Alkali washing demulsification system for high-carbon-number Fischer-Tropsch oil

Abstract

The utility model discloses an alkali wash demulsification system for high carbon number Fischer-Tropsch oil, which comprises an alkali wash demulsification device, a first liquid separation device, a second liquid separation device, a water washing device and a neutralizing device, the alkali wash demulsification device is communicated with the first liquid separation device, the water washing device and the neutralizing device are both communicated with the first liquid separation device, and the neutralizing device is communicated with the second liquid separation device. A liquid inlet of the second liquid separation device is communicated with the washing device, and a liquid outlet of the second liquid separation device is communicated with the neutralizing device. By adopting the alkali washing demulsification system, not only is the yield of oil products effectively improved, but also the acidity of the oil products after water washing is effectively reduced; in addition, the demulsification system is simple in structure, easy to operate and worthy of vigorous popularization and application.

Description

Technical Field

[0001] The utility model belongs to the technical field of demulsification, and in particular relates to an alkali washing demulsification system for high carbon number Fischer-Tropsch oil. Background Art

[0002] Fischer-Tropsch oil usually has a high acid value property, which has a direct impact on the production of downstream fine chemical products and downstream equipment, and must be deacidified. In the existing deacidification process of Fischer-Tropsch oil, alkaline washing and water washing are usually used to deacidify the Fischer-Tropsch oil. The long-chain sodium alkanoate generated by the reaction of the sodium hydroxide solution added during the alkaline washing with the long-chain acid in the high-carbon Fischer-Tropsch oil is the main reason for the production of emulsions. In addition, the long-chain sodium alkanoate is adsorbed on the oil-water interface as a surfactant, preventing water droplets or oil droplets from agglomerating, thereby reducing the recovery rate of the high-carbon Fischer-Tropsch oil after alkaline washing. At the same time, due to the formation of the oil-water emulsion, the acid in the high-carbon Fischer-Tropsch oil does not react fully with the alkaline solution, resulting in a higher acid value for the Fischer-Tropsch oil after alkaline washing and water washing. In addition, a demulsification system that can achieve the goal of increasing the oil yield and reducing the acid value has not been found. Therefore, the development of a new demulsification system is still one of the main themes that existing researchers and researchers are focusing on. Utility Model Content

[0003] In view of this, the purpose of the utility model is to provide an alkali washing and demulsification system for high carbon number Fischer-Tropsch oil, which solves the problem of low oil yield and high acid value caused by emulsification of high carbon number Fischer-Tropsch oil after alkali washing.

[0004] In order to solve the above problems, the technical solution adopted by the utility model is: an alkali washing and demulsification system for high carbon number Fischer-Tropsch oil, comprising an alkali washing and demulsification device, a first liquid separation device, a second liquid separation device, a water washing device and a neutralization device, the alkali washing and demulsification device is connected to the first liquid separation device, the water washing device and the neutralization device are both connected to the first liquid separation device, the liquid inlet of the second liquid separation device is connected to the water washing device, and the liquid outlet of the second liquid separation device is connected to the neutralization device.

[0005] Preferably, the demulsification system further comprises an evaporation device and a distillation device, and the neutralization device is connected to the distillation device through the evaporation device.

[0006] Preferably, the demulsification system further comprises an acid liquid storage device, and the acid liquid storage device is communicated with the neutralization device.

[0007] Preferably, the demulsification system further comprises a raw material auxiliary agent storage device, and the raw material auxiliary agent storage device is communicated with the alkali washing demulsification device.

[0008] Preferably, the raw material additive storage device comprises a Fischer-Tropsch oil storage device, an acid liquid storage device and a demulsifier storage device, and the Fischer-Tropsch oil storage device, the acid liquid storage device and the demulsifier storage device are all connected to the alkali washing and demulsifying device.

[0009] Preferably, the second liquid separation component is a liquid separation tank, and the water outlet end of the liquid separation tank is connected to the pipeline between the first liquid separation component and the neutralization device.

