Comprehensive utilization method of materials in zeolite molecular sieve production process

Abstract

The invention belongs to the technical field of resource recovery, and particularly relates to a comprehensive utilization method of materials in a zeolite molecular sieve production process. The invention provides a comprehensive utilization method of materials in a zeolite molecular sieve production process, which comprises the following steps: mixing an aluminum-containing filter cake with water, and sequentially carrying out pulping and first solid-liquid separation to obtain a sodium metaaluminate solution; the mass percentage content of sodium metaaluminate in the aluminum-containing filter cake is 1%-2%; mixing the sodium metaaluminate solution with silicon-containing wastewater, and carrying out precipitation reaction to obtain low-silicon wastewater; the concentration of silicon dioxide in the silicon-containing wastewater is 60-2000mg / L; the concentration of silicon dioxide in the low-silicon wastewater is below 40mg / L. According to the resource utilization method provided by the invention, starting from the concept of treating waste with waste, effective components are further extracted from the aluminum-containing filter cake generated in the molecular sieve production process and are used for removing silicon, so that the overall aluminum-containing filter cake amount can be reduced, and the water treatment cost can be reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of resource recovery, and in particular relates to a method for comprehensive utilization of materials in a zeolite molecular sieve production process. Background Art

[0002] In the preparation process of molecular sieve raw powder, the amount of flushing water is large, and the wastewater obtained by washing contains silica, which needs to be treated by a membrane system. In order to prevent membrane pollution and clogging, improve treatment efficiency and stability, and meet water quality requirements, silica must be removed from the wastewater before entering the membrane system for treatment. The conventional method for removing silica is to add a desiliconizer, such as sodium aluminate or magnesium chloride. These agents are expensive as desiliconizers, accounting for 30-50% of the water treatment cost, and will also produce a large amount of inorganic silicon-aluminum sludge.

[0003] On the other hand, after the molecular sieve mother liquor reacts with aluminum hydrogen powder, the aluminum-containing filter cake produced by the filter press is generally directly collected and transported for disposal, and the processing volume is large. Therefore, the treatment cost of aluminum-containing filter cake and wastewater in the molecular sieve production process is relatively high. Summary of the invention

[0004] The purpose of the present invention is to provide a method for comprehensive utilization of materials in the production process of zeolite molecular sieves. The method provided by the present invention recycles the aluminum-containing filter cake obtained in the molecular sieve production process as a silicon remover for silicon-containing wastewater, thereby achieving waste treatment with waste and reducing the cost of treating the aluminum-containing filter cake and wastewater.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a method for comprehensive utilization of materials in the production process of zeolite molecular sieve, comprising the following steps:

[0007] The aluminum-containing filter cake is mixed with water, and pulping and first solid-liquid separation are performed in sequence to obtain a sodium aluminate solution; the mass percentage of sodium aluminate in the aluminum-containing filter cake is 1% to 2%;

[0008] The sodium aluminate solution and silicon-containing wastewater are mixed to carry out precipitation reaction to obtain low-silicon wastewater; the concentration of silicon dioxide in the silicon-containing wastewater is 60-2000 mg / L; the concentration of silicon dioxide in the low-silicon wastewater is below 40 mg / L.

[0009] Preferably, the preparation process of the aluminum-containing filter cake comprises the following steps:

[0010] The molecular sieve mother liquor and aluminum hydrogen powder are mixed, and double decomposition reaction and second solid-liquid separation are carried out in sequence to obtain the aluminum-containing filter cake; the concentration of sodium oxide in the molecular sieve mother liquor is above 110 g / L.

[0011] Preferably, the molecular sieve mother liquor comprises an LTA type molecular sieve mother liquor, a MOR type molecular sieve mother liquor or a FAU type molecular sieve mother liquor;

[0012] The mass percentage of aluminum oxide in the aluminum hydrogen powder is more than 60%; the mass ratio of sodium oxide in the molecular sieve mother liquor to aluminum oxide in the aluminum hydrogen powder is 10-20:1.

