CN114573371A - Deep impregnation method of isostatic pressing graphite - Google Patents
Deep impregnation method of isostatic pressing graphite Download PDFInfo
- Publication number
- CN114573371A CN114573371A CN202210403432.1A CN202210403432A CN114573371A CN 114573371 A CN114573371 A CN 114573371A CN 202210403432 A CN202210403432 A CN 202210403432A CN 114573371 A CN114573371 A CN 114573371A
- Authority
- CN
- China
- Prior art keywords
- impregnation
- pressure
- asphalt
- tank
- cooling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000005470 impregnation Methods 0.000 title claims abstract description 117
- 238000000034 method Methods 0.000 title claims abstract description 51
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 43
- 239000010439 graphite Substances 0.000 title claims abstract description 43
- 229910002804 graphite Inorganic materials 0.000 title claims abstract description 43
- 238000000462 isostatic pressing Methods 0.000 title claims abstract description 28
- 239000010426 asphalt Substances 0.000 claims abstract description 82
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 72
- 238000001816 cooling Methods 0.000 claims abstract description 43
- 239000007788 liquid Substances 0.000 claims abstract description 38
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 34
- 238000010438 heat treatment Methods 0.000 claims abstract description 19
- 238000007599 discharging Methods 0.000 claims abstract description 14
- 238000007598 dipping method Methods 0.000 claims abstract description 11
- 238000002791 soaking Methods 0.000 claims abstract description 11
- 229910001873 dinitrogen Inorganic materials 0.000 claims abstract description 4
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 12
- 239000000654 additive Substances 0.000 claims description 10
- 230000000996 additive effect Effects 0.000 claims description 10
- 238000005086 pumping Methods 0.000 claims description 9
- WRIDQFICGBMAFQ-UHFFFAOYSA-N (E)-8-Octadecenoic acid Natural products CCCCCCCCCC=CCCCCCCC(O)=O WRIDQFICGBMAFQ-UHFFFAOYSA-N 0.000 claims description 4
- LQJBNNIYVWPHFW-UHFFFAOYSA-N 20:1omega9c fatty acid Natural products CCCCCCCCCCC=CCCCCCCCC(O)=O LQJBNNIYVWPHFW-UHFFFAOYSA-N 0.000 claims description 4
- QSBYPNXLFMSGKH-UHFFFAOYSA-N 9-Heptadecensaeure Natural products CCCCCCCC=CCCCCCCCC(O)=O QSBYPNXLFMSGKH-UHFFFAOYSA-N 0.000 claims description 4
- ZQPPMHVWECSIRJ-UHFFFAOYSA-N Oleic acid Natural products CCCCCCCCC=CCCCCCCCC(O)=O ZQPPMHVWECSIRJ-UHFFFAOYSA-N 0.000 claims description 4
- 239000005642 Oleic acid Substances 0.000 claims description 4
- QXJSBBXBKPUZAA-UHFFFAOYSA-N isooleic acid Natural products CCCCCCCC=CCCCCCCCCC(O)=O QXJSBBXBKPUZAA-UHFFFAOYSA-N 0.000 claims description 4
- 239000003350 kerosene Substances 0.000 claims description 4
- ZQPPMHVWECSIRJ-KTKRTIGZSA-N oleic acid Chemical compound CCCCCCCC\C=C/CCCCCCCC(O)=O ZQPPMHVWECSIRJ-KTKRTIGZSA-N 0.000 claims description 4
- 239000003245 coal Substances 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- 230000004584 weight gain Effects 0.000 abstract description 7
- 235000019786 weight gain Nutrition 0.000 abstract description 7
- 230000000694 effects Effects 0.000 abstract description 6
- 238000005265 energy consumption Methods 0.000 abstract description 5
- 239000007770 graphite material Substances 0.000 abstract description 3
- 239000011148 porous material Substances 0.000 description 19
- 239000000463 material Substances 0.000 description 4
- 239000000571 coke Substances 0.000 description 3
- 239000002826 coolant Substances 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 239000011295 pitch Substances 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- 238000009736 wetting Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000011300 coal pitch Substances 0.000 description 1
- 238000004939 coking Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- 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
- C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
- C04B41/80—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only ceramics
- C04B41/81—Coating or impregnation
- C04B41/82—Coating or impregnation with organic materials
- C04B41/83—Macromolecular compounds
-
- 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
- C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
- C04B41/009—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone characterised by the material treated
-
- 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
- C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
- C04B41/45—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements
- C04B41/46—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements with organic materials
- C04B41/47—Oils, fats or waxes natural resins
- C04B41/478—Bitumen, asphalt, e.g. paraffin
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
- Y02P20/129—Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Civil Engineering (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Carbon And Carbon Compounds (AREA)
Abstract
