Method for comprehensive utilization of materials in zeolite molecular sieve production process

Abstract

The present application belongs to the technical field of resource recycling, and particularly relates to a comprehensive utilization method of material in a zeolite molecular sieve production process. The present application provides a comprehensive utilization method of material in a zeolite molecular sieve production process, comprising the following steps: mixing an aluminum-containing filter cake and water, and sequentially performing beating and first solid-liquid separation to obtain a sodium metaaluminate solution; the mass percentage of sodium metaaluminate in the aluminum-containing filter cake is 1% to 2%; mixing the sodium metaaluminate solution and silicon-containing wastewater, and performing a precipitation reaction to obtain low-silicon wastewater; the concentration of silicon dioxide in the silicon-containing wastewater is 60 to 2000 mg / L; and the concentration of silicon dioxide in the low-silicon wastewater is 40 mg / L or less. The resource utilization method provided by the present application starts from the concept of 'waste treatment with waste', further extracts effective components from the aluminum-containing filter cake generated in the molecular sieve production process, and is used for silicon removal, which can not only reduce the overall aluminum-containing filter cake amount, but also reduce the water treatment cost.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of resource recycling, and particularly relates to a comprehensive utilization method of materials in a zeolite molecular sieve production process. BACKGROUND

[0002] In the preparation process of the molecular sieve raw powder, a large amount of washing water is used, and the wastewater obtained by washing contains silicon dioxide, which needs to be treated by a membrane system. In order to prevent membrane pollution and blockage, improve the treatment efficiency and stability, and meet the water quality requirements, the silicon dioxide in the wastewater must be removed before entering the membrane system for treatment. The conventional method for removing silicon dioxide is to add a silicon removal agent, such as sodium metaaluminate or magnesium chloride. These agents are used as silicon removal agents at a high cost, accounting for 30-50% of the water treatment cost, and a large amount of inorganic silicon-containing aluminum sludge is also generated.

[0003] On the other hand, the aluminum-containing filter cake produced by pressure filtration after the reaction of the molecular sieve mother liquor with aluminum powder is generally directly collected and transported for disposal, and the treatment amount is large. Therefore, the treatment cost of the aluminum-containing filter cake and the wastewater in the zeolite production process is high. SUMMARY

[0004] The purpose of the present application is to provide a comprehensive utilization method of materials in a zeolite molecular sieve production process. The method provided by the present application recycles the aluminum-containing filter cake obtained in the zeolite production process as a silicon removal agent for silicon-containing wastewater, realizes waste treatment with waste, and reduces the treatment cost of the aluminum-containing filter cake and the wastewater.

[0005] In order to achieve the above-mentioned purpose, the present application provides the following technical scheme:

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

[0007] Mixing the aluminum-containing filter cake and water, and sequentially performing beating and first solid-liquid separation to obtain a sodium metaaluminate solution; the mass percentage of sodium metaaluminate in the aluminum-containing filter cake is 1-2%;

[0008] Mixing the sodium metaaluminate solution and silicon-containing wastewater, and performing a precipitation reaction to obtain low-silicon wastewater; the concentration of silicon dioxide in the silicon-containing wastewater is 60-2000 mg / L; and the concentration of silicon dioxide in the low-silicon wastewater is 40 mg / L or less.

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

[0010] Mixing the molecular sieve mother liquor and aluminum powder, and sequentially performing a double decomposition reaction and second solid-liquid separation to obtain the aluminum-containing filter cake; the concentration of sodium oxide in the molecular sieve mother liquor is 110 g / L or more.

[0011] Preferably, the molecular sieve mother liquor comprises a 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 hydrogen aluminum powder is 60% or more; and the mass ratio of sodium oxide in the molecular sieve mother liquor to aluminum oxide in the hydrogen aluminum powder is 10-20:1.

[0013] Preferably, the temperature of the metathesis reaction is 100℃ or more, and the time is 3-5h.

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

[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 the beating is 0.175mm or less.

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

[0017] Preferably, the first solid-liquid separation comprises filtration and pressure filtration performed in sequence.

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

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

[0020] Preferably, the mass ratio of the sodium metaaluminate solution (calculated as Al2O3) to the silicon-containing wastewater (calculated as SiO2) is 0.75-1:1.

