A temperature-controlling measure for the hydrogenation slurry bed reactor and its design method and use

Abstract

A temperature-controlling measure for a hydrogenation slurry bed reactor has three control points that are set from low to high: cold hydrogen is injected automatically when the system reaches control point 1; cold oil is injected automatically when the system reaches control point 2; each pressure relief is opened automatically when the system reaches control point 3. The pressure relief point is set before and/or after the circulation pump of the reactor if internal circulation is set in the reactor; the pressure relief point is set at the reactor bottom if the internal circulation is not set; at least one pressure relief valve is set at each pressure relief point.

Claims

1. A temperature-controlling measure of a hydrogenation slurry bed reactor, characterized in that: three control points are set in turn from low to high: cold hydrogen is injected automatically when the reaction system reaches control point 1; cold oil is injected automatically when the system reaches control point 2; each pressure relief point is opened automatically when the system reaches control point 3; the control point 1 is: 425 C.T<440 C. and/or P19 MPa; the control point 2 is: 440 C.T<455 C. and/or P19 MPa; the control point 3 is: T455 C. and/or P20 MPa; the pressure relief point is set before and/or after the circulation pump of the reactor if internal circulation is set in the reactor; the pressure relief point is set at the bottom of the reactor if the internal circulation is not set in the reactor; at least one pressure relief valve is set at each pressure relief point.

2. The temperature-controlling measure according to claim 1, wherein the hydrogenation reactors are used in series, the number of series is 2-4, and the number of reactors with pressure relief points is more than 1.

3. An temperature-controlling measure according to claim 1, wherein the pressure relief valve is controlled by the temperature or pressure in the reactor, the number of temperature measurement points is at least 1, the number of pressure measurement points is at least 1, a temperature self-control valve and/or hand control valve are set; the pressure relief valve opens when the reactor operates at more than 455 C. or the operating pressure is more than 20 MPa; an alarm triggers and the pressure relief valve opens when the system reaches either condition mentioned above alarm and start; all the control valve will open and the whole device will be shut down when the reactor temperature is more than 465 C. and the operating pressure is more than 21.5 MPa.

4. An temperature-controlling measure according to claim 1, wherein the overtemperature and overpressure signals are transmitted to DCS and/or SIS systems simultaneously, in order to initiate corresponding measures.

5. An temperature-controlling measure according to claim 1, wherein the pressure relief valve also receive other pressure relief signal instructions.

6. An temperature-controlling measure according to claim 1, wherein the signal instructions received are a signal of an abnormal pressure at the outlet of the feed pump of the reactor, the signal of abnormal pressure at the outlet of the circulating hydrogen compressor or the fresh hydrogen compressor, or the abnormal reaction in the reactor.

7. A hydrogenation slurry bed reactor, said hydrogenation slurry bed reactor adopting the temperature-controlling measure according to claim 1.

8. The use of the hydrogenation reactor according to claim 7, comprising the process of hydrogenation of heavy oil, coal direct liquefaction, oil and coal mixing co-refining; the hydrogenation of heavy oil refers to the process refines one or combinations of the feedstocks including crude oil, atmospheric residue, vacuum residue, catalytic slurry, deoiled asphalt and coal tar; the oil and coal mixing co-refining process refers to the process which refines one or combinations of crude oil, atmospheric residue, vacuum residue, catalytic slurry, deoiled asphalt and coal tar, with one or combinations of lignite and bituminous coal; the proportion of crude oil to coal is from 30:70 up to 97:3.

9. The design method of the temperature-controlling measure for the hydrogenation slurry bed reactor, characterized in that: the measure is designed as follow: three control points are set in turn from low to high: the cold hydrogen is injected automatically when the system reaches the control point 1; the cold oil is injected automatically when the system reaches the control point 2; each pressure relief point is opened automatically when the system reaches the control point 3; the control point 1 is: 425 C.T<440 C. and/or P19 MPa; the control point 2 is: 440 C.T<455 C. and/or P19 MPa; the control point 3 is: T455 C. and/or P20 MPa; the pressure relief point is set before and/or after the circulation pump of the reactor if internal circulation is set in the reactor; the pressure relief point is set at the bottom of the reactor if internal circulation is not set in the reactor; at least one pressure relief valve is set at each pressure relief point.

Description

FIGURE

[0023] FIG. 1 shows a scheme of the reactor according to present the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0024] In order to explain the invention better, the combination of FIG. 1 and an embodiment will be illustrated below.

Embodiment

[0025] This embodiment introduces a slurry bed hydrogenation reactor in one stage of the coal and oil mixing co-refining process. The pressure relief point is set at the inlet of the circulating pump, the amount of the pressure relief valve 7 is one, the depressurizing line 6 is the pipeline of the pressure relief valve 7, which is used to discharge the released medium.

[0026] The feedstock 2 enters the reactor 1 through the feeding outlet of the feed distributor 3, in addition, there is an internal circulation system, which includes the circulating feed distributor 4, the circulation pump 5 and the inlet of internal circulation 9 in the reactor.

[0027] The operating temperature of the outlet is not more than 455 C. during the normal operation of the reactor 1. As the hydrocracking reaction is exothermic, the temperature measurement point is set at the closest point from the outlet of the reactor 8 to detect the maximum operating temperature of the reactor. In order to avoid the failure measurement of the thermometer or sensor, three thermometers are set up by taking temperature readings from two of the three thermometers. The cold hydrogen is injected automatically when 425 C. is reached; the cold oil is injected automatically when 440 C. is reached; when 455 C. is reached, the alarm is triggered and the pressure relief valve 7 is started to open with transferring the signal to the DCS and SIS system. The pressure relief valve 7 is fully opened automatically when the operating temperature exceeds 465 C. and the device shuts down.

[0028] The operating pressure at the inlet is not more than 18.5 MPa when the reactor 1 is operated normally. As the flow direction is from bottom to top, the pressure point is set at the closest point of the inlet of the reactor, i.e. the feeding outlet of the feed distributor 3, to detect the maximum operating pressure of the reactor. In order to avoid the failure measurement of the pressure gauge or sensor, three pressure gauges are set up by taking readings from two of the three thermometers. The pressure relief valve is started to open (controlling the temperature by controlling the pressure) when the operation pressure exceeds 20 MPa, and the signal is transferred to the DCS and SIS system. The pressure relief valve is fully opened and the device shuts down when the pressure exceeds 21.5 MPa. The pressure relief valve also accepts other signals outside the reaction system that need to start the depressurizing, such as the signal of an abnormal pressure at the outlet of the feed pump of the reactor, the signal of an abnormal pressure at the outlet of the circulating hydrogen compressor or the fresh hydrogen compressor, or the abnormal reaction in the reactor.

[0029] This embodiment achieves a positive application effect in the hydrogenation slurry bed reactor through the practical verification in production. The measure designed is simple with high degree of automation, and it could also improve the safety of the reactor and production process and ensure the reactor has no safety issue for long term.

[0030] The embodiment above is only an optimal specific embodiment of this invention, but the scope of the invention is not limited to it. Any changes which can be easily considered or replaced in the disclosure scope of the invention by a person skilled in this art, should be covered within the protection scope of the invention. As a result, the protection scope of the present invention shall be based on the protection scope of the claims.