High-vacuum desolventizing device

Abstract

The utility model discloses a high-vacuum desolventizing device which comprises a first evaporator, a primary steaming crude oil delivery pump, a second evaporator, a secondary steaming crude oil delivery pump, a stripping tower, a stripping crude oil delivery pump, a high-vacuum desolventizing tank and a crude oil delivery pump. Wherein an energy-saving heat exchanger is connected between the first crude oil steaming delivery pump and the second evaporator. The first evaporator, the second evaporator and the stripping tower are respectively connected with a vacuum system; and the top of the high-vacuum desolventizing tank is sequentially connected with a high-vacuum system consisting of a vacuum condenser and a liquid ring vacuum pump. According to the high-vacuum desolventizing device, the high-vacuum desolventizing device is used for removing a large amount of solvent in mixed oil in the leaching process of oil materials such as soybeans and rapeseeds. Parts of equipment of the high-vacuum desolventizing device are connected with a high-vacuum system, so that the use amount of direct steam is greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of oil processing, in particular to a device which adopts high vacuum technology in the oil processing field to remove a large amount of solvent in leached mixed oil. Background Art

[0002] Extraction of vegetable oil by leaching is a modern oil extraction method. This oil production method has the advantages of high oil yield, high protein content in meal, low processing cost, high automation, good production environment, and good quality of crude oil. The extraction method uses solvent to immerse the oil. The liquid part obtained by leaching is called mixed oil, and the solid part is called wet meal.

[0003] Mixed oil is composed of volatile solvent, non-volatile oil dissolved in it and lipid compounds accompanying the oil. The purpose of mixed oil treatment is to separate the solvent and obtain a relatively pure crude oil. According to the difference in boiling points between the solvent and the oil, the mixed oil is evaporated and stripped to convert the low-boiling-point volatile solvent into solvent vapor, and then the solvent vapor is extracted through a vacuum system to separate it from the high-boiling-point non-volatile oil. The solvent vapor can be recycled after condensation.

[0004] During the evaporation and stripping of the mixed oil, the temperature should be kept as low as possible and the time should be kept as short as possible to fully separate the solvent from the mixed oil to avoid thermal deterioration and affect the quality of the extracted crude oil. At the same time, it is also necessary to fully consider the steam consumption of the mixed oil treatment process and improve the production capacity of the equipment.

[0005] Therefore, minimizing steam consumption while effectively removing solvent from mixed oil is increasingly valued in the mixed oil treatment process. Utility Model Content

[0006] Therefore, the technical problem to be solved by the utility model is to provide a mixed oil solvent removal device using a high vacuum system, namely a high vacuum desolventizing device, in view of the shortcomings existing in the prior art.

[0007] The technical solution of the utility model is a high vacuum desolventizing device, comprising a vacuum system, wherein the vacuum system is connected to the mixed oil solvent removing device; the mixed oil solvent removing device comprises a first evaporator, a second evaporator, a stripping tower and a high vacuum desolventizing tank. The first evaporator is sequentially connected to a crude oil delivery pump and a cold side inlet of an energy-saving heat exchanger through a pipeline; the cold side outlet of the energy-saving heat exchanger is sequentially connected to a second evaporator and a second crude oil delivery pump through a pipeline; the second crude oil delivery pump is sequentially connected to a stripping tower and a crude oil delivery pump through a pipeline; the crude oil delivery pump is sequentially connected to a high vacuum desolventizing tank and a crude oil delivery pump through a pipeline; the crude oil delivery pump is connected to a hot side inlet of the energy-saving heat exchanger through a pipeline.

[0008] A high vacuum desolventizing device, wherein the first evaporator is a falling film evaporator; a flash tank is provided below the first evaporator.

[0009] A high vacuum desolventizing device, wherein the second evaporator is a rising film evaporator; a flash tank is arranged above the second evaporator.

[0010] A high vacuum desolventizing device, wherein the first evaporator, the second evaporator and the stripping tower are respectively connected to the vacuum system through pipelines.

[0011] A high vacuum desolventizing device, wherein the high vacuum desolventizing tank is connected to a vacuum condenser through a pipeline, and the vacuum condenser is connected to a liquid ring vacuum pump. The vacuum condenser and the liquid ring vacuum pump constitute a high vacuum system.

[0012] A high vacuum desolventizing device, wherein the liquid ring vacuum pump is connected to a tail gas treatment system. The liquid ring vacuum pump is connected to the tail gas treatment system through a pipeline.