[0021] The application provides a comprehensive utilization method of materials in a zeolite molecular sieve production process, and comprises the following steps: The comprehensive utilization method provided by the application is based on the concept of "treating waste with waste", and further extracts effective components from the aluminum-containing filter cake generated in the molecular sieve production process, so as to remove silicon, reduce the amount of the whole aluminum-containing filter cake, and reduce the water treatment cost. Specifically, the aluminum-containing filter cake after pressure filtration is beaten again, so that the effective component metasilicic acid sodium in the aluminum-containing filter cake is dissolved, and then a low-concentration metasilicic acid sodium solution is obtained through filtration treatment, which can be directly used for wastewater silicon removal and replace the use of normal silicon removal agent. At the same time, since the concentration of the obtained metasilicic acid sodium solution is low, the amount can be accurately controlled when the metasilicic acid sodium solution is used as a silicon removal agent, the generation of precipitates is reduced, and the generation of solid waste in the water treatment process is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description only constitute some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0023] Fig. 1 The existing treatment process flow chart of the aluminum-containing filter cake obtained in the molecular sieve production process;

[0024] Fig. 2 The resource utilization process flow chart of the aluminum-containing filter cake obtained in the molecular sieve production process provided by the application;

[0025] Fig. 3 The silicon removal effect physical map of the metasilicic acid sodium solution obtained from the aluminum-containing filter cake and the normal metasilicic acid sodium solution as the wastewater silicon removal agent in embodiment 1. DETAILED DESCRIPTION

[0026] The application provides a comprehensive utilization method of materials in a zeolite molecular sieve production process, and comprises the following steps:

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

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

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

[0030] The present application mixes the aluminum-containing filter cake and water, and sequentially carries out beating and first solid-liquid separation to obtain a sodium metaaluminate solution.

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

[0032] The present application mixes the molecular sieve mother liquor and aluminum powder, and sequentially carries out a double decomposition reaction and second solid-liquid separation 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 application, the molecular sieve mother liquor can include LTA-type molecular sieve mother liquor, MOR-type molecular sieve mother liquor or FAU-type molecular sieve mother liquor; the concentration of sodium oxide in the molecular sieve mother liquor can be above 110 g / L, and in specific embodiments, can be 150 g / L; the concentration of aluminate can be 5-20 g / L, and in specific embodiments, can be 8 g / L; the mass percentage content of aluminum oxide in the aluminum powder can be above 60%, and in specific embodiments, can be 60%, 64% or 68%; the mass ratio of sodium oxide in the molecular sieve mother liquor to aluminum oxide in the aluminum powder can be 10-20:1, and in specific embodiments, can be 12:1, 15:1 or 18:1; the raw material of the double decomposition reaction further includes a sodium hydroxide solution; the concentration of the sodium hydroxide solution can be 200-500 g / L, and in specific embodiments, can be 250 g / L, 330 g / L or 400 g / L; the volume ratio of the molecular sieve mother liquor to liquid caustic can be 5-20:1, and in specific embodiments, can be 10:1, 12:1 or 15:1.

[0034] In the present application, the temperature of the double decomposition reaction can be above 100℃, and in specific embodiments, can be 100℃, 120℃ or 150℃; the time can be 3-5 h, and in specific embodiments, can be 4 h or 5 h; the double decomposition reaction is carried out under stirring; the stirring speed is 50-70 rpm, and in specific embodiments, can be 60 rpm.

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

[0036] In the present application, the aluminum-containing filter cake is an aluminum-containing filter cake obtained in the molecular sieve production process; the mass percentage of sodium metaaluminate in the aluminum-containing filter cake can be 1%-2%, and in specific embodiments, it can be 1.5%; the mass ratio of the aluminum-containing filter cake to water can be 1:2.5-3.5, and in specific embodiments, it can be 1:3; the particle size of the aluminum-containing filter cake in the slurry obtained by beating can be 0.175 mm or less; the rotation speed of the beating can be 50-70 rpm, and the time can be 1-2 h; 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 application, the first solid-liquid separation can include filtration and pressure filtration performed in sequence; the filtration can include filter paper filtration or three-stage filtration; the three-stage filtration can include first filtration, second filtration, and third filtration performed in sequence; the screen mesh aperture of the first filtration can be 4-6 mm, and in specific embodiments, it can be 5 mm; the screen mesh aperture of the second filtration can be 2-4 mm, and in specific embodiments, it can be 3 mm; the screen mesh aperture of the third filtration can be 0.8-2 mm, and in specific embodiments, it can be 2 mm; the flow rate of the filtration can be 45-55 m / s, and in specific embodiments, it can be 50 m / s; the feeding pressure of the pressure filtration can be 1-2 MPa, and in specific embodiments, it can be 1.5 MPa; the squeezing pressure can be 6-10 MPa, and in specific embodiments, it can be 7 MPa or 9 MPa; the air flow rate of the filter cloth can be 5 L / m 2 ·s or less; in the present application, the filtration is to ensure uniform feeding of the filter, and there is no empty plate phenomenon during high-pressure squeezing; the pressure filtration is for solid-liquid separation.

