Efficient suction filtration method for rhenium-containing leachate
By adding activated alumina to the rhenium-containing leachate for pretreatment, and combining static separation and multi-layer filtration, the problem of filter clogging was solved, achieving efficient filtration of the rhenium-containing leachate and improving the rhenium recovery efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-30
- Publication Date
- 2026-03-13
AI Technical Summary
During the filtration process of rhenium-containing leachate, severe clogging of the filter bed leads to low filtration efficiency and affects the efficient recovery of rhenium.
Activated alumina was used as a filter aid for pretreatment. Combined with static separation, vacuum filtration, and centrifugation, the supernatant and turbid sediment were treated separately. The high specific surface area and surface hydroxyl groups of activated alumina were used to capture colloidal particles and form flocs. The filter was then filtered using a filter layer composed of staggered filter cloth and filter paper.
It significantly improves filtration efficiency, shortens filtration time, and ensures the clarity of the filtrate and the removal of fine particles.
Smart Images
Figure CN121653386A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of rhenium-containing leachate filtration technology, specifically to a highly efficient filtration method for rhenium-containing leachates. Background Technology
[0002] Rhenium, a rare element in the Earth's crust, is a key material in the production of single-crystal blades for aero-engines and is hailed as the "crown jewel of modern industry." Recovering rhenium from rhenium-containing flue ash is beneficial for expanding economic benefits. The recovery process involves the filtration of the rhenium-containing leachate. In the later stages of filtration, the residue trapped on the filter bed becomes a viscous, muddy substance, making it difficult to continue extracting the liquid quickly. This, coupled with the clogging of the filter bed by the muddy material, severely restricts filtration efficiency and hinders the efficient recovery of rhenium. Therefore, a highly efficient filtration method for rhenium-containing leachate is proposed. Summary of the Invention
[0003] To address the shortcomings of existing technologies, this invention provides a highly efficient filtration method for rhenium-containing leachate. By pretreating with activated alumina and then allowing the supernatant and turbid sediment to settle and filter separately, the filtration efficiency is significantly improved.
[0004] To achieve the above objectives, the present invention provides the following technical solution: a highly efficient filtration method for rhenium-containing leachate, comprising the following steps: (1) Add a filter aid to the rhenium-containing leachate, stir the mixture evenly to obtain a pretreated rhenium-containing leachate; (2) The pretreated rhenium-containing leachate is injected into a temporary storage tank and separated by settling to form a supernatant and a sediment. (3) The supernatant is drawn into a vacuum filter for vacuum filtration; (4) The settled turbid liquid is pumped into a centrifuge for centrifugal separation, and then the separated liquid is pumped into a vacuum filter for vacuum filtration. The two filtrates are combined.
[0005] Preferably, in step (1), the filter aid is activated alumina with a particle size of 1-10 μm.
[0006] Preferably, in step (1), the content of the active alumina in the pretreated rhenium-containing leachate is 1-5% w / v.
[0007] Preferably, in step (2), the pretreated rhenium-containing leachate is left to stand in the storage tank for more than 12 hours.
[0008] Preferably, in step (3), the filter layer of the vacuum filter is composed of filter cloth and filter paper stacked in a staggered manner.
[0009] Preferably, the filter cloth has a mesh count of 2000 and the filter paper has a pore size of 11μm.
[0010] Preferably, the filter cloth has two layers and the filter paper has two layers.
[0011] Preferably, in step (3), the vacuum filtration time is 5 minutes and the vacuum filtration pressure is -0.08 MPa.
[0012] Preferably, in step (4), the centrifuge rotates at 2000 rpm and the centrifugation time is 10 min.
[0013] Preferably, in step (4), the vacuum filtration time is 25 seconds and the vacuum filtration pressure is -0.08 MPa.
[0014] This invention provides a highly efficient filtration method for rhenium-containing leachate, which has the following advantages compared with the prior art: This invention uses activated alumina for pretreatment, combined with static filtration of the supernatant and turbid sediment, which significantly improves filtration efficiency and shortens filtration time. The present invention pre-adds activated alumina to rhenium-containing leachate, which has a high specific surface area and abundant surface hydroxyl groups, and can capture colloidal particles through electrostatic adsorption or coordination bonding to form larger flocs, which facilitates subsequent filtration. The filter layer in this invention is composed of alternating filter cloth and filter paper. The filter cloth layer intercepts most of the sediment, and a small number of fine particles that pass through the filter cloth are further intercepted by the filter paper, thus improving the filtration effect. Attached Figure Description
[0015] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a flow chart of the rhenium-containing leachate filtration process of the present invention; Figure 2 This is a schematic diagram of the filter layer structure of the present invention; Figure 3 This is a diagram of the filtrate product from Example 1 of the present invention; Figure 4 This is a diagram of the filtrate product from Comparative Example 2 of the present invention. Detailed Implementation
[0016] The following embodiments are provided to illustrate the implementation of this application in detail, so that the process of how this application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.
