Method for removing deposited carbon in organic silicon waste contact and slurry slag through ultrasonic-assisted reverse flotation

Abstract

The invention discloses a method for removing deposited carbon in organic silicon waste contact bodies and slurry residues through ultrasonic-assisted reverse flotation, and belongs to the technical field of resource circulation and environmental protection. Comprising the following steps: (1) adding water into waste contact bodies or slurry residues to prepare slurry; (2) performing ultrasonic treatment on the slurry; (3) adding carbon capture flotation oil; (4) reverse flotation decarburization; and (5) carrying out solid-liquid separation and drying. According to the method, the deposited carbon on the organic silicon waste contact and the slurry residues is effectively separated from the surfaces of silicon and copper particles through the ultrasonic effect, then separation of the deposited carbon is achieved through the reverse flotation method, the carbon removal efficiency is high, production water can be recycled, and the production cost is low.

Description

Technical Field

[0001] The invention belongs to the technical field of resource recycling and environmental protection, and in particular relates to a method for removing carbon deposits in waste organic silicon contacts and pulp residues by ultrasonic-assisted reverse flotation. Background Art

[0002] Silicone monomers are important raw materials for synthesizing silicone materials. The most widely used monomer is dimethylchlorosilane (M2). At present, the industrial production of M2 mainly adopts the "direct synthesis method", that is, industrial silicon powder and methyl chloride are used as raw materials, copper compounds are used as catalysts, and a methylchlorosilane mixture mainly composed of M2 is synthesized under certain temperature and pressure conditions in a fluidized bed reactor, and then M2 is separated from other by-products by distillation and other methods. In the direct synthesis process, in order to maintain stable production, some unreacted raw materials and inactivated catalysts need to be discharged from the reactor. In this process, two types of hazardous solid wastes will be generated, namely waste contacts and pulp residues.

[0003] The main components of waste contacts and slurry are unreacted silicon powder and copper, and they also contain a certain amount of metal impurities such as Fe and deposited carbon. The deposited carbon in waste contacts and slurry is often one of the reasons that limit their secondary utilization. The removal of deposited carbon in waste contacts and slurry can effectively broaden the scope of secondary utilization of waste contacts and slurry. Chinese patent document CN114349010A discloses a method for removing carbon from waste silicon powder after copper extraction. The main process is to add a cleaning liquid to the waste silicon powder after copper extraction, stir it thoroughly, let it stand and settle, and wash the lower precipitate with water and dry it. This process is simple and feasible, but there is a problem of low carbon removal efficiency, and some deposited carbon still adheres to silicon powder or copper powder particles. Chinese patent document CN117416963A discloses a method for preparing silicon powder from waste silicone contacts, including six steps of decoppering, slurry preparation, two-stage magnetic separation, roasting, pickling, and drying to obtain silicon powder with higher purity. This method effectively removes the impurity Fe in the waste contact and removes the deposited carbon by roasting, but it has problems such as long process and large silicon powder loss. Summary of the invention

[0004] In order to solve the above technical problems, the present invention proposes a method for removing carbon deposits in waste organic silicon contacts and pulp by ultrasonic assisted reverse flotation. The method can reduce the carbon content in waste contacts and pulp to below 0.2%, providing conditions for the secondary utilization of waste contacts and pulp.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for removing carbon deposits in waste organosilicon contacts and pulp residues by ultrasonic-assisted reverse flotation comprises the following steps:

[0007] Put the waste contact body or pulp residue into the flotation tank, add water and stir to obtain slurry;

[0008] The slurry is simultaneously heated, ultrasonically and mechanically stirred to obtain a treated slurry;

[0009] The carbon capture flotation oil is added to the treated slurry under stirring, and then compressed air is introduced from the bottom of the flotation tank to perform reverse flotation operation, solid-liquid separation, and the obtained solid is vacuum dried to obtain low-carbon waste contact or low-carbon pulp residue.

[0010] Furthermore, the amount of water injected is based on the content of waste contact bodies or pulp residues in the slurry being 20-70wt%.

[0011] Furthermore, the specific parameters of the heating, ultrasound and mechanical stirring are: ultrasonic power 200-2000W, ultrasonic frequency 25-40kHz, mechanical stirring speed 2-10r / min, processing time 20-300min, heating temperature 20-80°C.

[0012] Furthermore, the carbon capture flotation oil is one or more of terpineol, kerosene, diesel, 2# engine oil and thiomonoglyceride.

