Condensation separator, condensation method oil-gas separation system and application thereof

Abstract

The invention relates to the technical field of oil-gas separation, in particular to a condensation separator, a condensation method oil-gas separation system and application of the condensation method oil-gas separation system. The condensation separator comprises a cylinder (1), a cone (2) and a liquid discharge pipe (3) which are connected in sequence, and further comprises an exhaust pipe (4) arranged in the cylinder (1), a tangential inlet (5) is formed in the cylinder (1), a cooling jacket (6) is arranged outside the cylinder (1), and smooth bulges (7) are arranged on the inner wall of the cylinder (1). The condensation separator provided by the invention solves the problems of long flow and large equipment volume of the existing VOCs condensation recovery method, and can accelerate condensation and liquefaction of VOCs in waste oil gas, improve the condensation effect and realize efficient separation of VOCs in waste oil gas.

Description

Technical Field

[0001] The invention relates to the technical field of oil-gas separation, and in particular to a condensation separator, a condensation oil-gas separation system and applications thereof. Background Art

[0002] Volatile organic compounds (VOCs) generally refer to all volatile organic compounds, while in the environmental sense, they specifically refer to those volatile organic compounds that pollute the ecological environment. Volatile organic compounds in the environmental sense are toxic and have great harm to the environment. Some of them even have carcinogenic, teratogenic and mutagenic effects on organisms. They have been listed as priority pollutants by countries around the world.

[0003] The petrochemical industry is one of the main sources of VOCs emissions, accounting for about 40% by weight of industrial source VOCs emissions. VOCs in the petrochemical industry mainly come from the evaporation of finished oil and liquid chemical products (e.g., gasoline, solvent oil, benzene) processed from petroleum as raw materials. These gases are easily volatilized into the atmosphere during storage, loading and unloading, and transportation, forming oil and gas VOCs.

[0004] At present, common VOCs treatment technologies include combustion, adsorption, absorption, plasma catalysis, photocatalysis, biological method and condensation method. Among them, the condensation method is based on the physical properties of VOCs, using a multi-stage continuous cooling method to reduce the temperature of VOCs, condense VOCs into liquid, and then use a gas-liquid separator to achieve recovery. This method has good safety, high oil and gas recovery rate, significant resource recovery value and compatibility with other good technologies. It has become the preferred method for treating high-concentration VOCs waste gas.

[0005] However, the current VOCs condensation recovery method generally adopts two-stage or three-stage cooling, and the condensed oil and gas after condensation need to be separated into gas and liquid, which has problems such as long process, large equipment size, high condensation energy consumption and poor operating stability.

[0006] Therefore, there is an urgent need for a VOCs recovery device and method with a short process, small volume, low condensation energy consumption, simple operation and stable operation to solve the problem of emission or recovery of fugitive VOCs in the petrochemical industry. Summary of the invention

[0007] The purpose of the present invention is to solve the problems of long process, large equipment volume, high condensation energy consumption and poor operation stability in the current VOCs condensation recovery method, and to provide a condensation separator, a condensation oil and gas separation system and its application.

[0008] In order to achieve the above-mentioned purpose, the first aspect of the present invention provides a condensation separator, wherein the condensation separator includes a cylinder 1, a cone 2 and a drain pipe 3 connected in sequence, and also includes an exhaust pipe 4 arranged in the cylinder 1; a tangential inlet 5 is arranged on the cylinder 1, a cooling jacket 6 is arranged outside the cylinder 1, and a smooth protrusion 7 is arranged on the inner wall of the cylinder 1.

[0009] The second aspect of the present invention provides a condensation oil-gas separation system, wherein the system comprises: a fan 100, the condensation separator 200 described in the first aspect of the present invention, a refrigerator 300 and an adsorption tank 400; wherein the fan 100 is connected to the tangential inlet of the condensation separator 200, the refrigerator 300 is connected to the condensate inlet of the condensation separator 200, and the adsorption tank 400 is connected to the exhaust pipe of the condensation separator 200.

[0010] The third aspect of the present invention provides an application of the condensation oil-gas separation system described in the second aspect of the present invention in removing VOCs from waste oil and gas.

