange discharge port 92 is connected to the reactor feed port 62 of the reactor 6; the reaction product heat exchange feed port 93 is connected to the reactor discharge port 63 of the reactor 6; the reaction product heat exchange discharge port 94 is connected to the gas-water separator 7, preferably connected to the gas-water separator 7 via the cooler 10. The second mixed material from the mixed feed unit A enters the heat exchanger 9 from the reaction raw material heat exchange feed port 91, performs heat exchange with the high-temperature oxidation reaction product from the reactor discharge port 63 and enters the heat exchanger 9 from the reaction product heat exchange feed port 93, and leaves the heat exchanger 9 from the reaction raw material heat exchange discharge port 92, and then enters the reactor 6 from 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 setting the heat exchanger 9, the oxidation reaction unit B can save operating energy consumption, greatly reduce the consumption of high-pressure hot steam, and facilitate the gas-liquid separation of the oxidation reaction product in the product separation unit C.

[0076] The following combination Figure 1 The invention describes a method for treating oil refining catalytic gas alkali slag by using the treatment system for oil refining catalytic gas alkali slag provided by the invention.

[0077] (1) In the mixed feed unit A, the refinery catalytic gas alkali residue in the refinery catalytic gas alkali residue storage tank 1 is pressurized by the refinery catalytic gas alkali residue feed flow pump 8, and enters the premixer 4 for premixing with the ethylene waste alkali liquid from the ethylene waste alkali liquid storage tank 2 (the weight ratio of the refinery catalytic gas alkali residue to the ethylene waste alkali liquid is 0.2-1:1), thereby obtaining a first mixed material;

[0078] (2) The first mixture is pressurized by a high-pressure feed pump and enters the cyclone mixer 5 for cyclone mixing with the air from the air compressor 3 (the volume ratio of the first mixture to the air is 0.05-0.2:1; the condition of cyclone mixing is that the pressure drop of the second mixture compared with the first mixture is less than 0.01 MPa), thereby obtaining a second mixture (in the second mixture, the average particle size of the air microbubbles is 1-8 mm, and the solubility of air is ≥7.5 volume %);

[0079] (3-1) In the oxidation reaction unit B, the second mixed material enters from the reaction raw material heat exchange feed port 91 of the heat exchanger 9, and performs heat exchange with the high-temperature oxidation reaction product (190-220° C.) from the reactor discharge port 63 and entering from the reaction product heat exchange feed port 93 of the heat exchanger 9 in the heat exchanger 9. After the heat exchange, the second mixed material is preheated to 140-170° C. and leaves from the reaction raw material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after the heat exchange, the oxidation reaction product is cooled to 65-120° C., and is led out from the reaction product heat exchange discharge port 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 mixed material. In the reactor 6, the second mixed material is subjected to a wet oxidation reaction at 150-350°C and 2.1-20 MPa to obtain a high-temperature oxidation reaction product (sulfide content <9×10 -5 wt %) is led out from the reactor discharge port 63 and enters the heat exchanger 9 to perform the above-mentioned heat exchange and cooling process;

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

[0082] The present invention will be described in detail below by way of examples. In the following examples and comparative examples,

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

[0084] Table 1

[0085] Components content NaOH 2.5 wt% <![CDATA[Na 2 S]]> 1.2 wt% <![CDATA[Na 2 CO 3 ]]> 1 wt% Organic sulfur 100mg / L Oil content 200mg / L

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

[0087] Table 2

[0088] Components content NaOH 2 wt% <![CDATA[Na 2 S]]> 1.2 wt% <![CDATA[Na 2 CO 3 ]]> 1.5 wt% Organic sulfur 150mg / L Oil content 300mg / L

[0089] Example 1

[0090] (1) In the mixed feeding unit A, the refinery catalytic gas alkali residue in the refinery catalytic gas alkali residue storage tank 1 is pressurized to 0.6 MPa by the refinery catalytic gas alkali residue feed flow pump 8, and enters the premixer 4 for premixing with the ethylene waste alkali liquid from the ethylene waste alkali liquid storage tank 2 (the weight ratio of the refinery catalytic gas alkali residue to the ethylene waste alkali liquid is 0.3:1), thereby obtaining a first mixed material;

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

[0092] (3-1) In the oxidation reaction unit B, the second mixed material enters from the reaction raw material heat exchange feed port 91 of the heat exchanger 9, and performs heat exchange with the high-temperature oxidation reaction product (200° C.) coming from the reactor discharge port 63 and entering from the reaction product heat exchange feed port 93 of the heat exchanger 9 in the heat exchanger 9. After the heat exchange, the second mixed material is preheated to 160° C. and leaves from the reaction raw material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after the 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 the second mixed material. In the reactor 6, the second mixed material is subjected to a wet oxidation reaction under the conditions of 200° C. and 3.2 MPa. The obtained high-temperature oxidation reaction product (the sulfide content of which is shown in Table 3) is drawn out from the reactor outlet 63 and enters the heat exchanger 9 to perform the above-mentioned heat exchange and cooling process.

