A calcium carbide silo safety protection system

Abstract

The present invention discloses a safety protection system for calcium carbide silos, which relates to the field of chemical engineering technology. It includes a control system and a temperature detection system, an acetylene C2H2 monitoring system, a smoke monitoring system, an oxygen monitoring system, a dust concentration monitoring system, a pressure protection system, a material level monitoring system, an explosion protection system, and a nitrogen protection system connected to the control system. The control system is configured with an alarm, and the control system includes a host computer of a computer control system, a data acquisition box connected to the host computer, and a PLC control box. The nitrogen protection system is connected to the PLC control box. By implementing this technical solution, the technical problem that the existing calcium carbide silos cannot achieve full-process automated monitoring and protection can be effectively solved, so as to enable the calcium carbide silos to operate safely and smoothly, change passive maintenance to active prevention, minimize the operating labor intensity and safety hazards of the staff, eliminate potential safety threats to the calcium carbide silos, achieve full-process automation, and have good popularization and application value.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical engineering, and more specifically, to a safety protection system for a calcium carbide silo. Background Art

[0002] Acetylene plays a very important role in chemical production, and the calcium carbide silo is an important calcium carbide storage device in the acetylene production process. Existing calcium carbide silos have a large volume and can store thousands of tons of calcium carbide. However, existing calcium carbide silo protection systems are all designed according to traditional practices, with separate nitrogen protection, oxygen and acetylene gas alarm monitoring, ventilation measures in case of emergencies, etc. However, the inventors of this application found in the practical process that the existing calcium carbide silo protection system cannot achieve real-time monitoring of the working state of the equipment. Since calcium carbide is afraid of water and reacts with water to release acetylene, it is extremely easy to cause fires and explosions. Moreover, when the calcium carbide itself has serious dust, it can cause calcium carbide dust explosions. The existing calcium carbide silo protection system is not automated enough. Often, repair measures can only be taken after an accident, and it requires manual judgment and monitoring before making relevant responses. The safety protection monitoring of calcium carbide silos has not yet kept up with the pace of full-process automated monitoring and protection.

[0003] Therefore, in view of the above technical problems, it is urgent for those skilled in the art to research and design a safety monitoring and protection system for calcium carbide silos, which can achieve 24-hour real-time monitoring and tracking of the collected data of various sensors on site, data historical curves, equipment working states, and early warning of the occurrence of accidents, changing passive maintenance to preventive maintenance, being able to alarm in time when a fault occurs, remotely diagnose the faulty equipment, and can remotely guide the elimination of potential threats, realizing full-process automation. Summary of the Invention

[0004] To solve the above technical problems, the purpose of the present invention is to provide a safety protection system for a calcium carbide silo, aiming to provide a safety monitoring and protection system according to the structural design characteristics of the calcium carbide silo, so as to achieve safe and stable operation of the calcium carbide silo, change passive maintenance to active prevention, minimize the labor intensity and safety hazards of staff operations, eliminate potential safety threats in the calcium carbide silo, realize full-process automation, and have good popularization and application value.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A safety protection system for a calcium carbide silo includes a temperature detection system, an acetylene C2H2 monitoring system, a smoke monitoring system, an oxygen monitoring system, a dust concentration monitoring system, a pressure protection system, a material level monitoring system, an explosion protection system, a nitrogen protection system, and a control system;

[0007] The temperature detection system includes a temperature sensor installed inside the calcium carbide silo, and the temperature sensor is connected to the control system for monitoring the temperature change of the calcium carbide inside the silo;

[0008] The acetylene C2H2 monitoring system includes a C2H2 concentration detection sensor installed at the top of the calcium carbide silo. The C2H2 concentration detection sensor extends downward into the calcium carbide silo through a mounting accessory and is connected to the control system.

[0009] The smoke monitoring system includes a smoke detector installed at the top of the calcium carbide silo. The smoke detector extends downward into the calcium carbide silo through a mounting accessory and is connected to the control system to collect smoke information at the top of the calcium carbide silo and transmit the collected information to the control system.

[0010] The oxygen monitoring system includes an oxygen probe installed inside the top of the calcium carbide silo. The oxygen probe is connected to the control system and is used to monitor the oxygen content in the calcium carbide silo.

[0011] The dust concentration monitoring system includes a dust concentration sensor and a dust collector installed inside the top of the calcium carbide silo. The dust concentration sensor and the dust collector are respectively connected to the control system, so that when the dust concentration in the calcium carbide silo exceeds a preset value, the dust collector is triggered to start to dust the inside of the calcium carbide silo.

[0012] The pressure protection system includes a pressure sensor and a breathing safety valve configured in the calcium carbide silo. The pressure sensor and the breathing safety valve are respectively connected to the control system, so that when the pressure in the calcium carbide silo exceeds a preset value, the breathing safety valve is triggered to start to reduce the pressure inside the calcium carbide silo.

[0013] The material level monitoring system includes a high-low level gauge and a continuous level gauge vertically installed at the top of the calcium carbide silo. The high-low level gauge and the continuous level gauge are respectively connected to the control system.

[0014] The explosion-proof system includes multiple explosion-proof membranes configured at the top of the calcium carbide silo. The explosion-proof membranes are connected to the control system.