[0038] After obtaining the sodium metaaluminate solution, the present application mixes the sodium metaaluminate solution with silicon-containing wastewater to perform a precipitation reaction, and obtains low-silicon wastewater.

[0039] In the present application, the concentration of sodium oxide in the sodium metaaluminate solution can be 10-20 g / L, in specific embodiments, it can be 12 g / L, 15 g / L or 18 g / L; the concentration of aluminum oxide is 9-15 g / L, in specific embodiments, it can be 11 g / L or 13 g / L; the ak value is 2-2.3, in specific embodiments, 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 specific embodiments, it can be 1800 mg / L, 1000 mg / L or 220 mg / L; the mass ratio of the sodium metaaluminate solution (calculated as Al2O3) to the silicon-containing wastewater (calculated as SiO2) can be 0.75-1:1, in specific embodiments, it can be 1:1, 4:5 or 3:4.

[0040] In the present application, 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 adjusted to the above range; limiting the pH value within the above range can achieve a better silicon removal effect.

[0041] In the present application, after the mixing, a precipitant can be further added; the concentration of the precipitant in the silicon-containing wastewater is 10-50 ppm, in specific embodiments, it can be 20 ppm, 40 ppm or 50 ppm; the precipitant includes a coagulant and / or a flocculant; the coagulant includes polyaluminum chloride and / or polyferric sulfate; the flocculant includes polyacrylamide; the pH value for adding the precipitant is 7-8; if the pH value of the system for the precipitation reaction is not within the above range, the pH value of the system for the precipitation reaction is adjusted to the above range; limiting the pH value within the above range can make the reaction effect of the precipitant optimal, increase the floc, and better flocculate and settle the particles after the silicon removal agent reacts with silicon in water.

[0042] In the present application, the concentration of silicon dioxide in the low-silicon wastewater can be 40 mg / L or less, in specific embodiments, it can be 10 mg / L, 20 mg / L or 30 mg / L.

[0043] The comprehensive utilization method provided by the present application starts from the concept of "waste treatment with waste", further extracts effective components from the aluminum-containing filter cake generated in the molecular sieve production process, and is used for silicon removal, which can not only reduce the overall amount of aluminum-containing filter cake, but also reduce the water treatment cost. Specifically, the present application uses the aluminum-containing filter cake after pressure filtration to make pulp again, so that the effective component sodium metaaluminate in the aluminum-containing filter cake is dissolved, and then a low-concentration sodium metaaluminate solution is obtained through filtration treatment, which can be directly used for wastewater silicon removal and replace the use of normal silicon removal agent. At the same time, since the obtained sodium metaaluminate solution has a low concentration, the dosage can be accurately controlled when it is applied as a silicon removal agent, the generation of precipitates is reduced, and the generation of solid waste in the water treatment process is reduced.

[0044] And, the aluminum-containing filter cake is pulped again after pressure filtration, the moisture of the aluminum-containing filter cake is reduced by more than 10%, the sodium oxide and aluminum oxide in the dry basis aluminum-containing filter cake are reduced by more than 16%, and the aluminum-containing filter cake is reduced. The comprehensive utilization method provided by the application fully realizes the resource utilization of the aluminum-containing filter cake, and has high economic benefits.

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

[0046] Figs. 1-2 The existing treatment process of the aluminum-containing filter cake obtained in the production process of the molecular sieve and the resource utilization process flowchart provided by the present application are shown in Figures 1 and 2 respectively. Figs. 1-2 As can be seen, the ordinary treatment method is that after the reaction of the molecular sieve mother liquor and the aluminum powder, the aluminum-containing filter cake produced by pressure filtration is directly collected and transported for disposal, and the effective components such as sodium ions, hydroxide ions and aluminum ions in it cannot be fully utilized and have no economic value. The resource utilization process provided by the present application uses the aluminum-containing filter cake after pressure filtration to be pulped again, so that the effective component sodium metaaluminate in the aluminum-containing filter cake is dissolved, and then a sodium metaaluminate solution is obtained after filtration treatment, fully realizing the resource utilization of the aluminum-containing filter cake and having high economic benefits.

