An intelligent flare emission and recovery system
Through the intelligent torch emission and recycling system, the torch gas combustion is monitored and optimized in real time, and the torch gas emission problems in petrochemical plants and refineries are solved, achieving efficient combustion and high recovery rates, and meeting environmental protection requirements.
Patent Information
- Application Number
- CN202210126825.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-02-11
- Publication Date
- 2025-08-15
- Estimated Expiration
- 2042-02-11
AI Technical Summary
The torch gas emission systems of existing petrochemical plants and refineries cannot be effectively supervised, which makes it difficult for the torch gas combustion efficiency and cracking rate to meet environmental protection requirements, especially when the equipment is started, shut down or equipment failure, resulting in excessive VOCs gas emissions.
The intelligent torch emission and recycling system is adopted, and the torch gas condition is monitored in real time through online detection instruments and intelligent control systems. The controllable combustion and efficient recycling of torch gas are achieved through water sealing tanks and smoke-removing steam pipelines. The multi-loop optimization control system is used to improve combustion efficiency and recovery rate.
In normal production and emergency situations, it can effectively control torch gas emissions, improve combustion efficiency and recovery rate, reduce VOCs emissions, realize comprehensive monitoring and management of torch gas, and achieve environmentally friendly combustion efficiency and recovery rate.
Smart Images
Figure CN114659125B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of petrochemical industry and oil refining, and in particular to an intelligent flare emission and recovery system. Background Art
[0002] Currently, petrochemical plants and refineries all utilize flare systems, flare gas holders, and compressor recovery systems. However, these devices and systems are manually operated through a DCS (distributed control system) system, so flares continue to burn during normal production, particularly during plant startup, shutdown, and equipment failures. These flare gas emissions are VOCs. According to a US EPA (Environmental Protection Commission) survey of 500 flare emissions, flare gas emissions from petrochemical and refinery plants account for 61% of total VOC emissions. Currently, there is no regulatory oversight of flare systems, despite the EPA (Environmental Protection Commission) requiring a DRE (Destruction Rate) of at least 98% and a flare combustion efficiency (CE) of at least 98%. Furthermore, China's Ministry of Environmental Protection issued GB31570-2015, "Petroleum Refining Industry Pollutant Emission Standard," in 2015, requiring a DRE of ≥97% for non-methane hydrocarbons (including flare gas) in petrochemical and refinery plants and requiring improved flare combustion efficiency. The gas components emitted by flare gas vary greatly and are changing all the time. The flare burns at high altitudes and cannot be supervised, which is impossible with current operating technology. Summary of the Invention
[0003] The purpose of the present invention is to provide an intelligent system for flare emission and recovery to solve the problems mentioned in the background technology. In order to achieve the above purpose, the present invention provides the following technical solutions: an intelligent system for flare emission and recovery, comprising a high-pressure flare gas main pipe and a low-pressure flare gas main pipe, said high-pressure flare gas main pipe and low-pressure flare gas main pipe are both installed with main pipe detection instruments, said high-pressure flare gas main pipe and low-pressure flare gas main pipe are connected to the flare gas recovery system through a pipeline, said high-pressure flare gas main pipe and low-pressure flare gas main pipe are connected to the detection pipeline at the outlet, said detection pipeline is installed with an online flare gas calorific value analyzer, an online flare gas analyzer, an online flare gas main pipe temperature meter, an online flare gas main pipe pressure meter and an online flare gas main pipe flow meter, said online flare gas calorific value ... The analyzer, online flare gas main pipe temperature meter, online flare gas main pipe pressure meter and online flare gas main pipe flow meter are connected to the flare gas combustion feedforward plus multi-loop optimization control intelligent system by telecommunication. The detection pipeline is connected to the water seal tank, the water seal tank pipeline is connected to the torch, the flare is equipped with a long-burning lamp ignition device, the flare is connected to the smoke suppression steam pipe, and there are three smoke suppression steam pipes, namely, the induced smoke suppression steam pipe, the central smoke suppression steam pipe and the top smoke suppression steam pipe. Steam flow meters and steam control valves are installed on the three smoke suppression steam pipes, and the steam flow meters and steam control valves are connected to the flare gas combustion feedforward plus multi-loop optimization control intelligent system by telecommunication.