The invention discloses a deep impregnation method of isostatic pressing graphite, relates to the technical field of graphite materials, and aims to solve the problems that the impregnation depth of the isostatic pressing graphite is not enough, the impregnation uniformity is poor, and the existing method is complex and complicated, has high energy consumption and is difficult to apply in actual production; placing an isostatic pressing graphite roasted product to be impregnated into an impregnation tank for preheating; vacuumizing the impregnation tank for the first time, filling nitrogen for pressurization, and vacuumizing for the second time; injecting asphalt liquid into the impregnation tank, soaking the roasted product, and then respectively injecting nitrogen gas for primary pressurization and secondary pressurization for impregnation; closing heating, discharging asphalt liquid, simultaneously introducing nitrogen, pressurizing to a pressure higher than the impregnation pressure, cooling the impregnated product, cooling to below the asphalt softening point, releasing the pressure, and continuously cooling; the dipping method of the invention can ensure that the dipped product achieves the deep and uniform dipping effect, the product has low porosity and high weight gain rate, and is suitable for isostatic pressing graphite with various specifications and structures.
Description
Technical Field
The invention relates to the technical field of graphite materials, in particular to a deep impregnation method of isostatic pressing graphite.
Background
Impregnation is a very important step in the graphite industry, determines the properties of the product and is generally carried out after calcination. After the green body is roasted, due to volatilization of light components, the original volume gradually forms a pore channel, so that the interior of the product is porous, the density is reduced, and the performance of a finished product is influenced. The purpose of impregnation is to fill the pores and the open pores originally existing in the aggregate coke particles with an impregnating agent such as molten pitch, and to reduce the porosity and improve the properties such as material density, strength, electrical resistance, expansion coefficient and the like by secondary baking.
The existing impregnation process of graphite products mainly comprises the following steps: preheating, vacuumizing, injecting impregnating solution, pressurizing, maintaining pressure, decompressing, discharging the impregnating solution and cooling. For common or coarse-grained, small-gauge graphite, the process can generally meet practical requirements. With the gradual development of graphite materials to high-end fields such as large specification, fine structure, high density and the like, the existing impregnation process cannot adapt to the requirements.
For high-end graphite, the depth and uniformity of impregnation have a crucial influence on the product performance. The conventional impregnation often has the problems of insufficient impregnation depth, deviation of impregnation uniformity and the like, and the impregnant in the impregnated product is easy to flow out from the inside in the impregnation cooling process, so that the impregnation effect is seriously reduced. In addition, the impregnant is wasted, and the product appearance is influenced.
The invention has the publication number of CN104446646B, and is named as an impregnation method for preparing isostatic pressing graphite products, and discloses an isostatic pressing graphite impregnation method which comprises the steps of heating and preheating an isostatic pressing graphite product, then injecting liquid asphalt and pressurizing for impregnation, cooling to 50-60 ℃ under pressurization without discharging the asphalt after the impregnation is finished, then heating and heating to above the asphalt softening point, ensuring that the surface temperature of the product is just at the asphalt softening point, finally releasing pressure to discharge the asphalt, and cooling, wherein the method can prevent impregnant from flowing out of the graphite to a certain extent, but needs complicated steps of cooling, heating, cooling and the like, in addition, because the impregnant is always in an impregnation system, the cooling and cooling rate is slow, the heating temperature is difficult to control, the product quality is uneven, the energy consumption is further improved, the production period is greatly prolonged, the efficiency is low, the production cost cannot be controlled at a reasonable level, and tests show that the method is difficult to apply in actual production. Therefore, a method of deep impregnation of isostatic graphite is needed to solve these problems.
Disclosure of Invention
The invention aims to provide a deep impregnation method of isostatic pressing graphite, which aims to solve the problems that the impregnation depth of the isostatic pressing graphite is not enough, the impregnation uniformity is poor, the existing method is complicated and complicated, the energy consumption is high, and the application in practical production is difficult.