[0013] Furthermore, based on the mass of the slurry, the added amount of the carbon capture flotation oil is 100-1000 g / t.

[0014] Furthermore, the flow rate of the compressed air is 0.1-5.0 L / min; and the reverse flotation time is 5-60 min.

[0015] Furthermore, during the reverse flotation operation, the froth scraping operation is performed every 5-150 seconds.

[0016] The principle of ultrasonic-assisted reverse flotation to remove deposited carbon from waste silicone contacts and pulp residues: When ultrasonic waves propagate in liquids, a large number of cavitation bubbles will be generated. When the cavitation bubbles suddenly close, they will exert a strong force on the surface of solid particles, destroying the adsorption of deposited carbon on the surface of silicon and copper particles, thereby causing the deposited carbon to fall off the surface of silicon and copper particles. After adding carbon-capturing flotation oil, the deposited carbon is enriched by the carbon-capturing flotation oil because the affinity between carbon and oil is greater than that of water, and is migrated to the liquid surface under the action of water buoyancy.

[0017] Compared with the prior art, the present invention has the following advantages and technical effects:

[0018] (1) Short production cycle and high carbon removal efficiency. A large amount of carbon-containing waste contacts and pulp residue can be processed in a short time. The carbon content in the waste contacts and pulp residue after treatment is less than 0.2wt%, and the carbon removal rate exceeds 90%;

[0019] (2) It does not involve high-temperature reactions, has low production energy consumption, and the production water can be recycled, and the production process does not generate large amounts of wastewater discharge;

[0020] (3) The reagent consumption is small, effectively reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0022] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0023] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0024] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0025] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0026] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0027] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0028] The present invention discloses a method for removing carbon deposits from waste organosilicon contacts and pulp residues by ultrasonic-assisted reverse flotation, comprising the following steps: (1) adding water to the waste contacts or pulp residues to form a slurry; (2) ultrasonically treating the slurry; (3) adding carbon-capturing flotation oil; (4) reverse flotation decarbonization; (5) solid-liquid separation and drying. The method utilizes ultrasonic action to effectively separate the carbon deposits on the waste organosilicon contacts and pulp residues from the surface of silicon and copper particles, and then utilizes the reverse flotation method to separate the carbon deposits. The carbon removal efficiency is high, the production water can be recycled, and the production cost is low. The specific technical scheme is as follows:

[0029] S1. Put a certain amount of waste contact bodies or pulp residue into a flotation tank equipped with ultrasonic and mechanical stirring devices, inject water into the flotation tank and stir it thoroughly to obtain slurry;

[0030] S2, turning on the ultrasonic device and assisting the mechanical stirring to ultrasonically treat the slurry and heat the slurry at the same time;

[0031] S3, adding carbon capture flotation oil to the slurry treated in step S2 under mechanical stirring conditions;

[0032] S4, introduce compressed air from the bottom of the flotation tank to perform reverse flotation, and scrape off the foam on the slurry surface at intervals;

[0033] S5, separating the slurry obtained in step S4 into solid and liquid, and vacuum drying the solid to obtain low-carbon waste contact or low-carbon slurry residue.

[0034] In the following preferred embodiment of the present invention, step S1, the content of waste contact bodies or pulp residue in the slurry is 20-70wt%.

[0035] In the following preferred embodiment step S2 of the present invention, the ultrasonic power is 200-2000 W, the ultrasonic frequency is 25-40 kHz, the mechanical stirring speed is 2-10 r / min, the processing time is 20-300 min, and the heating temperature is 20-80°C.

[0036] In the following preferred embodiment of the present invention, step S3, the carbon capture flotation oil is one or more of terpineol, kerosene, diesel, 2# engine oil and thiomonoglyceride, such as terpineol and kerosene composite, with a mass ratio of 1: 1. The addition amount of the carbon capture flotation oil is 100-1000 g / t based on the mass of the slurry.

[0037] In the following preferred embodiment of the present invention, in step S4, the flow rate of the compressed air is 0.1-5.0 L / min, the reverse flotation time is 5-60 min, and during the reverse flotation operation, the froth scraping operation is performed every 5-150 s.

[0038] In the following preferred embodiment of the present invention, in step S5, the liquid obtained by solid-liquid separation can be returned to step S1 for slurry preparation.

[0039] Unless otherwise specified, all reagents and raw materials used in the present invention are commercially available products or products that can be prepared by known methods.

[0040] The content of deposited carbon in the waste contactors treated in the following examples was 4.63 wt %, and the content of deposited carbon in the slurry was 9.77 wt %.