[0010] Preferably, the distillation device comprises a distillation tower and a water storage tank, the distillation tower is connected to the water storage tank, the water storage tank is connected to the water washing device, and the evaporation device is connected to the distillation tower.

[0011] Preferably, the distillation tower is also connected to the demulsifier storage device.

[0012] Preferably, the evaporation device comprises an evaporator and a salt solution storage device, the neutralization device is connected to the distillation tower through the evaporator, and the salt solution storage device is connected to the evaporator.

[0013] Compared with the prior art, the use of the utility model alkaline washing and demulsification system can not only effectively improve the oil yield, but also effectively reduce the acidity of the oil after water washing; in addition, the demulsification system has a simple structure and is easy to operate, and is worthy of vigorous promotion and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic diagram of an alkali washing and demulsification system for high carbon number Fischer-Tropsch oil provided in an embodiment of the utility model.

[0015] In the figure, 1. alkaline washing and demulsifying device, 2. first liquid separation device, 3. second liquid separation device, 4. water washing device, 5. neutralization device, 6. evaporation device, 61. evaporator, 62. salt solution storage device, 7. distillation device, 71. distillation tower, 72. water storage tank, 8. acid storage device, 9. raw material auxiliary agent storage device, 91. acid storage device, 92. acid storage device, 93. demulsifier storage device. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail in combination with specific embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0017] In the description of the present utility model, it should be clarified that the terms "vertical", "lateral", "longitudinal", "front", "rear", "left", "right", "up", "down", "horizontal" and the like indicating orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present utility model, and do not mean that the device or element referred to must have a specific orientation or position, and therefore cannot be understood as a limitation on the present utility model. In the description of the present utility model, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or it can be indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0018] An embodiment of the utility model provides an alkali washing and demulsification system for high carbon number Fischer-Tropsch oil, comprising an alkali washing and demulsification device 1, a first liquid separation device 2, a second liquid separation device 3, a water washing device 4 and a neutralization device 5, wherein the alkali washing and demulsification device 1 is connected to the first liquid separation device 2, the water washing device 4 and the neutralization device 5 are both connected to the first liquid separation device 2, the liquid inlet of the second liquid separation device 3 is connected to the water washing device 4, and the liquid outlet of the second liquid separation device 3 is connected to the neutralization device 5.

[0019] By adopting the above scheme, by adopting the demulsification system of the utility model, not only the oil yield is effectively improved, but also the acidity of the oil after water washing is effectively reduced; in addition, the alkaline washing demulsification system has a simple structure and is easy to operate, and is worthy of vigorous promotion and use.

[0020] Furthermore, the demulsification system further comprises an evaporation device 6 and a distillation device 7 , and the neutralization device 5 is connected to the distillation device 7 via the evaporation device 6 .

[0021] Furthermore, the demulsification system also includes an acid liquid storage device 8 , and the acid liquid storage device 8 is connected to the neutralization device 5 .

[0022] Furthermore, the demulsification system further comprises a raw material auxiliary agent storage device 9 , and the raw material auxiliary agent storage device 9 is connected to the alkali washing demulsification device 1 .

[0023] Furthermore, the raw material additive storage device 9 includes a Fischer-Tropsch oil storage device 91, an acid storage device 92 and a demulsifier storage device 93, and the Fischer-Tropsch oil storage device 91, the acid storage device 92 and the demulsifier storage device 93 are all connected to the alkali washing demulsification device 1; by setting the Fischer-Tropsch oil storage device 91, the acid storage device 92 and the demulsifier storage device 93, and connecting the Fischer-Tropsch oil storage device 91, the acid storage device 92 and the demulsifier storage device 93 with the alkali washing demulsification device 1, it is convenient to automatically add the alkali washing, raw materials and demulsifier to the alkali washing demulsification device 1

[0024] Furthermore, the second liquid separation component 3 is a liquid separation tank, and the water outlet end of the liquid separation tank is connected to the pipeline between the first liquid separation component 2 and the neutralization device 5; by connecting the water outlet end of the liquid separation tank with the pipeline between the first liquid separation component 2 and the neutralization device 5, the purpose of water recycling is effectively achieved.