In order to achieve the purpose, the invention provides the following technical scheme: a deep impregnation method of isostatic pressing graphite comprises the following steps:
step one, preheating: placing an isostatic pressing graphite roasted product to be impregnated into an impregnation tank, and preheating;
step two, channel dredging: vacuumizing the impregnation tank for the first time, then filling nitrogen for pressurization, and vacuumizing for the second time, so that the inner pore of a roasted product is dredged, and the aperture ratio of the roasted product is improved;
step three, dipping: injecting asphalt liquid into the impregnation tank, soaking the roasted product, and then respectively injecting nitrogen gas for primary pressurization and secondary pressurization for impregnation;
step four, cooling: and (3) closing the heating, discharging the asphalt liquid, simultaneously filling nitrogen, cooling the dipped product under the condition of pressurizing to a pressure higher than the dipping pressure, releasing the pressure after cooling to a temperature below the asphalt softening point, and continuing cooling.
Preferably, in the first step, the preheating temperature is 270-330 ℃, and the preheating temperature rise rate is 20-60 ℃/h; further preferably, the preheating temperature is 240-300 ℃, so that the product to be dipped can expand to a proper degree, and internal air holes can be opened easily; furthermore, before the roasted product is preheated, the surface of the roasted product can be cleaned, and the surface of the roasted product can be polished to remove residual coke and dirt, so that air holes of the roasted product are exposed, and the roasted product is favorable for impregnation.
Preferably, in the second step, the pressure in the tank is 300-1000 Pa after one-time vacuum pumping, the pressure is maintained for 1-4 h, the opening pretreatment is carried out for one-time vacuum pumping, the moisture and particle impurities in the roasted product can be discharged, the opening quality and the uniformity can be ensured, and the impregnation depth and the uniformity of the product are greatly influenced.
Preferably, in the second step, nitrogen is filled into the roasting product to pressurize the roasting product until the pressure in the roasting product is 0.4-1.2 MPa, and the pressure is maintained for 2-6 hours, so that the opening of the inner pore channel of the roasted product is facilitated.
Preferably, in the second step, secondary vacuum pumping is performed until the pressure in the tank is 50-200 Pa, and the pressure is maintained for 2-6 hours, so as to further completely open the holes of the roasted product, and meanwhile, the formed negative pressure is favorable for entering of asphalt liquid in the subsequent impregnation step.
Preferably, in the third step, an additive is added into the asphalt liquid, the additive is one of kerosene, toluene or oleic acid, the mass percentage content of the additive is 1-3%, the temperature of the injected asphalt liquid is 220-260 ℃, and the soaking time is 1-4 hours, so that the asphalt liquid enters a roasting product large pore channel.
Preferably, in the third step, the pressure is increased to 1.2-2.4 MPa for 1-4 h; secondarily pressurizing to 3.0-4.0 MPa, and maintaining the pressure for 2-10 h; the asphalt enters the pore channel of the roasted product in a layered mode through two times of pressurization, the asphalt firstly enters the large pore channel and wets the small and micro pore channels simultaneously when being soaked, the pressure of the primary pressurization is not very large, asphalt liquid is quickly saturated in the large pore channel and gradually wets the small and micro pore channels, the pressure of the secondary pressurization is relatively large, the large pore channel is quickly saturated along with the increase of the pressure, the small and micro pore channels which are originally wetted by the asphalt liquid are gradually filled with the asphalt until no asphalt enters any more, and the balance state is achieved.
Preferably, in the fourth step, nitrogen is filled while discharging the asphalt liquid, the pressure is maintained at 4.0-5.0 MPa, the pressure is maintained so that the pressure in the tank is kept unchanged in the asphalt discharging process, the pressure is maintained until the temperature in the tank is reduced to be below the asphalt softening point, the dipped product is cooled under pressurization, the pressure of the dipped product is higher than the pressure of twice pressurization for dipping, the asphalt liquid which enters the dipped product is effectively prevented from being discharged, the asphalt in the dipped product is lack of fluidity after being cooled to the softening point and cannot be discharged, and the pressure is released at this moment and the dipped product is continuously cooled.
Preferably, the asphalt used in the asphalt liquid is medium-temperature coal asphalt with a softening point of 75-95 ℃, and at the moment, the asphalt is cooled to 65-75 ℃ in the fourth step and then the pressure is released.