[0015] The nitrogen protection system includes an injection device and a buried pipe network arranged circumferentially around the calcium carbide silo body. The injection device is connected to the control system, so that when the detection parameters reach a preset threshold, the injection device is triggered to start and fill nitrogen into the calcium carbide silo through the buried pipe network.

[0016] Preferably, the embedded pipe network includes a gas sealing pipe network arranged at the lower conical hopper end of the calcium carbide silo, an air injection pipe network arranged at the cylindrical end of the calcium carbide silo and near the fold line of the conical hopper end, and a gas release pipe network arranged at the cylindrical end of the calcium carbide silo far from the conical hopper end; and a gas sealing valve, an air injection valve and a gas release valve connected to the control system are respectively configured on the gas sealing pipe network, the air injection pipe network and the gas release pipe network. Further preferably, one circle of gas sealing pipe network, two circles of air injection pipe network and one circle of gas release pipe network are designed to ensure that nitrogen can penetrate into the material as evenly as possible to the greatest extent and avoid the occurrence of gas channeling; the gas sealing pipe network, the air injection pipe network and the gas release pipe network in this technical solution are designed according to the structural characteristics of the calcium carbide silo, and this design is safe, reliable, ingenious and reasonable.

[0017] Preferably, the air injection device includes a nitrogen gas storage tank, a main pipeline connected to the nitrogen gas storage tank, and a pressure reducing valve configured on the main pipeline. The pressure reducing valve is connected to the control system, and the pipe networks of the gas sealing pipe network, the air injection pipe network and the gas release pipe network are sequentially communicated with the main pipeline from bottom to top.

[0018] Among them, the nitrogen purity provided by this technical solution should be ≥95%. Using the inert principle of nitrogen, high-purity nitrogen (≥95%) is used as the inerting gas source. When the measured parameters such as temperature and combustible gas in the safety monitoring system of the calcium carbide silo exceed the limit and alarm, the control system of the calcium carbide silo automatically starts the air injection device to fill the silo with nitrogen to dilute the concentration of combustible and explosive gases in the calcium carbide silo; thus, when the monitoring and protection system alarms, the combustible and explosive gases condensed above the calcium carbide layer inside the calcium carbide silo can be replaced in time to ensure the safety of the calcium carbide silo; and the full set of automatic control system can realize unmanned operation.

[0019] On the other hand, in this technical solution, a gas sealing valve, an air injection valve and a gas release valve connected to the control system are respectively configured on the gas sealing pipe network, the air injection pipe network and the gas release pipe network. Through the coordinated design of this part of the pipeline and valves, the inerting gas coming out of the nitrogen gas storage tank can be effectively controlled to enter the embedded pipe network through the calcium carbide silo; the inerting gas is stored in the main pipeline from bottom to top, and the control valves at different elevations near the main pipeline are automatically triggered according to the detection signals obtained by the control system to make this layer filled with high-purity inerting gas. In this way, the gas gradually increases from low to high to replace the combustible gas in the upper part of the material. The design of the pressure reducing valve in this technical solution is to reduce the pressure of the gas with pressure so that its pressure value meets the requirements. In this way, when the inerting gas is injected into the calcium carbide silo, it will not cause dusting; as described above, when the safety monitoring system of the calcium carbide silo finds an abnormality, the nitrogen protection system of the calcium carbide silo will automatically start the corresponding valves to intermittently inject nitrogen into the calcium carbide silo.

[0020] Preferably, the temperature detection system includes at least one set of multi-point temperature measurement cable sensors, which are hoisted at the top of the calcium carbide silo so that the multi-point temperature measurement cable sensors extend to the surface of the calcium carbide layer in the calcium carbide silo. Since once the acetylene gas generated by calcium carbide burns, it will inevitably cause a sharp rise in the internal temperature of the steel calcium carbide silo. Using the multi-point temperature measurement cable sensors arranged in this technical solution to monitor the temperature in the silo can effectively monitor the temperature change of the calcium carbide in the silo. Moreover, this sensor has the characteristics of being resistant to strong impact, easy to install, pluggable and easy to maintain, and is suitable for high-strength media such as uneven calcium carbide size and irregular shape. It can realize the positioning of the temperature measurement points, single-channel alarm and unified alarm effects; it is transmitted to the control system in time through the data acquisition box to display and alarm the monitored values, and judge the specific position of the temperature alarm point in the calcium carbide material according to the alarm signal.

[0021] Preferably, the acetylene C2H2 monitoring system includes at least one set of C2H2 concentration detection sensors, which are arranged on the top of the calcium carbide silo and extend downward into the calcium carbide silo by at least 1000 mm through the installation accessories. This technical solution has C2H2 gas concentration on-line analysis and detection software in the control system to set the C2H2 content in the calcium carbide silo <1% during normal operation. When the detection in the measurement range reaches the preset threshold, an alarm is triggered. When it exceeds 1.25%, the alarm is triggered. The control system prompts to monitor under normal circumstances. When there is a sign of increase in the C2H2 concentration and the control system of the calcium carbide silo monitors that its C2H2 concentration reaches the preset threshold, the injection valve of the corresponding nitrogen protection system of the calcium carbide silo is immediately triggered to start, increasing the amount of nitrogen injected into the calcium carbide silo until the monitored value of the acetylene C2H2 monitoring system returns to normal and the action of the nitrogen protection system stops.

