Process for preparing needle coke raw material by using medium and low temperature coal tar

Abstract

The invention relates to a process for preparing a needle coke raw material by using medium and low temperature coal tar, which comprises the following steps: 1) distilling the medium and low temperature coal tar, separating to obtain heavy distillate with the temperature more than 350DEG C; 2) sending the heavy distillate of the medium and low temperature coal tar to a reactor, under the existence of a catalyst, introducing hydrogen into the reactor, performing hydropyrolysis on the heavy distillate, wherein the catalyst is a Fe catalyst and the mass of the catalyst accounts for 0.01-3% of mass of the heavy distillate; the pressure during the hydropyrolysis is 7-12 MPa and the temperature is 350-550 DEG C; 3) sending the products after hydropyrolysis in the step 2) to a separator, and separating to obtain lower oil and higher oil; and 4) performing physical separation on the higher oil, and removing the catalyst. According to the hydropyrolysis treatment of the medium and low temperature coal tar, the content of condensed polycyclic aromatic hydrocarbons can be greatly increased and the raw material suitable for preparing needle coke can be obtained.

Description

technical field

[0001] The invention belongs to the field of coal chemical industry, and in particular relates to a process for preparing coal-based needle coke raw materials from coal tar. Background technique

[0002] Needle coke is a high-quality material for manufacturing high-power and ultra-high-power electrodes. Graphite electrodes made of needle coke have strong thermal shock resistance, high mechanical strength, good oxidation performance, low electrode consumption and large allowable current density, etc. advantage. At present, needle coke has been widely used in high-tech fields such as electric furnace steelmaking, manufacturing deceleration materials for nuclear reactors, and manufacturing ultra-high-power electrodes for rocket launches.

[0003] The needle coke currently produced can be divided into petroleum-based needle coke and coal-based needle coke according to the different raw materials used, but both coal-based and petroleum-based needle coke have the ...

Examples

Embodiment 1

[0034] The process for preparing needle coke raw material using medium and low temperature tar described in this embodiment includes:

[0035] (1) Distill the medium and low temperature tar in the distillation tower to separate the heavy fraction above 350°C;

[0036] Each index of described heavy distillate is as follows:

[0037] QI: 3.2wt%, TI: 5.6wt%, S concentration: 0.26wt%.

[0038](2) The heavy fraction of the medium and low temperature tar is sent to a hydrogenation reactor, and the heavy fraction of the medium and low temperature tar is hydrothermally decomposed in the presence of an iron-based catalyst. The mass of the iron-based catalyst accounts for 0.01% of the heavy fraction mass of the medium and low temperature tar; the iron-based catalyst described in the present embodiment is FeS 2 ;

[0039] The pressure condition of the hydrothermal decomposition is 7MPa, and the temperature is 350°C; the feed rate of the medium and low temperature tar is 10kg / h, and th...

Embodiment 2

[0047] The process for preparing needle coke raw material using medium and low temperature tar described in this embodiment includes:

[0048] (1) Distill the medium and low temperature tar in the distillation tower to separate the heavy fraction above 350°C;

[0049] Each index of described heavy distillate is as follows:

[0050] QI: 2.9 wt%, TI: 5.2 wt%, S: 0.24 wt%.

[0051] (2) The heavy fraction of the medium and low temperature tar is sent to a hydrogenation reactor, and the heavy fraction of the medium and low temperature tar is hydrothermally decomposed in the presence of an iron-based catalyst. The mass of the iron-based catalyst accounts for 3% of the heavy fraction mass of the medium and low temperature tar, the iron-based catalyst described in this embodiment is FeS 2 ;

[0052] The pressure condition of the hydrothermal decomposition is 10MPa, and the temperature is 450°C; the feed rate of the medium and low temperature tar is 20kg / h, and the volume of hydroge...

Embodiment 3

[0060] The process for preparing needle coke raw material using medium and low temperature tar described in this embodiment includes:

[0061] (1) Distill the medium and low temperature tar in the distillation tower to separate the heavy fraction above 350°C;

[0062] Each index of described heavy distillate is as follows:

[0063] QI: 2.9 wt%, TI: 5.2 wt%, S: 0.24 wt%.