[0017] The reason why the filtration time in this invention needs to exclude the settling and separation time in the temporary storage tank is that several temporary storage tanks can be set up to perform the settling and separation process in advance.
[0018] Example 1 A highly efficient filtration method for rhenium-containing leachate includes the following steps: (1) Add activated alumina (particle size 1-10μm) to 100L of rhenium-containing leachate (rhenium content 0.82g / L), stir and react evenly to obtain pretreated rhenium-containing leachate; wherein the content of activated alumina in the pretreated rhenium-containing leachate is 2%w / v; (2) The pretreated rhenium-containing leachate is injected into a temporary storage tank and allowed to stand for more than 12 hours to form a supernatant and a sediment. (3) The supernatant was drawn into a vacuum filter and vacuum filtered for 5 minutes at a pressure of -0.08 MPa. The filter layer of the vacuum filter was composed of filter cloth and filter paper stacked in an alternating manner. The filter cloth had a mesh size of 2000 mesh and the filter paper had a pore size of 11 μm. There were two layers of filter cloth and two layers of filter paper. (4) The settled turbid liquid is drawn into a centrifuge for centrifugation at 2000 rpm for 10 min. Then the separated liquid is drawn into a vacuum filter and vacuum filtered for 25 min at a pressure of -0.08 MPa. The two filtrates are combined.
[0019] The relevant parameters in this embodiment are shown in Table 1.
[0020] Table 1. Parameters related to filtration Upon observation, the filtrate was found to be clear, with no visible fine particles.
[0021] Comparative Example 1 A highly efficient filtration method for rhenium-containing leachate includes the following steps: (1) 100L of rhenium-containing leachate (containing 0.82g / L of rhenium) was injected into a temporary storage tank and allowed to stand for more than 12 hours to separate into a supernatant and a sediment. (2) The supernatant was drawn into a vacuum filter and vacuum filtered for 5 minutes at a pressure of -0.08 MPa. The filter layer of the vacuum filter was composed of filter cloth and filter paper stacked in an alternating manner. The filter cloth had a mesh size of 2000 mesh and the filter paper had a pore size of 11 μm. There were two layers of filter cloth and two layers of filter paper. (3) The settled turbid liquid was drawn into a centrifuge for centrifugation at 2000 rpm for 10 min. The resulting separated liquid was then drawn into a vacuum filter and vacuum filtered for 45 min at a pressure of -0.08 MPa. The two filtrates were then combined.
[0022] The relevant parameters in this comparative example are shown in Table 2.
[0023] Table 2 Parameters related to filtration As shown in Table 2, compared with Example 1, it is more difficult to filter the precipitated turbid liquid without adding activated alumina; observation showed that the filtrate was clear and there were no fine particles visible.
[0024] Comparative Example 2 A highly efficient filtration method for rhenium-containing leachate includes the following steps: (1) Add activated alumina to 100L of rhenium-containing leachate (containing 0.82g / L of rhenium), stir and react evenly to obtain a pretreated rhenium-containing leachate; wherein the content of activated alumina in the pretreated rhenium-containing leachate is 2%w / v; (2) The pretreated rhenium-containing leachate is injected into a temporary storage tank and allowed to stand for more than 12 hours to form a supernatant and a sediment. (3) The supernatant is drawn into a vacuum filter and vacuum filtered for 5 minutes at a pressure of -0.08 MPa. The filter layer of the vacuum filter is made of filter cloth. The mesh size of the filter cloth is 2000 mesh. There are two layers of filter cloth. (4) The settled turbid liquid is drawn into a centrifuge for centrifugation at 2000 rpm for 10 min. The resulting separated liquid is then drawn into a vacuum filter and vacuum filtered for 24 min at a pressure of -0.08 MPa. The two filtrates are then combined.