[0013] Preferably, the temperature of the metathesis reaction is above 100°C and the time is 3 to 5 hours;

[0014] The second solid-liquid separation is suction filtration or pressure filtration; the feeding pressure of the pressure filtration is 0.1-0.2 MPa, the air pressure is 0.6-0.8 MPa, and the air blowing time is 25-35 min.

[0015] Preferably, the mass ratio of the aluminum-containing filter cake to water is 1:2.5-3.5; and the particle size of the aluminum-containing filter cake in the slurry obtained by beating is less than 0.175 mm.

[0016] Preferably, the beating speed is 50-70 rpm and the time is 1-2 hours.

[0017] Preferably, the first solid-liquid separation comprises filtration and filter pressing performed sequentially.

[0018] Preferably, the filtration includes filter paper filtration or three-stage filtration; the three-stage filtration includes first filtration, second filtration and third filtration performed in sequence; the mesh aperture of the first filtration is 4 to 6 mm; the mesh aperture of the second filtration is 2 to 4 mm; the mesh aperture of the third filtration is 0.8 to 2 mm.

[0019] Preferably, the feed pressure of the filter press is 1-2 MPa, the pressing pressure is 6-10 MPa, and the air flow rate of the filter cloth is 5 L / m 2 ·s or less.

[0020] Preferably, the sodium aluminate solution is Al 2 O 3 The silicon-containing wastewater is SiO 2 The mass ratio is 0.75 to 1:1.

[0021] The present invention provides a method for comprehensive utilization of materials in the production process of zeolite molecular sieves, comprising the following steps: mixing an aluminum-containing filter cake with water, and sequentially performing pulping and a first solid-liquid separation to obtain a sodium aluminate solution; the mass percentage of sodium aluminate in the aluminum-containing filter cake is 1% to 2%; mixing the sodium aluminate solution with silicon-containing wastewater, performing a precipitation reaction, and obtaining low-silicon wastewater; the concentration of silicon dioxide in the silicon-containing wastewater is 60 to 2000 mg / L; the concentration of silicon dioxide in the low-silicon wastewater is below 40 mg / L. The comprehensive utilization method provided by the present invention is based on the concept of "treating waste with waste", and further extracts effective components from the aluminum-containing filter cake produced in the production process of the molecular sieve for silicon removal, which can reduce the overall amount of aluminum-containing filter cake and reduce the cost of water treatment. Specifically, the present invention uses the aluminum-containing filter cake after pressure filtration to pulp again, so that the effective component sodium aluminate in the aluminum-containing filter cake is dissolved, and then filtered to obtain a low-concentration sodium aluminate solution, which can be directly used for wastewater silicon removal, replacing the use of normal silicon removal agents. At the same time, since the concentration of the obtained sodium aluminate solution is low, the dosage can be accurately controlled when used as a silicon removal agent, thereby reducing the formation of precipitation and reducing the generation of solid waste in the water treatment process. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 The present invention is a flow chart of the existing treatment process of the aluminum-containing filter cake obtained in the molecular sieve production process;

[0024] Figure 2 A process flow chart for resource utilization of aluminum-containing filter cake obtained in the molecular sieve production process provided by the present invention;

[0025] Figure 3 This is a real picture of the silicon removal effect of using the sodium aluminate solution obtained from the aluminum-containing filter cake and the ordinary sodium aluminate solution as wastewater silicon removal agents in Example 1. DETAILED DESCRIPTION

[0026] The present invention provides a method for comprehensive utilization of materials in the production process of zeolite molecular sieve, comprising the following steps:

[0027] The aluminum-containing filter cake is mixed with water, and pulping and first solid-liquid separation are performed in sequence to obtain a sodium aluminate solution; the mass percentage of sodium aluminate in the aluminum-containing filter cake is 1% to 2%;

[0028] The sodium aluminate solution and silicon-containing wastewater are mixed to carry out precipitation reaction to obtain low-silicon wastewater; the concentration of silicon dioxide in the silicon-containing wastewater is 60-2000 mg / L; the concentration of silicon dioxide in the low-silicon wastewater is below 40 mg / L.