[0013] A high vacuum desolventizing device, wherein the first evaporator is provided with an inlet for indirect steam or DT secondary steam; the second evaporator is provided with an inlet for indirect steam; and the stripping tower is provided with an inlet for direct steam.

[0014] A high vacuum desolventizing device, wherein a nozzle, a plurality of fillers and a plurality of mammoth pumps are provided inside the high vacuum desolventizing tank.

[0015] A high vacuum desolventizing device, wherein the vacuum condenser is connected to a cooling water pipeline.

[0016] A high vacuum desolventizing device, wherein the vacuum condenser and the liquid ring vacuum pump are respectively connected to a solvent recovery system through pipelines.

[0017] Beneficial Effects

[0018] Compared with the prior art, the high vacuum desolventizing device involved in the utility model has the following beneficial effects: the evaporation and stripping of the mixed oil in the device are carried out under negative pressure conditions, which can reduce the boiling point of the mixed oil. At the same time, the application of the high vacuum system and the high vacuum desolventizing tank further reduces the boiling point of the mixed oil, making it easier to remove the solvent. On the premise of fully removing the solvent from the mixed oil, the direct steam consumption of the device is significantly reduced.

[0019] The advantage of this device over the traditional process is that it adds a high vacuum desolventizing tank, so the load of the front stripping tower is reduced (less steam is used to reach a solvent content of 600-1000ppm in the mixed oil, and it does not need to be less than 50ppm). The high vacuum desolventizing tank at the back has a good vacuum degree and a lower temperature, which means that less steam is needed to achieve a solvent content of less than 50ppm in the final mixed oil. High temperature for a long time will produce trans acid, and the use of a vacuum system can avoid this problem.

[0020] The utility model device completes the removal of the solvent in the mixed oil at a relatively low temperature and in a relatively short time, effectively avoiding a series of chemical reactions such as thermal oxidation, thermal decomposition, thermal polymerization and hydrolysis of the oil caused by being exposed to high temperature for a long time, so the crude oil produced is of good quality and is conducive to subsequent refining processing.

[0021] Compared with the prior art, the utility model device has lower moisture content in the desolventized crude oil, exchanges heat with the first distilled crude oil through the energy-saving heat exchanger, the energy-saving heat exchanger is not easy to gel, the heat transfer effect is improved, and the steam usage of the second evaporator can be reduced.

[0022] The utility model device involves less newly added equipment, and both the initial investment cost and the later operation and maintenance cost are low, but creates considerable and sustainable economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a process schematic diagram of the high vacuum desolventizing device according to the utility model.

[0024] In the figure, 1. the first evaporator; 2. a crude oil delivery pump; 3. an energy-saving heat exchanger; 4. the second evaporator; 5. a second crude oil delivery pump; 6. a stripping tower; 7. a stripping crude oil delivery pump; 8. a high vacuum desolventizing tank; 9. a crude oil delivery pump; 10. a vacuum condenser; 11. a liquid ring vacuum pump. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] Reference Figure 1A high vacuum desolventizing device comprises: a first evaporator 1 and a crude oil delivery pump 2, a second evaporator 4 and a second crude oil delivery pump 5, a stripping tower 6 and a crude oil delivery pump 7, a high vacuum desolventizing tank 8 and a crude oil delivery pump 9. An energy-saving heat exchanger 3 is connected between the crude oil delivery pump 2 and the second evaporator 4. The first evaporator 1, the second evaporator 4 and the stripping tower 6 are respectively connected to a vacuum system; the top of the high vacuum desolventizing tank 8 is sequentially connected to a high vacuum system consisting of a vacuum condenser 10 and a liquid ring vacuum pump 11.

[0027] The bottom end of the first evaporator 1 is connected to the inlet of a crude oil delivery pump 2 through a pipeline; the outlet of the crude oil delivery pump 2 is connected to the cold side inlet of the energy-saving heat exchanger 3 through a pipeline; the cold side outlet of the energy-saving heat exchanger 3 is connected to the bottom end of the second evaporator 4 through a pipeline; the flash tank of the second evaporator 4 is connected to the inlet of a second crude oil delivery pump 5 through a pipeline; the outlet of the second crude oil delivery pump 5 is connected to the distributor of the stripping tower 6 through a pipeline; the bottom end of the stripping tower 6 is connected to the inlet of the stripping crude oil delivery pump 7 through a pipeline; the outlet of the stripping crude oil delivery pump 7 is connected to the nozzle of the high vacuum desolventizing tank 8 through a pipeline; the bottom of the high vacuum desolventizing tank 8 is connected to the inlet of the crude oil delivery pump 9 through a pipeline; the outlet of the crude oil delivery pump 9 is connected to the hot side inlet of the energy-saving heat exchanger 3 through a pipeline.