[0025] The relevant parameters in this comparative example are shown in Table 3.
[0026] Table 3. Parameters related to filtration: As shown in Table 3, compared with Example 1, the filter layer only used filter cloth, which did not affect the filtration efficiency; however, it was observed that there were still a small number of fine particles in the filtrate, and the filtration effect was not good.
[0027] Comparative Example 3 A highly efficient filtration method for rhenium-containing leachate includes the following steps: (1) Add activated alumina to 100L of rhenium-containing leachate (containing 0.82g / L of rhenium), stir and react evenly to obtain a pretreated rhenium-containing leachate; wherein the content of activated alumina in the pretreated rhenium-containing leachate is 2%w / v; (2) The pretreated rhenium-containing leachate was drawn into a vacuum filter and vacuum filtered for 90 minutes at a pressure of -0.08 MPa to obtain the filtrate. The filter layer of the vacuum filter was composed of filter cloth and filter paper stacked in a staggered manner. The filter cloth had a mesh size of 2000 mesh and the filter paper had a pore size of 11 μm. There were two layers of filter cloth and two layers of filter paper.
[0028] The relevant parameters in this comparative example are shown in Table 4.
[0029] Table 4. Parameters related to filtration: As shown in Table 4, compared with Example 1, the filtration time used in this comparative example was significantly longer when achieving a similar volume of filtrate. Observation revealed that the filtrate was clear and there were no fine particles visible to the naked eye.
[0030] Comparative Example 4 A method for filtration of rhenium-containing leachate: The rhenium-containing leachate is drawn into a vacuum filter and vacuum filtered for 140 minutes at a pressure of -0.08 MPa to obtain the filtrate; the filter layer of the vacuum filter is composed of filter cloth. The filter cloth has a mesh size of 2000 mesh and consists of two layers.
[0031] The relevant parameters in the comparative example are shown in Table 5.
[0032] Table 5. Parameters related to filtration: As shown in Table 5, compared with Example 1, the filtration time used in this comparative example was significantly longer when achieving a similar volume of filtrate, and the filtration time was much longer. It was also observed that there were still a small number of fine particles in the filtrate.
[0033] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A highly efficient filtration method for rhenium-containing leachate, characterized in that, Includes the following steps: (1) Add a filter aid to the rhenium-containing leachate, stir the mixture evenly to obtain a pretreated rhenium-containing leachate; (2) The pretreated rhenium-containing leachate is injected into a temporary storage tank and separated by settling to form a supernatant and a sediment. (3) The supernatant is drawn into a vacuum filter for vacuum filtration; (4) The settled turbid liquid is pumped into a centrifuge for centrifugal separation, and then the separated liquid is pumped into a vacuum filter for vacuum filtration. The two filtrates are combined.
2. The efficient filtration method for rhenium-containing leachate according to claim 1, characterized in that, In step (1), the filter aid is activated alumina with a particle size of 1-10 μm.
3. The efficient filtration method for rhenium-containing leachate according to claim 2, characterized in that, In step (1), the content of the activated alumina in the pretreated rhenium-containing leachate is 1-5% w / v.
4. The efficient filtration method for rhenium-containing leachate according to claim 1, characterized in that, In step (2), the pretreated rhenium-containing leachate is left to stand in the temporary storage tank for more than 12 hours.
5. The efficient filtration method for rhenium-containing leachate according to claim 1, characterized in that, In step (3), the filter layer of the vacuum filter is composed of filter cloth and filter paper stacked in a staggered manner.
6. The efficient filtration method for rhenium-containing leachate according to claim 5, characterized in that, The filter cloth has a mesh count of 2000 and the filter paper has a pore size of 11μm.
7. The efficient filtration method for rhenium-containing leachate according to claim 5, characterized in that, The filter cloth has two layers, and the filter paper has two layers.
8. The efficient filtration method for rhenium-containing leachate according to claim 1, characterized in that, In step (3), the vacuum filtration time is 5 minutes and the vacuum filtration pressure is -0.08 MPa.
9. The efficient filtration method for rhenium-containing leachate according to claim 1, characterized in that, In step (4), the centrifuge rotates at 2000 rpm and the centrifugation time is 10 min.
10. The efficient filtration method for rhenium-containing leachate according to claim 1, characterized in that, In step (4), the vacuum filtration time is 25 minutes and the vacuum filtration pressure is -0.08 MPa.