Residual cold recycling oil gas recovery system

Abstract

The utility model provides a waste cold recycling oil gas recovery system, which belongs to the technical field of oil gas recovery and comprises a loading oil gas buffer tank, an outlet of the loading oil gas buffer tank is connected with a shell pass inlet of a waste cold precooler through a pipeline, and a shell pass outlet of the waste cold precooler is connected with an inlet of a liquid nitrogen condenser through a pipeline. And an exhaust port of the liquid nitrogen condenser is connected with the tube pass of the residual cold precooler through a pipeline. According to the utility model, the cooling capacity of low-temperature oil gas can be recovered, and the oil gas is subjected to pre-cooling treatment, so that the problem of pipeline blockage during loading oil gas recovery is effectively solved while resource waste is avoided.

Description

TECHNICAL FIELD

[0001] The utility model belongs to oil gas recovery technical field, especially relate to a waste heat recycling oil gas recovery system. BACKGROUND

[0002] The volatile organic gas generated in the storage or loading process of the volatile petroleum chemical liquid material is collectively referred to as oil gas, and the VOCs content of the oil gas is high, direct emission not only pollutes the environment, but also causes great harm to the human body and a large amount of effective component volatile loss.

[0003] At present, the main oil gas recovery treatment technologies in the field include activated carbon adsorption method, absorption method, membrane separation method, biological filtration method and condensation method. The activated carbon adsorption method has the problems of small adsorption capacity and adsorption saturation in physical adsorption, and with the consumption of the adsorbent, the adsorption capacity becomes weak, and after a period of use, the adsorption capacity may be small or the adsorption function may be lost, so that the VOCs cannot meet the emission standard, and the high-concentration oil gas is easy to condense and cause safety hazards in the adsorption process; the absorption method has a simple process and low equipment investment, but the recovery efficiency is low, and when the environmental protection requirement is high, it is difficult to meet the allowable oil gas emission standard; the equipment occupies a large space and has high energy consumption, and the absorbent consumption is large and needs to be continuously supplemented; the membrane separation technology is a frontier technology in the separation science of modern petroleum chemical science, and has the characteristics of small investment, quick effect, simple process, high recovery rate, low energy consumption and no secondary pollution, has high scientific and technological content, large investment, low domestic rate of membrane and high price, and the service life of the membrane is short, the membrane separation device requires stable flow and stable pressure gas, and the operation requirement is high; the biological filtration method has low removal rate of high-concentration, poor biodegradability and difficult biodegradation VOCs; the condensation method includes mechanical condensation and liquid nitrogen condensation, and the liquid nitrogen condensation has the advantages of high recovery purity, simple equipment process, compact equipment, small space occupation, high automation degree, easy maintenance, good safety and output of liquid oil which can be directly utilized. However, the low-temperature oil gas cold energy is not fully recovered and utilized after the oil gas is recovered to liquid oil at a very low temperature by the traditional condensation method, and the resource is wasted.

[0004] In addition, a large amount of water vapor is easily mixed into the loading oil gas, and when the loading oil gas is condensed and recovered, the water vapor is condensed into ice in the low-temperature environment, thereby blocking the pipeline and affecting the normal use of the recovery system. UTILITY MODEL CONTENT

[0005] In view of the defects or deficiencies in the prior art, the utility model provides a waste heat recycling oil gas recovery system which can recover the cold energy of the low-temperature oil gas, pre-cool the oil gas, avoid resource waste and effectively solve the problem of pipeline blockage during the loading oil gas recovery.

[0006] To achieve the above purpose, the utility model adopts the following technical scheme:

[0007] The embodiment of the utility model provides a kind of excess-heat recycling oil gas recovery system, including loading oil gas buffer tank, the outlet of loading oil gas buffer tank is connected with excess-heat pre-cooler shell side inlet by pipeline, excess-heat pre-cooler shell side outlet is connected with the inlet of liquid nitrogen condenser by pipeline, and the exhaust of liquid nitrogen condenser is connected with excess-heat pre-cooler tube side by pipeline.

