CN-122009692-A - Storage tank oil gas inhibition recovery device and method based on radiation refrigeration and multistage cold trap

CN122009692ACN 122009692 ACN122009692 ACN 122009692ACN-122009692-A

Abstract

The invention relates to a storage tank oil gas inhibition recovery device and method based on radiation refrigeration and a multistage cold trap, and belongs to the technical field of oil gas storage and transportation, energy conservation and environmental protection. The device is arranged at the exhaust end of the storage tank breather valve and comprises an adiabatic gas collection cavity, a radiation refrigeration condensation module, a backflow liquid guide mechanism and a source pre-cooling inhibition loop. The outer surface of the radiation refrigeration condensation module is provided with a spectrum selective radiation refrigeration layer, the inner surface of the radiation refrigeration condensation module is provided with a condensation fin, and the condensation fin is provided with a macroscopic turbulence unit and a microscopic liquid guide channel which are used for prolonging the retention time of oil gas, destroying a thermal boundary layer and accelerating the self-driving of condensate. The source suppresses the precooling loop and utilizes natural heat convection to introduce tank top gas into the heat-insulating gas collection cavity for precooling and then flows back in the initial stage of temperature rise of the storage tank, and respiratory emission is reduced from the source. The invention has the advantages of zero energy consumption operation in the whole process, double functions of source inhibition and high-efficiency recovery, and provides a safe and economic solution for the treatment of the VOCs of the distributed storage tanks.

Inventors

ZHONG JINQIN
CHEN JIANHENG
ZHANG YELIN
LV YULING
LUO XIAOMING
SHI WENCHAO

Assignees

中国石油大学(华东)

Dates

Publication Date: 20260512
Application Date: 20260325

Claims (10)