[0011] Through the above technical solution, the beneficial technical effects achieved by the present invention are as follows:

[0012] 1) The condensation separator provided by the present invention, based on the traditional cyclone separation and oil and gas VOCs characteristics, strengthens the condensation process and uses the centrifugal force and gravity in the cyclone separation to achieve the integrated condensation and separation of VOCs, eliminating the gas-liquid separation operation after the traditional VOCs condenser, and solving the problems of the existing VOCs condensation recovery method with long process and large equipment volume;

[0013] 2) The condensation separator provided by the present invention can significantly accelerate the liquefaction speed of VOCs in the waste oil gas by arranging a cooling jacket outside the cylinder and arranging smooth protrusions on the inner wall of the cylinder, and significantly improve the condensation effect and separation effect of VOCs in the waste oil gas;

[0014] 3) The condensation separator provided by the present invention has fins arranged on the outer wall of the cylindrical tube section wrapped by the cooling jacket, which can increase the heat exchange area, help to further improve the condensation speed and condensation efficiency of VOCs, reduce condensation energy consumption, and improve the separation effect of VOCs;

[0015] 4) The condensation oil-gas separation system provided by the present invention utilizes a condensation separator to condense waste oil gas containing VOCs, which can shorten the multi-stage condensation operation process, requiring only one condensation operation, and can increase the heat exchange efficiency between the waste oil gas containing VOCs and the condensate during the condensation operation, significantly improving the condensation efficiency, so that the condensation separator has a VOCs removal efficiency of more than 95% in waste oil gas containing VOCs, and is suitable for industrial promotion;

[0016] 5) The condensation oil-gas separation system provided by the present invention has the technical advantages of simple and efficient process flow, small equipment footprint and easy operation, strong operational stability, and good economic benefits. It is particularly suitable for treating waste oil and gas containing VOCs, and will not cause secondary pollution while efficiently recovering VOCs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a condensation separator provided in the present invention;

[0018] Figure 2 It is a schematic structural diagram of the inner wall of a cylinder provided in the present invention;

[0019] Figure 3 It is a schematic structural diagram of the outer wall of a cylinder provided in the present invention;

[0020] Figure 4 It is a structural schematic diagram of a condensation separator in a preferred embodiment provided in the present invention;

[0021] Figure 5 It is a structural schematic diagram of a condensation method oil and gas separation system provided in the present invention.

[0022] Description of Reference Numerals

[0023] 1. Cylinder 2. Cone 3. Drain pipe

[0024] 4. Exhaust pipe 5. Tangential inlet 6. Cooling jacket

[0025] 7. Protrusion 8. Fin 9. Condensate inlet

[0026] 10. Condensate outlet 11. Upper cover 12. Lower cover

[0027] 100, fan 200, condensation separator 300, refrigerator

[0028] 400, adsorption tank 500, storage tank 600, oil recovery pump DETAILED DESCRIPTION

[0029] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0030] The first aspect of the present invention provides a condensation separator, wherein the condensation separator comprises a cylinder 1, a cone 2 and a drain pipe 3 connected in sequence, and also comprises an exhaust pipe 4 arranged in the cylinder 1; a tangential inlet 5 is arranged on the cylinder 1, a cooling jacket 6 is arranged outside the cylinder 1, and a smooth protrusion 7 is arranged on the inner wall of the cylinder 1, such as Figure 1 and Figure 2 shown.

[0031] Among them, in the present invention, the inventor of the present invention has found through research that when the condensation separator in the present invention is used to treat waste oil gas, a cooling jacket is wrapped on the outer wall of the cylinder, and protrusions are provided on the inner wall of the cylinder. The characteristic that the viscosity of VOCs increases after the temperature is lowered can be utilized to extend the residence time of the VOCs condensate on the inner wall. This not only significantly improves the condensation effect, but also can further capture and dissolve the VOCs gas with the help of the condensation droplets, thereby achieving efficient separation of VOCs.

[0032] Specifically, the waste oil gas is introduced into the condensation separator at high speed from the tangential inlet. The waste oil gas rotates and moves downward in the strong vortex turbulence field. During the movement, it quickly exchanges heat with the condensate in the cooling jacket, and the VOCs are liquefied to form small droplets. The small droplets can accelerate the diffusion and collision of gas molecules during the rotation process, which helps to improve the condensation efficiency; the rotating small droplets are thrown onto the inner wall of the cylinder under the action of centrifugal force. After contacting the protrusions, the protrusions can gather the droplets, slow down the downward flow speed of the small droplets, and further cool the small droplets, so that the small droplets can capture as many VOCs in the waste oil gas as possible, thereby accelerating the condensation and liquefaction of VOCs in the waste oil gas and achieving efficient separation of VOCs.