[0029] In the present invention, unless otherwise specified, all raw material components are commercially available products well known to those skilled in the art.

[0030] The invention mixes the aluminum-containing filter cake with water, and sequentially performs pulping and first solid-liquid separation to obtain a sodium metaaluminate solution.

[0031] In the present invention, the preparation process of the aluminum-containing filter cake may include the following steps:

[0032] The molecular sieve mother liquor and aluminum hydrogen powder are mixed, and double decomposition reaction and second solid-liquid separation are carried out in sequence to obtain the aluminum-containing filter cake; the concentration of sodium oxide in the molecular sieve mother liquor is above 110 g / L.

[0033] In the present invention, the molecular sieve mother liquor may include an LTA molecular sieve mother liquor, a MOR molecular sieve mother liquor or a FAU molecular sieve mother liquor; the concentration of sodium oxide in the molecular sieve mother liquor may be above 110 g / L, and in a specific embodiment, may be 150 g / L; the concentration of aluminate may be 5 to 20 g / L, and in a specific embodiment, may be 8 g / L; the mass percentage of aluminum oxide in the aluminum hydrogen powder may be above 60%, and in a specific embodiment, may be 60%, 64% or 68%; the molecular sieve mother liquor The mass ratio of sodium oxide to aluminum oxide in aluminum hydroxide powder can be 10 to 20:1, and in a specific embodiment, can be 12:1, 15:1 or 18:1; the raw material for the double decomposition reaction also includes sodium hydroxide solution; the concentration of the sodium hydroxide solution can be 200 to 500 g / L, and in a specific embodiment, can be 250 g / L, 330 g / L or 400 g / L; the volume ratio of the molecular sieve mother liquor to liquid caustic soda can be 5 to 20:1, and in a specific embodiment, can be 10:1, 12:1 or 15:1.

[0034] In the present invention, the temperature of the double decomposition reaction can be above 100°C, and in a specific embodiment, it can be 100°C, 120°C or 150°C; the time can be 3 to 5 hours, and in a specific embodiment, it can be 4 hours or 5 hours; the double decomposition reaction is carried out under stirring conditions; the stirring speed is 50 to 70 rpm, and in a specific embodiment, it can be 60 rpm.

[0035] In the present invention, the second solid-liquid separation can be suction filtration or pressure filtration; the feeding pressure of the pressure filtration can be 0.1-0.2MPa, the air pressure can be 0.6-0.8MPa, and the air blowing time can be 25-35min. In the present invention, the hydrogen aluminum powder is mainly aluminum oxide, and the rest are potassium, calcium, sodium, magnesium, zinc, silicon, sulfur, phosphorus, etc.; the main component of the molecular sieve mother liquor is sodium oxide, and there are dissolved metasilicates. Through the second solid-liquid separation, the liquid phase obtained is a relatively high concentration sodium metaaluminate solution, the main components of which are sodium oxide and aluminum oxide; the solid phase is a sodium aluminate aluminum filter cake, including impurities of the hydrogen aluminum powder, containing solid aluminum oxide, iron oxide, silicon dioxide, sodium oxide, calcium sulfate, etc. All sodium oxide and aluminum oxide cannot be extracted from the filtrate after the second solid-liquid separation, and the aluminum-containing filter cake still contains a lot of soluble sodium oxide and aluminum oxide.

[0036] In the present invention, the aluminum-containing filter cake is an aluminum-containing filter cake obtained in the molecular sieve production process; the mass percentage of sodium aluminate in the aluminum-containing filter cake can be 1% to 2%, and in a specific embodiment, it can be 1.5%; the mass ratio of the aluminum-containing filter cake to water can be 1:2.5 to 3.5, and in a specific embodiment, it can be 1:3; the particle size of the aluminum-containing filter cake in the slurry obtained by beating can be less than 0.175 mm; the rotation speed of the beating can be 50 to 70 rpm, and the time can be 1 to 2 hours; the purpose of the beating is to obtain a uniformly dispersed slurry and make the particle size of the aluminum-containing filter cake in the slurry reach the above range.

