CN115286417A - Recycling method of honeycomb ceramic waste - Google Patents
Recycling method of honeycomb ceramic waste Download PDFInfo
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- CN115286417A CN115286417A CN202210962510.1A CN202210962510A CN115286417A CN 115286417 A CN115286417 A CN 115286417A CN 202210962510 A CN202210962510 A CN 202210962510A CN 115286417 A CN115286417 A CN 115286417A
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B38/00—Porous mortars, concrete, artificial stone or ceramic ware; Preparation thereof
- C04B38/0006—Honeycomb structures
- C04B38/0009—Honeycomb structures characterised by features relating to the cell walls, e.g. wall thickness or distribution of pores in the walls
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- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
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- C04B33/00—Clay-wares
- C04B33/02—Preparing or treating the raw materials individually or as batches
- C04B33/13—Compounding ingredients
- C04B33/1305—Organic additives
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B33/00—Clay-wares
- C04B33/02—Preparing or treating the raw materials individually or as batches
- C04B33/13—Compounding ingredients
- C04B33/132—Waste materials; Refuse; Residues
- C04B33/1324—Recycled material, e.g. tile dust, stone waste, spent refractory material
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- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
- C04B2235/6567—Treatment time
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
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Abstract
The invention discloses a recycling method of honeycomb ceramic waste, which comprises the following steps: collecting scrap materials generated in the process of producing the silicon carbide honeycomb ceramics; crushing the leftover bits and pieces; adding deionized water, and kneading in a kneading device; adding a plasticizer; then, dispersing the pug by using an oil lubricant; the normal honeycomb ceramic pug is prepared by a normal honeycomb ceramic pug preparation process and is finally burnt to 900-1400 ℃. The invention provides a recycling method for unsintered silicon carbide honeycomb ceramic waste, and the method restores the plasticity of honeycomb ceramic pug by adjusting components for providing plasticity in the waste, so that the honeycomb ceramic pug can be restored to a smooth shaping state; and after the honeycomb ceramic product is prepared, the requirements of the particle collector of the national five non-roads are met.
Description
Technical Field
The invention relates to the technical field of honeycomb ceramic materials, in particular to a recycling method of honeycomb ceramic waste.
Background
Silicon carbide as a honeycomb ceramic material has low thermal expansion, high thermal shock resistance, high thermal conductivity and high temperature resistance, and the silicon carbide material becomes the first choice of the diesel particulate filter since the fifth and sixth discharge standards are implemented in China at present. In order to meet the emission requirements of the fifth and sixth countries, all engines using diesel as fuel need to be provided with a particle catcher, and the diesel particle catcher is called as DPF for short.
In the actual production of the silicon carbide honeycomb ceramic, scrap materials are inevitably generated due to the size requirement or modification of products, the scrap materials are not sintered and are completely dried by a drying line, but the minimum sintering temperature of the silicon carbide honeycomb ceramic is not reached, and the components influencing the sintering performance are not obviously changed; because the content of the silicon carbide material is extremely low in nature, basically 99.9 percent of the silicon carbide is artificially synthesized, and if the silicon carbide is directly discarded, the silicon carbide material is wasted, and the treatment mode is not good.
Therefore, how to provide a simple recycling method of honeycomb ceramic waste is a technical problem that needs to be solved by those skilled in the art.
Disclosure of Invention
In view of the above, the invention provides a recycling method for unsintered silicon carbide honeycomb ceramic waste, and the method recovers the plasticity of honeycomb ceramic pug by adjusting components providing plasticity in the waste, so that the honeycomb ceramic pug can be recovered to a smooth molding state; and after the honeycomb ceramic product is prepared, the requirements of the particle collector of the national five non-roads are met.
In order to achieve the purpose, the invention adopts the following technical scheme:
a recycling method of honeycomb ceramic waste comprises the following steps:
the method comprises the following steps: collecting scrap materials generated in the process of producing the silicon carbide honeycomb ceramics;
step two: crushing the leftover materials until the diameter is less than 10mm;
step three: adding deionized water accounting for 18-25% of the weight of the waste, and kneading in a kneading device for 20-240 min;
step four: adding a plasticizer accounting for 0.5-10% of the weight of the waste, wherein the step can be carried out after the step three is completed;
step five: adding an oil lubricant which accounts for 0.3 to 3 percent of the weight of the waste to disperse the pug;
step six: the normal honeycomb ceramic pug is prepared by a normal honeycomb ceramic pug preparation process, and is finally burnt to 900-1400 ℃, and the temperature is kept for 2-16 h.
