A coke drum safety interlock system based on sis system

Abstract

The utility model discloses a coke tower safety interlocking system based on SIS system relates to the technical field of petroleum chemical industry, including detection instrument unit, safety instrument system unit and execution equipment unit, the detection instrument unit includes the multiple temperature detection instrument and multiple pressure detection instrument of setting on the coke tower tower top pipeline and tower bottom pipeline, safety instrument system unit with detection instrument unit signal connection is used for receiving the signal that temperature detection instrument and pressure detection instrument sent, the utility model discloses a tower top pressure interlocking module, tower top temperature interlocking module, tower bottom pressure interlocking module and tower bottom temperature interlocking module are configured to three take two redundancy mode, have realized to single instrument fault's fault tolerance, avoided the system malfunction or refusal action of the instrument false report, greatly improved the reliability of whole safety interlocking system.

Description

Technical Field

[0001] This utility model relates to the field of petrochemical technology, and in particular to a safety interlocking system for coke towers based on the SIS system. Background Technology

[0002] Delayed coking is an important heavy oil processing technology in the oil refining industry. As its core equipment, the coking tower is subject to dangerous factors such as high temperature, high pressure, flammability and explosion during operation. Especially during start-up, shutdown and switching operations, safety accidents can easily occur due to misoperation.

[0003] In the prior art, such as the patent with publication number CN104460563A, a delayed coking coke tower sequential control system based on a DCS system is disclosed, which can avoid safety accidents caused by valve misoperation to a certain extent. However, this DCS system can only function when the sequential control system and related equipment are operating normally. When the unit is started or stopped, the sequential control system is not in use, or there is a fault in the system equipment, there is still a risk of misoperation, which may lead to serious accidents such as fires and explosions.

[0004] Therefore, it is necessary to provide a safety interlocking system that can still ensure operational safety when the sequential control system is unavailable. Utility Model Content

[0005] This utility model provides a coke tower safety interlocking system based on the SIS system, which ensures the safety of the production system when the unit start-up and shutdown sequence control system is not in use or when there are problems with the system equipment, and will not cause accidents due to misoperation.

[0006] To achieve the above objectives, this utility model provides a coke tower safety interlock system based on a SIS system, comprising a detection instrument unit, a safety instrument system unit, and an execution device unit. The detection instrument unit includes multiple temperature and pressure sensors installed on the top and bottom pipelines of the coke tower. The safety instrument system unit is signal-connected to the detection instrument unit and receives signals from the temperature and pressure sensors. The execution device unit includes a top cover machine and a bottom cover machine for the coke tower, both of which are signal-connected to the safety instrument system unit. The execution device unit receives signals from the safety instrument system unit. The detection instrument unit, safety instrument system unit, and execution device unit are connected via signal lines.

[0007] Preferably, the temperature and pressure sensors in the instrumentation unit are configured with a two-out-of-three redundancy scheme.

[0008] Preferably, the input terminal of the safety instrumented system unit is simultaneously connected to the output signals of the tower top pressure detection instrument, the tower top temperature detection instrument, and the tower bottom temperature detection instrument, and the output terminal of the safety instrumented system unit is connected to the top cover machine.

[0009] Preferably, the input terminal of the safety instrumented system unit is simultaneously connected to the output signals of the tower bottom pressure detection instrument, the tower top temperature detection instrument, and the tower bottom temperature detection instrument, and the output terminal of the safety instrumented system unit is connected to the bottom cover machine.

[0010] Preferably, the input terminal of the safety instrument system unit is connected to a position sensor for detecting the open state of the top cover machine, and the output terminal of the safety instrument system unit is connected to the bottom cover machine.

[0011] Preferably, the position sensor is configured with a 2-out-of-3 redundancy scheme.

[0012] Compared with related technologies, the coke tower safety interlocking system based on the SIS system provided by this utility model has the following beneficial effects:

[0013] This utility model provides a safety interlocking system for coke towers based on the SIS system. By constructing a dedicated hardware interlocking circuit independent of the DCS / sequential control system, it effectively prevents serious safety accidents caused by personnel misoperation in opening the top or bottom cover machine when the unit is started or stopped, or when the sequential control system is not in use or bypassed, thus fundamentally eliminating the risk of high-temperature oil and gas leakage.