[0033] In a preferred embodiment of the present invention, in the overlapping area between the cylinder 1 and the cooling jacket 6, fins 8 are provided on the outer wall of the cylinder 1. Figure 3 shown.

[0034] Among them, in the present invention, fins are arranged on the outer wall of the cylindrical pipe section wrapped by the cooling jacket, which can optimize the fluid flow, increase the heat exchange area, and improve the cooling effect and cooling rate of the condensate, thereby helping to increase the condensation rate of VOCs, reduce the condensation energy consumption of VOCs, and further improve the separation effect of VOCs.

[0035] In a preferred embodiment of the present invention, the present invention does not specifically limit the shape of the fins, and can be one or more of serrated fins, square fins, trapezoidal fins (the cross section of the fins is a trapezoid), straight fins, corrugated fins, and louvered fins. Preferably, the fins are evenly wrapped around the outer wall of the cylinder.

[0036] In a preferred embodiment of the present invention, a condensate inlet 9 and a condensate outlet 10 are provided on the cooling jacket 6 ; preferably, the position of the condensate inlet 9 is lower than that of the condensate outlet 10 .

[0037] In the present invention, the position of the condensate inlet is lower than that of the condensate outlet, and the condensate flows in the cooling jacket from bottom to top, which helps to further improve the condensation effect. Further preferably, the condensate outlet 10 is close to the tangential inlet 5.

[0038] In a preferred embodiment of the present invention, the cooling jacket 6 also wraps the cone 2 and / or the drain pipe 3. In the present invention, compared with providing a cooling jacket on the outer wall of the cylinder alone, providing a cooling jacket on the outer wall of the cylinder and the cone, or on the outer wall of the cylinder, the cone and the drain pipe can further improve the separation effect of VOCs in the waste oil gas.

[0039] In a preferred embodiment of the present invention, the cylinder 1, the cone 2, the drain pipe 3 and the exhaust pipe 4 provided with the tangential inlet 5 are regarded as a separation structure, and the cooling jacket 6 provided with the condensate inlet 9 and the condensate outlet 10 is regarded as a condensation structure. A plurality of separation structures (for example, 2, 3, 4, 5, 6, etc.) may be provided in a condensation structure, and the plurality of separation structures are independent of each other or connected in series, such as Figure 4 shown.

[0040] Among them, in the present invention, by setting up multiple separation structures, the separation effect of the condensation separator can be further improved. In order to facilitate the collection of materials discharged from the drain pipe and the exhaust pipe, preferably, the condensation separator also includes an upper cover 11 and a lower cover 12. Among them, the upper cover 11 is arranged above the cooling jacket to collect the gas discharged from the exhaust pipe; the lower cover 12 is arranged below the cooling jacket to collect the liquid discharged from the drain pipe.

[0041] In a preferred embodiment of the present invention, the condensation separator is made of 316L steel. In the present invention, the condensation separator is made of 316L steel, which can increase the corrosion resistance of the condensation separator, further increase the heat transfer efficiency of the condensation separator, and improve the condensation effect.

[0042] The second aspect of the present invention provides a condensation oil-gas separation system, wherein the system comprises: a fan 100, the condensation separator 200 according to the first aspect of the present invention, a refrigerator 300 and an adsorption tank 400; wherein the fan 100 is connected to the tangential inlet of the condensation separator 200, the refrigerator 300 is connected to the condensate inlet of the condensation separator 200, and the adsorption tank 400 is connected to the exhaust pipe of the condensation separator 200, as shown in FIG. Figure 5 shown.