1. Storage tank oil gas inhibition recovery unit based on radiation refrigeration and multistage cold trap, characterized by comprising: The bottom of the heat-insulating gas collection cavity (1) is provided with a gas inlet interface (11) and a liquid outlet (12), and the gas inlet interface (11) is used for communicating with a storage tank breather valve; The radiation refrigeration condensation module (2) is covered at the top opening of the heat insulation gas collection cavity (1) and is used for condensing the oil-gas mixture entering the heat insulation gas collection cavity (1) by utilizing a passive radiation refrigeration mode; a backflow liquid guide mechanism (3) communicated with the liquid discharge port (12) and used for guiding the liquid formed by condensation into the storage tank in a single direction, and And the source inhibition precooling loop (6) is communicated with the heat-insulating gas-collecting cavity (1) and the top gas-phase space of the storage tank, and is used for introducing gas in the storage tank into the heat-insulating gas-collecting cavity (1) by utilizing natural heat convection to precool and reflux the gas to the storage tank before the breather valve of the storage tank is opened.
2. The storage tank oil gas inhibition and recovery device based on radiation refrigeration and multistage cold traps according to claim 1, wherein the radiation refrigeration condensation module (2) comprises a high heat conduction substrate (21), the high heat conduction substrate (21) is provided with a side facing to the outside sky and a side facing to the inside of the heat insulation gas collection cavity (1), the side of the high heat conduction substrate (21) facing to the sky is provided with a spectrum selective radiation refrigeration layer (22) and is further provided with a spectrum selective radiation refrigeration layer (22) for radiating heat to space, the side of the high heat conduction substrate (21) facing to the inside of the heat insulation gas collection cavity is extended with a plurality of condensation fins (23), the condensation fins (23) are used for carrying out heat exchange with oil gas in the cavity, the condensation fins (23) are provided with condensation components, the condensation components are macro turbulence units and micro turbulence guide channels, the macro turbulence units are used for prolonging the time on the cold surface and inducing turbulence of gas so as to destroy the gas thermal boundary layer, and the micro turbulence channels are used for accelerating the self-driving of condensation liquid drops through capillary action and gravity cooperative guidance so as to realize update of the condensation surface.
3. The storage tank oil gas suppression and recovery device based on radiation refrigeration and multistage cold trap according to claim 2, wherein the macroscopic turbulence unit comprises shutter slits or stamping flow guide baffles which are staggered on the surface of the condensing fins (23), and the stamping flow guide baffles on the adjacent fins are staggered and are used for enabling an oil gas mixture flowing through to form an S-shaped or spiral turbulent flow field.
4. The storage tank oil gas inhibition and recovery device based on radiation refrigeration and multistage cold trap according to claim 2, wherein the microscopic liquid guide channel comprises a micron-sized groove array extending along the gravity direction on the surface of a fin substrate, the groove array and the surface of the fin are covered with super-oleophobic micro-nano composite coating, and the contact angle of the super-oleophobic micro-nano composite coating to alkane liquid with surface tension of more than 20mN/m is more than 150 degrees, and the rolling angle is less than 10 degrees.
5. The storage tank oil gas inhibition recovery device based on the radiation refrigeration and the multistage cold trap according to claim 1 is characterized in that the source inhibition precooling loop (6) comprises a rising air pipe (61) and a descending liquid gas mixing pipe (62), one end of the rising air pipe (61) is connected to the highest position of the top of the storage tank and communicated with the storage tank, the other end of the rising air pipe is communicated with the upper portion of the heat insulation gas collection cavity (1), one end of the descending liquid gas mixing pipe (62) is communicated with the bottom liquid collection area of the heat insulation gas collection cavity (1), the other end of the descending liquid gas mixing pipe extends into the storage tank, under the heat convection condition, gas at the top of the storage tank enters the heat insulation gas collection cavity (1) through the rising air pipe (61), and condensate carried after cooling flows back to the storage tank through the descending liquid gas mixing pipe (62) to form a heat siphon type natural convection circulation.
6. The storage tank oil gas inhibition recovery device based on radiation refrigeration and multistage cold trap according to claim 5, wherein a pressure difference balance valve (63) is arranged on a rising air pipe (61) of a source inhibition precooling loop (6), when the pressure in the storage tank is lower than a set pressure for opening a breather valve and a thermal convection condition exists, the pressure difference balance valve (63) is in a normally open state, so that gas at the top of the storage tank enters the heat insulation gas collection cavity (1) through the rising air pipe (61) to precool and reflux, when the pressure in the storage tank reaches the set pressure of the breather valve, the pressure difference balance valve (63) is closed, and the waste gas in the storage tank enters the heat insulation gas collection cavity (1) through the gas inlet interface (11) to concentrated condensation.
7. Storage tank oil gas suppression recovery device based on radiation refrigeration and multistage cold trap according to claim 1, further comprising a thermal diode assembly (5), wherein the thermal diode assembly (5) is embedded at the junction of the radiation refrigeration condensation module (2) and the heat insulation gas collection cavity (1) and is used for only allowing unidirectional conduction of heat from the heat insulation gas collection cavity (1) to the radiation refrigeration condensation module (2).
8. The storage tank oil gas inhibition recovery device based on radiation refrigeration and multistage cold traps according to claim 1 is characterized in that the radiation refrigeration condensation module (2) is integrally arranged in an inverted cone shape or a funnel shape, condensation fins (23) are radially distributed along a conical surface, the bottoms of the fins incline to the center of the heat insulation gas collection cavity (1), the backflow liquid guide mechanism (3) comprises a liquid collection funnel (31) and a U-shaped liquid seal pipe (32), the liquid collection funnel (31) is arranged at the liquid discharge port (12), the U-shaped liquid seal pipe (32) is communicated with the bottom of the liquid collection funnel (31), a safety bypass valve (4) is further arranged on the side wall of the heat insulation gas collection cavity (1), and the opening pressure set value of the safety bypass valve (4) is higher than the opening pressure of a storage tank breathing valve.
9. Storage tank oil and gas rejection recovery device based on radiation refrigeration and multistage cold trap according to claim 1, characterized in that the solar reflectance of the spectrally selective radiation refrigeration layer (22) is greater than 0.95 in the 0.3-2.5 μm band and the thermal reflectance in the 8-13 μm band is greater than 0.90.
10. A recovery method of a storage tank oil and gas suppressing recovery apparatus based on radiant refrigeration and multistage cold trap according to any one of claims 1 to 9, characterized by comprising the steps of: The method comprises a source inhibition step, a concentrated condensation recovery step and a liquid-liquid separation step, wherein when the pressure in a storage tank is lower than the opening set pressure of a breather valve and a thermal convection condition exists, a differential pressure balance valve (63) is opened, gas in a gas phase space at the top of the storage tank enters the upper part of an adiabatic gas collection cavity (1) through a rising pipe (61) under the action of natural thermal convection, heat exchange is carried out between the gas and a radiation refrigeration condensation module (2), the density of the cooled gas is increased, a carried part of condensate flows back to the storage tank through a falling liquid gas mixed flow pipe (62) to form a thermosiphon natural convection circulation, so as to inhibit the pressure in the storage tank, the concentrated condensation recovery step is carried out, when the pressure in the storage tank reaches the opening set pressure of the breather valve, the differential pressure balance valve (63) is closed, the breather valve of the storage tank is opened, the gas-liquid mixed gas discharged from the storage tank enters the adiabatic gas collection cavity (1) through an air inlet interface (11), the gas-mixed gas is cooled on the surface of a condensation fin (23) of the radiation refrigeration condensation module (2), the condensable components are condensed into liquid, the condensate is guided back to the storage tank through a reflux liquid guide mechanism (3) in one way, and the condensate liquid in the concentrated condensation recovery step is subjected to form a turbulent flow through the condensation liquid guide unit, and the turbulent flow liquid flow channel is formed on the condensation surface of the condensation fin, and the turbulent liquid flow channel is cooled from the surface, thereby realizing the synergistic effect.