Compared with the prior art, the invention has the beneficial effects that:
1. the deep impregnation method of isostatic pressing graphite adopts the steps of inflating, pressurizing and cooling an impregnation product to a temperature below the asphalt softening point; because the asphalt maintains dynamic balance in the impregnant and the impregnation tank in the pressurizing impregnation process, after the impregnation is finished, when the asphalt is discharged once, a hydraulic part is reduced, the balance can be broken immediately, even if the pressure in the tank is continuously maintained at the impregnation pressure, a small amount of asphalt can also flow out from the impregnant, in addition, the asphalt flows out from the interior due to further aggravation of expansion caused by heat and contraction caused by cold in the cooling process, and the quality difference of products of different batches often exists; the deep impregnation method of isostatic pressing graphite adopts pressurized cooling to prevent dynamic balance from being broken when discharging asphalt liquid, thereby effectively preventing asphalt in an impregnation product from overflowing to the outer surface, under the condition, when the asphalt is cooled to be below an asphalt softening point, the asphalt loses fluidity without the possibility of overflowing, at the moment, pressure can be released for continuous cooling, the method can ensure that the asphalt which is impregnated into a pore channel is not discharged completely, energy consumption in the production process is not wasted, and the impregnation depth, uniformity and consistency can reach the best level.
2. The deep dipping method of isostatic pressing graphite can also assist in accelerating the cooling rate by the nitrogen gas filled in the pressurizing and cooling process.
3. The deep impregnation method of isostatic pressing graphite utilizes the distribution operations of primary vacuumizing, inflation pressurizing and secondary vacuumizing, and utilizes the vacuum degree and pressurized nitrogen to repeatedly impact the inner pore channels of the roasted product, so that the open pore channels are dredged, partial closed pore channels are dredged, obstacles are cleared for the subsequent entering of asphalt, the impregnation effect is improved, and the integral improvement of the product quality is facilitated.
4. The deep impregnation method of isostatic pressing graphite adds a small amount of additive into the impregnant asphalt, thus improving the fluidity of asphalt liquid and having good impregnation and wetting effects on the roasted product.
5. The deep impregnation method of isostatic pressing graphite comprises the steps of soaking a roasted product by using asphalt liquid, pressurizing for the first time and pressurizing for the second time, so that asphalt enters a pore passage of the roasted product in a layered mode, the impregnation is easy to carry out, the wetting effect of impregnant asphalt plays a role in guiding the subsequent pressurized impregnation, and the impregnation depth is guaranteed.
6. The weight gain of the dipped product prepared by the method of the invention reaches more than 15 percent, and the density of the product can reach 1.8g/m3As described above, the impregnation depth and uniformity were good.
Drawings
FIG. 1 is a schematic process flow diagram of the present invention.
Detailed Description
As shown in fig. 1, a deep impregnation method of isostatic pressing graphite comprises the following steps:
preheating: placing an isostatic pressing graphite roasting product to be soaked in a soaking tank, and preheating, wherein the preheating temperature can be 270-330 ℃, and the preheating heating rate is 20-60 ℃/h; preferably, the preheating temperature is 240-300 ℃; furthermore, before the roasted product is preheated, the surface of the roasted product can be cleaned and polished to remove residual coke and dirt on the surface;
and (4) dredging the pore channel: carrying out primary vacuum pumping on the impregnation tank, preferably carrying out primary vacuum pumping until the pressure in the impregnation tank is 300-1000 Pa, maintaining the pressure for 1-4 h, then filling nitrogen for pressurization, preferably pressurizing until the pressure in the impregnation tank is 0.4-1.2 MPa, maintaining the pressure for 2-6 h, and then carrying out secondary vacuum pumping, preferably carrying out secondary vacuum pumping until the pressure in the impregnation tank is 50-200 Pa, and maintaining the pressure for 2-6 h;
dipping: injecting asphalt liquid into an impregnation tank, soaking the roasted product, and then respectively injecting nitrogen for primary pressurization and secondary pressurization for impregnation, wherein the primary pressurization is preferably carried out to 1.2-2.4 MPa, the pressure is maintained for 1-4 h, the secondary pressurization is preferably carried out to 3.0-4.0 MPa, and the pressure is maintained for 2-10 h; in a preferred embodiment, an additive is added into the asphalt liquid, the additive is one of kerosene, toluene or oleic acid, the mass percentage content of the additive is 1-3%, the temperature of the injected asphalt liquid is 220-260 ℃, and the soaking time is 1-4 hours; keeping the heating state from preheating to soaking until cooling; the impregnant has higher coking value and good fluidity, the medium-temperature coal pitch has relevant characteristics, the impregnation is carried out at higher temperature, but the performance of the impregnant is not favorably exerted at the overhigh temperature, the impregnation effect is better at 220-260 ℃, and the fluidity of the impregnant can be improved by adding a small amount of kerosene, toluene and oleic acid into the pitch liquid, so that the impregnation is facilitated.