[0047] Comparative Example 1

[0048] In the reaction kettle, sodium hydroxide liquid alkali is added, and stirring is started. According to the ratio, aluminum powder is added, and steam is heated to boiling. The boiling is maintained for >3h. After the reaction, water is added to constant volume, and the clear liquid is filtered by a filter. The clear liquid is the ordinary sodium metaaluminate desilication agent.

[0049] Example 1

[0050] A 2L beaker was placed on an electric heating furnace, a stone wool net was placed at the bottom of the beaker, 184.6g of aluminum powder (aluminum oxide content of 65%) was added into the beaker, 75.76mL of 330g / L liquid alkali and 900mL of FAU type steam mother liquor were measured, the sodium oxide content in the mother liquor was 150g / L, and the metaaluminate content was 8g / L, the beaker was poured into the beaker, a stirrer was installed at the top of the beaker, and uniform stirring was started at a speed of 60rpm, the top was sealed with plastic wrap, and then the electric heating furnace was started to heat; when the liquid in the beaker boiled, the frequency of the electric heating furnace was adjusted appropriately to keep the liquid in the beaker in a slightly boiling state, and the boiling was continued for 3h (if the water evaporation exceeds 20%, 150mL of water is added each time); after the metathesis reaction was completed, the beaker was removed, and after the temperature was lowered to room temperature, the volume was constant to 1L, and after stirring was uniform, filtration was started. The obtained liquid is a sodium aluminate solution, and the solid is an aluminum-containing filter cake of sodium aluminate.

[0051] The sodium aluminate containing aluminum filter cake is slurried with water at a mass ratio of 1:3, the slurry is rotated at a speed of 60 rpm for 1.5 h, and then filtered through qualitative filter paper. The concentration of sodium oxide in the filtrate is 16 g / L, the concentration of aluminum oxide is 12 g / L, and the ak value (the molar ratio of caustic to silica removal agent, the molar ratio of sodium oxide to aluminum oxide) is 2.19, i.e. the low-concentration meta-aluminate sodium removal agent obtained from the aluminum-containing filter cake. The ordinary silica removal agent (the concentration of Na2O is 164 g / L, the concentration of Al2O3 is 124.2 g / L, and the ak value is 2.17) is taken.

[0052] The raw water of the primary sedimentation tank of a sewage treatment system is taken, and the silicon content (SiO2=219.4 mg / L) is measured. The coagulant PAC (polyaluminum chloride, content of 2%) and PFS (polyferric sulfate, content of 10%) used on site, and the flocculant PAM (polyacrylamide, content of 2‰) are taken. According to the different sampling locations, three groups of experiments are carried out, and 500 mL of water sample is taken for each group. The pH value of the water is first adjusted to 8-9, the silica removal agent is added according to the mass ratio of SiO2:Al2O3=1:0.75, and then the pH value is adjusted to 7-8 by adding acid again. PAC, PAM and PFS are added. The specific experimental parameters are shown in Table 1, the silica removal effect data are shown in Table 2, and the physical diagram is shown in Fig. 3 .

[0053] Table 1: Raw material addition amount of each group of precipitation reactions in Example 1

[0054]

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

[0056]

[0057] From Tables 1-2 and Fig. 3 It can be seen that the low-concentration meta-aluminate sodium solution prepared from the sodium aluminate containing aluminum filter cake has a better silica removal effect compared with the ordinary silica removal agent, and therefore the meta-aluminate sodium solution obtained by resource utilization of the aluminum-containing filter cake as a silica removal agent can reduce the use amount of the ordinary silica removal agent.

[0058] Example 2

[0059] The process described in Example 1 is scaled up to produce a low concentration meta-aluminate silicon removal agent from the aluminum-containing filter cake for continuous production, with the difference being that the solid-liquid separation after the double decomposition reaction is pressure filtration; the feeding pressure of the pressure filtration is 0.15 MPa, the air pressure is 0.7 MPa, and the air blowing is 30 min. The solid-liquid separation process after the slurry of the aluminum-containing filter cake is filtered includes three stages of filtration and pressure filtration. Among them, the screen mesh size of the first filtration is 5 mm, the screen mesh size of the second filtration is 3 mm, the screen mesh size of the third filtration is 2 mm, and the flow rate of the filtration is 50 m / s; the feeding pressure of the pressure filtration is 1.5 MPa, the squeezing pressure is 7 MPa, and the air flow rate of the filter cloth is 5 L / m 2 On the first day, the pH value, the change in the silicon content, the change in the aluminum content, and the use of the agent when using the ordinary meta-aluminate silicon removal agent are recorded; on the second day, the ordinary silicon removal agent is replaced with the low concentration meta-aluminate silicon removal agent obtained from the aluminum-containing filter cake, and the same records are made. The wastewater silicon removal experimental data of the ordinary silicon removal agent and the low concentration meta-aluminate silicon removal agent obtained from the aluminum-containing filter cake are shown in Tables 3 and 4.