[0041] The technical solution of the present invention is further illustrated by the following embodiments.

[0042] Example 1

[0043] A method for removing carbon deposits from waste organic silicon contacts by ultrasonic-assisted reverse flotation, comprising the following steps:

[0044] 1) 100 kg of waste contact bodies were placed in a flotation tank equipped with an ultrasonic and mechanical stirring device, water was injected into the flotation tank and stirred sufficiently to obtain a slurry with a solid content of 20 wt%;

[0045] 2) Turn on the ultrasonic device and assist mechanical stirring, and heat at the same time, the specific parameters are: ultrasonic power 200W, ultrasonic frequency 25kHz, mechanical stirring speed 2r / min, processing time 20min, heating temperature 20°C;

[0046] 3) Under mechanical stirring (stirring speed 2r / min), 100g / t of kerosene was added to the slurry treated in step 2) based on the mass of the slurry in step 1);

[0047] 4) Compressed air is introduced from the bottom of the flotation tank to perform reverse flotation. The compressed air flow rate is 0.1L / min. The froth is scraped off every 5s. The reverse flotation time is 5min.

[0048] 5) The slurry obtained in step 4) is separated into solid and liquid, and the solid is vacuum dried to obtain a low-carbon waste contact body.

[0049] According to the test, the carbon content in the waste contact body after being treated by the above process is 0.051wt%, and the removal rate is 89%.

[0050] Example 2

[0051] A method for removing carbon deposits from waste organic silicon contacts by ultrasonic-assisted reverse flotation, comprising the following steps:

[0052] 1) 1000 kg of waste contact bodies were placed in a flotation tank equipped with an ultrasonic and mechanical stirring device, water was injected into the flotation tank and stirred sufficiently to obtain a slurry with a solid content of 70 wt%;

[0053] 2) Turn on the ultrasonic device and assist mechanical stirring, and heat at the same time, the specific parameters are: ultrasonic power 2000W, ultrasonic frequency 40kHz, mechanical stirring speed 10r / min, processing time 300min, heating temperature 80°C;

[0054] 3) Under mechanical stirring (stirring speed 10 r / min), 1000 g / t of diesel was added to the slurry treated in step 2) based on the mass of the slurry in step 1);

[0055] 4) Compressed air is introduced from the bottom of the flotation tank to perform reverse flotation. The compressed air flow rate is 5.0 L / min. The froth is scraped off every 150 seconds. The reverse flotation time is 60 minutes.

[0056] 5) The slurry obtained in step 4) is separated into solid and liquid, and the solid is vacuum dried to obtain a low-carbon waste contact body.

[0057] According to the test, the carbon content in the waste contact body after being treated by the above process is 0.12wt%, and the removal rate is 97%.

[0058] Example 3

[0059] A method for removing carbon deposits from waste organic silicon contacts by ultrasonic-assisted reverse flotation, comprising the following steps:

[0060] 1) 500 kg of waste contact bodies are placed in a flotation tank equipped with an ultrasonic and mechanical stirring device, water is injected into the flotation tank and stirred sufficiently to obtain a slurry with a solid content of 50 wt%;

[0061] 2) Turn on the ultrasonic device and assist mechanical stirring, and heat at the same time, the specific parameters are: ultrasonic power 1000W, ultrasonic frequency 35kHz, mechanical stirring speed 8r / min, processing time 150min, heating temperature 50°C;

[0062] 3) Under mechanical stirring (stirring speed 8r / min), 600g / t of carbon capture flotation oil (mixed by pine alcohol and kerosene in a mass ratio of 1:1) was added to the slurry treated in step 2) based on the mass of the slurry in step 1);

[0063] 4) Compressed air is introduced from the bottom of the flotation tank to perform reverse flotation operation. The compressed air flow rate is 1.5L / min. The froth is scraped off every 60s. The reverse flotation time is 30min.

[0064] 5) The slurry obtained in step 4) is separated into solid and liquid, and the solid is vacuum dried to obtain a low-carbon waste contact body.

[0065] According to the test, the carbon content in the waste contact body after being treated by the above process is 0.10wt%, and the removal rate is 98%.

[0066] Example 4

[0067] The same as Example 1, except that the waste contact body and the like in step 1) are replaced by pulp residue.

[0068] According to the test, the carbon content in the low-carbon pulp residue after treatment by the above process is 0.18wt%, and the removal rate is 98%.