[0022] Preferably, the smoke monitoring system includes at least one set of smoke detectors, which are arranged on the top of the calcium carbide silo and extend downward into the calcium carbide silo by at least 1000 mm through the installation accessories. Since once the acetylene generated by calcium carbide starts to burn, a large amount of thick smoke will inevitably be generated. In this technical solution, the smoke detector uses a switch quantity acquisition module to collect the smoke signal through the local data acquisition box on the top of the silo and transmit it to the silo control system in time.

[0023] Preferably, the oxygen monitoring system further includes oxygen concentration detectors installed on the top belt corridor and the bottom belt corridor of the calcium carbide silo, and the oxygen concentration detectors are connected to the control system. As a further preference, the oxygen concentration detector in this technical solution is built-in with a warning prompt and has the function of simultaneous alarm in the field and the control room; so that when the minimum safety content of 20% by volume is reached, the oxygen concentration detector emits a warning signal to warn the operator to ventilate the corridor to reduce the content of other gases (including C2H2 / N2, etc.) and increase the oxygen content to ensure the safety of the operator.

[0024] Preferably, the high and low level gauge is a radio frequency admittance type high and low level gauge, which is arranged within a range of 1 m near the feed inlet of the calcium carbide silo; the continuous level gauge is a radar level gauge, which is arranged on the side away from the feed inlet of the calcium carbide silo to avoid the influence of the discharging process on the detection.

[0025] Preferably, the explosion-proof system includes at least six rupture discs, which are installed on the top of the calcium carbide silo, and railings are arranged around the rupture discs. Since the flammable and explosive gases in the calcium carbide silo mostly accumulate at the top of the silo, this layout design can make the gas in the silo move upward to push open the rupture disc when the gas pressure in the calcium carbide silo is too high or other dangerous working conditions occur, which can play the role of timely pressure relief and explosion protection, and can effectively ensure the safety of the calcium carbide silo.

[0026] Preferably, the control system includes a host computer of the computer control system, a data acquisition box connected to the host computer, and a PLC control box. The host computer is configured with an alarm; the data acquisition box is installed in the belt corridor on the top of the calcium carbide silo to collect and display in real time the internal temperature, C2H2 concentration, smoke concentration, oxygen concentration and level height of the calcium carbide silo. After the data acquisition box processes the collected signals, it communicates with the host computer of the computer control system through RS485, and the gas injection device is connected to the PLC control box. In this technical solution, the PLC controller can control the start and stop of each device in the system. After receiving the temperature or C2H2 or O2 alarm command, the controller in the PLC control box automatically triggers the device to work or is manually operated to realize flexible selection of local control or remote control.

[0027] As described above, the present invention has at least the following beneficial effects compared with the prior art:

[0028] 1. The safety protection system of the calcium carbide silo of the present invention combines the structural design of the calcium carbide silo, which can effectively realize the safe and stable operation of the calcium carbide silo, change passive maintenance to active prevention, reduce the operating labor intensity and safety hazards of the staff to the lowest level, and can flexibly select local control or remote control to comprehensively eliminate potential safety threats of the calcium carbide silo, significantly reduce the maintenance cost of the calcium carbide silo, and realize the whole process automation.

[0029] 2. By integrating the designs of the monitoring system, control system, and alarm system, the present invention can effectively and comprehensively collect and real-time display the internal temperature, C2H2 concentration, smoke concentration, oxygen concentration, and material level height signals of the calcium carbide silo, so as to trigger an alarm when the real-time monitoring value reaches the preset threshold, and trigger the action of the nitrogen protection system through the control system, thereby ensuring that when the alarm signal generated by the safety monitoring and control system of the calcium carbide silo is detected, the inerting protection system is automatically activated, ensuring the safe operation of the calcium carbide silo under any storage conditions, and the whole set truly realizes automatic control, effectively enabling unmanned operation.

[0030] 3. The nitrogen protection system of the present invention uses inert gas to dilute and displace the combustible gas and oxygen above the calcium carbide, diluting the concentration of the combustible gas above the calcium carbide silo, providing a theoretical basis for the safety prevention and control of calcium carbide explosion, and having good application prospects in the field of acetylene production technology. With the gradual improvement of the production safety technology of calcium carbide-related enterprises in China, the present invention has quite good application and promotion value in calcium carbide production enterprises.

[0031] In summary, the purpose of the present invention is to provide a safety monitoring and protection system for calcium carbide silos, which can achieve 24-hour real-time monitoring and tracking of the collected data of each sensor on site, the data historical curve, the working state of the equipment, and early warning of the occurrence of accidents, changing passive maintenance to preventive maintenance, being able to alarm in time when a fault occurs, remotely diagnose the faulty equipment, and remotely guide the elimination of potential threats, realizing the whole process automation; at the same time, the protection system has the characteristics of reliable operation, stability, extending the service life of the calcium carbide silo, no pollution discharge, and extremely low operating cost, and has good application prospects in the field of acetylene production technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention will be described by way of specific embodiments with reference to the drawings, where

[0033] Figure 1 is a schematic diagram of the safety protection system for the calcium carbide silo in an embodiment of the present invention;

[0034] Figure 2 is the layout diagram of the top of the calcium carbide silo of the safety protection system for the calcium carbide silo in an embodiment of the present invention;

[0035] Figure 3 is the control electrical schematic diagram of the safety protection system for the calcium carbide silo in an embodiment of the present invention;

[0036] Figure 4 is the process flow diagram of the nitrogen protection system in the safety protection system for the calcium carbide silo in an embodiment of the present invention.