[0043] Among them, in the present invention, the waste oil gas containing VOCs enters the cylinder at a high speed from the tangential inlet of the condensation separator under the action of the fan, forming a rotating flow field in the cylinder and the cone, and generating interface oscillation. The condensate from the refrigerator enters the cooling jacket from the condensate inlet, and exchanges heat with the rotating waste oil gas in the cylinder and the cone, so that the high-concentration gaseous VOCs in the waste oil gas are rapidly cooled and condensed, and the VOCs are liquefied to form small droplets;

[0044] Small droplets can accelerate the diffusion and collision of gas molecules during the rotation process, which helps to improve the condensation efficiency; the rotating small droplets are thrown onto the inner wall of the cylinder under the action of centrifugal force. After contacting the protrusions, the protrusions can gather the droplets, slow down the downward flow speed of the small droplets, and further cool the small droplets, so that the small droplets can capture as many VOCs in the waste oil and gas as possible, thereby accelerating the condensation and liquefaction of VOCs in the waste oil and gas and separating them efficiently;

[0045] The droplets on the inner wall of the cylinder enter the cone under the action of gravity, and continue to flow downward along the inner wall of the cone, and finally flow out from the bottom of the drain pipe to form condensed oil, thereby achieving the removal of more than 95% of VOCs in the waste oil gas;

[0046] The gaseous components after VOCs removal form an inner vortex flow in the cone and cylinder, flow from bottom to top, and are discharged from the upper end of the exhaust pipe to form a primary purified gas; the primary purified gas then enters the adsorption tank, which is filled with adsorbent, which can be used to adsorb a small amount of VOCs carried in the primary purified gas, thereby further purifying the primary purified gas.

[0047] In a preferred embodiment of the present invention, the fan 100 is a compression fan. In the present invention, the compression fan can compress the waste oil gas containing VOCs and introduce the waste oil gas containing VOCs into the condensation separator at a high speed. Compression can prevent VOCs from escaping during transportation, thereby preventing secondary pollution.

[0048] In a preferred embodiment of the present invention, the adsorption tank 400 includes a plurality, preferably two, and each adsorption tank 400 is connected in parallel.

[0049] Among them, in the present invention, when two adsorption tanks are provided, the two adsorption tanks are used in one and reserved in the other, and are not used at the same time. The adsorption tank is filled with adsorption material, and the present invention does not specifically limit the adsorption material. Any adsorption material that can adsorb VOCs can be used in the present invention. For example, the adsorption material can be one or more of activated carbon, molecular sieve, clay, and metal organic framework material.

[0050] In a preferred embodiment of the present invention, the system further comprises a storage tank 500 and an oil recovery pump 600; wherein the storage tank 500 is connected to a drain pipe of the condensation separator 200, and the oil recovery pump 600 is connected to the storage tank 500.

[0051] Among them, in the present invention, the storage tank is used to store condensed oil (ie, liquid VOCs), and the recovery oil pump is used to transport the condensed oil to the recovery oil tank or the recovery oil reprocessing link for use or secondary processing.

[0052] In a preferred embodiment of the present invention, the fan 100, the condensation separator 200, the refrigerator 300, the adsorption tank 400, the storage tank 500 and the oil recovery pump 600 are connected through a process pipeline.

[0053] The third aspect of the present invention provides an application of the condensation oil-gas separation system described in the second aspect of the present invention in removing VOCs from waste oil and gas.

[0054] Among them, the condensation oil-gas separation system provided in the present invention is particularly suitable for treating waste oil and gas containing VOCs with low saturated vapor pressure. For example, the waste oil and gas containing VOCs can be one or more of alkane waste oil and gas, olefin waste oil and gas, alcohol waste oil and gas, ester waste oil and gas, aldehyde waste oil and gas, benzene-containing waste oil and gas, and organic chloride waste oil and gas in the fields of petrochemicals and petroleum refining. Preferably, the content of VOCs in the waste oil and gas containing VOCs is 1000-1000000mg / Nm 3 .

[0055] The present invention will be described in detail below by way of examples. Figure 5 The structure of the condensation separator is as shown in the system shown in Figure 1-4 shown.

[0056] Example 1

[0057] The waste gas containing VOCs is the waste gas emitted from the #1 crude oil catalytic cracking unit of a Shanghai petrochemical company. The VOCs concentration is 597600 mg / Nm 3 , recorded as #1 waste oil gas.

[0058] #1 Waste oil gas is compressed by a fan at a speed of 3000Nm 3 The volume flow rate of / h enters the cylinder tangentially from the tangential inlet of the condensation separator at a high speed; the condensate with a temperature of -40°C from the refrigerator enters the cooling jacket from the condensate inlet and fills the cooling jacket;

[0059] The VOCs in the waste oil gas are liquefied into small droplets in the condensation separator. Under the action of centrifugal force, the small droplets are thrown onto the inner wall of the cylinder and come into contact with the protrusions. Then, under the action of gravity, the small droplets flow out of the drain pipe to form condensed oil. The condensed oil then enters the storage tank for storage and is then transported to the recovery oil tank by the recovery oil pump.

