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CN-121993804-A - Tail gas treatment system

CN121993804ACN 121993804 ACN121993804 ACN 121993804ACN-121993804-A

Abstract

The invention discloses a tail gas treatment system, which relates to the technical field of petrochemical industry, and comprises a raw gas injection module, a combustion module and a waste heat recovery module, wherein the raw gas injection module comprises a tail gas injection branch, a factory wind branch and a natural gas branch, the tail gas injection branch comprises a compressor and a first regulating valve which are sequentially connected, the factory wind branch is provided with a second regulating valve, the natural gas branch is provided with a third regulating valve, the combustion module comprises a heating part and a heat exchange part, the heating part is connected with the tail gas injection branch, the factory wind branch and the natural gas branch, the heat exchange part can absorb heat generated by the heating part and transmit the heat to a heat absorption medium, and the waste heat recovery module comprises a liquid injection branch, a circulating heating branch and a steam branch. The technical effect of the technical scheme provided by the invention is that the problems of incomplete combustion and insufficient utilization of a large amount of waste heat existing in the operation of the existing combustion furnace are solved, and the purposes of high-efficiency and economic treatment of the nitrogen-containing tail gas are achieved.

Inventors

  • ZHANG FAWANG
  • TANG YUHAO
  • ZHOU JUN
  • CAI SHAOYONG
  • ZENG FEIPENG
  • LI SHENGLI
  • LI HUITAO
  • REN GANG
  • WANG HONGQUAN
  • WANG ZONGHAI
  • YU JUN

Assignees

  • 中国石油天然气股份有限公司
  • 广东石化有限责任公司

Dates

Publication Date
20260508
Application Date
20250206

Claims (10)

  1. 1. An exhaust gas treatment system for treating storage tank exhaust gas, comprising: The system comprises a raw material gas injection module (1), wherein the raw material gas injection module (1) comprises a tail gas injection branch (a), a plant wind branch (b) and a natural gas branch (c), the tail gas injection branch (a) comprises a compressor (11) and a first regulating valve (12) which are sequentially connected, the plant wind branch (b) is provided with a second regulating valve (13), and the natural gas branch (c) is provided with a third regulating valve (14); The combustion module (2), the combustion module (2) comprises a heating part (21) and a heat exchange part (22), the heating part (21) is connected with the tail gas injection branch (a), the factory wind branch (b) and the natural gas branch (c), the heat exchange part (22) can absorb heat generated by the heating part (21) and transfer the heat to a heat absorption medium, and The heat recovery module (3), the heat recovery module (3) comprises a liquid injection branch (d), a circulation heating branch (e) and a steam branch (f), wherein the liquid injection branch (d) is provided with a fourth regulating valve (31), the liquid injection branch (d) is used for injecting a heat absorption medium into the heat exchange part (22), the circulation heating branch (e) is used for reheating the heated heat absorption medium, and the steam branch (f) is used for guiding the vaporized heat absorption medium to a steam pipe network.
  2. 2. The exhaust gas treatment system according to claim 1, characterized in that the waste heat recovery module (3) comprises a gas-liquid separation tank (32), the gas-liquid separation tank (32) being in communication with the outlet of the liquid injection branch (d), the inlet and outlet of the circulation heating branch (e) and the outlet of the steam branch (f).
  3. 3. The exhaust gas treatment system according to claim 2, characterized in that the waste heat recovery module (3) is provided with a liquid level meter (33), the liquid level meter (33) being used for monitoring the liquid level in the gas-liquid separation tank (32), the liquid level meter (33) being electrically connected with the fourth regulating valve (31).
  4. 4. The exhaust gas treatment system according to claim 2, characterized in that the steam branch (f) is provided with a temperature and pressure reducer (34), the waste heat recovery module (3) is provided with a steam conditioning branch (g) communicating the inlet of the liquid injection branch (d) with the temperature and pressure reducer (34), the steam conditioning branch (g) being provided with a fifth regulating valve (35).
  5. 5. The exhaust gas treatment system according to claim 4, wherein the steam branch (f) is provided with a first temperature sensor (36) on the path of the steam pipe network, the first temperature sensor (36) being electrically connected to the fifth regulating valve (35).
  6. 6. The exhaust gas treatment system according to any one of claims 1 to 5, characterized in that the heat exchanging portion (22) is provided with a second temperature sensor (23), the second temperature sensor (23) being electrically connected to the first regulating valve (12) and the third regulating valve (14).
  7. 7. The exhaust gas treatment system according to any one of claims 1 to 5, characterized in that the combustion module (2) is further provided with a sensor assembly (24), the sensor assembly (24) being electrically connected to the second regulating valve (13).
  8. 8. The exhaust treatment system of claim 7, wherein the sensor assembly (24) includes a VOCs sensor (241), a third temperature sensor (242), and an oxygen concentration sensor (243).
  9. 9. The exhaust gas treatment system according to any one of claims 1 to 5, characterized in that a heat exchange tube (25) is provided in the heat exchange portion (22), the heat exchange tube (25) being of a spiral design.
  10. 10. The exhaust gas treatment system according to claim 9, characterized in that a plurality of heat exchange tubes (25) are provided in the heat exchange portion (22), at least one of the heat exchange tubes (25) being of a spiral design.

