CN111943187A - Ultrahigh-power graphite electrode and preparation method thereof - Google Patents
Ultrahigh-power graphite electrode and preparation method thereof Download PDFInfo
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- CN111943187A CN111943187A CN202010848208.4A CN202010848208A CN111943187A CN 111943187 A CN111943187 A CN 111943187A CN 202010848208 A CN202010848208 A CN 202010848208A CN 111943187 A CN111943187 A CN 111943187A
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Abstract
The invention provides an ultrahigh power graphite electrode and a preparation method thereof, wherein the preparation method of the ultrahigh power graphite electrode comprises the following steps: s1, blending, crushing and screening; s2, kneading and molding to obtain a blank; s3, roasting and dipping; s31, roasting and dipping for the first time; after the green body is roasted, the temperature is reduced to 240-260 ℃, the green body is placed into an impregnation container, impregnation liquid A is injected after vacuum pumping, the pressure is increased by 2-3MPa, and the pressure is maintained for 3-5 hours to complete impregnation; s32, secondary roasting and dipping; roasting the blank subjected to primary impregnation for the second time, cooling to 220-; s33, roasting and dipping for three times; roasting the blank after primary impregnation for three times, cooling to 200-220 ℃, putting into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing to 1-2MPa, and maintaining the pressure for 3-5 hours to finish impregnation; s34; roasting for four times; and S4, graphitizing. The ultrahigh-power graphite electrode prepared by the method has low porosity and excellent performance.
Description
Technical Field
The invention relates to the technical field, in particular to an ultrahigh-power graphite electrode and a preparation method thereof.
Background
The graphite electrode is a high-temperature resistant graphite conductive material which is prepared by using petroleum coke and pitch coke as aggregates and coal pitch as an adhesive through the steps of raw material calcination, crushing and grinding, batching, kneading, molding, roasting, dipping, graphitization and machining, and is called an artificial graphite electrode (graphite electrode for short).
The development of electric furnace steelmaking technology (the large-scale electric furnace, the improvement of electric power of unit furnace capacity and the use of a direct current electric arc furnace) continuously puts new requirements on the variety and the performance of graphite electrodes, and the adoption of the high-power and ultrahigh-power electric furnace steelmaking can shorten the melting time of furnace charge, improve the production efficiency, reduce the power consumption and reduce the consumption of the graphite electrodes.
The ultrahigh-power graphite electrode has large diameter, so that impregnation liquid is not easy to permeate during impregnation, the impregnation effect is poor, and the porosity is high.
Disclosure of Invention
In view of this, the technical problem to be solved by the present invention is to provide an ultrahigh power graphite electrode and a preparation method thereof, and the prepared ultrahigh power graphite electrode has a good impregnation effect and low porosity.
The technical scheme of the invention is realized as follows:
a preparation method of an ultrahigh-power graphite electrode comprises the following steps:
s1, blending, crushing and screening;
s2, kneading and molding to obtain a blank;
s3, roasting and dipping;
s31, roasting and dipping for the first time;
after the green body is roasted, the temperature is reduced to 240-260 ℃, the green body is placed into an impregnation container, impregnation liquid A is injected after vacuum pumping, the pressure is increased by 2-3MPa, and the pressure is maintained for 3-5 hours to complete impregnation;
s32, secondary roasting and dipping;
roasting the blank subjected to primary impregnation for the second time, cooling to 220-;
s33, roasting and dipping for three times;
roasting the blank after primary impregnation for three times, cooling to 200-220 ℃, putting into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing to 1-2MPa, and maintaining the pressure for 3-5 hours to finish impregnation;
s34; roasting for four times;
and S4, graphitizing.
In this application, because the size of ultrahigh power graphite electrode is great, consequently carry out the cubic flooding to improve the flooding effect, the pressurization of cubic flooding reduces gradually, because after each impregnation roasting, the impregnating solution has solidified in the space department of graphite electrode, and subsequent flooding is impregnated in the space that the impregnating solution formed of the previous time, consequently can reduce the temperature and the pressure of follow-up flooding, with the reduction energy consumption.