[0060] The gaseous components from which VOCs have been removed are discharged from the exhaust pipe of the condensation separator to form a primary purified gas; the primary purified gas then enters an adsorption tank filled with activated carbon, which adsorbs a small amount of VOCs carried in the primary purified gas to obtain purified gas.

[0061] Example 2

[0062] Same as Example 1, except that the waste oil gas containing VOCs is the waste oil gas from the #2 storage tank and loading process of a Shanghai Petrochemical Co., Ltd., and the VOCs concentration is 802300 mg / Nm 3 , recorded as #2 waste oil gas.

[0063] #2 Waste oil gas at 600Nm 3 The volume flow rate of / h enters the cylinder at a high speed from the tangential inlet of the condensation separator, and the temperature of the condensate is -40℃.

[0064] Example 3

[0065] Same as Example 1, except that the waste oil gas containing VOCs is from the #3 storage tank of a Shanghai Petrochemical Co., Ltd., and the VOCs concentration is 300000 mg / Nm 3 , recorded as #3 waste oil gas.

[0066] #3 Waste oil gas at 400Nm 3 The volume flow rate of / h enters the cylinder at a high speed from the tangential inlet of the condensation separator, and the temperature of the condensate is -45℃.

[0067] Test Example 1

[0068] The content of VOCs in the condensed oil and purified gas prepared in Examples 1-3 was analyzed using the Anchor VOCs online detection analyzer. The analysis results are shown in Table 1:

[0069] Table 1

[0070] VOCs removal rate / % VOCs recovery amount / kg / h Example 1 98％ 1546 Example 2 97％ 467.7 Example 3 97％ 116.5

[0071] As can be seen from Table 1, the condensation oil-gas separation system provided in the present invention is used to treat waste oil gas containing VOCs, and the VOCs removal efficiency is above 95%.

[0072] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A condensation separator, characterized in that: The condensation separator comprises a cylinder (1), a cone (2) and a liquid discharge pipe (3) which are connected in sequence, and also comprises an exhaust pipe (4) arranged in the cylinder (1); a tangential inlet (5) is arranged on the cylinder (1), a cooling jacket (6) is arranged outside the cylinder (1), and a smooth protrusion (7) is arranged on the inner wall of the cylinder (1).

2. The condensation separator according to claim 1, wherein: In the area where the cylinder (1) and the cooling jacket (6) overlap, fins (8) are arranged on the outer wall of the cylinder (1).

3. The condensation separator according to claim 1 or 2, wherein: The cooling jacket (6) is provided with a condensate inlet (9) and a condensate outlet (10); Preferably, the position of the condensate inlet (9) is lower than the position of the condensate outlet (10).

4. The condensation separator according to any one of claims 1 to 3, wherein: The condensation separator is made of 316L steel.

5. A condensation oil-gas separation system, characterized in that: The system comprises: a fan (100), a condensation separator (200) according to any one of claims 1 to 4, a refrigerator (300) and an adsorption tank (400); The fan (100) is connected to the tangential inlet of the condensation separator (200), the refrigerator (300) is connected to the condensate inlet of the condensation separator (200), and the adsorption tank (400) is connected to the exhaust pipe of the condensation separator (200).

6. The condensation oil-gas separation system according to claim 5, wherein: The fan (100) is a compression type fan.

7. The condensation oil-gas separation system according to claim 5 or 6, wherein: The adsorption tank (400) includes a plurality of adsorption tanks (400), and the adsorption tanks (400) are connected in parallel.

8. The condensation oil-gas separation system according to any one of claims 5 to 7, wherein: The system further comprises a storage tank (500) and an oil recovery pump (600); wherein the storage tank (500) is connected to a discharge pipe of the condensation separator (200), and the oil recovery pump (600) is connected to the storage tank (500).

9. The condensation oil-gas separation system according to any one of claims 5 to 8, wherein: The fan (100), the condensation separator (200), the refrigerator (300), the adsorption tank (400), the storage tank (500) and the oil recovery pump (600) are connected through a process pipeline.

10. Application of a condensation oil-gas separation system in removing VOCs from waste oil and gas.

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