Description

Tail gas treatment system Technical Field The invention relates to the technical field of petrochemical industry, in particular to a tail gas treatment system. Background In petrochemical storage and transportation tank areas, storage tanks are one of the most common devices, and have the characteristics of large occupied area, large number of storage tanks, various types of stored materials and the like. The constant-pressure fixed top tank has the largest quantity in the storage tank, the types of the storage tank comprise an inner floating disc tank, a vault tank and the like, and the storage tank is the biggest unorganized emission source of atmospheric pollutants for enterprises and is also an important safety management and control area for the enterprises. Based on the storage tank area intrinsic safety management concept, petrochemical enterprises seal nitrogen on the atmospheric storage tanks capable of implementing nitrogen protection, and the gas phase space oxygen concentration in the atmospheric storage tanks is controlled within the range of not more than 5%, so that explosion conditions are eliminated, and storage tank explosion accidents are avoided. The tail gas components discharged from the oil tank area mainly comprise nitrogen, hydrocarbons, benzene series, sulfides, water vapor, air and the like. The tail end treatment of the polluted nitrogen discharged by the conventional petrochemical enterprise storage and transportation tank areas is mostly treated by adopting a combustion method so as to realize the up-to-standard discharge. However, the operation condition of the combustion furnace is difficult to realize automatic adjustment, and is easy to cause incomplete tail gas combustion to generate VOCs (Volatile Organic Compounds ) gas polluting the environment. In addition, conventional burners do not utilize the waste heat of combustion, resulting in significant heat losses. Disclosure of Invention The invention mainly aims to provide an oil tank field tail gas treatment system, which aims to solve the problems of incomplete combustion and insufficient utilization of a large amount of waste heat in the operation of the existing combustion furnace and achieve the aims of high-efficiency and economic treatment of nitrogen-containing tail gas. The tail gas treatment system comprises a raw gas injection module, a combustion module and a waste heat recovery module, wherein the raw gas injection module comprises a tail gas injection branch, a factory wind branch and a natural gas branch, the tail gas injection branch comprises a compressor and a first regulating valve which are sequentially connected, the factory wind branch is provided with a second regulating valve, the natural gas branch is provided with a third regulating valve, the combustion module comprises a heating part and a heat exchange part, the heating part is connected with the tail gas injection branch, the factory wind branch and the natural gas branch, the heat exchange part can absorb heat generated by the heating part and transmit the heat to a heat absorbing medium, the waste heat recovery module comprises a liquid injection branch, a circulating heating branch and a steam branch, the liquid injection branch is provided with a fourth regulating valve, the liquid injection branch is used for injecting the heat exchange part with the heat absorbing medium, the circulating heating branch is used for reheating the heated heat absorbing medium, and the steam branch is used for guiding the gasified heat absorbing medium to a steam pipe network. In one embodiment, the waste heat recovery module comprises a gas-liquid separation tank communicating with the outlet of the liquid injection branch, the inlet and outlet of the circulation heating branch, and the outlet of the vapor branch. In an embodiment, the waste heat recovery module is provided with a liquid level meter, the liquid level meter is used for monitoring the liquid level height in the gas-liquid separation tank, and the liquid level meter is electrically connected with the fourth regulating valve. In an embodiment, the steam branch is provided with a temperature and pressure reducer, the waste heat recovery module is provided with a steam adjusting branch, the steam adjusting branch is communicated with the inlet of the liquid injection branch and the temperature and pressure reducer, and the steam adjusting branch is provided with a fifth adjusting valve. In one embodiment, the steam branch is provided with a first temperature sensor on a passage of the steam pipe network, and the first temperature sensor is electrically connected with the fifth regulating valve. In one embodiment, the heat exchanging part is provided with a second temperature sensor, and the second temperature sensor is electrically connected with the first regulating valve and the third regulating valve. In one embodiment, the combustion module is further provided with a sensor assembly electrica