[0014] By employing a three-out-of-two redundancy configuration for the tower top pressure interlock module, tower top temperature interlock module, tower bottom pressure interlock module, and tower bottom temperature interlock module, fault tolerance for single instrument failures is achieved, avoiding system malfunctions or failures to operate due to instrument false alarms, and greatly improving the reliability of the entire safety interlock system.

[0015] By simultaneously incorporating multiple parameters such as tower top pressure, tower top temperature, and tower bottom temperature into the logical judgment of the safety instrument system unit, a comprehensive and indirect judgment of the tower's internal operating conditions is achieved. This ensures that before the cover is allowed to be opened, the critical isolation valves are in a safe position and there is no dangerous medium inside the tower, providing a multi-layered safety assurance mechanism.

[0016] By setting up two optional hardware connection schemes, a flexible and reliable protection path is provided for the opening of the bottom cover machine, which is based on direct judgment of the pressure and temperature at the bottom of the tower or on the interlocking of the opening status of the top cover machine. This adapts to different operating habits and safety strategies, while ensuring that the opening of the bottom cover machine is under strict safety constraints no matter how it is operated. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present utility model;

[0018] Figure 2 This is a diagram of the interlocking logic of the top cover mechanism according to Embodiment 1 of this utility model;

[0019] Figure 3 This is a schematic diagram of the bottom cover interlocking logic structure of Embodiment 1 of this utility model;

[0020] Figure 4 This is a schematic diagram of the structure of Embodiment 2 of this utility model;

[0021] Figure 5 This is a diagram illustrating the interlocking logic of the top cover mechanism in Embodiment 2 of this utility model.

[0022] Figure 6 This is a schematic diagram of the bottom cover interlocking logic structure of Embodiment 2 of this utility model.

[0023] The diagram is labeled as follows: 100, coke tower; 101, top cover machine; 102, bottom cover machine; 2, top pressure interlock module; 3, top temperature interlock module; 4, bottom pressure interlock module; 5, bottom temperature interlock module; 6, top status interlock module. Detailed Implementation

[0024] The specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. The core structure of this utility model lies in a complete hardware safety loop formed by connecting a detection instrument unit, a safety instrument system unit, and an execution device unit through signal lines.

[0025] Example 1

[0026] like Figure 1 and Figure 3 As shown, in this embodiment, the system mainly relies on direct monitoring of the temperature and pressure of the coke tower 100 to ensure safety.

[0027] The detection instrument unit includes: a pressure detection instrument installed on the top pipeline of coke tower 100, forming the top pressure interlock module 2 and a temperature detection instrument forming the top temperature interlock module 3; and a pressure detection instrument installed on the bottom pipeline, forming the bottom pressure interlock module 4 and a temperature detection instrument forming the bottom temperature interlock module 5. All these detection instruments are preferably configured using a two-out-of-three redundancy scheme.

[0028] The input terminal of the safety instrumented system unit is connected to the output terminal of all the aforementioned detection instrument units via a signal cable.

[0029] The execution equipment unit includes a top cover machine 101 and a bottom cover machine 102 of the coke tower 100, and their control loops are connected to the output of the safety instrument system unit.

[0030] Three pressure sensors are installed at the top of the tower, namely PT-1A, PT-1B, and PT-1C; three pressure sensors are installed at the bottom of the tower, namely PT-2A, PT-2B, and PT-2C; three temperature sensors are installed at the top of the tower, namely TT-1A, TT-1B, and TT-1C; and three temperature sensors are installed at the bottom of the tower, namely TT-2A, TT-2B, and TT-2C.

[0031] like Figure 2 As shown, the interlocking logic of the top cover machine 101 is as follows: The input terminal of the safety instrumented system unit simultaneously receives signals from the top pressure interlocking module 2, the top temperature interlocking module 3, and the bottom temperature interlocking module 5. Only when the signals from these three interlocking modules meet preset safety conditions—for example, at least two of the three pressure sensors at the top of the tower have pressure values ​​≤ 0.02 MPaG, at least two of the three temperature sensors at the top of the tower have temperature values ​​≤ 130℃, and at least two of the three temperature sensors at the bottom of the tower have temperature values ​​≤ 130℃—will the safety instrumented system unit send an open signal to the control circuit of the top cover machine 101.