[0037] Description of reference numerals: 1 - Calcium carbide silo; 2 - Temperature sensor; 3 - C2H2 concentration detection sensor; 4 - Smoke detector; 5 - Oxygen probe; 6 - Dust concentration sensor; 7 - Respiratory safety valve; 8 - High and low level gauge; 9 - Explosion-proof film; 10 - Sealing gas pipeline; 11 - Injection gas pipeline; 12 - Relief gas pipeline; 13 - Sealing gas valve; 14 - Injection gas valve; 15 - Relief gas valve; 16 - Nitrogen gas storage tank; 17 - Main pipeline; 18 - Pressure reducing valve; 19 - Belt corridor at the top of the calcium carbide silo; 20 - Inlet of the calcium carbide silo. Detailed implementation manners

[0038] All features disclosed in this specification, or all steps in the disclosed methods or processes, except for mutually exclusive features and / or steps, can be combined in any manner.

[0039] Any feature disclosed in this specification (including any additional claims, abstract) can be replaced by other equivalent or similar-purpose alternative features unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is only an example of a series of equivalent or similar features.

[0040] Embodiment 1

[0041] The embodiment is basically as Figure 1 and Figure 2 shown: This embodiment provides a safety protection system for a calcium carbide silo. Taking a steel calcium carbide silo 1 with a calcium carbide capacity of 1000 tons, a diameter of 10 m and a height of 14 m as an example, its safety protection system includes a temperature detection system, an acetylene C2H2 monitoring system, a smoke monitoring system, an oxygen monitoring system, a dust concentration monitoring system, a pressure protection system, a level monitoring system, an explosion-proof system, a nitrogen protection system and a control system. The control system is configured with an alarm; it can effectively and comprehensively collect and display in real time the internal temperature, C2H2 concentration, smoke concentration, oxygen concentration and level height signals of the calcium carbide silo 1, so as to generate an alarm when the real-time monitoring value reaches a preset threshold, and trigger the nitrogen protection system to act through the control system, so as to ensure that when an alarm signal generated by the safety monitoring and control system of the calcium carbide silo 1 is detected, the inerting protection system is automatically turned on, ensuring the safe operation of the calcium carbide silo 1 under any storage conditions, and the whole set truly realizes automatic control, and can effectively achieve unmanned operation.

[0042] As Figure 3As shown in the figure, the control system provided in this embodiment includes the upper computer of the computer control system, a data acquisition box connected to the upper computer, and a PLC control box. The alarm configured in the control system is connected to the upper computer. The data acquisition box is installed in the top belt corridor 19 of the calcium carbide silo 1 to collect and display in real time the internal temperature, C2H2 concentration, smoke concentration, oxygen concentration, and material level height of the calcium carbide silo 1. The data acquisition box provided in this embodiment contains a digital quantity acquisition module, an intelligent gas acquisition instrument, a switch quantity acquisition module, a power supply module, a communication conversion module, etc. The data acquisition box meets the electrical requirements and has an IP65 protection level, so that after processing the collected signals, the data acquisition box communicates with the upper computer of the computer control system through RS485.

[0043] Specifically, the temperature detection system in the calcium carbide silo 1 provided in this embodiment is used to comprehensively monitor the temperature of calcium carbide at various parts in the calcium carbide silo 1. Since once the acetylene gas generated by calcium carbide burns, it will inevitably cause a sharp rise in the internal temperature of the steel silo. The temperature detection system provided in this embodiment includes at least one temperature sensor 2 installed in the calcium carbide silo 1. The temperature sensor 2 is connected to the data acquisition box of the control system and is used to monitor the temperature change of the calcium carbide inside the silo. As a preference, taking the temperature detection system provided in this embodiment including a set of multi-point temperature measurement cable sensors as an example, the multi-point temperature measurement cable sensors are evenly suspended at the top of the calcium carbide silo 1, so that the multi-point temperature measurement cable sensors extend to the surface of the calcium carbide layer in the calcium carbide silo 1, which can effectively monitor the temperature change of the calcium carbide inside the silo. Moreover, this sensor has the characteristics of being resistant to strong impact, simple to install, easy to plug and maintain, and suitable for high-strength media such as uneven calcium carbide size and irregular shape, and can achieve the effects of temperature measurement point positioning, single-channel alarm, and unified alarm. The data is transmitted to the control system in a timely manner through the data acquisition box, and the monitoring values are displayed and alarmed, and the specific position of the temperature alarm point in the calcium carbide material is judged according to the alarm signal.