[0025] Furthermore, the distillation device 7 includes a distillation tower 71 and a water storage tank 72, the distillation tower 71 is connected to the water storage tank 72, the water storage tank 72 is connected to the water washing device 4, and the evaporation device 6 is connected to the distillation tower 71; by setting up the water storage tank 72 and connecting the water storage tank 72 with the water washing device 4, in this way, not only the purpose of collecting water during the distillation process is achieved, but also the recovered water is easily added to the water washing device 4 again, thereby also playing a role of recycling and energy saving and environmental protection.

[0026] Furthermore, the distillation tower 71 is also connected to the demulsifier storage device 93; by connecting the distillation tower 71 to the demulsifier storage device 93, the purpose of recycling the demulsifier is effectively achieved.

[0027] Furthermore, the evaporation device 6 includes an evaporator 61 and a salt solution storage device 62, the neutralization device 5 is connected to the distillation tower 71 through the evaporator 61, and the salt solution storage device 62 is connected to the evaporator 61; by setting up the salt solution storage device 62, the purpose of facilitating the collection of the salt solution during the evaporation process is effectively achieved.

[0028] The present invention also provides an alkali washing and demulsification method for high carbon number Fischer-Tropsch oil using the above demulsification system, which specifically comprises the following steps:

[0029] S1, mixing a high carbon number Fischer-Tropsch oil, an alkali washing liquid and a demulsifier, and performing a deacidification and demulsification treatment to obtain a high carbon number Fischer-Tropsch oil separation liquid after alkali washing and demulsification;

[0030] S2, separating the upper oil phase of the high carbon number Fischer-Tropsch oil separation liquid after demulsification, and washing the upper oil phase with water to obtain a washed oil phase;

[0031] S3, adding acid to the lower aqueous phase of the high carbon number Fischer-Tropsch oil separated liquid after demulsification and the aqueous phase after washing in S2 for neutralization reaction to obtain a neutralized aqueous phase;

[0032] S4, evaporating and desalting the neutralized water phase, and distilling the demulsifier and water under reduced pressure, while the water and the demulsifier are recycled.

[0033] Further, in S1, the high carbon Fischer-Tropsch oil is a high carbon Fischer-Tropsch synthetic oil of C10-C20; in S1, the alkaline washing solution is a 0.5-1.5%wt sodium hydroxide solution; in S1, the volume ratio of the high carbon Fischer-Tropsch oil to the alkaline washing solution is 3-10; in S1, the temperature of the deacidification and demulsification is 20-50°C, and the time of the deacidification and demulsification is 20-50min; in S1, the demulsifier is a sulfoxide and / or sulfone extractant, including one of dimethyl sulfoxide, cyclopentane sulfone, dimethyl sulfone, and diethyl sulfone; in S1, the high carbon number Fischer-Tropsch oil separation liquid after alkaline washing and demulsification and the demulsifier are in an oil-to-agent ratio of 10-50; in S1, the stirring time during the deacidification and demulsification is 10-50min; the temperature of the deacidification and demulsification is 30-50°C; the standing time is 0.3-2h, preferably 0.5h.

[0034] The following are specific embodiments

[0035] Example 1

[0036] High carbon Fischer-Tropsch oil raw material (acidity 280mgKOH / 100mL) was mixed with 1%wt sodium hydroxide solution at a volume oil-to-agent ratio of 5 and a volume dimethyl sulfoxide oil-to-agent ratio of 20 at 30°C for 30min for deacidification and demulsification. After alkaline washing and demulsification, the mixture was allowed to stand for 0.5h. The acidity of the upper oil phase after water washing was 0mgKOH / 100mL, and the oil yield was 99.6%.

[0037] Example 2

[0038] High carbon Fischer-Tropsch oil raw material (acidity 280mgKOH / 100mL) was mixed with 1%wt sodium hydroxide solution at a volume oil-to-agent ratio of 5 and a volume dimethyl sulfoxide oil-to-agent ratio of 20 at 40°C for 30min for deacidification and demulsification. After alkali washing and demulsification, the mixture was allowed to stand for 0.5h. The acidity of the upper oil phase after water washing was 0mgKOH / 100mL, and the oil yield was 99.4%.