[0032] like Figure 3 As shown, the interlocking logic of the bottom cover machine 102 is as follows: The input terminal of the safety instrumented system unit simultaneously receives signals from the bottom pressure interlocking module 4, the top temperature interlocking module 3, and the bottom temperature interlocking module 5. When the signals from these three interlocking modules all meet the preset safety conditions, for example, at least two of the three pressure sensors at the bottom of the tower have pressure values ​​≤ 0.07 MPaG, at least two of the three temperature sensors at the top of the tower have temperature values ​​≤ 130℃, and at least two of the three temperature sensors at the bottom of the tower have temperature values ​​≤ 130℃, the safety instrumented system unit sends an opening signal to the bottom cover machine 102.

[0033] Example 2

[0034] like Figure 4 and Figure 6 As shown, in this embodiment, the safety interlock conditions of the bottom cover machine 102 mainly depend on the state of the top cover machine 101.

[0035] The system configuration of this embodiment is basically the same as that of Embodiment 1, including a detection instrument unit, a safety instrument system unit, and an execution device unit. The difference is that a tower top status interlocking module 6 is added. This unit consists of a position sensor installed on the top cover machine 101 to detect its open state, and this unit is also preferably configured in a three-out-of-two redundancy manner.

[0036] There are three position sensors, located in SQ-A, SQ-B, and SQ-C respectively.

[0037] The output signal of the tower top status interlock module 6 is connected to the input terminal of the safety instrument system unit.

[0038] In this embodiment, the interlocking logic of the top cover machine 101 is exactly the same as that in Embodiment 1, ensuring the safety of the top cover machine 101 itself when it is opened.

[0039] The interlocking logic for the bottom cover machine 102 is as follows: The input terminal of the safety instrumented system unit receives a signal from the tower top status interlocking module 6. When at least two of the three position sensors detect that the top cover machine 101 is in the open state, the safety instrumented system unit confirms that the top cover machine 101 is in a safe open state and then sends an open signal to the bottom cover machine 102. This solution provides a more direct and simpler safety assurance path based on equipment status interlocking.

[0040] The above description is merely a preferred embodiment of this utility model, but the protection scope of this utility model is not limited to the above embodiments. Any equivalent substitutions or modifications made by those skilled in the art within the technical scope disclosed in this utility model, based on the technical solution and inventive concept of this utility model, should be included within the protection scope of this utility model.

Claims

1. A coke drum safety interlock system based on SIS system, characterized in that, It includes detection instrument units, safety instrument system units, and actuator units; The detection instrument unit includes multiple temperature detection instruments and multiple pressure detection instruments installed on the pipelines at the top and bottom of the coke tower. The safety instrument system unit is signal-connected to the detection instrument unit and is used to receive signals from the temperature detection instrument and the pressure detection instrument. The execution device unit includes a top cover machine and a bottom cover machine for the coke tower. The top cover machine and the bottom cover machine are respectively signal-connected to the safety instrument system unit. The execution device unit is used to receive signals from the safety instrument system unit. The detection instrument unit, safety instrument system unit, and execution device unit are connected by signal lines.

2. The SIS system based coke drum safety interlock system of claim 1, wherein, The temperature and pressure sensors in the instrumentation unit are both configured with a 2-out-of-3 redundancy scheme.

3. The SIS system based coke drum safety interlock system of claim 2, wherein, The input terminal of the safety instrumented system unit is simultaneously connected to the output signals of the tower top pressure detection instrument, the tower top temperature detection instrument, and the tower bottom temperature detection instrument, and the output terminal of the safety instrumented system unit is connected to the top cover machine.

4. The SIS system based coke drum safety interlock system of claim 2, wherein, The input terminal of the safety instrumented system unit is simultaneously connected to the output signals of the tower bottom pressure detection instrument, the tower top temperature detection instrument, and the tower bottom temperature detection instrument, and the output terminal of the safety instrumented system unit is connected to the bottom cover machine.

5. The SIS system based coke drum safety interlock system of claim 2, wherein, The input terminal of the safety instrument system unit is connected to a position sensor for detecting the open state of the top cover machine, and the output terminal of the safety instrument system unit is connected to the bottom cover machine.

6. The SIS system based coke drum safety interlock system of claim 5, wherein, The position sensor is configured with a 2-out-of-3 redundancy scheme.

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