[0044] The acetylene C2H2 monitoring system provided in this embodiment includes at least one set of C2H2 concentration detection sensors installed on the top of the calcium carbide silo 1. The C2H2 concentration detection sensors extend downward into the calcium carbide silo 1 through installation accessories and are connected to the control system. Preferably, in this embodiment, taking the acetylene C2H2 monitoring system provided with one set of C2H2 concentration detection sensors as an example, the C2H2 concentration detection sensors are arranged on the top of the calcium carbide silo 1 and extend downward into the calcium carbide silo 1 by at least 1000 mm through installation accessories. There is C2H2 gas concentration online analysis and detection software in the upper computer of the control system. The analysis and detection software specifically adopts the existing technology and is not the invention point of this disclosure, so it will not be elaborated here. It is set that the C2H2 content in the calcium carbide silo 1 during normal operation is <1%. When the detection in the measurement range reaches the preset threshold, an alarm is triggered. When it exceeds 1.25%, the alarm is triggered immediately. The control system prompts the need for monitoring under normal circumstances. When there is a sign of an increase in the C2H2 concentration and the control system of the calcium carbide silo 1 monitors that its C2H2 concentration reaches the preset threshold, the injection valve 14 of the corresponding nitrogen protection system of the calcium carbide silo 1 is immediately triggered to start, increasing the amount of nitrogen injected into the calcium carbide silo 1 until the monitoring value of the acetylene C2H2 monitoring system returns to normal, and the action of the nitrogen protection system is stopped.

[0045] The smoke monitoring system provided in this embodiment includes at least one set of smoke detectors 4 installed on the top of the calcium carbide silo 1. The smoke detectors 4 extend downward into the calcium carbide silo 1 through installation accessories and are connected to the data acquisition box of the control system to collect the smoke information at the top of the calcium carbide silo 1 and transmit the collected information to the data acquisition box. Preferably, in this embodiment, taking the smoke monitoring system provided with one set of smoke detectors 4 as an example, the smoke detectors 4 are arranged on the top of the calcium carbide silo 1 and extend downward into the calcium carbide silo 1 by at least 1000 mm through installation accessories. Since a large amount of thick smoke is inevitably generated once the acetylene generated by calcium carbide starts to burn, in this technical solution, the smoke detectors 4 use a switch quantity acquisition module to collect the smoke signals through the local data acquisition box at the top of the silo and transmit them to the silo control system in a timely manner.

[0046] The oxygen monitoring system provided in this embodiment includes at least one set of oxygen probes 5 installed inside the top of the calcium carbide silo 1. Preferably, this embodiment takes the oxygen monitoring system provided with one set of oxygen probes 5 as an example. The oxygen probe 5 is connected to the data acquisition box of the control system and is used to monitor the oxygen content in the calcium carbide silo 1. The interlock value range of the nitrogen filling and the replacement gas concentration of the space gas is between 1% - 2%. The oxygen concentration threshold is preset in the control system. When the preset value is exceeded, the controller triggers the alarm of the alarm to remind the operator that the oxygen concentration has reached the interlock value, and triggers the corresponding valve action of the protection system of the calcium carbide silo 1 to increase the nitrogen injection amount of the calcium carbide silo 1 until the monitoring value of the oxygen monitoring system returns to normal. Preferably, the oxygen monitoring system provided in this embodiment further includes oxygen concentration detectors installed on the top belt corridor 19 and the bottom belt corridor of the calcium carbide silo 1. The oxygen concentration detectors are connected to the control system. The oxygen concentration detectors in this embodiment are built-in with warning prompts, which are connected to the data acquisition box and have the function of alarming simultaneously on-site and in the control room. So that when the minimum safety content of 20% by volume is reached, the oxygen concentration detector emits a warning signal to remind the operator to ventilate the corridor to reduce the content of other gases (including C2H2 / N2, etc.) and increase the oxygen content to ensure the safety of the operator.

[0047] The dust concentration monitoring system provided in this embodiment includes a dust concentration sensor 6 and a dust collector installed inside the top of the calcium carbide silo 1. The dust concentration sensor and the dust collector are respectively connected to the control system, so that when the dust concentration in the calcium carbide silo 1 exceeds the preset value, the dust collector is triggered to start to dust the inside of the calcium carbide silo 1. This embodiment provides that one dust concentration sensor 6 is configured in each calcium carbide silo 1. When the dust concentration exceeds the preset value, an alarm is triggered so that necessary safety measures can be taken in time, and the top dust collector of the calcium carbide silo 1 is opened to reduce the dust concentration until the safe concentration value, and the alarm is displayed through data acquisition to the computer industrial control system.

[0048] The pressure protection system provided in this embodiment includes a pressure sensor and a breathing safety valve 7 configured in the calcium carbide silo 1. The pressure sensor and the breathing safety valve 7 are respectively connected to the control system, so that when the pressure in the calcium carbide silo 1 exceeds the preset value, the breathing safety valve 7 is triggered to start to reduce the pressure inside the calcium carbide silo 1. This embodiment is set so that when the set maximum pressure of 2 kPa and the minimum of -0.3 kPa are exceeded, the PLC controller triggers the breathing safety valve 7 to start to ensure the safety of the calcium carbide silo 1 body.

