High-integrity protection system for reaction container

Abstract

The invention discloses a reaction vessel high integrity protection system, which comprises a reaction vessel and an HIPS system connected with the reaction vessel, the HIPS system comprises a switch valve system, a reaction vessel liquid level monitoring system and an HIPS control system; the switch valve systems are two sets of same systems which are connected in parallel, each set of switch valve system comprises a fault opening type valve, a reset switch which is connected with the fault opening type valve and is used for resetting the valve, and a valve position switch which is connected with the fault opening type valve and is used for controlling the fault opening type valve to be opened and closed; a liquid outlet of the fault opening type valve is connected with the pressure vessel, the reaction vessel liquid level monitoring system comprises a plurality of liquid level transmitters connected with the reaction vessel and liquid level signal measuring elements connected with the liquid level transmitters, the HIPS control system is in signal connection with the reset switch, the valve position switch and the liquid level signal measuring elements, and the parallel switch valve system is connected with the liquid level signal measuring elements. And the risk of operation refusal caused by a single valve fault can be eradicated, and the risk of safety production can be avoided to the maximum extent.

Description

Technical Field

[0001] The invention relates to the field of reaction vessel protection systems, and in particular to a high-integrity protection system for reaction vessels. Background Art

[0002] High integrity protection system (HIPS) is a more extensive protection system. In addition to the safety equipment used by HIPS to protect high-pressure gas or liquid pipeline systems, it is also used to prevent process variables such as liquid level, temperature, flow, etc. from exceeding the normal range and causing major losses, thereby protecting the safety of personnel and equipment. HIPS systems are usually composed of liquid level sensors or temperature sensors or flow sensors, controllers, actuators, etc., which can realize real-time monitoring and control of the protected system. When these process variables exceed the preset values, the HIPS system will quickly and automatically switch the inlet valve to a safe state to prevent major losses in the protected system.

[0003] The valve body used in the common HIPS system is complex in structure, difficult to manufacture and maintain, and has a high failure rate, which seriously affects the safety and reliability of the system. In addition, the system has poor redundancy and only has a single hydraulic switch, which is prone to the risk of refusal to operate and cannot meet the HIPS safety level requirements. Summary of the invention

[0004] In view of the above problems, the present invention provides a high-integrity protection system for a reaction vessel, which has a simple structure and high reliability, can eliminate the risk of refusal to operate, and can meet the safety level requirements.

[0005] The technical solution of the present invention is:

[0006] A high integrity protection system for a reaction vessel, comprising a reaction vessel and a HIPS system connected to the reaction vessel, wherein the HIPS system comprises a switch valve system, a reaction vessel liquid level monitoring system and a HIPS control system;

[0007] The switch valve system is two identical systems connected in parallel, each of which includes a fail-open valve, a reset switch connected to the fail-open valve for resetting the valve, and a valve position switch connected to the fail-open valve for controlling the switch of the fail-open valve, and the liquid outlet of the fail-open valve is connected to the reaction container;

[0008] The reaction vessel liquid level monitoring system comprises a plurality of liquid level transmitters connected to the reaction vessel and a liquid level signal measuring element connected to each liquid level transmitter;

[0009] The HIPS control system is connected with the reset switch, the valve position switch, and the liquid level signal measuring element signal.

[0010] The fail-open valve is a ball valve.

[0011] The number of the reset switches is two, and the two reset switches are connected in series.

[0012] The valve position switch comprises a valve opening indication switch and a valve closing indication switch, and the valve opening indication switch and the valve closing indication switch are an integrated structure.

[0013] The HIPS control system has a built-in redundant CPU and a redundant IO module, and the HIPS control system is externally connected to two redundant data communication loops, ModBus1# and ModBus2#.

[0014] The reset switch is a solenoid valve.

[0015] The reset switch is provided with instrument air for driving the switch of the fail-open type valve.

[0016] The beneficial effects of the present invention are:

[0017] By setting up a parallel switch valve system, the risk of refusal to operate due to a single valve failure can be eliminated, and the risk of safe production can be avoided to the greatest extent. By controlling the switch valve system, the irreversible production process can be protected, and the key equipment and processes can be ensured to have no risk of empty tanks and flow interruption. The switch valve system is equipped with a reset switch and a valve position switch, and at the same time cooperates with the HIPS control system and the liquid level signal measurement unit to respond quickly, which can improve system safety and rapid data connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of a high integrity protection system for a reaction vessel described in an embodiment of the present invention.