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

[0095] Example 2

[0096] (1) In the mixed feeding unit A, the refinery catalytic gas alkali residue in the refinery catalytic gas alkali residue storage tank 1 is pressurized to 0.6 MPa by the refinery catalytic gas alkali residue feed flow pump 8, and enters the premixer 4 for premixing with the ethylene waste alkali liquid from the ethylene waste alkali liquid storage tank 2 (the weight ratio of the refinery catalytic gas alkali residue to the ethylene waste alkali liquid is 0.6:1), thereby obtaining a first mixed material;

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

[0098] (3-1) In the oxidation reaction unit B, the second mixed material enters from the reaction raw material heat exchange feed port 91 of the heat exchanger 9, and performs heat exchange with the high-temperature oxidation reaction product (200° C.) coming from the reactor discharge port 63 and entering from the reaction product heat exchange feed port 93 of the heat exchanger 9 in the heat exchanger 9. After the heat exchange, the second mixed material is preheated to 160° C. and leaves from the reaction raw material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after the 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 the second mixed material. In the reactor 6, the second mixed material is subjected to a wet oxidation reaction under the conditions of 200° C. and 3.2 MPa. The obtained high-temperature oxidation reaction product (the sulfide content of which is shown in Table 3) is drawn out from the reactor outlet 63 and enters the heat exchanger 9 to perform the above-mentioned heat exchange and cooling process.

[0100] (3-2) In the product separation unit C, the oxidation reaction product after heat exchange and cooling is further cooled to 65° C. by the cooler 10, and then enters the gas-water separator 7 (using a cyclone separator) for gas-liquid separation (separation condition: split ratio is 5%), and the resulting waste gas is discharged from the waste gas discharge pipeline 71 (the amount of waste water carried in the waste gas is 12 mg / m 3 ), and sent to the incinerator outside the boundary area for incineration treatment; the resulting wastewater is discharged to the outside of the boundary area through the wastewater discharge pipeline 72, and subsequently enters the biochemical system of the sewage field for further treatment.

[0101] Example 3

[0102] (1) In the mixed feeding unit A, the refinery catalytic gas alkali residue in the refinery catalytic gas alkali residue storage tank 1 is pressurized to 0.6 MPa by the refinery catalytic gas alkali residue feed flow pump 8, and enters the premixer 4 for premixing with the ethylene waste alkali liquid from the ethylene waste alkali liquid storage tank 2 (the weight ratio of the refinery catalytic gas alkali residue to the ethylene waste alkali liquid is 1:1), thereby obtaining a first mixed material;

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

[0104] (3-1) In the oxidation reaction unit B, the second mixed material enters from the reaction raw material heat exchange feed port 91 of the heat exchanger 9, and performs heat exchange with the high-temperature oxidation reaction product (200° C.) coming from the reactor discharge port 63 and entering from the reaction product heat exchange feed port 93 of the heat exchanger 9 in the heat exchanger 9. After the heat exchange, the second mixed material is preheated to 160° C. and leaves from the reaction raw material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after the 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 the second mixed material. In the reactor 6, the second mixed material is subjected to a wet oxidation reaction under the conditions of 200° C. and 3.2 MPa. The obtained high-temperature oxidation reaction product (the sulfide content of which is shown in Table 3) is drawn out from the reactor outlet 63 and enters the heat exchanger 9 to perform the above-mentioned heat exchange and cooling process.

[0106] (3-2) In the product separation unit C, the oxidation reaction product after heat exchange and cooling is further cooled to 65° C. by the cooler 10, and then enters the gas-water separator 7 (using a cyclone separator) for gas-liquid separation (separation condition: split ratio is 5%), and the resulting waste gas is discharged from the waste gas discharge pipeline 71 (the amount of waste water carried in the waste gas is 12 mg / m 3 ), and sent to the incinerator outside the boundary area for incineration treatment; the resulting wastewater is discharged to the outside of the boundary area through the wastewater discharge pipeline 72, and subsequently enters the biochemical system of the sewage field for further treatment.