[0060] Table 3 Wastewater silicon removal experimental data of the ordinary silicon removal agent

[0061]

[0062] Table 4 Wastewater silicon removal experimental data of the low concentration meta-aluminate silicon removal agent obtained from the aluminum-containing filter cake

[0063]

[0064]

[0065] As can be seen from Tables 3-4, under the condition that the dosages of other agents remain unchanged, both the ordinary silicon removal agent and the low concentration meta-aluminate silicon removal agent can achieve the effect of silicon removal; the solute dosage of the low concentration silicon removal agent is smaller than that of the silicon removal agent.

[0066] Application Example

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

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

[0069]

[0070] From Table 5, it can be seen that the low-concentration sodium metaaluminate solution obtained from the aluminum-containing filter cake is used as a desiliconizing agent, and 4 tons of ordinary sodium metaaluminate can be reduced per day. The ordinary sodium metaaluminate is prepared by using liquid caustic soda and aluminum powder to boil sodium metaaluminate, and the material cost of each ton is only 1100 yuan. The desiliconizing agent of sodium metaaluminate obtained from the aluminum-containing filter cake has no material cost, the comprehensive cost of labor and energy consumption is close, and the effects of both meet the actual production requirements.

[0071] Although the above embodiments have made a detailed description of the present application, it is only a part of the embodiments of the present application, not all the embodiments, and other embodiments can be obtained under the premise of no creativity according to the present embodiments, and these embodiments all belong to the protection scope of the present application.

Claims

1. A method for comprehensive utilization of materials in the production process of zeolite molecular sieves, characterized in that, Includes the following steps: The aluminum-containing filter cake is mixed with water, and then subjected to slurrying 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%~2%. The sodium aluminate solution and silicon-containing wastewater are mixed and subjected to a precipitation reaction to obtain low-silicon wastewater; the silicon-containing wastewater is molecular sieve raw powder washing wastewater; the pH value of the mixture is 8-9; the pH value of the precipitation reaction is 7-8; the concentration of silica in the silicon-containing wastewater is 60-2000 mg / L; the concentration of silica in the low-silicon wastewater is below 40 mg / L. 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 pulp obtained by pulping is less than 0.175mm; The preparation process of the aluminum-containing filter cake includes the following steps: The molecular sieve mother liquor and aluminum hydroxide powder are mixed and subjected to a metathesis reaction and a second solid-liquid separation to obtain the aluminum-containing filter cake; the concentration of sodium oxide in the molecular sieve mother liquor is above 110 g / L. The molecular sieve mother liquor includes LTA type molecular sieve mother liquor, MOR type molecular sieve mother liquor or FAU type molecular sieve mother liquor; The aluminum hydroxide powder contains more than 60% alumina by mass; the mass ratio of sodium oxide in the molecular sieve mother liquor to alumina in the aluminum hydroxide powder is 10~20:

1.

2. The comprehensive utilization method according to claim 1, characterized in that, The temperature of the metathesis reaction is above 100℃, and the time is 3~5h; The second solid-liquid separation is vacuum filtration or pressure filtration; the feeding pressure of the pressure filtration is 0.1~0.2MPa, the air pressure is 0.6~0.8MPa, and the air blowing time is 25~35min.

3. The comprehensive utilization method according to claim 1, characterized in that, The pulping speed is 50~70 rpm, and the time is 1~2 hours.

4. The comprehensive utilization method according to claim 1, characterized in that, The first solid-liquid separation includes sequential filtration and pressure filtration.

5. The comprehensive utilization method according to claim 4, characterized in that, The filtration includes filter paper filtration or three-stage filtration; the three-stage filtration includes a first filtration, a second filtration, and a third filtration performed sequentially; the screen aperture of the first filtration is 4~6mm; the screen aperture of the second filtration is 2~4mm; and the screen aperture of the third filtration is 0.8~2mm.

6. The comprehensive utilization method according to claim 4, characterized in that, The feed pressure of the filter press is 1~2MPa, the pressing pressure is 6~10MPa, and the air passage of the filter cloth is 5L / m. 2 Below s.

7. 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, with a mass ratio of 0.75 to 1:1.

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