[0028] The first evaporator 1 is a falling film evaporator, the lower end of which includes a flash tank;

[0029] The second evaporator 4 is a rising film evaporator, the upper end of which includes a flash tank;

[0030] The flash tank of the first evaporator 1, the flash tank of the second evaporator 4 and the top of the stripping tower 6 are connected to the vacuum system through pipelines respectively.

[0031] The top of the high vacuum desolventizing tank 9 is connected to the shell side inlet of the vacuum condenser 10 through a pipeline; the shell side outlet of the vacuum condenser 10 is connected to the inlet of the liquid ring vacuum pump 11 through a pipeline; the outlet of the liquid ring vacuum pump 11 is connected to the exhaust gas treatment system through a pipeline.

[0032] The shell side of the first evaporator 1 is connected to indirect steam or DT secondary steam through a pipeline; the shell side of the second evaporator 4 is connected to indirect steam through a pipeline; and the bottom of the stripping tower 6 is connected to direct steam through a pipeline.

[0033] A nozzle, a plurality of fillers and a plurality of mammoth pumps are installed inside the high vacuum desolventizing tank 8. The bottoms of the mammoth pumps are respectively connected with direct steam through pipelines.

[0034] The tube side of the vacuum condenser 10 is connected with cooling water through a pipeline.

[0035] The shell side of the vacuum condenser 10 and the liquid ring vacuum pump 11 are respectively connected to a solvent recovery system through pipelines.

[0036] The process flow of a high vacuum desolventizing device of the utility model is as follows:

[0037] After the oils such as soybean and rapeseed are leached by solvent, a mixed oil with a concentration of 30-40% is obtained, which contains a small amount of impurities and a large amount of solvent. After filtering and removing impurities, the mixed oil enters the top of the first evaporator and flows downward in a film-like manner along the heating tubes under the action of gravity. Under vacuum conditions, indirect steam or DT secondary steam is introduced into the first evaporator, and the solvent in the mixed oil is heated, evaporated and vaporized, and enters the vacuum system. The first distilled crude oil with a concentration of 75-90% is discharged from the bottom of the first evaporator, transported to the energy-saving heat exchanger through a distilled crude oil delivery pump for heat exchange with the high-temperature finished crude oil, and then fed from the bottom of the second evaporator. Also under vacuum conditions, the solvent evaporates and rises after indirect steam heating into the flash tank, and more solvent is evaporated and vaporized, entering the vacuum system, and the second distilled crude oil with a concentration of about 98% is obtained at the same time. The double distilled crude oil is transported to the distributor at the top of the stripping tower by the double distilled crude oil delivery pump. The solvent is stripped with direct steam under vacuum conditions. The content of the solvent in the stripped crude oil is reduced to 600-1000ppm, and its concentration is further improved.

[0038] Since the content of solvent in the stripping crude oil is very low, it is easier to achieve high vacuum by transporting it to the high vacuum desolventizing tank through the stripping crude oil delivery pump. At this time, the mammoth pump inside the high vacuum desolventizing tank only needs to pass a small amount of direct steam to further strip the solvent, and finally obtain a high-temperature desolventized crude oil with a solvent content of less than 50ppm and a moisture content of less than 0.05%. The crude oil delivery pump transports the high-temperature desolventized crude oil from the bottom discharge port of the high vacuum desolventizing tank to the energy-saving heat exchanger for heating the steamed crude oil.

[0039] The high vacuum desolventizing tank achieves high vacuum by connecting the vacuum condenser and the liquid ring vacuum pump. The solvent vapor stripped by the mammoth pump enters the shell side of the vacuum condenser through the pipeline, and the cooling water enters the tube side of the vacuum condenser. The solvent vapor is cooled by the cooling water to form a solvent condensate which is transported to the solvent recovery system through the pipeline; the non-condensable gas is transported to the exhaust gas treatment system by the vacuum liquid ring pump.

[0040] Through the above operation, a high vacuum desolventizing device provided by the utility model can be realized. The advantages of a high vacuum desolventizing device provided by the utility model are as follows:

[0041] (1) Compared with the prior art, the device of the utility model has a lower requirement for the solvent content in the mixed oil obtained by stripping in the stripping tower. The solvent content of the finished crude oil directly obtained by evaporation and stripping of the mixed oil in the prior art is below 50ppm; the utility model adopts a high vacuum desolventizing device, which requires the solvent content of the stripped crude oil obtained after stripping to be between 600 and 1000ppm, thereby significantly reducing the direct steam consumption for stripping.