[0037] In the present invention, the first solid-liquid separation may include filtration and filter pressing performed in sequence; the filtration may include filter paper filtration or three-stage filtration; the three-stage filtration may include first filtration, second filtration and third filtration performed in sequence; the mesh aperture of the first filtration may be 4-6 mm, and in a specific embodiment, it may be 5 mm; the mesh aperture of the second filtration may be 2-4 mm, and in a specific embodiment, it may be 3 mm; the mesh aperture of the third filtration may be 0.8-2 mm, and in a specific embodiment, it may be 2 mm; the flow rate of the filtration may be 45-55 m / s, and in a specific embodiment, it may be 50 m / s; the feed pressure of the filter pressing may be 1-2 MPa, and in a specific embodiment, it may be 1.5 MPa; the pressing pressure may be 6-10 MPa, and in a specific embodiment, it may be 7 MPa or 9 MPa; the air flow rate of the filter cloth may be 5 L / m 2 ·s or less; the function of the filtration in the present invention is to ensure that the feeding of the filter in the next step is uniform and there is no empty plate phenomenon during high-pressure pressing; the function of the filter press is solid-liquid separation.

[0038] The sodium aluminate solution is obtained. In the present invention, the sodium aluminate solution is mixed with silicon-containing wastewater to perform a precipitation reaction to obtain low-silicon wastewater.

[0039] In the present invention, the concentration of sodium oxide in the sodium aluminate solution can be 10-20 g / L, in a specific embodiment, it can be 12 g / L, 15 g / L or 18 g / L; the concentration of aluminum oxide is 9-15 g / L, in a specific embodiment, it can be 11 g / L or 13 g / L; the ak value is 2-2.3, in a specific embodiment, it can be 2.09 or 2.19; the silicon-containing wastewater can be molecular sieve raw powder washing wastewater; the concentration of silicon dioxide in the silicon-containing wastewater can be 60-2000 mg / L, in a specific embodiment, it can be 1800 mg / L, 1000 mg / L or 220 mg / L; the sodium aluminate solution is Al 2 O 3 The silicon-containing wastewater is SiO 2 The mass ratio can be 0.75 to 1:1, and in a specific embodiment, can be 1:1, 4:5 or 3:4.

[0040] In the present invention, the pH value of the mixture is 8-9; if the pH value of the mixture is not within the above range, the pH value of the silicon-containing wastewater is also adjusted to the above range; limiting the pH value to the above range can achieve better precipitation and silicon removal effects.

[0041] In the present invention, the mixing may further include adding a precipitant; the concentration of the precipitant in the silicon-containing wastewater is 10 to 50 ppm, and in a specific embodiment, it may be 20 ppm, 40 ppm or 50 ppm; the precipitant includes a coagulant and / or a flocculant; the coagulant includes polyaluminium chloride and / or polyferric sulfate; the flocculant includes polyacrylamide; the pH value of the precipitant added is 7 to 8; if the system pH value of the precipitation reaction is not within the above range, the system pH value of the precipitation reaction is adjusted to the above range; limiting the pH value within the above range can optimize the reaction effect of the precipitant, increase the floccules, and better flocculate and settle the particles after the desiliconizer reacts with silicon in the water.

[0042] In the present invention, the concentration of silicon dioxide in the low-silicon wastewater may be below 40 mg / L, and in a specific embodiment, may be 10 mg / L, 20 mg / L or 30 mg / L.