[0064] (2) The heavy fraction of the medium and low temperature tar is sent to a hydrogenation reactor, and the heavy fraction of the medium and low temperature tar is hydrothermally decomposed in the presence of an iron-based catalyst. The mass of the iron-based catalyst accounts for 0.8% of the heavy fraction mass of the medium and low temperature tar, the iron-based catalyst described in this embodiment is FeS 2 ;

[0065] The pressure condition of the hydrothermal decomposition is 12MPa, and the temperature is 550°C; the feed rate of the medium and low temperature tar is 20kg / h, and the volume of hydro...

technical field

[0001] The invention belongs to the field of coal chemical industry, and in particular relates to a process for preparing coal-based needle coke raw materials from coal tar. Background technique

[0002] Needle coke is a high-quality material for manufacturing high-power and ultra-high-power electrodes. Graphite electrodes made of needle coke have strong thermal shock resistance, high mechanical strength, good oxidation performance, low electrode consumption and large allowable current density, etc. advantage. At present, needle coke has been widely used in high-tech fields such as electric furnace steelmaking, manufacturing deceleration materials for nuclear reactors, and manufacturing ultra-high-power electrodes for rocket launches.

[0003] The needle coke currently produced can be divided into petroleum-based needle coke and coal-based needle coke according to the different raw materials used, but both coal-based and petroleum-based needle coke have the ...

Examples

Embodiment 1

[0034] The process for preparing needle coke raw material using medium and low temperature tar described in this embodiment includes:

[0035] (1) Distill the medium and low temperature tar in the distillation tower to separate the heavy fraction above 350°C;

[0036] Each index of described heavy distillate is as follows:

[0037] QI: 3.2wt%, TI: 5.6wt%, S concentration: 0.26wt%.

[0038](2) The heavy fraction of the medium and low temperature tar is sent to a hydrogenation reactor, and the heavy fraction of the medium and low temperature tar is hydrothermally decomposed in the presence of an iron-based catalyst. The mass of the iron-based catalyst accounts for 0.01% of the heavy fraction mass of the medium and low temperature tar; the iron-based catalyst described in the present embodiment is FeS 2 ;

[0039] The pressure condition of the hydrothermal decomposition is 7MPa, and the temperature is 350°C; the feed rate of the medium and low temperature tar is 10kg / h, and th...

Embodiment 2

[0047] The process for preparing needle coke raw material using medium and low temperature tar described in this embodiment includes:

[0048] (1) Distill the medium and low temperature tar in the distillation tower to separate the heavy fraction above 350°C;

[0049] Each index of described heavy distillate is as follows:

[0050] QI: 2.9 wt%, TI: 5.2 wt%, S: 0.24 wt%.

[0051] (2) The heavy fraction of the medium and low temperature tar is sent to a hydrogenation reactor, and the heavy fraction of the medium and low temperature tar is hydrothermally decomposed in the presence of an iron-based catalyst. The mass of the iron-based catalyst accounts for 3% of the heavy fraction mass of the medium and low temperature tar, the iron-based catalyst described in this embodiment is FeS 2 ;

[0052] The pressure condition of the hydrothermal decomposition is 10MPa, and the temperature is 450°C; the feed rate of the medium and low temperature tar is 20kg / h, and the volume of hydroge...

Embodiment 3

[0060] The process for preparing needle coke raw material using medium and low temperature tar described in this embodiment includes:

[0061] (1) Distill the medium and low temperature tar in the distillation tower to separate the heavy fraction above 350°C;

[0062] Each index of described heavy distillate is as follows:

[0063] QI: 2.9 wt%, TI: 5.2 wt%, S: 0.24 wt%.

[0064] (2) The heavy fraction of the medium and low temperature tar is sent to a hydrogenation reactor, and the heavy fraction of the medium and low temperature tar is hydrothermally decomposed in the presence of an iron-based catalyst. The mass of the iron-based catalyst accounts for 0.8% of the heavy fraction mass of the medium and low temperature tar, the iron-based catalyst described in this embodiment is FeS 2 ;

[0065] The pressure condition of the hydrothermal decomposition is 12MPa, and the temperature is 550°C; the feed rate of the medium and low temperature tar is 20kg / h, and the volume of hydro...