Preferably, the ingredients comprise the following raw materials in parts by weight:
65-70 parts of needle coke, 3-5 parts of raw fragments and 20-25 parts of binder;
the particle size composition of the needle coke comprises:
less than 0.075mm in 30-40 wt%, 0.075-0.5mm in 25-35 wt%, and needle coke below 22mm in the rest.
Preferably, the impregnation liquid A is prepared from the following raw materials in parts by weight:
95-100 parts of impregnating asphalt and 10-13 parts of oleic acid.
Preferably, the impregnation liquid B is prepared from the following raw materials in parts by weight:
95-100 parts of impregnating asphalt and 8-10 parts of oleic acid.
Preferably, the impregnation liquid C is prepared from the following raw materials in parts by weight:
95-100 parts of impregnating asphalt and 5-8 parts of oleic acid.
In this application, impregnating solution A is the modified impregnating solution, adds oleic acid into impregnating pitch, and the permeability that can effectively improve impregnating pitch permeates a period of time under the high temperature normal pressure.
Preferably, the impregnation liquid B is prepared from the following raw materials in parts by weight:
95-100 parts of impregnating asphalt and 2-4 parts of oleic acid.
In this application, the flooding liquid is modified flooding liquid, adds oleic acid into impregnating pitch, and the permeability that can effectively improve impregnating pitch permeates a period under the high temperature normal pressure.
In the application, the oleic acid content of the impregnating solution B is lower than that of the impregnating solution A, after the impregnating solution A is impregnated and dried, secondary impregnation is carried out through the impregnating solution B, and after primary impregnation is carried out, the impregnating solution A is filled in the pores of the graphite electrode, so that the impregnating solution B is mainly filled into the pores formed by the impregnating solution A during secondary impregnation, and the impregnating solution B is not required to have too high permeability.
If the oleic acid content in the impregnating solution B is too high, surface surplus is formed on the surface of the impregnating asphalt, so that the oxidation resistance of the impregnating solution B is influenced, and therefore, the oleic acid content of the impregnating solution B is lower than that of the impregnating solution A, so that the permeability and the oxidation resistance can be balanced.
Similarly, the oleic acid content of the impregnation fluid C is lower than that of the impregnation fluid B.
The invention also provides an ultrahigh-power graphite electrode which is prepared by the preparation method of any one of the ultrahigh-power graphite electrodes.
The ultrahigh-power graphite electrode prepared by the preparation method provided by the invention has low porosity and excellent performance.
Detailed Description
The technical solutions in the embodiments of the present invention will be 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 preparation method of an ultrahigh-power graphite electrode comprises the following steps:
s1, blending, crushing and screening;
s2, kneading and molding to obtain a blank;
s3, roasting and dipping;
s31, roasting and dipping for the first time;
roasting the blank, cooling to 260 ℃, putting the blank into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing at 3MPa, and maintaining the pressure for 3 hours to finish impregnation;
s32, secondary roasting and dipping;
roasting the blank body subjected to primary impregnation for the second time, cooling to 240 ℃, putting into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing at 2.5MPa, and maintaining the pressure for 3 hours to finish impregnation;
s33, roasting and dipping for three times;
roasting the blank body after primary impregnation for three times, cooling to 220 ℃, putting into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing at 2MPa, and maintaining the pressure for 3 hours to finish impregnation;
s34; roasting for four times;
and S4, graphitizing.
The ingredients are prepared from the following raw materials in parts by weight:
65 parts of needle coke, 3 parts of raw broken pieces and 20 parts of binder;
the particle size composition of the needle coke comprises:
less than 40% of needle coke with diameter of 0.075mm, 35% of needle coke with diameter of 0.075-0.5mm, and the rest of needle coke with diameter of 22 mm.
The impregnation liquid A is prepared from the following raw materials in parts by weight:
95 parts of impregnating asphalt and 10 parts of oleic acid.
The impregnation liquid B is prepared from the following raw materials in parts by weight:
95 parts of impregnating asphalt and 8 parts of oleic acid.
The impregnation liquid C is prepared from the following raw materials in parts by weight:
95 parts of impregnating asphalt and 5 parts of oleic acid.
The invention also provides an ultrahigh-power graphite electrode which is prepared by the preparation method of any one of the ultrahigh-power graphite electrodes.