[0043] The comprehensive utilization method provided by the present invention is based on the concept of "treating waste with waste". The aluminum-containing filter cake produced in the production process of molecular sieves is further extracted to remove silicon, which can not only reduce the overall amount of aluminum-containing filter cake, but also reduce water treatment costs. Specifically, the present invention uses the aluminum-containing filter cake after pressure filtration to be pulped again to dissolve the effective component sodium aluminate in the aluminum-containing filter cake, and then obtains a low-concentration sodium aluminate solution through filtration treatment, which can be directly used for wastewater silicon removal, replacing the use of normal silicon removal agents. At the same time, since the concentration of the obtained sodium aluminate solution is relatively low, when used as a silicon removal agent, the dosage can be accurately controlled to reduce the formation of precipitation and reduce the generation of solid waste in the water treatment process.

[0044] Moreover, after the aluminum-containing filter cake is pulped and filtered again, the moisture content of the aluminum-containing filter cake decreases by more than 10%, and the sodium oxide and aluminum oxide in the dry aluminum-containing filter cake decrease by more than 16%, thereby achieving the reduction of the aluminum-containing filter cake. The comprehensive utilization method provided by the present invention fully realizes the resource utilization of the aluminum-containing filter cake and has high economic benefits.

[0045] In order to further illustrate the present invention, the comprehensive utilization method of materials in the production process of zeolite molecular sieve provided by the present invention is described in detail below in conjunction with the accompanying drawings and examples, but they should not be understood as limiting the scope of protection of the present invention.

[0046] Figures 1-2 The following are the existing treatment process of the aluminum-containing filter cake obtained in the molecular sieve production process and the resource utilization process flow chart provided by the present invention. Figures 1-2 It can be seen that the common treatment method is: after the molecular sieve mother liquor reacts with the aluminum hydrogen powder, the aluminum-containing filter cake produced by the filter press is directly collected and transported for disposal, the output is large, and the effective components of sodium ions, hydroxide ions, and aluminum ions are not fully utilized and have no economic value. The resource utilization process provided by the present invention uses the aluminum-containing filter cake after the filter press to be pulped again, so that the effective component sodium aluminate in the aluminum-containing filter cake is dissolved, and then filtered to obtain a sodium aluminate solution, which fully realizes the resource utilization of the aluminum-containing filter cake and has high economic benefits.

[0047] Comparative Example 1

[0048] Add sodium hydroxide liquid alkali into the reactor and start stirring. Add aluminum hydroxide powder according to the ratio. Heat the steam to boiling and keep boiling for more than 3 hours. After the reaction, make up the volume with water and filter it with a filter. The clear liquid is ordinary sodium aluminate desiliconizer.

[0049] Example 1

[0050] A 2L beaker is placed on an electric stove, an asbestos net is placed at the bottom of the beaker, 184.6g of aluminum hydroxide powder (aluminum oxide content is 65%) is added to the beaker, 75.76mL of 330g / L liquid caustic soda and 900mL of FAU-type mother liquor are measured, the sodium oxide content in the mother liquor is 150g / L, and the aluminate content is 8g / L, and they are poured into a beaker, a stirrer is installed on the top of the beaker, uniform stirring is started, the speed is 60rpm, the top is sealed with a plastic wrap, and then the electric stove is turned on for heating; when the liquid in the beaker boils, the frequency of the electric stove is appropriately adjusted to keep the liquid in the beaker in a slightly boiling state, and boiling is continued for 3h (if the water evaporates more than 20%, 150mL of water is added each time); after the double decomposition reaction is completed, the beaker is removed, and after cooling to room temperature, the volume is fixed to 1L, and after stirring evenly, suction filtration is started, and the resulting liquid is a sodium aluminate solution, and the solid is a sodium aluminate aluminum-containing filter cake.