And (3) cooling: and closing the heating, filling nitrogen while discharging the asphalt liquid, and cooling the dipped product under the condition of pressurizing to a pressure higher than the dipping pressure, wherein under the condition that the secondary pressurizing adopts 3.0-4.0 MPa, the cooling pressurizing is preferably maintained at 4.0-5.0 MPa, more preferably, 1MPa is added on the basis of the secondary pressurizing pressure, the pressure is released after cooling to the temperature below the softening point of the asphalt, and the cooling is continued, wherein the asphalt in the asphalt liquid preferably adopts medium-temperature coal asphalt, the softening point of the asphalt is 75-95 ℃, and the pressure is released after cooling to 65-75 ℃ during cooling.
The cooling process can adopt various modes, such as coolant cooling, natural cooling, pressurized cooling stage natural cooling and pressure-releasing coolant cooling, and the like, and can be determined according to the process needs, economic benefits and the like.
Example 1
Placing the isostatic pressing graphite roasted product in an impregnation tank, heating up and preheating to 270 ℃, wherein the heating-up rate is 30 ℃/h; vacuumizing the impregnation tank for the first time to reduce the pressure to 500Pa, maintaining the pressure for 2h, then injecting nitrogen into the impregnation tank to increase the pressure to 0.6MPa, maintaining the pressure for 3h, vacuumizing for the second time to reduce the pressure to 100MPa, and maintaining the pressure for 3 h; injecting liquid asphalt into the impregnation tank, keeping the asphalt temperature at 250 ℃, after soaking the asphalt liquid for 2 hours, filling nitrogen into the impregnation tank until the pressure reaches 1.8MPa, keeping the pressure for 2 hours, then continuously filling nitrogen until the pressure in the tank reaches 3.5MPa, keeping the pressure for 6 hours, and keeping the temperature in the tank at 250 ℃ in the impregnation process; and after the impregnation is finished, closing the heating, continuously filling nitrogen, discharging the asphalt, keeping the pressure in the tank at 4.5MPa until the temperature is reduced to 70 ℃, then stopping filling the nitrogen, releasing the pressure in the tank, and naturally cooling the impregnated product. The weight gain rate of the dipped product obtained by the method reaches 15.6 percent, and the volume density reaches 1.88g/cm3The depth and uniformity of impregnation was close to 100%.
Example 2
Placing the isostatic pressing graphite roasted product in an impregnation tank, heating up and preheating to 240 ℃, wherein the heating-up rate is 20 ℃/h;vacuumizing the impregnation tank for the first time to reduce the pressure to 300Pa, maintaining the pressure for 1h, then injecting nitrogen into the impregnation tank to increase the pressure to 0.4MPa, maintaining the pressure for 2h, vacuumizing for the second time to reduce the pressure to 200MPa, and maintaining the pressure for 2 h; injecting liquid asphalt into the impregnation tank, wherein the asphalt temperature is 220 ℃, after the asphalt liquid is soaked for 1h, filling nitrogen into the impregnation tank until the pressure reaches 1.2MPa, maintaining the pressure for 1h, then continuously filling nitrogen until the pressure in the impregnation tank reaches 3.0MPa, maintaining the pressure for 2h, and maintaining the temperature in the impregnation tank at 220 ℃ in the impregnation process; and after the impregnation is finished, closing the heating, continuously filling nitrogen, discharging the asphalt, keeping the pressure in the tank at 4.0MPa until the temperature is reduced to 65 ℃, then stopping filling the nitrogen, releasing the pressure in the tank, and naturally cooling the impregnated product. The weight gain of the dipped material obtained by the method reaches 15.2 percent, and the volume density reaches 1.84g/cm3The depth and uniformity of impregnation was close to 100%.