The sintering scheme is only suitable for products with the sintering temperature of 900-1400 ℃ of the original silicon carbide honeycomb ceramic product, and is not suitable for products with the sintering temperature of more than 1400 ℃; but the principle applies.
Preferably, the crushing in the second step is to crush the leftover bits and pieces by a kneading device or a crusher.
Preferably, step three further comprises: adding silicon carbide micro powder accounting for 1-3 percent of the weight of the waste and deionized water accounting for 18-25 percent of the weight of the waste, and kneading for 60min in kneading equipment. The sufficient water content of the pug is ensured, the water content close to the original pug is kept, and the subsequent extrusion fluency is convenient.
Preferably, the plasticizer in step four comprises: 1000-20000 molecular weight cellulose, 700-6000 molecular weight PEG, 3-60 viscosity PVA, glycerol, polyethylene glycol in one or more. The step ensures the sufficient plasticity of the pug, so that the plasticity of the pug is close to the plasticity of the original pug, and the plasticity and the extrusion toughness of the pug are ensured.
Preferably, in step five, the oil lubricant comprises: one of triethylene glycol, oleic acid, alcohols, glycerol monooleate, glycerol and fatty acid. The step ensures the fluency of the pug in the extrusion process.
According to the technical scheme, compared with the prior art, the invention has the following beneficial effects:
the invention can effectively improve the utilization rate of the silicon carbide honeycomb ceramic pug, maximally utilize the raw materials, meet the requirements of the national fifth discharge standard on the premise of no environmental pollution of derivatives (products), and make a contribution to environmental protection.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
A recycling method of honeycomb ceramic waste comprises the following steps:
the method comprises the following steps: 120kg of leftover materials generated in the process of producing the silicon carbide honeycomb ceramic are collected;
step two: crushing the leftover materials to a diameter smaller than 10mm by a crusher;
step three: adding deionized water accounting for 20 percent of the weight of the waste, and kneading in a kneader for 60min;
step four: adding 3% glycerol by weight of the waste, wherein the step can be carried out after the step three is completed;
step five: dispersing the pug by adding a fatty acid preparation (126 pressing aid) accounting for 0.6 percent of the weight of the waste;
step six: the silicon carbide honeycomb ceramic is prepared by a normal honeycomb ceramic pug preparation process, finally is burnt to 1200 ℃, and is kept warm for 4 hours, so that a silicon carbide honeycomb ceramic product with high quality can be obtained.
Example 2
A recycling method of honeycomb ceramic waste comprises the following steps:
the method comprises the following steps: 120kg of leftover materials generated in the process of producing the silicon carbide honeycomb ceramics are collected;
step two: crushing the leftover materials to a diameter smaller than 10mm by a crusher;
step three: adding 1% silicon carbide micropowder (D50 =3.2 μm) and 20% deionized water by weight of the scrap, and kneading in a kneader for 60min;
step four: adding 3% glycerol by weight of the waste, wherein the step can be carried out after the step three is completed;
step five: dispersing the pug by adding a fatty acid preparation (126 compression aid) accounting for 0.6 percent of the weight of the waste;
step six: the silicon carbide honeycomb ceramic is prepared by a normal honeycomb ceramic pug preparation process, finally is burnt to 1200 ℃, and is kept warm for 4 hours, so that a silicon carbide honeycomb ceramic product with high quality can be obtained.
Effect testing
The silicon carbide honeycomb ceramic products obtained in examples 1 and 2 were subjected to the strength test, and the results are shown in table 1:
TABLE 1
Example 3
A recycling method of honeycomb ceramic waste comprises the following steps:
the method comprises the following steps: 120kg of leftover materials generated in the process of producing the silicon carbide honeycomb ceramic are collected;
step two: crushing the leftover materials to a diameter smaller than 10mm by a crusher;
step three: adding 3% by weight of silicon carbide micropowder (D50 =3.2 μm) and 18% by weight of deionized water to the waste, and kneading in a kneader for 60min;
step four: adding polyethylene glycol accounting for 10% of the weight of the waste, wherein the step can be carried out after the step three is completed;
step five: dispersing the pug by adding triethylene glycol accounting for 5 percent of the weight of the waste;
step six: the silicon carbide honeycomb ceramic is prepared by a normal honeycomb ceramic pug preparation process, finally is burnt to 1400 ℃, and is kept warm for 2 hours, so that a silicon carbide honeycomb ceramic product with high quality can be obtained.