[0008] Further, gas-liquid separator and non-condensable gas pre-cooler are sequentially connected on the pipeline between excess-heat pre-cooler shell side outlet and liquid nitrogen condenser inlet, excess-heat pre-cooler shell side outlet is connected with the inlet of gas-liquid separator, the exhaust of gas-liquid separator is connected with non-condensable gas pre-cooler shell side inlet, and the shell side outlet of non-condensable gas pre-cooler is connected with the inlet of liquid nitrogen condenser.

[0009] Further, the exhaust of liquid nitrogen condenser is also connected with non-condensable gas pre-cooler tube side by pipeline.

[0010] Further, loading tail gas booster fan is arranged on the pipeline between the outlet of loading oil gas buffer tank and excess-heat pre-cooler shell side inlet.

[0011] Further, gas-liquid separator is connected on the pipeline between excess-heat pre-cooler shell side outlet and non-condensable gas pre-cooler shell side inlet, excess-heat pre-cooler shell side outlet is connected with the inlet of gas-liquid separator, and the exhaust of gas-liquid separator is connected with non-condensable gas pre-cooler shell side inlet.

[0012] Further, tank area oil gas buffer tank is also included, the outlet of tank area oil gas buffer tank is connected with cold nitrogen gas pre-cooler shell side inlet, and the tube side outlet of cold nitrogen gas pre-cooler is connected with the inlet of gas-liquid separator.

[0013] Further, tank area tail gas booster fan is arranged on the pipeline between the outlet of tank area oil gas buffer tank and cold nitrogen gas pre-cooler shell side inlet.

[0014] Further, the tube side outlet of the excess-heat pre-cooler is connected with incinerator.

[0015] Further, the liquid nitrogen inlet of the liquid nitrogen condenser is connected with liquid nitrogen storage tank, the liquid nitrogen outlet of the liquid nitrogen condenser is connected with the tube side inlet of cold nitrogen gas pre-cooler, and the tube side outlet of the cold nitrogen gas pre-cooler is connected with nitrogen gas buffer tank.

[0016] Further, two excess-heat pre-coolers are arranged, two excess-heat pre-coolers are installed in parallel, and two excess-heat pre-coolers are connected with steam heater.

[0017] Compared with prior art, the utility model has the beneficial effects that:

[0018] The utility model discloses a buffer tank for tank car oil gas, which is connected with the shell side of a waste heat pre-cooler, and the tube side of the waste heat pre-cooler is connected with a liquid nitrogen condenser.

[0019] 2、The outlet of the tank area oil gas buffer tank is connected with the inlet of the cold nitrogen pre-cooler shell side, and the liquid nitrogen outlet of the liquid nitrogen condenser is connected with the cold nitrogen pre-cooler shell side, so that the tank area oil gas is pre-cooled by using the cold energy of the liquid nitrogen, thereby realizing recycling of the cold energy of the liquid nitrogen and avoiding resource waste.

[0020] 3、The utility model discloses a waste heat pre-cooler, two waste heat pre-coolers are connected with the steam heater, when the pressure difference between the inlet and the outlet of one of the waste heat pre-coolers reaches a set value during operation, the system is automatically switched to the other waste heat pre-cooler, the steam heater uses low-pressure steam to heat nitrogen, and the waste heat pre-cooler is defrosted by using the heated nitrogen, thereby avoiding that part of the water in the tank car oil gas is frozen at a condensation temperature of-10 to-20 DEG C, and ensuring normal operation of the system. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The utility model discloses an oil gas recovery system structure schematic view in embodiment.

[0022] 1, tank car oil gas buffer tank;2, waste heat pre-cooler;3, tank area oil gas buffer tank;4, cold nitrogen pre-cooler;5, gas-liquid separator;6, non-condensable gas pre-cooler;7, liquid nitrogen condenser;8, liquid nitrogen storage tank;9, nitrogen buffer tank. DETAILED DESCRIPTION

[0023] The utility model is further described below in combination with the drawings and embodiments.

[0024] A typical embodiment of the utility model, for example, Figure 1As shown, a waste heat recycling oil gas recovery system includes a loading oil gas buffer tank 1, oil gas from crude oil, triphenyl, gasoline and diesel loading tanks is collected into the loading oil gas buffer tank 1 through a collecting pipeline, the outlet of the loading oil gas buffer tank 1 is connected to the shell side inlet of a waste heat pre-cooler 2 through a pipeline, and the -100℃ / -120℃ non-condensable gas in the tube side of the waste heat pre-cooler 2 is used for heat exchange to pre-cool the loading oil gas, condense the loading oil gas to -10~-20℃, and condense the loading oil gas into liquid state, while removing more than 90% of the water vapor in the loading oil gas, so that the moisture in the loading oil gas is reduced to 987mg / m 3 , so as to solve the problem of equipment and facility blockage.