[0107] Example 4

[0108] (1) In the mixed feeding unit A, the refinery catalytic gas alkali residue in the refinery catalytic gas alkali residue storage tank 1 is pressurized to 0.6 MPa by the refinery catalytic gas alkali residue feed flow pump 8, and enters the premixer 4 for premixing with the ethylene waste alkali liquid from the ethylene waste alkali liquid storage tank 2 (the weight ratio of the refinery catalytic gas alkali residue to the ethylene waste alkali liquid is 0.6:1), thereby obtaining a first mixed material;

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

[0110] (3-1) In the oxidation reaction unit B, the second mixed material enters from the reaction raw material heat exchange feed port 91 of the heat exchanger 9, and performs heat exchange with the high-temperature oxidation reaction product (200° C.) coming from the reactor discharge port 63 and entering from the reaction product heat exchange feed port 93 of the heat exchanger 9 in the heat exchanger 9. After the heat exchange, the second mixed material is preheated to 160° C. and leaves from the reaction raw material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after the 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 the second mixed material. In the reactor 6, the second mixed material is subjected to a wet oxidation reaction under the conditions of 200° C. and 3.2 MPa. The obtained high-temperature oxidation reaction product (the sulfide content of which is shown in Table 3) is drawn out from the reactor outlet 63 and enters the heat exchanger 9 to perform the above-mentioned heat exchange and cooling process.

[0112] (3-2) In the product separation unit C, the oxidation reaction product after heat exchange and cooling is further cooled to 65° C. by the cooler 10, and then enters the gas-water separator 7 (using a cyclone separator) for gas-liquid separation (separation condition: split ratio is 5%), and the resulting waste gas is discharged from the waste gas discharge pipeline 71 (the amount of waste water carried in the waste gas is 12 mg / m 3 ), and sent to the incinerator outside the boundary area for incineration treatment; the resulting wastewater is discharged to the outside of the boundary area through the wastewater discharge pipeline 72, and subsequently enters the biochemical system of the sewage field for further treatment.

[0113] Example 5

[0114] 1) In the mixed feeding unit A, the refinery catalytic gas alkali residue in the refinery catalytic gas alkali residue storage tank 1 is pressurized to 0.6 MPa by the refinery catalytic gas alkali residue feed flow pump 8, and enters the premixer 4 for premixing with the ethylene waste alkali liquid from the ethylene waste alkali liquid storage tank 2 (the weight ratio of the refinery catalytic gas alkali residue: the ethylene waste alkali liquid is 1.5:1), to obtain a first mixed material;

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

[0116] (3-1) In the oxidation reaction unit B, the second mixed material enters from the reaction raw material heat exchange feed port 91 of the heat exchanger 9, and performs heat exchange with the high-temperature oxidation reaction product (200° C.) coming from the reactor discharge port 63 and entering from the reaction product heat exchange feed port 93 of the heat exchanger 9 in the heat exchanger 9. After the heat exchange, the second mixed material is preheated to 160° C. and leaves from the reaction raw material heat exchange discharge port 92 of the heat exchanger 9 and enters the reactor 6; after the 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 the second mixed material. In the reactor 6, the second mixed material is subjected to a wet oxidation reaction under the conditions of 200° C. and 3.2 MPa. The obtained high-temperature oxidation reaction product (the sulfide content of which is shown in Table 3) is drawn out from the reactor outlet 63 and enters the heat exchanger 9 to perform the above-mentioned heat exchange and cooling process.

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

[0119] Comparative Example 1

[0120] The method of Example 1 is different in that the alkali residue of the catalytic gas from oil refinery is not premixed with the ethylene waste alkali liquid, but the alkali residue of the catalytic gas from oil refinery is used directly as a raw material instead of the "first mixed material" to sequentially carry out step (2), step (3-1) and step (3-2). The other conditions are the same as those of Example 1.

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

[0122] Comparative Example 2

[0123] The method of Example 1 is followed, except that the cyclone mixer 5 is replaced by a static mixer to obtain a second mixed material (in the second mixed material, the average particle size of the air bubbles is 16 mm, and the solubility of air is 5 volume %). Other conditions are the same as those of 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 products Sulfide content / weight% Oxidation reaction product (Example 1) <![CDATA[2.8×10 -5 ]]> Oxidation reaction product (Example 2) <![CDATA[1.8×10 -5 ]]> Oxidation Reaction Product (Example 3) <![CDATA[4.6×10 -5 ]]> Oxidation Reaction Product (Example 4) <![CDATA[6.4×10 -5 ]]> Oxidation Reaction Product (Example 5) <![CDATA[7.4×10 -5 ]]> Oxidation reaction product (Comparative Example 1) <![CDATA[27.6×10 -5 ]]> Oxidation reaction product (Comparative Example 2) <![CDATA[23×10 -5 ]]>

[0127] As shown in Table 3, the sulfide content in the catalytic gas alkali residue of the oil refining can be fully converted by mixing the catalytic gas alkali residue of the oil refining with ethylene waste alkali liquid for wet oxidation, and the sulfide content in the treated product can be reduced to less than 9×10 -5 wt%. In Examples 1-3, by adjusting the weight ratio of the refining catalytic gas alkali residue to the ethylene waste alkali liquid to be in the range of (0.2-1):1 and adopting suitable cyclone mixing conditions, the sulfide content in the treated product can be reduced to no more than 4.6×10 -5 wt%. In particular, in Comparative Examples 1-2, which do not use the method of the present invention, the sulfide content in the process output is significantly high.

