JPS5896680A - Method for preventing coking in coal liquefaction apparatus - Google Patents

Abstract

PURPOSE:To shorten the residence time of liquefied product in the coal liquefaction process, by stirring the produced liquefied product, thereby suppressing the coking, preventing the blockage of the coal liquefaction appratus and the pipings, and facilitating the continuous operation of the apparatus. CONSTITUTION:In the coal liquefaction process comprising the treatment of coal with a solvent in hydrogen atmosphere at high temperature and pressure, the liquefied product discharged from the reactor 4 is charged through the charging pipe 9 into the high pressure vaporliquid separating vessel 6 without cooling. The residence time of the liquefied product in the high pressure vapor-liquid separating vessel 6 is adjusted to a level to prevent the thermal polymerization and coking of the product at a temperature of as high as 400-450 deg.C, and the liquefied product is stirred by reduction gas blown into the product through the stirring gas pipe 7. The coking in the coal liquefaction apparatus can be prevented by this process.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquefied product produced when coal is subjected to a sintering reaction using a solvent J611L/% under high temperature and high pressure in a hydrogen atmosphere to produce a casing base material. Prevent Coal II by stirring and reducing residence time
This article concerns a method for preventing clogging of II conversion equipment and piping, improving continuous operation of the equipment, and improving thermo-economic efficiency.Recently, as an energy measure, coal The development of liquefaction technology is being promoted, and various types of reefs have been designed, installed on reefs, or are in operation. A representative example of the conventional coal liquefaction process is explained with reference to Figure IIK to make it easier to understand.It is carried out by the method shown in sheet 7o of Figure 1. First, the pulverized coal, which is usually finer than 200 mesh and has a moisture content of 2x or less, and the recovery circulation ii+n agent are slurried in a slurry tank z1, and the resulting slurry is sent to a preheater 3 by a mesh 1-charge pump 2. At that time, high-pressure hydrogen-rich reducing gas is mixed with the nut. Approximately 300~ with preheater 3
A mixture of heat and reducing gas preheated to 500° C. was heated to a temperature of 500° C. in reactor 4.

℃ and a pressure of about 50 to 500 atm. The liquefied reaction mixture flows out from the upper part of the reaction wrap, is cooled by a cooler 5"r!, and then led to a gas-liquid separation high-pressure receiver 6, where it is produced. The gas and the remaining reduced GANU are separated.＠ In this way, in the conventional coal liquefaction process, a cooler 5 is installed which is thermoeconomically disadvantageous. Excessive light oil separation and thermal polymerization in the liquefied product are prevented by cooling the liquefied reaction mixture, and
This is to prevent clogging of the sake and maintain continuous operation of the equipment.

However, once cooled by a cooler during the process,
If the T-core is then reheated in the process after the extraction pipe, which is disadvantageous in terms of thermoeconomics, there is a problem in that one cooler equipment cost is required at P1.

In view of the above-mentioned problems, the present invention prevents booking by introducing a gas-liquid separation high-pressure receiver during the process without first cooling it as in the past, and adding an operation here that has not been done in the past. T6 aims to prevent clogging of the separation high-pressure receiver and the discharging vibrator, improve the continuous operation of the device, and provide the T67j method with advantageous thermoeconomic efficiency.
A preferred embodiment of a process implementing the method according to the invention will now be described in detail with reference to the accompanying drawings, in which: FIG.

FIG. 2 shows an embodiment of the present invention. The process up to reactor 4 is carried out in the same manner as the conventional process shown in FIG. 811. The liquefied reaction mixture flowing out from reactor 4 is In order to utilize heat effectively, the liquefied reaction mixture is introduced into the gas-liquid separation high-pressure receiver 6 through the charging pipe 9 without being cooled. 9' in figure 3
The liquefied reaction mixture introduced into the gas-liquid separation high-pressure receiver 6 is not cooled, so the produced gas and produced light substances are separated in a high temperature state. Oil and reducing gas are separated.In this state, the liquefied product undergoes thermal polymerization and condensation! Due to the concentration, blockage occurs in the liquid layer of the gas-liquid separation high-pressure receiver @6, the discharge pipe 8, etc. Therefore, the gas-liquid separation high pressure receiver shown in FIGS. 2 and 3! ! 1i1
In order to reduce the residence time of the liquid layer of the liquefied product in step 6 to prevent the above phenomenon from occurring, it is necessary to reduce the amount of liquefied product at a moderate speed (T). α2〜S壓−
1 preferably o, s~1ψ- and -S of the reducing gas
It is preferable that the pipe 7 be inserted into the liquid phase portion of the gas-liquid separation high-pressure receiver 6 to stir the liquefied product.