[0004] Preferably, the flare gas recovery system includes a flare gas recovery branch, and three flare gas recovery branches are provided. The three flare gas recovery branches are connected to the cooling system. The flare gas recovery branch includes a high-pressure flare gas recovery pipeline and a low-pressure flare gas recovery pipeline. The high-pressure flare gas recovery pipeline and the low-pressure flare gas recovery pipeline are respectively connected to the high-pressure flare gas main and the low-pressure flare gas main. The high-pressure flare gas recovery pipeline and the low-pressure flare gas recovery pipeline are both installed with a two-way flow meter and a flow control and shut-off valve. The high-pressure flare gas recovery pipeline and the low-pressure flare gas recovery pipeline are connected to a two-way flowmeter I and a temperature transmitter. The temperature transmitter is connected to a water seal tank I, and the water seal tank I is connected to a gas holder. A water seal liquid level transmitter is installed on the water seal tank I, and the water seal liquid level transmitter is connected to a water supply control valve. The water supply control valve is installed on the water inlet pipe of the water seal tank I, and a water outlet control valve is installed on the water outlet pipe of the water seal tank I. The water outlet control valve is connected to the water seal liquid level transmitter, and the gas holder pipeline is connected to the cooling system.
[0005] Preferably, the gas cabinet is equipped with a pressure transmitter, a temperature transmitter, a gas cabinet piston height transmitter and a gas cabinet outlet regulating shut-off valve.
[0006] Preferably, there are two cooling systems, each of which includes a control valve. Two control valves are connected in parallel. The control valve pipeline is connected to the liquid ring compressor, the liquid ring compressor is connected to the cooler, and the cooler is connected to the same buffer tank. The buffer tank is connected to the fuel gas pipeline network through a pipeline.
[0007] Preferably, the main pipe detection instruments include a flare gas main pipe flow meter, a flare gas main pipe pressure gauge, a flare gas main pipe temperature meter, a flare gas main pipe analyzer and a flare gas main pipe calorific value analyzer.
[0008] The technical effects and advantages of the present invention are as follows: Under normal circumstances, the flare gas of this system enters the gas cabinet, including when it is started, shut down, or when there is equipment failure. If the factory loses power or water, the gas cabinet will be overloaded and will enter the flare system for combustion and emission. At the same time, the gas cabinet recovery and flare gas emission are carried out simultaneously. The emission of flare gas is greatly reduced, the recovery rate of flare gas is increased, and economic efficiency is improved. The emission of flare gas can be fully monitored and managed. Flare gas is not emitted during normal production and emergency emissions, and flare emissions are kept within a controllable range, thus realizing the comprehensive management of flare gas in petrochemical plants and refineries and the control of volatile organic compounds (flare gas) VOCs. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 It is a connection diagram of the present invention;
[0010] Figure 2 This is a connection diagram of the flare gas combustion feedforward plus multi-loop optimization control intelligent system of the present invention.
[0011] In order to make the technical means for realizing the present invention, the creative features, the purpose and the effect easily understood, the present invention is further explained below with reference to specific diagrams. In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, an integral connection or a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be internal communication between two components. Example
[0012] like Figure 1 and Figure 2The flare gas emission and recovery intelligent system shown in the figure includes a high-pressure flare gas main pipe 1 and a low-pressure flare gas main pipe 2, and the high-pressure flare gas main pipe 1 and the low-pressure flare gas main pipe 2 are both equipped with a flare gas main pipe flow meter 39, a flare gas main pipe pressure gauge 40, a flare gas main pipe temperature meter 41, a flare gas main pipe analyzer 42 and a flare gas main pipe calorific value analyzer 43. The high-pressure flare gas main pipe 1 and the low-pressure flare gas main pipe 2 are connected to the flare gas recovery system through a pipeline, and the outlets of the high-pressure flare gas main pipe 1 and the low-pressure flare gas main pipe 2 are connected to a detection pipeline 3, and the detection pipeline 3 is equipped with an online flare gas calorific value analyzer 4, an online flare gas analyzer 5, an online flare gas main pipe temperature meter 6, an online flare gas main pipe pressure meter 7 and an online flare gas main pipe flow meter 34, and the online flare gas calorific value analyzer The analyzer 4, the online flare gas analyzer 5, the online flare gas main pipe temperature meter 6 and the online flare gas main pipe pressure meter 7, and the online flare gas main pipe flow meter 34 are connected to the flare gas combustion feedforward plus multi-loop optimization control intelligent system 8 by telecommunication, the detection pipeline 3 is connected to the water seal tank 9, the water seal tank 9 pipeline is connected to the torch 10, the flare 10 is equipped with a long-burning lamp ignition device 11, the flare 10 is connected to the smoke suppression steam pipe, and the smoke suppression steam pipe is provided with three, namely, the induced smoke suppression steam pipe 12, the central smoke suppression steam pipe 13 and the top smoke suppression steam pipe 14, the three smoke suppression steam pipes are equipped with a steam flow meter 15 and a steam control valve 16, the steam flow meter 15 and the steam control valve 16 are connected to the flare gas combustion feedforward plus multi-loop optimization control intelligent system 8 by telecommunication;