[0039] Example 3

[0040] High carbon Fischer-Tropsch oil raw material (acidity 280mgKOH / 100mL) was mixed with 1%wt sodium hydroxide solution at a volume oil-to-agent ratio of 5 and a volume dimethyl sulfoxide oil-to-agent ratio of 20 at 50°C for 30min for deacidification and demulsification. After alkali washing and demulsification, the mixture was allowed to stand for 0.5h. The acidity of the upper oil phase after water washing was 0mgKOH / 100mL, and the oil yield was 99.5%.

[0041] Example 4

[0042] High carbon Fischer-Tropsch oil raw material (acidity 280 mgKOH / 100 mL) was mixed with 1% wt sodium hydroxide solution at a volume oil-to-agent ratio of 5 and a volume dimethyl sulfoxide oil-to-agent ratio of 10 at 30°C for 30 min for deacidification and demulsification. After alkali washing and demulsification, the mixture was allowed to stand for 0.5 h. The acidity of the upper oil phase after water washing was 0 mgKOH / 100 mL, and the oil yield was 99.6%.

[0043] Example 5

[0044] High carbon Fischer-Tropsch oil raw material (acidity 280 mgKOH / 100 mL) was mixed with 1% wt sodium hydroxide solution at a volume oil-to-agent ratio of 5 and a volume dimethyl sulfoxide oil-to-agent ratio of 30 at 30°C for 30 min for deacidification and demulsification. After alkali washing and demulsification, the mixture was allowed to stand for 0.5 h. The acidity of the upper oil phase after water washing was 0 mgKOH / 100 mL, and the oil yield was 99.1%.

[0045] Example 6

[0046] High carbon Fischer-Tropsch oil raw material (acidity 280 mgKOH / 100 mL) was mixed with 1% wt sodium hydroxide solution at a volume oil-to-agent ratio of 5 and a volume dimethyl sulfoxide oil-to-agent ratio of 30 at 30°C for 30 min for deacidification and demulsification. After alkali washing and demulsification, the mixture was allowed to stand for 0.3 h. The acidity of the upper oil phase after water washing was 0 mgKOH / 100 mL, and the oil yield was 99.0%.

[0047] Example 7

[0048] High carbon Fischer-Tropsch oil raw material (acidity 280 mgKOH / 100 mL) was mixed with 1% wt sodium hydroxide solution at a volume oil-to-agent ratio of 5 and a volume dimethyl sulfoxide oil-to-agent ratio of 30 at 30°C for 30 min for deacidification and demulsification. After alkali washing and demulsification, the mixture was allowed to stand for 0.7 h. The acidity of the upper oil phase after water washing was 0 mgKOH / 100 mL, and the oil yield was 99.5%.

[0049] Example 8

[0050] High carbon Fischer-Tropsch oil raw material (acidity 280 mgKOH / 100 mL) was mixed with 1% wt sodium hydroxide solution at a volume oil-to-agent ratio of 5 and a volume dimethyl sulfoxide oil-to-agent ratio of 30 at 30°C for 30 minutes for deacidification and demulsification. After alkaline washing and demulsification, the mixture was allowed to stand for 1 hour, and the oil yield was 99.6%.

[0051] Comparison column 1

[0052] High carbon Fischer-Tropsch oil raw material (acidity 280 mgKOH / 100 mL) was mixed with 1% wt sodium hydroxide solution at a volume oil-to-agent ratio of 5 and a volume dimethyl sulfoxide oil-to-agent ratio of 30 at 20°C for 30 min for deacidification and demulsification. After alkali washing and demulsification, the mixture was allowed to stand for 0.5 h. The acidity of the upper oil phase after water washing was 89 mgKOH / 100 mL, and the oil yield was 33.6%.

