CN104673341A

CN104673341A - Method for preparing needle coke

Info

Publication number: CN104673341A
Application number: CN201510034574.5A
Authority: CN
Inventors: 张宏利; 郭小宇; 张冲; 周超强; 王丛; 张娟; 卓强
Original assignee: Huludao Design Institute
Current assignee: Huludao Design Institute
Priority date: 2015-01-23
Filing date: 2015-01-23
Publication date: 2015-06-03

Abstract

The invention provides a method for preparing needle coke. The method comprises the following steps: heating the purified petroleum slurry to the temperature of 390 to 410 DEG C in a high-pressure reactor, stirring and carrying out a passivation reaction under the conditions of the pressure of 1MPa and the rotating speed of 150 revolutions per minute under the protection of nitrogen, and preparing mesophase pitch; stirring and charring the mesophase pitch under the conditions of the temperature of 490-510 DEG C and the constant pressure of 1MPa for 2-5 hours, and discharging the gas, thereby obtaining the needle coke. The method disclosed by the invention is simple in process, convenient and safe to operate and high in controllability, and is different from the previous method for directly producing the needle coke and refers to a two-step method. The method comprises the following steps: preparing the mesophase pitch with excellent performance; and generating high-quality needle coke to serve as the raw material of high-power and ultra-high-power graphite electrodes and carbon fibers. The method is applied to a method for preparing the needle coke by utilizing the petroleum slurry.

Description

A kind of method preparing needle coke

Technical field

What the present invention relates to is refining of petroleum field, is that mesophase pitch prepared by raw material with oil slurry oil, and then obtains the method for high-quality needle coke.A kind of specifically method preparing needle coke.

Background technology

Needle coke is the fine quality greatly developed in 20 century 70 carbon materialses, there is thermal expansivity low, low-sulfur, low ash content, low-metal content, the advantages such as easy greying and high connductivity, mainly for the production of the superpower of electric steel, ultra-high power graphite electrode and extraordinary carbon product, are also the type materials for the production of the fire-resistant furnace charge of brush, battery and high.Although started to walk in the eighties in last century domestic research, for various reasons, fails to produce high performance needle coke product.The product of current domestic production can only be used for ordinary electrode and use, and ultra-high power graphite electrode still needs a large amount of import.

Needle coke production technique mainly contains the following aspects.

One, raw materials pretreatment.Often containing a small amount of impurity in the selected raw material of oil system needle coke, so centrifugation, filtration, the method removing such as settlement separate can be selected.But also contain quinoline insolubles (QI) except containing except impurity in the selected raw material of coal-based needle coke, QI component is mixed in and is unfavorable for spherular growth between microsphere, melts also, the highly organized coke structure of anisotropy is can not get, so need to carry out refining to remove QI component to the raw material of coal-based needle coke after solidification.Equchi, US), Patent:5695631,1997-06-13; Bai Peiwan etc., tar needle-shape coke Review Study. Shanxi Datong University's journal: natural science edition.

2007,23 (3): 53 ~ 56, there is people gravity settling and centrifugal separation process to be combined and pre-treatment is carried out to coal tar, improve QI decreasing ratio, in coal tar, add organic mixed solvent improves its viscosity and density simultaneously, improves separating effect further, makes QI content lower than 0.1%.(Luo Daocheng etc. coal tar removes the purifying treatment research [J] of quinoline insolubles (QI). Coal Chemical Industry, 2008,135 (2): 11 ~ 13.).

Two, the expansion of raw material.Someone is by the coal tar that mixes in 4:1 ratio and petroleum residual oil.

Be 480 DEG C in temperature, pressure is carry out coking under 1.6 MPa, generates the needle coke of low thermal coefficient of expansion (CTE); (Zhang Huaiping. coal tar and petroleum residual oil Co carbonization prepare needle coke. refining of petroleum and chemical industry, 2005,36 (2): 21 ~ 26).Looking into celebrating virtue etc. mixes in vacuum residuum (VR) by the FCC slurry oil of 30%, finds that FCC slurry oil has relaxed the pyrolysis rate of residual oil effectively, has all prepared the needle coke of high-quality.Look into celebrating virtue etc., vacuum residuum mixes different substances together FCC slurry oil and prepares needle coke. charcoal element technology, 2002,121(4): 10 ~ 14.

Three, delayed coking process.Delayed coking is the crucial workshop section in whole production process of needle coke.

In actual production process, except careful selection raw material, also need the impact considering carbonization condition, make material maintain metastable state, produce the needle coke of high-quality.

Four, calcine.In calcination process, the heteroatomss such as the sulphur of effusion and nitrogen can cause irreversible volumetric expansion " brilliant swollen " occurs during greying, make finished product inside there is certain defect, cause quality product to decline, product can be caused time serious to ftracture.The people such as Yoichi Kawano have studied the effective restraining effect to " brilliant swollen " such as metal, nonmetal oxide, boric acid and the composite swollen inhibitor of crystalline substance, and propose its inhibiting mechanism.（Yoichi Kawano et al,Puffing behavior during the graphitization of coal-tar-based needle coke in Pregnated with iron (Ⅱ) sulfate and boric acid, Carbon,2000,38:759～765）。

Summary of the invention

For the shortcoming that prior art exists, the present invention proposes a kind of method preparing needle coke.The method is by joining in autoclave by raw material, and heating, adds mesophase pitch, and light constituent is reclaimed in condensation, solves the technical problem utilizing mesophase pitch to produce needle coke.

The scheme that technical solution problem of the present invention adopts is:

Oil slurry oil after purification passivation is heated 390 ~ 410 DEG C in autoclave; with nitrogen protection; passivation reaction is stirred under 1MPa pressure and 150r/min speed conditions; prepare mesophase pitch; mesophase pitch is carried out stirring charing 2 ~ 5h under 490 ~ 510 DEG C of conditions with constant voltage 1Mpa; Exhaust Gas, prepares needle coke.