[0013] The flare gas recovery system includes a flare gas recovery branch, and there are three flare gas recovery branches. The three flare gas recovery branches are connected to the cooling system. The flare gas recovery branch includes a high-pressure flare gas recovery pipeline 17 and a low-pressure flare gas recovery pipeline 18. The high-pressure flare gas recovery pipeline 17 and the low-pressure flare gas recovery pipeline 18 are respectively connected to the high-pressure flare gas main 1 and the low-pressure flare gas main 2. The high-pressure flare gas recovery pipeline 17 and the low-pressure flare gas recovery pipeline 18 are both installed with a two-way flow meter 19 and a flow control and shut-off valve 20. The high-pressure flare gas recovery pipeline 17 and the low-pressure flare gas recovery pipeline 18 are connected to a two-way flow meter Ⅰ 21 and a temperature variable The transmitter 22 is connected to the water seal tank I 23, and the water seal tank I 23 is connected to the gas cabinet 24. The water seal tank I 23 is equipped with a water seal level transmitter 25, and the water seal level transmitter 25 is connected to the water supply control valve 26. The water supply control valve 26 is installed on the water inlet pipe 27 of the water seal tank I 23, and the water outlet control valve 29 is installed on the water outlet pipe 28 of the water seal tank I 23. The water outlet control valve 29 is connected to the water seal level transmitter 25. The gas cabinet 24 is equipped with a pressure transmitter 30, a temperature transmitter 31, a gas cabinet piston height transmitter 32 and a gas cabinet outlet regulating shut-off valve 33. The pipeline of the gas cabinet 24 is connected to the cooling system;
[0014] The cooling system is provided with two, and the cooling system includes a control valve 35. The control valve 35 is provided with two and connected in parallel. The control valve 35 is connected to the liquid ring compressor 36 through a pipeline, and the liquid ring compressor 36 is connected to the cooler 37. The cooler 37 is connected to the same buffer tank 38, and the buffer tank 38 is connected to the fuel gas pipeline network through a pipeline.
[0015] The process flow and working principle of the present invention are as follows: the system detects the conditions of the flare gas in the high-pressure flare gas main 1 and the low-pressure flare gas main 2 through the flare gas main flow meter 39, the flare gas main pressure gauge 40, the flare gas main temperature meter 41, the flare gas main analyzer 42 and the flare gas main calorific value analyzer 43, and enters the conditions into the computer I / 0 card of the flare emission and intelligent system. Under normal circumstances, when the flare gas fully enters the gas cabinet 10, the system adopts multiple gas cabinets 10 to control the gas cabinet 10 in stages, and installs a water seal tank Ⅰ 23 at the inlet of each gas cabinet 10, and calculates according to the emission of different devices (high-pressure flare pipe network and low-pressure flare pipe network); controls the water seal liquid level height of the water seal tank Ⅰ 23 of the multiple gas cabinets 10 to achieve gas cabinet 10 recovery, selects series recovery and parallel recovery according to the optimization management requirements, and performs feedforward optimization control. At the same time, in order to prevent high To prevent the crosstalk between high-pressure and low-pressure flare gases, a two-way flow meter 19 and a flow control and shut-off valve 20 are installed in the high-pressure flare gas recovery pipeline 17 and the low-pressure flare gas recovery pipeline 18 respectively, and the flow is optimized and controlled by a computer. At the same time, the height of the gas cabinet 10, the speed of the gas cabinet's rise or fall, and the rate of change of the gas cabinet's height are calculated, and the time for the gas cabinet 10 to reach the full height (or the top), the storage space, the number of operating units, the recovery volume and other parameters are calculated and optimized and controlled. The calculation results are safety interlocked with the pressure and temperature parameters measured by the pressure transmitter 30 and the temperature transmitter 31 of the flare gas entering the gas cabinet 10. Once the limit is exceeded, an alarm will be automatically issued. If the limit is still exceeded after the alarm, a safety interlock will be issued to ensure safety, and the flow control and shut-off valve 20 of the gas cabinet 10 will be automatically closed, and the gas cabinet outlet regulating shut-off valve 33 will be opened to cool the flare gas.