As mentioned above, in order to further increase the stirring effect, if the charging pipe 9' is connected to the liquid sealing part of the gas-liquid separation high-pressure receiver 6, it will work together with the injection of reducing male through the stirring gas pipe. can produce even greater effects. In this way, gawking and thermal polymerization can be prevented and continuous operation can be made possible.
[The coke-nullage-like material that has accumulated at the bottom of the separation high-pressure receiver II6 can be discharged from #E from the 10th section of the Pussy F Kunpaig.

In the conventional cooling process of 51 Wk, the temperature of the gas-liquid separation high-pressure receiver 6 is 330~RS Oc, and the transfer rate is 0.05
~0.1 Yer @ In this state, if the temperature f is raised to 600℃ or higher, gas-liquid separation high-pressure receiver II will occur due to thermal polymerization and Gorkin l.
6. Blockage occurred in one of the extraction pipes, making it impossible to operate continuously for more than 30 days. However, 1. As is clear from the above, according to the present invention, the transfer speed of the liquefied product can be increased. Reduce residence time in the gas-liquid separation high-pressure receiver,
Coking and thermal polymerization can be prevented by forcibly stirring the liquefied product in the high-pressure receiver for gas-liquid separation, so blockages can be prevented without thermoeconomically disadvantageous cooling as in the past. This makes it possible to operate continuously without any problems.

Next, the method of the present invention will be explained in detail with reference to examples.T6o In the conventional process of installing a cooler, the temperature in the gas-liquid separation high-pressure receiver is 330 to 350 C, and the product transfer rate is 0.6
5 to 0.1 m/-, and the residence time is 10 to 30 minutes. Under these conditions, if the temperature reaches 400 C or higher, the gas-liquid separation high-pressure receiver, outlet pipe, etc. will be clogged due to coking and thermal polymerization. Therefore, in the present invention, the 430 to 450 CM2g that has been transferred to the gas-liquid separation high-pressure receiver is
The transfer rate of the reaction product was increased to 0.5 to 1.0 m/-, the residence time was decreased to 1 to 3 minutes, and the reducing gas was transferred to 50 to 10 m/- (17 s) using the stirring gas bar, Eve 7.
The liquefied product was stirred. In order to reduce the residence time, the dimensions of the gas-liquid separation high-pressure receiver were changed as follows compared to the conventional one. That is, the diameter of the liquid layer portion was approximately 1/3, and the volume was approximately 1/10.

As a result, even if the gas-liquid separation high-pressure receiver is operated at a temperature of 4001 or higher, which is the same as that flowing out from the reactor, without cooling, no thermal polymerization will occur. It has become possible to operate continuously for more than 30 days without causing blockages.

[Brief explanation of drawings]

Figure 1 shows a flow sheet for a conventional coal liquefaction process according to the present invention, and Figure 3 shows a specific example of a gas-liquid separation high-pressure receiver. Diagram 0 Explanation of symbols 1- Soft freeing tank, 2- Slurry charge pump, 3- Preheater, 4- Reactor, 5- Cooler, 6...
・Gas-liquid separation high-pressure receiver, 7-Ganu pipe for stirring, 8-Take-out pipe, 9.9'-Pipe with scissors, 10-Puto-Dakun pipe Patent applicant Kawasaki Steel Co., Ltd. Kanesha Kawatetsu Chemical Co., Ltd. Agent Patent attorney Nozomu Watanabe - (100-100 2 figures, 3 figures, 3 figures)

Claims (1)

[Claims] In Pro-7, coal is liquefied by solvent treatment under high temperature and high pressure in a water-volume atmosphere. , 1-degree air purification that does not cause thermal polymerization or co-ordering at a temperature of 400 to 450°C of the liquefied product charged from the reactor without cooling in the gas-liquid separation high-pressure receiver - retention in the high-pressure receiver Method for preventing coal sintering in coal casing equipment by stirring the liquefied product over time and turning it into mold.