[0019] Description of reference numerals:

[0020] 1 is a reaction vessel, 2 is a HIPS system, 3 is a switch valve system, 4 is a reaction vessel liquid level monitoring system, 5 is a HIPS control system, 31 is a fail-open valve, 32 is a reset switch, 33 is a valve position switch, 41 is a liquid level signal measuring element, and 42 is a liquid level transmitter. DETAILED DESCRIPTION

[0021] The embodiments of the present invention will be further described below in conjunction with the accompanying drawings.

[0022] Example:

[0023] like Figure 1As shown, a high integrity protection system for a reaction vessel comprises a reaction vessel 1 and a HIPS system 2 connected to the reaction vessel 1, wherein the HIPS system 2 comprises a switch valve system 3, a reaction vessel liquid level monitoring system 4 and a HIPS control system 5;

[0024] The switch valve system 3 is two identical systems connected in parallel, each switch valve system 3 comprises a fail-open valve 31, a reset switch 32 connected to the fail-open valve 31 for resetting the valve, and a valve position switch 33 connected to the fail-open valve 31 for controlling the switch of the fail-open valve 31, and the liquid outlet of the fail-open valve 31 is connected to the reaction container 1;

[0025] The reaction vessel liquid level monitoring system 4 comprises a plurality of liquid level signal measuring elements 41 connected to the reaction vessel 1 and a liquid level transmitter 42 connected to each liquid level signal measuring element 41;

[0026] The HIPS control system 5 is connected to the reset switch 32 , the valve position switch 33 , and the liquid level transmitter 42 via signals.

[0027] The working principle of the above technical solution is as follows:

[0028] By setting up the parallel switch valve system 3, the risk of refusal to operate due to a single valve failure can be eliminated, and the risk of safe production can be avoided to the greatest extent. By controlling the switch valve system 3, the irreversible production process can be protected, and the key equipment and process can be ensured to be free of the risk of empty tanks and flow interruption. The switch valve system 3 is provided with a reset switch 32 and a valve position switch 33, and cooperates with the HIPS control system 5 and the liquid level transmitter 42 to respond quickly, thereby improving system safety and rapid data connection.

[0029] The specific embodiments are as follows:

[0030] In this embodiment, the fault-opening valve 31 is a ball valve, the reset switch 32 is two solenoid valves connected in series, and an instrument air is set on the reset switch 32. The valve position switch 33 includes a valve opening indication switch and a valve closing indication switch. The valve opening indication switch and the valve closing indication switch are an integrated structure. The HIPS control system 5 has a built-in redundant CPU and a redundant IO module. The HIPS control system is externally connected to two redundant data communication circuits ModBus1# and ModBus2#, and three groups of liquid level transmitters are set at the same time.

[0031] After the three liquid levels are set according to the low-low liquid level, the three-out-of-two and diagnostic functions are designed. One of the parallel fault-open valves is in a closed state under normal working conditions, and the other is in an open state. If the low-low liquid level is triggered, the solenoid valve is turned off, and the fault-open valve 31 and the reset switch 32 are in an open state by the spring-driven cylinder. At the same time, the FO (fault-open valve) logic can also be triggered by manually hitting the emergency stop button. When the process is normal, it is reset by the reset switch 32. The reset condition is that the opening of the fault-open valve should be fully open. After resetting, the parallel fault-open valve 31 will be closed, and the other fault-open valve 31 can adjust the opening to keep the equipment liquid level in a normal state. The logical operation is the core CPU computing unit of the HIPS control system and its input and output (IO) module, which can also be called a logic solver, loaded with the above-mentioned logic programs; ModBus1# and ModBus2# two communication loops are connected to the PCS control system in the central control room from the communication interface of the HIPS controller in a redundant manner to ensure that the signal can be transmitted in time and displayed and recorded.