[0025] A loading tail gas booster fan is arranged on the pipeline between the outlet of the loading oil gas buffer tank 1 and the shell side inlet of the waste heat pre-cooler 2, and the loading oil gas is pressurized by the loading tail gas booster fan.

[0026] The system also includes a tank area oil gas buffer tank 3, tank area oil gas is collected into the tank area oil gas buffer tank 3 through a collecting pipeline, the outlet of the tank area oil gas buffer tank 3 is connected to the shell side inlet of a cold nitrogen pre-cooler 4, and the cold nitrogen in the tube side of the cold nitrogen pre-cooler 4 is used for heat exchange to condense the tank area oil gas into liquid state, and the tube side outlet of the cold nitrogen pre-cooler 4 is connected to the inlet of a gas-liquid separator 5 to separate the oil gas into gas and liquid.

[0027] A tank area tail gas booster fan is arranged on the pipeline between the outlet of the tank area oil gas buffer tank 3 and the shell side inlet of the cold nitrogen pre-cooler 4, and the tank area oil gas is pressurized by the tank area tail gas booster fan.

[0028] The shell side outlet of the waste heat pre-cooler 2 is connected to the inlet of the gas-liquid separator 5, the oil gas condensed into liquid state is discharged from the liquid outlet of the gas-liquid separator 5 for recycling, the oil gas that cannot be condensed into liquid state is discharged from the gas outlet of the gas-liquid separator 5, the gas outlet of the gas-liquid separator 5 is connected to the shell side inlet of a non-condensable gas pre-cooler 6 for further pre-cooling of the oil gas, the shell side outlet of the non-condensable gas pre-cooler 6 is connected to the inlet of a liquid nitrogen condenser 7, the oil gas is further condensed by the liquid nitrogen condenser 7 to condense the oil gas into liquid state and discharge from the liquid outlet of the liquid nitrogen condenser 7, and the oil gas that has not been condensed into gas state is discharged from the gas outlet of the liquid nitrogen condenser 7 as waste oil gas.

[0029] Since the waste oil gas has high cold energy at this time, in order to recycle the cold energy in the waste oil gas and reduce resource waste, the gas outlet of the liquid nitrogen condenser 7 is connected to the tube side of the non-condensable gas pre-cooler 6 and the waste heat pre-cooler 2 through a pipeline, the waste oil gas is used as non-condensable gas to provide cold energy to the non-condensable gas pre-cooler 6 and the waste heat pre-cooler 2 for pre-cooling of the oil gas, thereby realizing waste oil gas cold energy recycling and solving the problem of low temperature of the waste oil gas and energy waste.

[0030] The pipe passage outlet of the residual cooling pre-cooler 2 is connected with the incinerator, and the waste oil gas finally enters the incinerator for incineration.

[0031] Further, the liquid nitrogen inlet of the liquid nitrogen condenser 7 is connected with the liquid nitrogen storage tank 8, so as to provide liquid nitrogen for the liquid nitrogen condenser 7, the liquid nitrogen exchanges heat with the oil gas in the liquid nitrogen condenser 7, the oil gas is condensed, the liquid nitrogen outlet of the liquid nitrogen condenser 7 is connected with the pipe passage inlet of the cold nitrogen pre-cooler 4, the residual cooling of the liquid nitrogen is utilized to pre-cool the tank area oil gas, so as to reduce the resource waste, and the pipe passage outlet of the cold nitrogen pre-cooler 4 is connected with the nitrogen buffer tank 9, the nitrogen is recycled and stored.