Example 3
Placing the isostatic pressing graphite roasted product in an impregnation tank, heating up and preheating to 300 ℃, wherein the heating-up rate is 60 ℃/h; vacuumizing the impregnation tank for the first time to reduce the pressure to 300Pa, maintaining the pressure for 4h, then injecting nitrogen into the impregnation tank to increase the pressure to 1.2MPa, maintaining the pressure for 6h, vacuumizing for the second time to reduce the pressure to 50MPa, and maintaining the pressure for 6 h; injecting liquid asphalt into the impregnation tank, keeping the asphalt temperature at 260 ℃, after the asphalt liquid is soaked for 4 hours, filling nitrogen into the impregnation tank until the pressure reaches 2.4MPa, maintaining the pressure for 4 hours, then continuously filling nitrogen until the pressure in the impregnation tank reaches 4.0MPa, maintaining the pressure for 10 hours, and maintaining the temperature in the impregnation tank at 260 ℃; and after the impregnation is finished, closing the heating, continuously filling nitrogen, discharging the asphalt, keeping the pressure in the tank at 5.0MPa until the temperature is reduced to 75 ℃, then stopping filling the nitrogen, releasing the pressure in the tank, and naturally cooling the impregnated product. The weight gain rate of the dipped material obtained by the method reaches 16.1 percent, and the volume density reaches 1.90g/cm3The depth and uniformity of impregnation was close to 100%.
Example 4
Placing the isostatic pressing graphite roasted product in an impregnation tank, heating up and preheating to 250 ℃, wherein the heating-up rate is 40 ℃/h; the impregnation tank is vacuumized once to reduce the pressure to 600PaMaintaining the pressure for 2h, then injecting nitrogen into the impregnation tank, increasing the pressure to 1.0MPa, maintaining the pressure for 5h, then secondarily vacuumizing, reducing the pressure to 150MPa, and maintaining the pressure for 3 h; injecting liquid asphalt into the impregnation tank, wherein the asphalt temperature is 230 ℃, after the asphalt liquid is soaked for 1h, filling nitrogen into the impregnation tank until the pressure reaches 2.0MPa, maintaining the pressure for 4h, then continuously filling nitrogen until the pressure in the impregnation tank reaches 3.6MPa, maintaining the pressure for 8h, and maintaining the temperature in the impregnation tank at 230 ℃ in the impregnation process; and after the impregnation is finished, closing the heating, continuously filling nitrogen, discharging the asphalt, keeping the pressure in the tank at 4.6MPa until the temperature is reduced to 70 ℃, then stopping filling the nitrogen, releasing the pressure in the tank, and naturally cooling the impregnated product. The weight gain of the dipped material obtained by the method reaches 15.7 percent, and the volume density reaches 1.86g/cm3The depth and uniformity of impregnation was close to 100%.
The technological parameters adopted in the four embodiments are different, but the whole thinking is the same, the finally obtained products of different batches have similar performances, the weight gain rate is 15.2-16.1%, the difference is less than 1%, and the volume density is 1.84-1.90g/cm3With a difference of only 0.06g/cm3The product consistency is good, and because the dipping process is simple, almost no extra energy consumption exists, and the method is suitable for production and application.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are also included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope defined by the claims.
The present invention is not described in detail, but is known to those skilled in the art.
Claims (10)
1. The deep impregnation method of the isostatic pressing graphite is characterized by comprising the following steps:
step one, preheating: placing an isostatic pressing graphite roasted product to be impregnated into an impregnation tank, and preheating;
step two, channel dredging: vacuumizing the impregnation tank for the first time, filling nitrogen for pressurization, and vacuumizing for the second time;
step three, dipping: injecting asphalt liquid into the impregnation tank, soaking the roasted product, and then respectively injecting nitrogen gas for primary pressurization and secondary pressurization for impregnation;
step four, cooling: and (3) closing the heating, discharging the asphalt liquid, simultaneously filling nitrogen, cooling the dipped product under the condition of pressurizing to a pressure higher than the dipping pressure, releasing the pressure after cooling to a temperature below the asphalt softening point, and continuing cooling.
2. The method for deep impregnation of isostatic graphite according to claim 1, wherein: in the first step, the preheating temperature is 270-330 ℃, and the preheating temperature rise rate is 20-60 ℃/h.
3. The method for deep impregnation of isostatic graphite according to claim 1, wherein: in the second step, primary vacuum pumping is carried out until the pressure in the tank is 300-1000 Pa, and the pressure is maintained for 1-4 h.