Example 2
A preparation method of an ultrahigh-power graphite electrode comprises the following steps:
s1, blending, crushing and screening;
s2, kneading and molding to obtain a blank;
s3, roasting and dipping;
s31, roasting and dipping for the first time;
after the green body is roasted, the temperature is reduced to 240 ℃, the green body is placed into an impregnation container, impregnation liquid A is injected after vacuumizing, the pressure is increased by 2MPa, and the pressure is maintained for 5 hours to complete impregnation;
s32, secondary roasting and dipping;
roasting the blank body subjected to primary impregnation for the second time, cooling to 220 ℃, putting into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing to 1.5MPa, and maintaining the pressure for 5 hours to finish impregnation;
s33, roasting and dipping for three times;
roasting the blank body after primary impregnation for three times, cooling to 200 ℃, putting into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing at 1MPa, and maintaining the pressure for 5 hours to finish impregnation;
s34; roasting for four times;
and S4, graphitizing.
The ingredients are prepared from the following raw materials in parts by weight:
65 parts of needle coke, 3 parts of raw broken pieces and 20 parts of binder;
the particle size composition of the needle coke comprises:
less than 30% of needle coke with a particle size of 0.075-0.5mm, and less than 25% of needle coke with a particle size of 22 mm.
The impregnation liquid A is prepared from the following raw materials in parts by weight:
100 parts of impregnating asphalt and 13 parts of oleic acid.
The impregnation liquid B is prepared from the following raw materials in parts by weight:
100 parts of impregnating asphalt and 10 parts of oleic acid.
The impregnation liquid C is prepared from the following raw materials in parts by weight:
100 parts of impregnating asphalt and 8 parts of oleic acid.
The invention also provides an ultrahigh-power graphite electrode which is prepared by the preparation method of any one of the ultrahigh-power graphite electrodes.
Example 3
A preparation method of an ultrahigh-power graphite electrode comprises the following steps:
s1, blending, crushing and screening;
s2, kneading and molding to obtain a blank;
s3, roasting and dipping;
s31, roasting and dipping for the first time;
after the green body is roasted, the temperature is reduced to 250 ℃, the green body is placed into an impregnation container, impregnation liquid A is injected after vacuumizing, the pressure is increased by 2.5MPa, and the pressure is maintained for 4 hours to complete impregnation;
s32, secondary roasting and dipping;
roasting the blank subjected to primary impregnation for the second time, cooling to 230 ℃, putting into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing at 2MPa, and maintaining the pressure for 4 hours to finish impregnation;
s33, roasting and dipping for three times;
roasting the blank body after primary impregnation for three times, cooling to 210 ℃, putting into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing at 1.5MPa, and maintaining the pressure for 4 hours to finish impregnation;
s34; roasting for four times;
and S4, graphitizing.
The ingredients are prepared from the following raw materials in parts by weight:
68 parts of needle coke, 4 parts of raw fragments and 22 parts of binder;
the particle size composition of the needle coke comprises:
less than 40% of needle coke with diameter of 0.075mm, 35% of needle coke with diameter of 0.075-0.5mm, and the rest of needle coke with diameter of 22 mm.
The impregnation liquid A is prepared from the following raw materials in parts by weight:
98 parts of impregnating pitch and 11 parts of oleic acid.
The impregnation liquid B is prepared from the following raw materials in parts by weight:
98 parts of impregnating pitch and 9 parts of oleic acid.
The impregnation liquid C is prepared from the following raw materials in parts by weight:
98 parts of impregnating pitch and 6 parts of oleic acid.
The invention also provides an ultrahigh-power graphite electrode which is prepared by the preparation method of any one of the ultrahigh-power graphite electrodes.