[0016] When the factory has a power outage or water outage and the gas cabinet is overloaded, the flare gas is transported to the flare 10 through the high-pressure flare gas main 1 and the low-pressure flare gas main 2. The flare gas combustion feedforward plus multi-loop optimization control intelligent system 8 detects the flow, average molecular weight, pressure and temperature of the flare gas entering the flare 10 through the online flare gas calorific value analyzer 4, the online flare gas analyzer 5, the online flare gas main flow meter 34, the online flare gas main temperature meter 6 and the online flare gas main pressure meter 7. The flare gas flow and average molecular weight are used as feedforward quantities. By controlling the shutoff and conduction of the induced smoke suppression steam pipe 12, the central smoke suppression steam pipe 13 and the top smoke suppression steam pipe 14, the flare gas flow, average molecular weight and the pressure and flow of the smoke suppression steam are optimized to calculate the flare gas combustion rate, and the correct smoke suppression steam is obtained, so that the flare head achieves smokeless combustion and the combustion efficiency CE of the flare is above 98%.
[0017] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. An intelligent flare discharge and recovery system, comprising a high-pressure flare gas main and a low-pressure flare gas main, characterized in that: The high-pressure flare gas main pipe and the low-pressure flare gas main pipe are both equipped with main pipe detection instruments. The high-pressure flare gas main pipe and the low-pressure flare gas main pipe are connected to the flare gas recovery system through pipelines. The outlets of the high-pressure flare gas main pipe and the low-pressure flare gas main pipe are connected to the detection pipeline. The detection pipeline is equipped with an online flare gas calorific value analyzer, an online flare gas analyzer, an online flare gas main pipe temperature meter, an online flare gas main pipe pressure meter and an online flare gas main pipe flow meter. The online flare gas calorific value analyzer, the online flare gas analyzer, the online flare gas main pipe The temperature meter, the online flare gas main pressure meter and the online flare gas main flow meter are connected to the flare gas combustion feedforward plus multi-loop optimization control intelligent system by telecommunication. The detection pipeline is connected to the water seal tank, the water seal tank pipeline is connected to the torch, the torch is equipped with a long-burning lamp ignition device, the torch is connected to the smoke suppression steam pipeline, and there are three smoke suppression steam pipelines, namely the induced smoke suppression steam pipeline, the central smoke suppression steam pipeline and the top smoke suppression steam pipeline. The three smoke suppression steam pipelines are equipped with steam flow meters and steam control valves. The steam flow meters and The steam control valve is connected to the flare gas combustion feedforward plus multi-loop optimization control intelligent system. The flare gas recovery system includes a flare gas recovery branch. There are three flare gas recovery branches. The three flare gas recovery branches are connected to the cooling system. The flare gas recovery branch includes a high-pressure flare gas recovery pipeline and a low-pressure flare gas recovery pipeline. The high-pressure flare gas recovery pipeline and the low-pressure flare gas recovery pipeline are respectively connected to the high-pressure flare gas main and the low-pressure flare gas main. The high-pressure flare gas recovery pipeline and the low-pressure flare gas recovery pipeline are both installed with two-way Flow meter and flow control and shut-off valve, the high-pressure flare gas recovery pipeline and the low-pressure flare gas recovery pipeline are connected to a two-way flow meter I and a temperature transmitter, the temperature transmitter is connected to a water seal tank I, the water seal tank I is connected to a gas holder, a water seal liquid level transmitter is installed on the water seal tank I, the water seal liquid level transmitter is connected to a water supply control valve, the water supply control valve is installed on the water inlet pipe of the water seal tank I, a water outlet control valve is installed on the water outlet pipe of the water seal tank I, the water outlet control valve is connected to a water seal liquid level transmitter, and the gas holder pipeline is connected to a cooling system.
2. The intelligent flare discharge and recovery system according to claim 1, characterized in that: The gas cabinet is equipped with a pressure transmitter, a temperature transmitter, a gas cabinet piston height transmitter and a gas cabinet outlet regulating shut-off valve.
3. The intelligent flare discharge and recovery system according to claim 1, characterized in that: The cooling system is provided with two, and the cooling system includes a control valve. The control valve is provided with two and connected in parallel. The control valve pipeline is connected to the liquid ring compressor, the liquid ring compressor is connected to the cooler, and the cooler is connected to the same buffer tank. The buffer tank is connected to the fuel gas pipeline network through a pipeline.
4. The intelligent flare discharge and recovery system according to claim 1, characterized in that: The main pipe detection instruments include a flare gas main pipe flow meter, a flare gas main pipe pressure gauge, a flare gas main pipe temperature meter, a flare gas main pipe analyzer and a flare gas main pipe calorific value analyzer.
Citation Information
Patent Citations
FCS torch monitoring and management system
CN103335319A
Torch interface safety device skid-mounted FSU
CN113819471A
Torch gas compressor control system
CN207990204U