4. A method for deep impregnation of isostatically pressed graphite according to claim 3, wherein: and in the second step, nitrogen is filled into the tank to pressurize the tank until the pressure in the tank is 0.4-1.2 MPa, and the pressure is maintained for 2-6 hours.
5. The method for deep impregnation of isostatic graphite according to claim 4, wherein: and in the second step, secondary vacuum pumping is carried out until the pressure in the tank is 50-200 Pa, and the pressure is maintained for 2-6 h.
6. The method for deep impregnation of isostatic graphite according to claim 1, wherein: in the third step, an additive is added into the asphalt liquid, the component of the additive is one of kerosene, toluene or oleic acid, the mass percentage content of the additive is 1-3%, the temperature of the injected asphalt liquid is 220-260 ℃, and the soaking time is 1-4 hours.
7. The method for the deep impregnation of isostatic graphite as claimed in claim 1, wherein: and in the third step, once pressurizing to 1.2-2.4 MPa, and maintaining the pressure for 1-4 h.
8. The method for deep impregnation of isostatic graphite according to claim 7, wherein: and in the third step, pressurizing for the second time to 3.0-4.0 MPa, and maintaining the pressure for 2-10 hours.
9. The method for deep impregnation of isostatic graphite according to claim 8, wherein: and in the fourth step, nitrogen is filled while discharging the asphalt liquid, and the pressure is maintained to be 4.0-5.0 MPa.
10. The method for the deep impregnation of isostatic graphite as claimed in claim 1, wherein: the asphalt used in the asphalt liquid is medium-temperature coal asphalt with the softening point of 75-95 ℃, and the pressure is released after the asphalt liquid is cooled to 65-75 ℃ in the fourth step.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210403432.1A CN114573371A (en) | 2022-04-18 | 2022-04-18 | Deep impregnation method of isostatic pressing graphite |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210403432.1A CN114573371A (en) | 2022-04-18 | 2022-04-18 | Deep impregnation method of isostatic pressing graphite |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114573371A true CN114573371A (en) | 2022-06-03 |
Family
ID=81783873
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210403432.1A Pending CN114573371A (en) | 2022-04-18 | 2022-04-18 | Deep impregnation method of isostatic pressing graphite |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114573371A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114940628A (en) * | 2022-06-22 | 2022-08-26 | 湖南晶碳新材料有限公司 | A calcination article preprocessing device for flooding |
| CN115215656A (en) * | 2022-08-11 | 2022-10-21 | 中钢集团南京新材料研究院有限公司 | Preparation method of binder-free high-density graphite material and prepared graphite material |
| CN115259898A (en) * | 2022-08-09 | 2022-11-01 | 中钢集团南京新材料研究院有限公司 | Dipping method of isostatic pressing graphite product and product thereof |
| CN115572168A (en) * | 2022-09-19 | 2023-01-06 | 中钢集团南京新材料研究院有限公司 | Method for increasing impregnation weight gain rate of graphite roasted product |
| CN116443870A (en) * | 2023-04-23 | 2023-07-18 | 河南碳路者新材料科技有限公司 | Isostatic pressure graphite impregnating device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104446646A (en) * | 2014-12-04 | 2015-03-25 | 大同新成新材料股份有限公司 | Impregnating method of preparing isostatic pressing graphite product |
| CN108727063A (en) * | 2018-06-01 | 2018-11-02 | 中钢集团新型材料（浙江）有限公司 | A kind of dipping method for the big specification isostatic pressing formed graphite of fine texture high density |
| CN108752046A (en) * | 2018-06-01 | 2018-11-06 | 大同新成新材料股份有限公司 | A kind of dipping method preparing isostatic pressing formed graphite product |
| CN108816675A (en) * | 2018-06-01 | 2018-11-16 | 中钢集团新型材料（浙江）有限公司 | One kind being used for impregnating pitch reverse osmosis process |
| CN114057487A (en) * | 2021-12-14 | 2022-02-18 | 中钢集团南京新材料研究院有限公司 | Isostatic pressing graphite preparation device and preparation method |
| CN216150243U (en) * | 2021-08-24 | 2022-04-01 | 吉林炭素有限公司 | Carbon electrode impregnation pressure device |
-
2022