[0051] The sodium aluminate aluminum filter cake was slurried with water in a mass ratio of 1:3, the slurry speed was 60rpm, the time was 1.5h, and the qualitative filter paper was filtered. After filtering, the sodium oxide concentration of the filtrate was 16g / L, the aluminum oxide concentration was 12g / L, and the ak value (the caustic ratio of the silicon removal agent, the molar ratio of sodium oxide to aluminum oxide) was 2.19, that is, the low-concentration sodium aluminate silicon removal agent obtained from the aluminum filter cake. Take the ordinary silicon removal agent (Na 2 O concentration is 164 g / L, Al 2 O 3 The concentration is 124.2 g / L and the ak value is 2.17).

[0052] Take the water from the primary sedimentation tank of the sewage treatment system and measure the silicon content (SiO 2 =219.4mg / L); then take the coagulants PAC (polyaluminium chloride, content is 2%) and PFS (polyferric sulfate, content is 10%), and the flocculant PAM (polyacrylamide, content is 2‰) used on site. According to the different sampling locations, the experiment was divided into three groups, each group took 500mL of water sample, first adjusted the water pH value to 8-9, and then adjusted the mass ratio of SiO 2 :Al 2 O 3 =1:0.75, add desiliconizer, add acid for the second time to adjust the pH to 7-8, add PAC, PAM, PFS, the specific experimental parameters are shown in Table 1, the desiliconization effect data are shown in Table 2, and the actual picture is shown in Figure 3 shown.

[0053] Table 1 Amount of raw materials added in each group of precipitation reactions in Example 1

[0054]

[0055] Table 2 Silicon removal effect data of each group of precipitation reactions in Example 1

[0056]

[0057] From Tables 1 to 2 and Figure 3 It can be seen that the low-concentration sodium aluminate solution prepared by using the aluminum-containing filter cake of sodium aluminate has better silicon removal effect than the ordinary desiliconizer. Therefore, using the sodium aluminate solution obtained by resource utilization of the aluminum-containing filter cake as a desiliconizer can reduce the dosage of the ordinary desiliconizer.

[0058] Example 2

[0059] The process described in Example 1 was scaled up and the low-concentration sodium aluminate desiliconizer prepared from the aluminum-containing filter cake was used for continuous production comparison. The difference was that the solid-liquid separation after the double decomposition reaction was filter press; the feed pressure of the filter press was 0.15MPa, the air pressure was 0.7MPa, and the air blowing was 30min. The solid-liquid separation process after the aluminum-containing filter cake was slurried includes three-stage filtration and filter press. Among them, the mesh aperture of the first filtration is 5mm, the mesh aperture of the second filtration is 3mm, the mesh aperture of the third filtration is 2mm, and the filtration flow rate is 50m / s; the feed pressure of the filter press is 1.5MPa, the pressing pressure is 7MPa, and the air flow rate of the filter cloth is 5L / m 2 ·s. On the first day, the pH value, silicon content, aluminum content changes and agent usage were recorded when using ordinary sodium aluminate desiliconizer; on the second day, the ordinary desiliconizer was replaced with a low-concentration sodium aluminate desiliconizer obtained from an aluminum filter cake, and the same records were made. The experimental data on wastewater desiliconization using ordinary desiliconizers and low-concentration sodium aluminate desiliconizers obtained from aluminum filter cakes are shown in Tables 3 and 4.

[0060] Table 3 Experimental data of wastewater silicon removal using common silicon removal agents

[0061]

[0062] Table 4 Experimental data of wastewater silicon removal using low concentration sodium aluminate silicon removal agent obtained from aluminum filter cake

[0063]

[0064]

[0065] It can be seen from Tables 3 and 4 that, under the condition that the dosage of other agents remains unchanged, both ordinary desiliconizers and low-concentration sodium aluminate can achieve the desiliconization effect; the solute dosage of low-concentration desiliconizers is smaller than that of desiliconizers.

[0066] Application Examples

[0067] The low-concentration sodium aluminate solution obtained from the aluminum-containing filter cake was used as a desiliconizer to replace the ordinary sodium aluminate desiliconizer. The raw material consumption and cost comparison analysis data before and after are shown in Table 5.