Example 4
A preparation method of an ultrahigh-power graphite electrode comprises the following steps:
s1, blending, crushing and screening;
s2, kneading and molding to obtain a blank;
s3, roasting and dipping;
s31, roasting and dipping for the first time;
after the green body is roasted, the temperature is reduced to 240 ℃, the green body is placed into an impregnation container, impregnation liquid A is injected after vacuumizing, the pressure is increased by 2MPa, and the pressure is maintained for 4 hours to complete impregnation;
s32, secondary roasting and dipping;
roasting the blank body subjected to primary impregnation for the second time, cooling to 220 ℃, putting the blank body into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing at 2MPa, and maintaining the pressure for 4 hours to finish impregnation;
s33, roasting and dipping for three times;
roasting the blank body after primary impregnation for three times, cooling to 210 ℃, putting into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing at 1.5MPa, and maintaining the pressure for 4 hours to finish impregnation;
s34; roasting for four times;
and S4, graphitizing.
The ingredients are prepared from the following raw materials in parts by weight:
69 parts of needle coke, 3 parts of raw broken pieces and 22 parts of binder;
the particle size composition of the needle coke comprises:
less than 40% of needle coke with diameter of 0.075mm, less than 30% of needle coke with diameter of 0.075-0.5mm, and the rest is needle coke with diameter of less than 22 mm.
The impregnation liquid A is prepared from the following raw materials in parts by weight:
97 parts of impregnating pitch and 13 parts of oleic acid.
The impregnation liquid B is prepared from the following raw materials in parts by weight:
97 parts of impregnating pitch and 9 parts of oleic acid.
The impregnation liquid C is prepared from the following raw materials in parts by weight:
97 parts of impregnating pitch and 6 parts of oleic acid.
The invention also provides an ultrahigh-power graphite electrode which is prepared by the preparation method of any one of the ultrahigh-power graphite electrodes.
Finally, it is to be noted that: the above description is only a preferred embodiment of the present invention, and is only used to illustrate the technical solutions of the present invention, and not to limit the protection scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.
Claims (6)
1. A preparation method of an ultrahigh-power graphite electrode is characterized by comprising the following steps:
s1, blending, crushing and screening;
s2, kneading and molding to obtain a blank;
s3, roasting and dipping;
s31, roasting and dipping for the first time;
after the green body is roasted, the temperature is reduced to 240-260 ℃, the green body is placed into an impregnation container, impregnation liquid A is injected after vacuum pumping, the pressure is increased by 2-3MPa, and the pressure is maintained for 3-5 hours to complete impregnation;
s32, secondary roasting and dipping;
roasting the blank subjected to primary impregnation for the second time, cooling to 220-;
s33, roasting and dipping for three times;
roasting the blank after primary impregnation for three times, cooling to 200-220 ℃, putting into an impregnation container, vacuumizing, injecting impregnation liquid A, pressurizing to 1-2MPa, and maintaining the pressure for 3-5 hours to finish impregnation;
s34; roasting for four times;
and S4, graphitizing.
2. The preparation method of the ultra-high power graphite electrode as claimed in claim 1, wherein the ingredients comprise the following raw materials by weight:
65-70 parts of needle coke, 3-5 parts of raw fragments and 20-25 parts of binder;
the particle size composition of the needle coke comprises:
less than 0.075mm in 30-40 wt%, 0.075-0.5mm in 25-35 wt%, and needle coke below 22mm in the rest.
3. The method for preparing the ultrahigh-power graphite electrode according to claim 1, wherein the impregnating solution A comprises the following raw materials in parts by weight:
95-100 parts of impregnating asphalt and 10-13 parts of oleic acid.
4. The method for preparing the ultrahigh-power graphite electrode according to claim 1, wherein the impregnating solution B comprises the following raw materials in parts by weight:
95-100 parts of impregnating asphalt and 8-10 parts of oleic acid.
5. The method for preparing the ultra-high power graphite electrode according to claim 1, wherein the impregnation liquid C comprises the following raw materials in parts by weight:
95-100 parts of impregnating asphalt and 5-8 parts of oleic acid.
6. An ultra-high power graphite electrode, characterized by being produced by the method for producing an ultra-high power graphite electrode according to any one of claims 1 to 5.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113999011A (en) * | 2021-12-14 | 2022-02-01 | 中钢集团南京新材料研究院有限公司 | Short-process graphite preparation method |
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| CN113999011A (en) * | 2021-12-14 | 2022-02-01 | 中钢集团南京新材料研究院有限公司 | Short-process graphite preparation method |
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