Example 4
A recycling method of honeycomb ceramic waste comprises the following steps:
the method comprises the following steps: 120kg of leftover materials generated in the process of producing the silicon carbide honeycomb ceramics are collected;
step two: crushing the leftover materials to a diameter smaller than 10mm by a crusher;
step three: adding silicon carbide micropowder (D50 =3.2 μm) accounting for 3% of the weight of the waste and deionized water accounting for 25% of the weight of the waste, and kneading in a kneader for 60min;
step four: adding PEG (molecular weight of 5000) accounting for 0.5% of the weight of the waste, wherein the step can be carried out after the step three is completed;
step five: dispersing the pug by adding triethylene glycol accounting for 0.5 percent of the weight of the waste;
step six: the silicon carbide honeycomb ceramic is prepared by a normal honeycomb ceramic pug preparation process, finally is burnt to 1000 ℃ and is kept warm for 12 hours, and a silicon carbide honeycomb ceramic product with high quality can be obtained.
Example 5
A recycling method of honeycomb ceramic waste comprises the following steps:
the method comprises the following steps: 120kg of leftover materials generated in the process of producing the silicon carbide honeycomb ceramics are collected;
step two: crushing the leftover materials to a diameter smaller than 10mm by a crusher;
step three: adding deionized water accounting for 18 percent of the weight of the waste, and kneading in a kneader for 20min;
step four: adding PVA (viscosity of 25) accounting for 4% of the weight of the waste, wherein the step can be carried out after the step three is completed;
step five: dispersing the pug by adding a fatty acid preparation (126 compression aid) accounting for 2.5 percent of the weight of the waste;
step six: the silicon carbide honeycomb ceramic is prepared by a normal honeycomb ceramic pug preparation process, finally is burnt to 1200 ℃, and is kept warm for 16 hours, so that a silicon carbide honeycomb ceramic product with high quality can be obtained.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (5)
1. A method for recycling honeycomb ceramic waste is characterized by comprising the following steps:
the method comprises the following steps: collecting scrap materials generated in the process of producing the silicon carbide honeycomb ceramics;
step two: crushing the leftover materials until the diameter is less than 10mm;
step three: adding deionized water accounting for 18-25% of the weight of the waste, and kneading for 20-120 min in kneading equipment;
step four: adding a plasticizer accounting for 0.5-10% of the weight of the waste, wherein the step can be carried out after the step three is completed;
step five: adding an oil lubricant which accounts for 0.3 to 3 percent of the weight of the waste to disperse the pug;
step six: the honeycomb ceramic is prepared by a normal honeycomb ceramic pug preparation process, and is finally burnt to 900-1400 ℃, and the temperature is kept for 2-16 h.
2. The method for recycling honeycomb ceramic waste according to claim 1, wherein the crushing in the second step is crushing of the corner waste by a kneading device or a crusher.
3. The recycling method of the honeycomb ceramic waste material according to claim 1, wherein the third step further comprises: adding silicon carbide micro powder accounting for 1-3 percent of the weight of the waste and deionized water accounting for 18-25 percent of the weight of the waste, and kneading for 20-60 min in kneading equipment.
4. The recycling method of the honeycomb ceramic waste material according to claim 1 or 3, wherein the plasticizer in the fourth step comprises: 1000-20000 molecular weight cellulose, 700-6000 molecular weight PEG, 3-60 viscosity PVA, glycerol, polyethylene glycol or a mixture thereof.
5. The method for recycling honeycomb ceramic waste according to claim 1 or 3, wherein the oil-based lubricant in step five comprises: one or more of triethylene glycol, oleic acid, alcohols, glycerol monooleate, glycerol and fatty acid are mixed for use.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210962510.1A CN115286417A (en) | 2022-08-11 | 2022-08-11 | Recycling method of honeycomb ceramic waste |
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Cited By (1)
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| CN115893983A (en) * | 2023-01-10 | 2023-04-04 | 山东奥福环保科技股份有限公司 | Method for preparing honeycomb ceramic carrier by using honeycomb ceramic carrier green compact and carrier |
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