Description

Storage tank oil gas inhibition recovery device and method based on radiation refrigeration and multistage cold trap Technical Field The invention relates to a storage tank oil gas inhibition recovery device and method based on radiation refrigeration and a multistage cold trap, and belongs to the technical field of petrochemical environment-friendly equipment. Background In petrochemical industry, crude oil and finished oil storage tanks are affected by day and night temperature difference and solar radiation in the storage process, and the temperature and pressure of gas in the tanks change. When the temperature rises in the daytime, the expansion pressure of the oil gas in the tank is increased, and the oil gas is discharged to the atmosphere through the breather valve, so that an 'expiration' process (small breathing loss) is formed. The exhausted gas is rich in Volatile Organic Compounds (VOCs) with high concentration, which not only causes serious resource waste, but also is an important source of atmospheric pollution (such as PM2.5 and ozone precursor). Current oil and gas recovery technologies (VRUs) mainly include adsorption, absorption, membrane separation, and condensation methods. However, most of these conventional technologies fall into the category of "end active remediation", with the following problems: 1. The energy consumption is high, and the matched compressor, refrigerating unit or vacuum pump is needed, so that the power consumption is high. 2. The investment and maintenance cost is high, the occupied area is large, the equipment is complex, and the maintenance frequency is high. 3. The applicability is limited, and for remote areas, offshore platforms or monomer storage tanks distributed in a scattered manner, the active recovery technology is difficult to implement due to lack of power supply or difficulty in laying a centralized recovery pipe network. In recent years, radiation refrigeration technology has been attracting attention as an emerging zero-energy refrigeration means. The principle is that heat is directly emitted into cold outer space in an infrared radiation mode through an atmospheric window (8-13 mu m), and most sunlight is reflected, so that a refrigerating effect lower than the ambient temperature can be realized under sunlight. However, the direct application of radiation refrigeration to oil-gas condensation still faces two technical bottlenecks, namely low dew point of light components and limited conventional condensation efficiency under natural temperature difference, and a liquid film formed by condensation is attached to a heat exchange surface, so that heat resistance can be obviously increased and subsequent condensation can be hindered. Disclosure of Invention In order to overcome the defects of the prior art, the invention aims to provide a storage tank oil gas inhibition recovery device and method based on radiation refrigeration and a multistage cold trap, which utilize space as a natural cold source and combine super oleophobic interface technology to provide a source inhibition (prevention) and synergistic condensation (treatment) double-effect intervention mechanism, and realize efficient condensation and recovery of oil gas discharged from a storage tank under the condition of no need of electric drive. The invention provides a storage tank oil gas inhibition recovery device and method based on radiation refrigeration and multistage cold trap, the technical scheme of the invention is as follows: Storage tank oil gas inhibition recovery unit based on radiation refrigeration and multistage cold trap includes: The bottom of the heat-insulating gas collection cavity (1) is provided with a gas inlet interface (11) and a liquid outlet (12), and the gas inlet interface (11) is used for communicating with a storage tank breather valve; The radiation refrigeration condensation module (2) is covered at the top opening of the heat insulation gas collection cavity (1) in an airtight manner and is used for condensing the oil-gas mixture entering the heat insulation gas collection cavity (1) in a passive radiation refrigeration mode; a backflow liquid guide mechanism (3) communicated with the liquid discharge port (12) and used for guiding the liquid formed by condensation into the storage tank in a single direction, and And the source inhibition precooling loop (6) is communicated with the heat-insulating gas-collecting cavity (1) and the top gas-phase space of the storage tank, and is used for introducing gas in the storage tank into the heat-insulating gas-collecting cavity (1) by utilizing natural heat convection to precool and reflux the gas to the storage tank before the breather valve of the storage tank is opened. The radiation refrigeration condensation module (2) comprises a high heat conduction substrate (21), wherein the high heat conduction substrate (21) is provided with one side facing the outside sky and one side facing the inside of the heat i