[0049] The level monitoring system provided in this embodiment includes a high and low level gauge 8 and a continuous level gauge vertically installed at the top of the calcium carbide silo 1. The high and low level gauge 8 and the continuous level gauge are respectively connected to the control system. Preferably, one radio frequency admittance type high and low level gauge 8 is installed for each calcium carbide silo 1 provided in this embodiment, vertically installed at the top of the silo, set within a range of 1 m near the feed inlet of the calcium carbide silo 1, outputting signals through MODBUS RS485 to the on-site data box to display high level and low level alarms locally, and outputting 4 - 20 mA signals to the PLC system; the signals are collected and displayed on the computer industrial control system to display alarms and record the continuously measured data. Preferably, one radar level gauge is installed for each calcium carbide silo 1 provided in this embodiment, vertically installed at the top of the silo, set on the side away from the feed inlet of the calcium carbide silo 1 by 20, so as to avoid the influence on detection during the discharging process.

[0050] The explosion-proof system provided in this embodiment includes multiple explosion-proof membranes 9 configured on the top of the calcium carbide silo 1. The explosion-proof membranes 9 are connected to the data acquisition box of the control system. Preferably, for a steel calcium carbide silo 1 with a stock of 1000 t, to ensure its explosion-proof safety, the explosion-proof system includes at least six rupture disks. Taking the six rupture disks provided in this embodiment as an example, they are installed on the top of the calcium carbide silo 1, and railings are arranged around the rupture disks. Since a large amount of flammable and explosive gases accumulate at the top of the calcium carbide silo 1, when the gas pressure in the calcium carbide silo 1 is too high or other dangerous working conditions occur, the gas in the silo moves upward to push open the explosion-proof membrane 9, which can achieve the purpose of timely pressure relief and explosion protection, and can effectively ensure the safety of the calcium carbide silo 1.

[0051] Please refer to Figure 1 and Figure 4 As shown, the nitrogen protection system provided in this embodiment includes an injection device and a pre-buried pipe network arranged circumferentially around the calcium carbide silo 1 body. The injection device is connected to the PLC control box of the control system, so that when the above detection parameters reach the preset threshold value and trigger the alarm of the alarm, the injection device is triggered to start and fill nitrogen into the calcium carbide silo 1 through the pre-buried pipe network. Preferably, the pre-buried pipe network includes a sealing pipe network 10 arranged at the lower conical hopper end of the calcium carbide silo 1, an injection pipe network 11 arranged at the cylindrical end of the calcium carbide silo 1 and near the fold line of the conical hopper end, and a gas release pipe network 12 arranged at the cylindrical end of the calcium carbide silo 1 away from the conical hopper end; and a sealing valve 13, an injection valve 14 and a gas release valve 15 connected to the PLC control box are respectively configured on the sealing pipe network 10, the injection pipe network 11 and the gas release pipe network 12. As a further preference, one circle of sealing pipe network 10, two circles of injection pipe network 11 and one circle of gas release pipe network 12 are designed to ensure that nitrogen can penetrate into the material as evenly as possible to the greatest extent and avoid the occurrence of gas channeling; the sealing pipe network 10, the injection pipe network 11 and the gas release pipe network 12 in this embodiment are designed according to the structural characteristics of the calcium carbide silo 1, and this design is safe, reliable, ingenious and reasonable.

[0052] The working principle of the above nitrogen protection system is as follows: design a circle of sealing pipe network 10, which is used to arrange the sealing pipe at the lower cone bucket end of the calcium carbide silo 1 and close to the bottom of the calcium carbide silo 1, and inject inert gas through the gas injection equipment to make the inert gas seal the discharge port, prevent air from penetrating into the calcium carbide layer, that is, isolate the external oxygen, and form a layer of air-locking pipe at the discharge port of the calcium carbide silo 1 to ensure the gas-locking property of the system; design two circles of gas injection pipe network 11, which are used to arrange the gas injection pipe at the cylinder end of the calcium carbide silo 1 and close to the cone. At the fold line at the bucket end, high-purity inert gas can penetrate into the calcium carbide layer to dilute the oxygen concentration around the calcium carbide, and use the gas flow to take away part of the heat, thereby achieving the effect of cooling the calcium carbide; a circle of gas release pipe network 12 is designed to arrange the gas release pipeline at the cylinder end of the calcium carbide silo 1 away from the cone bucket end, so that the inert gas can dilute and replace the combustible gas and oxygen on the top of the calcium carbide, dilute the concentration of combustible gas on the top of the calcium carbide silo 1, dilute the oxygen concentration, prevent explosion, and effectively protect the safety of the calcium carbide silo 1.

[0053] Specifically, the gas injection equipment includes a nitrogen storage tank 16, a main line 17 connected to the nitrogen storage tank 16, and a nitrogen pressure reducing valve 18 arranged on the main line 17. The nitrogen pressure reducing valve 18 is connected to the PLC control box, and the gas sealing network 10, the gas injection network 11 and the gas release network 12 are connected to the main line 17 in sequence from bottom to top.