- 2022-04-18 CN CN202210403432.1A patent/CN114573371A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104446646A (en) * | 2014-12-04 | 2015-03-25 | 大同新成新材料股份有限公司 | Impregnating method of preparing isostatic pressing graphite product |
| CN108727063A (en) * | 2018-06-01 | 2018-11-02 | 中钢集团新型材料（浙江）有限公司 | A kind of dipping method for the big specification isostatic pressing formed graphite of fine texture high density |
| CN108752046A (en) * | 2018-06-01 | 2018-11-06 | 大同新成新材料股份有限公司 | A kind of dipping method preparing isostatic pressing formed graphite product |
| CN108816675A (en) * | 2018-06-01 | 2018-11-16 | 中钢集团新型材料（浙江）有限公司 | One kind being used for impregnating pitch reverse osmosis process |
| CN216150243U (en) * | 2021-08-24 | 2022-04-01 | 吉林炭素有限公司 | Carbon electrode impregnation pressure device |
| CN114057487A (en) * | 2021-12-14 | 2022-02-18 | 中钢集团南京新材料研究院有限公司 | Isostatic pressing graphite preparation device and preparation method |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114940628A (en) * | 2022-06-22 | 2022-08-26 | 湖南晶碳新材料有限公司 | A calcination article preprocessing device for flooding |
| CN115259898A (en) * | 2022-08-09 | 2022-11-01 | 中钢集团南京新材料研究院有限公司 | Dipping method of isostatic pressing graphite product and product thereof |
| CN115215656A (en) * | 2022-08-11 | 2022-10-21 | 中钢集团南京新材料研究院有限公司 | Preparation method of binder-free high-density graphite material and prepared graphite material |
| CN115572168A (en) * | 2022-09-19 | 2023-01-06 | 中钢集团南京新材料研究院有限公司 | Method for increasing impregnation weight gain rate of graphite roasted product |
| CN115572168B (en) * | 2022-09-19 | 2023-09-22 | 中钢集团南京新材料研究院有限公司 | Method for improving impregnation weight gain rate of graphite roasting product |
| CN116443870A (en) * | 2023-04-23 | 2023-07-18 | 河南碳路者新材料科技有限公司 | Isostatic pressure graphite impregnating device |
| CN116443870B (en) * | 2023-04-23 | 2024-05-14 | 河南碳路者新材料科技有限公司 | Isostatic pressure graphite impregnating device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114573371A (en) | Deep impregnation method of isostatic pressing graphite | |
| EP1425147B1 (en) | Process for making porous graphite and articles produced therefrom | |
| DE3921980C2 (en) | ||
| CN105499574B (en) | A method of preparing hole uniformly complicated-shape porous tungsten product | |
| CN109261967B (en) | Electron beam partition scanning forming method for porous tungsten material | |
| CN108727063B (en) | Impregnation method for fine-structure high-density large-specification isostatic pressing graphite | |
| CN109251052A (en) | A kind of C/C composite material and preparation method | |
| CN100448328C (en) | Production method of ultrohigh power graphite electrode | |
| KR102641901B1 (en) | Carbon-silicon carbide target material and its manufacturing method and use | |
| CN109850870A (en) | A kind of high-strength carbon aeroge and its preparation method and application | |
| CN110642634A (en) | C/SiC-ZrB2Composite material and preparation method thereof | |
| CN108484173A (en) | SiCf/ SiC ceramic matrix composite material and preparation method thereof | |
| CN106363174B (en) | A kind of preparation method of the thin-wall special-shaped part of foamed aluminium | |
| CN111725478A (en) | Novel impregnation process for carbon strip production | |
| US2972552A (en) | All carbon impervious graphite and carbon articles | |
| CN110980686B (en) | Impregnation method of porous carbon material | |
| CN104627981A (en) | Carbon product impregnation technology | |
| CN114634361A (en) | Preparation method of isotropic isostatic pressing graphite with fine structure | |
| CN110066185B (en) | C/C-SiC-Al composite material and preparation method thereof | |
| CN117964399A (en) | Impregnation method of isostatic pressing graphite product | |
| CN113563088A (en) | Porous silicon nitride ceramic component and method for producing same | |
| JPH03295879A (en) | Method for impregnating metal into carbon material | |
| CN115259898B (en) | Impregnation method of isostatic pressing graphite product and product thereof | |
| CN111943187A (en) | Ultrahigh-power graphite electrode and preparation method thereof | |
| CN114932223B (en) | Co-sintering preparation method of metal matrix composite |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20220603 |