[0068] Table 5 Raw material consumption and cost data before and after the low concentration sodium aluminate obtained from the aluminum filter cake is used as a silicon removal agent

[0069]

[0070] It can be seen from Table 5 that the use of low-concentration sodium aluminate solution obtained from aluminum-containing filter cake as a desiliconizer can reduce 4 tons of ordinary sodium aluminate every day. Ordinary sodium aluminate is made by boiling sodium aluminate with liquid alkali and hydrogen aluminum powder. The material cost per ton is only 1,100 yuan, while the sodium aluminate desiliconizer obtained from aluminum-containing filter cake has no material cost. The comprehensive labor and energy consumption costs of the two are similar, and the effects both meet actual production needs.

[0071] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for comprehensive utilization of materials in the production process of zeolite molecular sieves, characterized in that: The following steps are involved: The aluminum-containing filter cake is mixed with water, and pulping and first solid-liquid separation are performed in sequence to obtain a sodium aluminate solution; the mass percentage of sodium aluminate in the aluminum-containing filter cake is 1% to 2%; The sodium aluminate solution and silicon-containing wastewater are mixed to carry out precipitation reaction to obtain low-silicon wastewater; the concentration of silicon dioxide in the silicon-containing wastewater is 60-2000 mg / L; the concentration of silicon dioxide in the low-silicon wastewater is below 40 mg / L.

2. The comprehensive utilization method according to claim 1, characterized in that: The preparation process of the aluminum-containing filter cake comprises the following steps: The molecular sieve mother liquor and aluminum hydrogen powder are mixed, and double decomposition reaction and second solid-liquid separation are carried out in sequence to obtain the aluminum-containing filter cake; the concentration of sodium oxide in the molecular sieve mother liquor is above 110 g / L.

3. The comprehensive utilization method according to claim 2, characterized in that: The molecular sieve mother liquor comprises an LTA type molecular sieve mother liquor, a MOR type molecular sieve mother liquor or a FAU type molecular sieve mother liquor; The mass percentage of aluminum oxide in the aluminum hydrogen powder is more than 60%; the mass ratio of sodium oxide in the molecular sieve mother liquor to aluminum oxide in the aluminum hydrogen powder is 10-20:

1.

4. The comprehensive utilization method according to claim 2 or 3, characterized in that: The temperature of the double decomposition reaction is above 100°C and the time is 3 to 5 hours; The second solid-liquid separation is suction filtration or pressure filtration; the feeding pressure of the pressure filtration is 0.1-0.2 MPa, the air pressure is 0.6-0.8 MPa, and the air blowing time is 25-35 min.

5. The comprehensive utilization method according to claim 1, characterized in that: The mass ratio of the aluminum-containing filter cake to water is 1:2.5-3.5; the particle size of the aluminum-containing filter cake in the slurry obtained by beating is less than 0.175 mm.

6. The comprehensive utilization method according to claim 1 or 5, characterized in that: The beating process is performed at a rotation speed of 50 to 70 rpm and a time of 1 to 2 hours.

7. The comprehensive utilization method according to claim 1, characterized in that: The first solid-liquid separation includes filtration and filter pressing performed in sequence.

8. The comprehensive utilization method according to claim 7, characterized in that: The filtration includes filter paper filtration or three-stage filtration; the three-stage filtration includes first filtration, second filtration and third filtration performed in sequence; the mesh aperture of the first filtration is 4 to 6 mm; the mesh aperture of the second filtration is 2 to 4 mm; the mesh aperture of the third filtration is 0.8 to 2 mm.

9. The comprehensive utilization method according to claim 7, characterized in that: The feed pressure of the filter press is 1-2 MPa, the pressing pressure is 6-10 MPa, and the air flow rate of the filter cloth is 5 L / m 2 ·s or less.

10. The comprehensive utilization method according to claim 1, characterized in that: The sodium aluminate solution is calculated as Al2O3, and the silicon-containing wastewater is calculated as SiO2, and the mass ratio is 0.75 to 1:1.

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