[0054] It is worth noting that the purity of the nitrogen provided in this embodiment should be ≥95%. The inertness principle of nitrogen is utilized to use high-purity nitrogen (≥95%) as an inert gas source. When the measured parameters such as temperature and combustible gas in the safety monitoring system of the calcium carbide silo 1 exceed the limit alarm, the control system of the calcium carbide silo 1 automatically starts the gas injection equipment to fill nitrogen into the silo to dilute the concentration of combustible and explosive gases in the calcium carbide silo 1. In this way, when the monitoring and protection system alarms, the combustible and explosive gases condensed above the calcium carbide layer inside the calcium carbide silo 1 can be replaced in time to ensure the safety of the calcium carbide silo 1. Moreover, the full set of automatic control systems can be operated unmanned.

[0055] On the other hand, in this embodiment, a gas sealing valve 13, an injection valve 14, and a gas release valve 15 connected to the PLC control box are correspondingly arranged in the gas sealing pipe network 10, the injection pipe network 11, and the gas release pipe network 12. The gas sealing valve 13 is specifically a nitrogen gas sealing electric valve, the injection valve 14 is specifically a nitrogen gas injection electric valve, and the gas release valve 15 is specifically a nitrogen gas release electric valve, which is convenient for automatic control. Through the coordinated design of this part of the pipeline and valves, the inert gas coming out of the nitrogen gas storage tank 16 can be effectively controlled to enter the embedded pipeline network through the calcium carbide silo 1. The inert gas is stored in the main pipeline 17 from bottom to top. According to the detection signal obtained by the control system, the control valves at different elevations close to the main pipeline 17 are automatically triggered to act, so that the high-purity inert gas is filled into this layer. In this way, the gas gradually increases from low to high, replacing the combustible gas above the material. The design of the pressure reducing valve 18 in this embodiment is to reduce the pressure of the pressurized gas so that its pressure value meets the requirements, so that there will be no dust when the inert gas is injected into the calcium carbide silo 1. As described above, when the safety monitoring system of the calcium carbide silo 1 finds an abnormality, the nitrogen protection system of the calcium carbide silo 1 will automatically start the corresponding valve and inject nitrogen into the calcium carbide silo 1 intermittently.

[0056] Thus, the specific implementation manner of the PLC control system is as follows: when the safety monitoring system of the calcium carbide silo 1 finds an abnormality, the silo inerting system automatically starts the control system to trigger the opening of the pressure reducing valve 18 of the nitrogen protection system, and injects nitrogen into the calcium carbide silo 1 intermittently. Therefore, the nitrogen protection system uses the PLC control box to control the start and stop of the whole set of devices. The PLC control box is the core control device of the nitrogen protection system and starts to work since it receives the temperature or C2H2 or O2 alarm command, and automatically or manually starts and executes the following functions:

[0057] 1. Select a preset flow rate set value according to the command partition, and automatically control the gas to be sprayed and stopped at a constant flow rate;

[0058] 2. Control and display the working status of the recording system, and stop working when the nitrogen output meets the storage requirements;

[0059] 3. Send out a local indicator alarm signal to prompt the staff that the system has been started and operated;

[0060] 4. Start the corresponding partition release valve, record and transmit the partition release valve switch signal to the control room remotely;

[0061] 5. Parameters such as flow signal and pressure signal are transmitted through a 4-20mA standard signal;

[0062] 6. The system control mode can be selected as local control or remote control, and the manual control mode is preferred according to requirements;

[0063] 7. Detect faults in parts such as system communication and circuit, and issue an alarm prompt.

[0064] The upper computer of the computer control system is configured with the latest industrial control configuration to realize functions such as realistic picture display, man-machine dialogue, alarm record, accident recall query, report printing, and data curves. The specific implementation principles are all prior arts and are not the invention points of the present disclosure, so they will not be elaborated here.

[0065] In summary, the calcium carbide silo safety protection system provided by the present invention, combined with the structural design of the calcium carbide silo, can effectively achieve the safe and stable operation of the calcium carbide silo, change passive maintenance to active prevention, reduce the labor intensity of staff operation and potential safety hazards to the lowest level, and can be flexibly selected according to local control or remote control, comprehensively eliminate potential safety threats in the calcium carbide silo, significantly reduce the maintenance cost of the calcium carbide silo, and achieve full-process automation; the design of the monitoring system, control system and alarm system of the present invention can effectively and comprehensively collect and display in real time the internal temperature, C2H2 concentration, smoke concentration, oxygen concentration and material level height signals of the calcium carbide silo, so as to trigger an alarm when the real-time monitoring value reaches a preset threshold, and trigger the action of the nitrogen protection system through the control system, so as to ensure that when the alarm signal generated by the safety monitoring and control system of the calcium carbide silo is detected, the inerting protection system is automatically turned on to ensure the safe operation of the calcium carbide silo under any storage conditions, and the whole set truly realizes automatic control, and can effectively achieve unmanned operation. Therefore, the present invention has quite good application and promotion value in enterprises producing calcium carbide and is suitable for popularization and use.

[0066] The present invention is not limited to the foregoing specific embodiments. The present invention extends to any new feature or any new combination disclosed in this specification, as well as any new method or process step or any new combination disclosed.