[0069] Example 5

[0070] Same as Example 2, except that the waste contact bodies in step 1) are replaced with pulp residue.

[0071] According to the test, the carbon content in the low-carbon pulp residue after being treated by the above process is 0.15wt%, and the removal rate is 98%.

[0072] Example 6

[0073] A method for removing deposited carbon in organosilicon slurry by ultrasonic-assisted reverse flotation comprises the following steps:

[0074] 1) 500 kg of pulp residue was loaded into a flotation tank equipped with an ultrasonic and mechanical stirring device, water was injected into the flotation tank and stirred sufficiently to obtain a slurry with a solid content of 50 wt%;

[0075] 2) Turn on the ultrasonic device and assist mechanical stirring, and heat at the same time, the specific parameters are: ultrasonic power 1500W, ultrasonic frequency 30kHz, mechanical stirring speed 6r / min, processing time 120min, heating temperature 50°C;

[0076] 3) Under mechanical stirring (stirring speed 6r / min), 550g / t of carbon capture flotation oil (mixed by pine alcohol and kerosene in a mass ratio of 1:1) was added to the slurry treated in step 2) based on the mass of the slurry in step 1);

[0077] 4) Compressed air is introduced from the bottom of the flotation tank to perform reverse flotation operation. The compressed air flow rate is 2.0L / min. The froth is scraped off every 30s. The reverse flotation time is 30min.

[0078] 5) The slurry obtained by the treatment in step 4) is separated into solid and liquid, and the solid is vacuum dried to obtain low-carbon slurry residue.

[0079] According to the test, the carbon content in the pulp residue after the above process is 0.08wt%, and the removal rate is 99%.

[0080] Comparative Example 1

[0081] Same as Example 3, except that in step 2), the slurry is no longer subjected to ultrasonic treatment, and only mechanical stirring and heating operations are retained.

[0082] According to the test, the carbon content in the waste contact body after being treated by the above process is 1.7wt%, and the removal rate is 63%.

[0083] Comparative Example 2

[0084] Same as Example 6, except that the ultrasonic frequency is 20 kHz.

[0085] According to the test, the carbon content in the pulp residue after the above process is 1.23wt%, and the removal rate is 87%.

[0086] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for removing carbon deposits from waste organic silicon contacts and pulp residues by ultrasonic-assisted reverse flotation. It is characterized in that The following steps are involved: Put the waste contact body or pulp residue into the flotation tank, add water and stir to obtain slurry; The slurry is simultaneously heated, ultrasonically and mechanically stirred to obtain a treated slurry; The carbon capture flotation oil is added to the treated slurry under stirring, and then compressed air is introduced from the bottom of the flotation tank to perform reverse flotation operation, solid-liquid separation, and the obtained solid is vacuum dried to obtain low-carbon waste contact or low-carbon pulp residue.

2. The method for removing carbon deposits from waste organic silicon contacts and pulp residues by ultrasonic-assisted reverse flotation according to claim 1, It is characterized in that The amount of water injected is based on the content of waste contact bodies or pulp residues in the slurry being 20-70wt%.

3. The method for removing carbon deposits from waste organic silicon contacts and pulp residues by ultrasonic-assisted reverse flotation according to claim 1, It is characterized in that The specific parameters of the heating, ultrasound and mechanical stirring are: ultrasound power 200-2000W, ultrasound frequency 25-40kHz, mechanical stirring speed 2-10r / min, processing time 20-300min, heating temperature 20-80°C.

4. The method for removing carbon deposits from waste organic silicon contacts and pulp residues by ultrasonic-assisted reverse flotation according to claim 1, It is characterized in that The carbon capture flotation oil is one or more of terpineol, kerosene, diesel, 2# engine oil and thiomonoglyceride.

5. The method for removing carbon deposits from waste organic silicon contacts and pulp residues by ultrasonic-assisted reverse flotation according to claim 1, It is characterized in that Calculated on the basis of slurry mass, the added amount of the carbon capture flotation oil is 100-1000 g / t.

6. The method for removing carbon deposits from waste organic silicon contacts and pulp residues by ultrasonic-assisted reverse flotation according to claim 1, It is characterized in that The flow rate of the compressed air is 0.1-5.0 L / min; the reverse flotation operation time is 5-60 min.

7. The method for removing carbon deposits from waste organic silicon contacts and pulp residues by ultrasonic-assisted reverse flotation according to claim 1, It is characterized in that During the reverse flotation operation, the froth scraping operation is performed every 5-150 seconds.

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