1, oil slurry Passivation Treatment: take setting quality oil slurry directly join in autoclave, be filled with 1MPa nitrogen protection gas, adjustment stir speed (S.S.) at 150r/min and start heating.At constant voltage 1MPa or under the condition of boosting, be warmed up to 390 ~ 410 DEG C.

2, prepare mesophase pitch: be incubated 60 ~ 90 minutes at 390 ~ 410 DEG C of temperature after, stop heating, gas reactor is discharged, form mesophase pitch.

3, needle coke is prepared: prepared mesophase pitch raw material is put into autoclave, be warmed up to 490 ~ 510 DEG C, be cured crosslinking reaction, after reaction terminates, stop stirring, insulation 1 ~ 4h, after gas reactor is discharged, Temperature fall, in reaction process, pressure controls all the time at 1MPa, and the light constituent produced in reaction process is reclaimed in condensation, in still, residuum is obtained needle coke.

Positively effect, the inventive method technique is simple, easy and safe to operate, controllability is strong, the different method in the past directly generating needle coke, but method in two steps, first the mesophase pitch that processability is excellent, then generates high quality needle-type coke, can be used as the raw material of superpower and ultra-high power graphite electrode and carbon fiber etc.The suitable method application as producing needle coke.

Embodiment

To selected oil slurry oil after filtration, extracting or underpressure distillation carry out purification process.

Preferred version:

First: at mesophasespherule generation disintegration generation mesophase pitch until in the process of solidification, gas is had to flow to certain orientation continuously in reactor, this air-flow has certain flow rate, can apply enough shearing forces to mesophase pitch but not produce disturbance, mesophase pitch molecule is solidified in nematic ordered arrangement, finally be generated as needle coke, this needle coke performance is more excellent.

Second: production high-quality needle coke, very crucial to the selection of raw material, require that sulphur, nitrogen, bituminous matter, ash content, metal impurities massfraction are low, aromaticity content is high, wherein will based on three rings and four Polycyclic aromatic hydrocarbons.From the situation of domestic catalytic slurry, comparatively large from the requirement gap meeting These parameters, sulfur nutrient is generally higher, therefore needs the catalytic slurry to producing needle coke to refine further.

3rd: owing to being alternating temperature operation, the deep fat wave overflowed in reactor is dynamic comparatively large, and during high temperature section, deep fat gas linear speed significantly increases, and causes and rushes tower phenomenon, rises violent, therefore operationally control further, can have lifting to quality product in the temperature short period of time.

Specific embodiment is as follows:

Embodiment 1: get the oil slurry oil of 600g after filtration treatment, put into reactor, sealing, drains air with nitrogen purging, keeps 1Mpa constant voltage.Control rotating speed of agitator at 150r/min, within early stage 300 DEG C, computer heating control is at 5 DEG C/about min; Middle and later periods controls, at 1 ~ 2 DEG C/min, to be warmed up to 400 DEG C, insulation 2h.After being discharged by gas reactor, take out product after Temperature fall, obtain the wide area type mesophase pitch that mesophase spherule content is higher, softening temperature is 235 DEG C, mesophase spherule content about 70%.Keep 1Mpa pressure in reactor, rotating speed of agitator 150r/min, is warmed up to 490 DEG C, after curing cross-linking reaction terminates, and stops stirring, and insulation 4h, obtain mesophase spherule content 100%, the needle coke product of excellent property, solid productive rate is 64%.

Embodiment 2: get the oil slurry oil of 580g after furfural extraction process, put into reactor, drain air with nitrogen purging, ensures stopping property, relies on reaction from boosting to 4Mpa.Control rotating speed of agitator at 150r/min, within early stage 300 DEG C, computer heating control is at 5 DEG C/about min; Middle and later periods controls, at 1 ~ 2 DEG C/min, to be warmed up to 420 DEG C, and insulation 90min, obtain the fairshaped mesophase pitch of mesophase spherule content 80%, softening temperature is 265 DEG C.Maintenance reacting kettle inner pressure is 1Mpa, and rotating speed of agitator is 150r/min, is warmed up to 510 DEG C, and insulation 2h, obtain mesophase spherule content 100%, the needle coke product that performance is comparatively excellent, solid productive rate is 71%.

Below illustrate invention has been, but the present invention is not limited to described embodiment, those of ordinary skill in the art also can make all equivalent modification or replacement under the prerequisite without prejudice to spirit of the present invention, and these equivalent modification or replacement are all included in the application's claim limited range.

Claims

1. prepare a method for needle coke, it is characterized in that following these steps to obtain:

1), oil slurry Passivation Treatment: the oil slurry taking setting quality directly joins in autoclave, be filled with 1MPa nitrogen protection gas, adjustment stir speed (S.S.) at 150r/min and start heating, constant voltage 1MPa or from boosting condition under, be warmed up to 390 ~ 410 DEG C;

2), prepare mesophase pitch: be incubated 60 ~ 90 minutes at 390 ~ 410 DEG C of temperature after, stop heating, gas reactor is discharged, form mesophase pitch;

3), needle coke is prepared: prepared mesophase pitch raw material is put into autoclave, be warmed up to 490 ~ 510 DEG C, be cured crosslinking reaction, after reaction terminates, stop stirring, insulation 1 ~ 4h, after gas reactor is discharged, Temperature fall, in reaction process, pressure controls all the time at 1MPa, and the light constituent produced in reaction process is reclaimed in condensation, in still, residuum is obtained needle coke.

2. a kind of method preparing needle coke according to claim 1, is characterized in that: described oil slurry is multiple turpentole slurry oil.