[0053] Comparison column 2

[0054] The high carbon Fischer-Tropsch oil raw material was mixed with 1% wt sodium hydroxide solution at a volume oil-to-agent ratio of 5 at 30° C. and stirred for 30 min for deacidification; the acidity after water washing was 123 mg KOH / 100 mL, and the oil yield was 22.4%.

[0055] By comparing the oil yield and acidity value after water washing of Examples 1-11 and Comparative Examples 1-2, it can be seen that by using the demulsification method of the present invention to demulsify the high-carbon Fischer-Tropsch oil, not only the oil yield is effectively improved, the oil yield is as high as more than 99%, but also the acidity of the oil after water washing is effectively reduced, and the lowest acidity reaches 0 mgKOH / 100 mL.

[0056] In summary, by adopting the demulsification method of the present invention to perform alkaline washing and demulsification treatment on high carbon Fischer-Tropsch oil, not only the oil yield is effectively improved, but also the acidity of the oil after water washing is effectively reduced.

[0057] The above is only a preferred specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the utility model should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. An alkali washing and demulsification system for high carbon number Fischer-Tropsch oil, characterized in that: The invention comprises an alkali-washing and demulsifying device (1), a first liquid-separating device (2), a second liquid-separating device (3), a water-washing device (4) and a neutralizing device (5), wherein the alkali-washing and demulsifying device (1) is connected to the first liquid-separating device (2), the water-washing device (4) and the neutralizing device (5) are both connected to the first liquid-separating device (2), the liquid inlet of the second liquid-separating device (3) is connected to the water-washing device (4), and the liquid outlet of the second liquid-separating device (3) is connected to the neutralizing device (5).

2. The alkali washing and demulsification system for high carbon number Fischer-Tropsch oil according to claim 1, characterized in that: The demulsification system further comprises an evaporation device (6) and a distillation device (7), and the neutralization device (5) is connected to the distillation device (7) via the evaporation device (6).

3. The alkali washing and demulsification system for high carbon number Fischer-Tropsch oil according to claim 1 or 2, characterized in that: The demulsification system further comprises an acid liquid storage device (8), wherein the acid liquid storage device (8) is in communication with the neutralization device (5).

4. The alkali washing and demulsification system for high carbon number Fischer-Tropsch oil according to claim 1 or 2, characterized in that: The demulsification system further comprises a raw material auxiliary agent storage device (9), wherein the raw material auxiliary agent storage device (9) is connected to the alkali washing demulsification device (1).

5. The alkali washing and demulsification system for high carbon number Fischer-Tropsch oil according to claim 4, characterized in that: The raw material auxiliary agent storage device (9) includes a Fischer-Tropsch oil storage device (91), an acid liquid storage device (92) and a demulsifier storage device (93), and the Fischer-Tropsch oil storage device (91), the acid liquid storage device (92) and the demulsifier storage device (93) are all connected to the alkali washing and demulsification device (1).

6. The alkali washing and demulsification system for high carbon number Fischer-Tropsch oil according to claim 1, characterized in that: The second liquid separation component (3) is a liquid separation tank, and the water outlet end of the liquid separation tank is connected to the pipeline between the first liquid separation component (2) and the neutralization device (5).

7. The alkali washing and demulsification system for high carbon number Fischer-Tropsch oil according to claim 2, characterized in that: The distillation device (7) comprises a distillation tower (71) and a water storage tank (72), the distillation tower (71) is connected to the water storage tank (72), the water storage tank (72) is connected to the water washing device (4), and the evaporation device (6) is connected to the distillation tower (71).

8. The alkali washing and demulsification system for high carbon number Fischer-Tropsch oil according to claim 7, characterized in that: The distillation tower (71) is also connected to the demulsifier storage device (93).

9. The alkali washing and demulsification system for high carbon number Fischer-Tropsch oil according to claim 2, characterized in that: The evaporation device (6) comprises an evaporator (61) and a salt solution storage device (62); the neutralization device (5) is connected to the distillation tower (71) via the evaporator (61); and the salt solution storage device (62) is connected to the evaporator (61).

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