Claims

1. Calcium carbide silo safety protection system, Characterized in that: It includes a temperature detection system, an acetylene C2H2 monitoring system, a smoke monitoring system, an oxygen monitoring system, a dust concentration monitoring system, a pressure protection system, a material level monitoring system, an explosion protection system, a nitrogen protection system and a control system; The temperature detection system includes a temperature sensor installed inside the calcium carbide silo, and the temperature sensor is connected to the control system for monitoring the temperature change of calcium carbide inside the silo; The acetylene C2H2 monitoring system includes a C2H2 concentration detection sensor installed on the top of the calcium carbide silo. The C2H2 concentration detection sensor extends downward into the calcium carbide silo through an installation accessory and is connected to the control system; The smoke monitoring system includes a smoke detector installed on the top of the calcium carbide silo. The smoke detector extends downward into the calcium carbide silo through an installation accessory and is connected to the control system for collecting smoke information at the top of the calcium carbide silo and transmitting the collected information to the control system; The oxygen monitoring system includes an oxygen probe installed inside the top of the calcium carbide silo, and the oxygen probe is connected to the control system for monitoring the oxygen content inside the calcium carbide silo; The dust concentration monitoring system includes a dust concentration sensor and a dust collector installed inside the top of the calcium carbide silo. The dust concentration sensor and the dust collector are respectively connected to the control system, so that when the dust concentration inside the calcium carbide silo exceeds a preset value, the dust collector is triggered to start to dust the inside of the calcium carbide silo; The pressure protection system includes a pressure sensor and a breathing safety valve configured inside the calcium carbide silo. The pressure sensor and the breathing safety valve are respectively connected to the control system, so that when the pressure inside the calcium carbide silo exceeds a preset value, the breathing safety valve is triggered to start to reduce the pressure inside the calcium carbide silo; The material level monitoring system includes a high and low material level meter and a continuous material level meter vertically installed on the top of the calcium carbide silo. The high and low material level meter and the continuous material level meter are respectively connected to the control system; The explosion protection system includes multiple explosion-proof membranes configured on the top of the calcium carbide silo, and the explosion-proof membranes are connected to the control system; The nitrogen protection system includes an injection device and a pre-buried pipe network arranged circumferentially around the calcium carbide silo body. The injection device is connected to the control system, so that when the detection parameters reach a preset threshold, the injection device is triggered to start and fill nitrogen into the calcium carbide silo through the pre-buried pipe network; The acetylene C2H2 monitoring system includes at least one set of C2H2 concentration detection sensors. The C2H2 concentration detection sensors are arranged on the top of the calcium carbide silo and extend downward into the calcium carbide silo through an installation accessory by at least 1000 mm; The explosion protection system includes at least six bursting discs, which are installed on the top of the calcium carbide silo, and a railing is arranged around the bursting discs.

2. The calcium carbide silo safety protection system according to claim 1, Characterized in that: The embedded pipe network includes an air sealing pipe network arranged at the lower conical hopper end of the calcium carbide silo, an air injection pipe network arranged at the cylindrical end of the calcium carbide silo and near the fold line of the conical hopper end, and an air release pipe network arranged at the cylindrical end of the calcium carbide silo far from the conical hopper end; and an air sealing valve, an air injection valve, and an air release valve connected to the control system are respectively configured in the air sealing pipe network, the air injection pipe network, and the air release pipe network.

3. The calcium carbide silo safety protection system according to claim 2, characterized in that: The air injection device includes a nitrogen gas storage tank, a main pipeline connected to the nitrogen gas storage tank, and a pressure reducing valve configured on the main pipeline. The pressure reducing valve is connected to the control system, and the pipe networks of the air sealing pipe network, the air injection pipe network, and the air release pipe network are communicated with the main pipeline in sequence from bottom to top.

4. The calcium carbide silo safety protection system according to claim 1, characterized in that: The temperature detection system includes at least one set of multi-point temperature measurement cable-type sensors, and the multi-point temperature measurement cable-type sensors are hoisted at the top of the calcium carbide silo so that the multi-point temperature measurement cable-type sensors extend to the surface of the calcium carbide layer in the calcium carbide silo.

5. The calcium carbide silo safety protection system according to claim 1, characterized in that: The smoke monitoring system includes at least one set of smoke detectors, and the smoke detectors are arranged at the top of the calcium carbide silo and extend downward into the calcium carbide silo by at least 1000 mm through installation accessories.

6. The calcium carbide silo safety protection system according to claim 1, characterized in that: The oxygen monitoring system further includes oxygen concentration detectors installed in the top belt corridor and the bottom belt corridor of the calcium carbide silo, and the oxygen concentration detectors are connected to the control system.

7. The calcium carbide silo safety protection system according to claim 1, characterized in that: The high and low level gauge is a radio frequency admittance type high and low level gauge, which is set within a range of 1 m near the feed inlet of the calcium carbide silo; the continuous level gauge is a radar level gauge, which is set on the side far from the feed inlet of the calcium carbide silo.

8. The calcium carbide silo safety protection system according to any one of claims 1-7, characterized in that: The control system includes a host computer of a computer control system, a data acquisition box connected to the host computer, and a PLC control box. The host computer is configured with an alarm; the data acquisition box is installed in the top belt corridor of the calcium carbide silo, collects and displays in real time the internal temperature, C2H2 concentration, smoke concentration, oxygen concentration, and level height of the calcium carbide silo, so that after the signals collected by the data acquisition box are processed, they are communicated with the host computer of the computer control system through RS485, and the air injection device is connected to the PLC control box.

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