[0032] Further, in order to avoid that part of the water in the loading oil gas is frozen at the condensing temperature of-10℃ to-20℃, the residual cooling pre-cooler 2 is provided with two, the two residual cooling pre-coolers 2 are installed in parallel, the two residual cooling pre-coolers 2 are connected with the steam heater (not shown in the figure), when the pressure difference between the inlet and the outlet of one of the residual cooling pre-coolers 2 reaches a set value during operation, the system is automatically switched to the other residual cooling pre-cooler 2, the steam heater utilizes the low-pressure steam to heat the nitrogen, and the heated nitrogen is utilized to defrost the residual cooling pre-cooler 2, so as to ensure the normal operation of the system.

[0033] In addition, the residual cooling pre-cooler 2 adopts a U-shaped tube structure to cope with the thermal expansion and contraction problem caused by the condensing temperature difference, and the heat exchange tube spacing is increased at the same time to relieve or delay the formation of ice blockage, so as to create conditions for system defrosting and stable operation.

[0034] Further, the two residual cooling pre-coolers 2 are horizontal devices, which are horizontally placed and moderately inclined, so as to facilitate the collection of the condensed liquid.

[0035] The outlet of the loading oil gas buffer tank is connected with the shell passage of the residual cooling pre-cooler, the pipe passage of the residual cooling pre-cooler is connected with the liquid nitrogen condenser, the low-temperature oil gas from the liquid nitrogen condenser enters the pipe passage of the residual cooling pre-cooler, exchanges heat with the loading oil gas in the shell passage of the residual cooling pre-cooler, and pre-cools the loading oil gas, the high-temperature oil gas generated by loading and unloading operations and tank breathing exchanges heat with the low-temperature oil gas at-100℃ / -120℃ in the residual cooling pre-cooler, the loading oil gas is condensed to-10~-20℃, more than 90% of the water vapor in the loading oil gas is removed, the low-temperature oil gas cold energy is recycled and utilized, resource waste is avoided, and the equipment and facility blockage problem is solved.

[0036] The preferred embodiments of the utility model are described above, but the utility model is not limited to the preferred embodiments, and the utility model can be changed and varied for those skilled in the art. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A residual cold reusing oil gas recovery system, characterized in that, The loading oil gas buffer tank is connected with the outlet of the waste heat pre-cooler through a pipeline, and the outlet of the waste heat pre-cooler is connected with the inlet of the liquid nitrogen condenser through a pipeline.

2. The residual cold reusing oil gas recovery system of claim 1, wherein, A gas-liquid separator and a non-condensable gas pre-cooler are connected in sequence on the pipeline between the outlet of the waste heat pre-cooler and the inlet of the liquid nitrogen condenser.

3. The residual cold reusing oil vapor recovery system of claim 1, wherein, The exhaust outlet of the liquid nitrogen condenser is also connected with the tube side of the non-condensable gas pre-cooler through a pipeline.

4. The residual cold reusing oil gas recovery system of claim 1, wherein, A loading tail gas booster fan is arranged on the pipeline between the outlet of the loading oil gas buffer tank and the inlet of the waste heat pre-cooler.

5. A residual cold reusing oil gas recovery system according to claim 2, wherein, A tank area oil gas buffer tank is also provided, and the outlet of the tank area oil gas buffer tank is connected with the inlet of the cold nitrogen gas pre-cooler.

6. A residual cold reusing oil gas recovery system according to claim 5, wherein, The tube side outlet of the cold nitrogen gas pre-cooler is connected with the inlet of the gas-liquid separator.

7. A residual cold reusing oil vapor recovery system as set forth in claim 5, wherein A tank area tail gas booster fan is arranged on the pipeline between the outlet of the tank area oil gas buffer tank and the inlet of the cold nitrogen gas pre-cooler.

8. The residual cold reusing oil vapor recovery system of claim 1, wherein, The tube side outlet of the waste heat pre-cooler is connected with the incinerator.

9. The residual cold reusing oil vapor recovery system of claim 1, wherein, The liquid nitrogen inlet of the liquid nitrogen condenser is connected with a liquid nitrogen storage tank, the liquid nitrogen outlet of the liquid nitrogen condenser is connected with the tube side inlet of the cold nitrogen gas pre-cooler, and the tube side outlet of the cold nitrogen gas pre-cooler is connected with a nitrogen gas buffer tank.

10. The residual cold reusing oil vapor recovery system of claim 1, wherein, Two waste heat pre-coolers are provided, and the two waste heat pre-coolers are installed in parallel and are both connected with a steam heater.

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