[0128] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for treating oil refining catalytic gas alkali slag, characterized in that: The method includes: (1) premixing the oil refining catalytic gas alkali residue and the ethylene waste alkali liquid to obtain a first mixed material; (2) swirl-mixing the first mixture with air to obtain a second mixture; (3) subjecting the second mixed material to a wet oxidation reaction, and subjecting the obtained oxidation reaction product to gas-liquid separation to obtain wastewater and waste gas.

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

3. The method according to claim 1 or 2, wherein: The ethylene waste alkali solution contains 0.2-2% by weight of sodium sulfide, 0.5-2% by weight of sodium carbonate and 1-3% by weight of sodium hydroxide; Preferably, the organic sulfur content in the ethylene waste alkali solution is 50-500 mg / L; Preferably, the oil content in the ethylene waste alkali liquid is 50-1000 mg / L.

4. The method according to any one of claims 1 to 3, wherein: In step (1), the weight ratio of the oil refining catalytic gas alkali residue to the ethylene waste alkali liquid is (0.2-1):1, preferably (0.3-0.7):

1.

5. The method according to any one of claims 1 to 4, wherein: In step (2), the volume ratio of the first mixture to air is (0.05-0.2):1, preferably (0.08-0.12):1; Preferably, the conditions for the cyclonic mixing include: the pressure drop of the second mixed material compared to the first mixed material is less than 0.01 MPa; Preferably, in the second mixture, air exists in the form of microbubbles; Preferably, in the second mixture, the average particle size of the air microbubbles is 1-8 mm; Preferably, the solubility of air in the second mixed material is ≥7.5% by volume.

6. The method according to any one of claims 1 to 5, wherein: In step (3), the conditions of the wet oxidation reaction include: temperature of 150-350° C., preferably 190-220° C.; pressure of 2.1-20 MPa, preferably 3-3.2 MPa; Preferably, the sulfide content in the oxidation reaction product is less than 9×10 -5 weight%.

7. The method according to any one of claims 1 to 6, wherein: In step (3), the gas-liquid separation is carried out by cyclone separation; Preferably, the conditions for cyclone separation include: split ratio < 8%; Preferably, the amount of wastewater carried in the waste gas is less than 20 mg / m 3 .

8. The method according to any one of claims 1 to 7, wherein: The method further comprises: before the gas-liquid separation, heat exchanging the oxidation reaction product with a second mixed material.

9. A system for treating oil refining catalytic gas alkali residue, characterized in that: The system comprises a mixed feed unit (A), an oxidation reaction unit (B), and a product separation unit (C) which are connected in sequence; wherein: The mixing and feeding unit (A) is used to premix the oil refining catalytic gas alkali residue with the ethylene waste alkali liquid, and swirl-mix the obtained first mixed material with air to obtain a second mixed material; The oxidation reaction unit (B) is used to perform a wet oxidation reaction on the second mixed material to obtain an oxidation reaction product; The product separation unit (C) is used to separate the oxidation reaction product into gas and liquid to obtain waste water and waste gas.

10. The system according to claim 9, wherein: The mixed feeding unit (A) comprises a refining catalytic gas alkali residue storage tank (1), an ethylene waste alkali liquid storage tank (2), an air compressor (3), a premixer (4) and a cyclone mixer (5).

11. The system according to claim 10, wherein: The oil refining catalytic gas alkali residue storage tank (1) and the ethylene waste alkali liquid storage tank (2) are respectively connected to the premixer (4); Preferably, the cyclone mixer (5) is connected to the premixer (4) and the air compressor (3).

12. The system according to claim 10 or 11, wherein: The oxidation reaction unit (B) comprises a reactor (6) connected to the cyclone mixer (5); Preferably, the reactor (6) is in communication with a high-pressure steam pipeline (61).

13. The system according to claim 12, wherein: The product separation unit (C) comprises a gas-water separator (7) connected to the reactor (6); Preferably, the gas-water separator (7) is a cyclone separator.

14. The system according to claim 13, wherein: The oxidation reaction unit (B) further comprises a heat exchanger (9), wherein the heat exchanger (9) is connected to the cyclone mixer (5), the reactor (6) and the gas-water separator (7).

Images