[0032] The details are as follows:

[0033] The system is connected in front of the key reaction vessel 1 in the production process system as required. When working, the fluid enters through the normally open fail-open valve 31 according to the flow direction of the fluid. The level transmitter 41 monitors the liquid level of the fluid in the reaction vessel 1, and outputs a signal to the positioner of the normally open fail-open valve 31 through the central control system. Then, the I / P electrical converter adjusts its opening to adjust the flow entering the reaction vessel 1, ensuring that the liquid level runs above the alarm limit of the three level transmitters 42. At this time, the other fail-open valve 31 remains closed. Once any two level transmitters 42 detect that the liquid level is lower than the set value, the redundant HIPS control system 5 outputs an emergency valve opening signal through a three-out-of-two (2oo3) voting operation, so that the reset switch 32 cuts off the instrument air IA leading to the normally open fail-open valve 31, and releases the instrument air in the actuator of the other fail-open valve 31, and the normally open fail-open valve 31 will be quickly opened under the action of the actuator spring force. At the same time, the emergency valve opening signal output by the HIPS control system 5 will also cause the solenoid valve to cut off the instrument air IA leading to the other fault-open type valve 31, and release the instrument air in the actuator, and the other fault-open type valve 31 will be quickly opened under the action of the actuator spring force. With the rapid opening of the two cut-off valves and ball valves, the pipeline fluid will be quickly replenished into the reaction vessel 1 to avoid the empty tank of the reaction vessel 1, thereby affecting the downstream process interruption and causing production and equipment losses. Since there are three liquid level transmitters 41, any failure will not cause the system to be unavailable; the reset switch 32 is two in series, and any failure to operate will not cause the instrument air leading to the normally open fault-open type valve 31 actuator to be unable to be cut off; the HIPS controller is a redundant CPU and redundant IO module, with high fault tolerance and safety. The HIPS controller provides two redundant data communication loops, ModBus1# and ModBus2#, to the outside, which can provide reliable real-time communication to the outside for monitoring of this system.

[0034] This system can ensure that key equipment and processes do not have the risk of empty tanks and flow interruption. At the same time, it can be adjusted daily through fault-open valves during normal production. It has a strong protective effect on irreversible production processes, and the full opening time is less than 3 seconds in abnormal situations. The mechanical parts of the ball valve trim and the actuator are also relatively simple, which is conducive to maintenance. In addition, the parallel arrangement of the two valves can completely avoid the risk of refusal to operate caused by mechanical failure of a single valve, thereby affecting safe production. The extensive use of electrical components can enable the entire system to meet the SIL3 level requirements. The HIPS control system also improves the system security and the ability to quickly connect data, and can connect to the PCS system data monitoring needs of the central control room.

[0035] The above-mentioned embodiments only express the specific implementation of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A high integrity protection system for a reaction vessel, comprising a reaction vessel and a HIPS system connected to the reaction vessel, characterized in that: The HIPS system includes a switch valve system, a reaction vessel liquid level monitoring system and a HIPS control system; The switch valve system is two identical systems connected in parallel, each of which includes a fail-open valve, a reset switch connected to the fail-open valve for resetting the valve, and a valve position switch connected to the fail-open valve for controlling the switch of the fail-open valve, and the liquid outlet of the fail-open valve is connected to the reaction container; The reaction vessel liquid level monitoring system comprises a plurality of liquid level transmitters connected to the reaction vessel and a liquid level signal measuring element connected to each liquid level transmitter; The HIPS control system is connected with the reset switch, the valve position switch, and the liquid level signal measuring element signal.

2. A high integrity protection system for a reaction vessel according to claim 1, characterized in that: The fail-open valve is a ball valve.

3. A high integrity protection system for a reaction vessel according to claim 1, characterized in that: The number of the reset switches is two, and the two reset switches are connected in series.

4. A high integrity protection system for a reaction vessel according to claim 1, characterized in that: The valve position switch comprises a valve opening indication switch and a valve closing indication switch, and the valve opening indication switch and the valve closing indication switch are an integrated structure.

5. A high integrity protection system for a reaction vessel according to claim 1, characterized in that: The HIPS control system has a built-in redundant CPU and a redundant IO module, and the HIPS control system is externally connected to two redundant data communication loops, ModBus1# and ModBus2#.

6. A high integrity protection system for a reaction vessel according to claim 1, characterized in that: The reset switch is a solenoid valve.

7. A high integrity protection system for a reaction vessel according to claim 1, characterized in that: The reset switch is provided with instrument air for driving the switch of the fail-open type valve.

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