[0042] (2) The solvent content in the crude oil stripped by the utility model device is between 600 and 1000 ppm, which is easier to achieve high vacuum compared with the prior art where the solvent content in the mixed oil after the second distillation and desolventization is about 20000 ppm. At this time, only a small amount of direct steam is needed to further strip the solvent, and finally obtain high-quality crude oil with a solvent content of less than 50 ppm and a water content of less than 0.05%.

[0043] (3) The moisture content of the crude oil of the finished product of the utility model device is lower. After heat exchange with the first distilled crude oil through the energy-saving heat exchanger, the energy-saving heat exchanger is not easy to gel, which improves the heat transfer effect, better realizes heat energy recovery, and saves the steam consumption of the second evaporator.

[0044] (4) The device of the utility model can remove the solvent from the mixed oil at a relatively low temperature and in a relatively short time, thereby effectively avoiding a series of chemical reactions such as thermal oxidation, thermal decomposition, thermal polymerization and hydrolysis of the oil caused by being exposed to high temperature for a long time. Therefore, the crude oil produced is of good quality, which is conducive to subsequent refining processing.

[0045] (5) The device of the utility model involves less new equipment, and both the initial investment cost and the subsequent operation and maintenance cost are low, while creating considerable and sustainable economic benefits.

[0046] The number of devices and processing scale described here are used to simplify the description of the utility model. The application, modification and variation of the utility model are obvious to those skilled in the art.

[0047] Although the implementation scheme of the utility model has been disclosed as above, it is not limited to the applications listed in the specification and implementation scheme. It can be fully applied to various fields suitable for the utility model. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the utility model is not limited to the specific details and the illustrations shown and described here.

Claims

1. A high vacuum desolventizing device, comprising a vacuum system, characterized in that: The vacuum system is connected to a mixed oil solvent removal device; the mixed oil solvent removal device comprises a first evaporator (1), a second evaporator (4), a stripping tower (6) and a high vacuum desolventizing tank (8); the first evaporator (1) is connected to a crude oil delivery pump (2) and a cold side inlet of an energy-saving heat exchanger (3) in sequence through a pipeline; the cold side outlet of the energy-saving heat exchanger (3) is connected to a second evaporator (4) and a second crude oil delivery pump (5) in sequence through a pipeline; the second crude oil delivery pump (5) is connected to a stripping tower (6) and a crude oil stripping delivery pump (7) in sequence through a pipeline; the crude oil stripping delivery pump (7) is connected to a high vacuum desolventizing tank (8) and a crude oil delivery pump (9) in sequence through a pipeline; the crude oil delivery pump (9) is connected to the hot side inlet of the energy-saving heat exchanger (3) through a pipeline.

2. A high vacuum desolventizing device according to claim 1, characterized in that: The first evaporator (1) is a falling film evaporator; a flash tank is provided below the first evaporator (1).

3. A high vacuum desolventizing device according to claim 1, characterized in that: The second evaporator (4) is a rising film evaporator; a flash tank is provided above the second evaporator (4).

4. A high vacuum desolventizing device according to claim 1, characterized in that: The first evaporator (1), the second evaporator (4) and the stripping tower (6) are respectively connected to the vacuum system through pipelines.

5. A high vacuum desolventizing device according to claim 1, characterized in that: The high vacuum desolventizing tank (8) is connected to a vacuum condenser (10) via a pipeline, and the vacuum condenser (10) is connected to a liquid ring vacuum pump (11).

6. A high vacuum desolventizing device according to claim 5, characterized in that: The liquid ring vacuum pump (11) is connected to the tail gas treatment system.

7. A high vacuum desolventizing device according to claim 1, characterized in that: The first evaporator (1) is provided with an inlet for indirect steam or DT secondary steam; the second evaporator (4) is provided with an inlet for indirect steam; and the stripping tower (6) is provided with an inlet for direct steam.

8. A high vacuum desolventizing device according to claim 1, characterized in that: The high vacuum desolventizing tank (8) is provided with a nozzle, a plurality of fillers and a plurality of mammoth pumps inside.

9. A high vacuum desolventizing device according to claim 5, characterized in that: The vacuum condenser (10) is connected to a cooling water pipeline.

10. A high vacuum desolventizing device according to claim 5, characterized in that: The vacuum condenser (10) and the liquid ring vacuum pump (11) are respectively connected to a solvent recovery system via pipelines.

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