Separation-enhanced cyclone reactor for alkylation of ionic liquid

Abstract

The utility model provides a separation-enhanced cyclone reactor for ionic liquid alkylation, the whole cyclone reactor comprises a guide vane, a mixing area, a separation area and a conical tube sleeve, and the cyclone reactor is characterized in that the guide vane is a cyclone component; the mixing area is of a reactor column section structure and comprises a buffer cavity and a reaction cavity; the separation area comprises a conical section, and the lower part of the conical section is connected with an underflow pipe; the conical section of the separation area is provided with a tangential slot, and the tangential slot can discharge reaction products with relatively high density in time to ensure smooth separation of subsequent products; the upper part of the tangential seam is externally connected with a conical pipe sleeve; and the conical pipe sleeve is used for recycling reactants flowing out of the tangential seam. Through the structural design, reaction and separation in the cyclone are carried out at the same time, sufficient reaction, contact and mixing of ionic liquid and alkane are guaranteed, and reaction products are separated in time.

Description

Technical Field

[0001] The invention relates to the field of liquid-liquid heterogeneous mixing and separation equipment, and in particular to a cyclone reactor for enhanced separation of ionic liquid alkylation. Background Art

[0002] With increasingly stringent environmental protection requirements, the ionic liquid alkylation process has attracted widespread attention for its significant advantages of being green, environmentally friendly, non-toxic and harmless. In order to produce alkylate oil with high octane number, low sensitivity, and no sulfur, aromatics, or olefins, the ionic liquid alkylation technology has been developed. The ionic liquid catalytic alkylation reaction has a bright future but also brings us great challenges. At present, the alkylation reactor is still mainly based on traditional static mixers or stirred tanks, equipped with sedimentation separators. This process is relatively complicated, inefficient, and the sedimentation separation takes a long time, making it difficult to achieve efficient separation.

[0003] Chinese patent CN 112657439 A discloses a liquid-liquid heterogeneous cyclone reactor and reaction method based on multi-dimensional shearing action. This reactor uses the power of cyclone to disperse and mix two liquids together, thereby promoting the reaction. Multi-dimensional shearing action means that in the cyclone, the rotational motion of the liquid fluid generates shear forces in multiple directions, which helps mixing and mass transfer. However, the reaction time of this process is extremely short, and the two phases begin to separate before they have time to fully contact. The product entering the cone section is mixed with a large amount of reactants, which increases the cost of raw materials and makes subsequent separation of the mixture difficult.

[0004] Common reactors, such as stirred tank reactors, are usually difficult to achieve continuous operation and cannot achieve sustained and stable reaction conditions, which may lead to fluctuations in reaction conditions and reduced product purity. In addition, mixing of reactors may lead to mass transfer restrictions between reactants, which is not conducive to ionic liquid alkylation reactions. Cyclones are mainly used to separate reaction mixtures. Since the alkylate oil generated by the reaction cannot be completely separated, a cyclone reactor for ionic liquid alkylation with enhanced separation is designed. The reaction products with higher density can be discharged in time at the tangential slits of the cone section of the separation zone to ensure smooth separation of subsequent products. Summary of the invention

[0005] Based on the above objectives, the present invention provides a cyclone reactor for ionic liquid alkylation with enhanced separation, which realizes simultaneous reaction and separation in the cyclone through structural design, ensures that the ionic liquid (continuous phase) and C4 hydrocarbons (dispersed phase) are fully contacted and mixed, and the alkylate oil generated by the reaction is separated in time.

[0006] The technical scheme adopted by the present invention is as follows: a cyclone reactor for ionic liquid alkylation with enhanced separation, which as a whole comprises a guide vane, a mixing zone, a separation zone and a tapered pipe sleeve, wherein the guide vane is a cyclone-making component; the mixing zone is a column structure, comprising a buffer chamber and a reaction chamber; the buffer chamber comprises an upper buffer chamber and a lower buffer chamber, respectively provided with a heavy phase inlet and a light phase inlet; a plurality of tangential openings are opened on the inner wall of the light phase buffer zone and connected with the reaction chamber; the heavy phase buffer chamber is connected with the reaction chamber through a guide vane; an axially upward overflow pipe is arranged at the center of the reaction chamber; the lower part of the reaction chamber is connected with the separation zone; the separation zone comprises a cone section, which is connected with an underflow pipe below; the cone section is provided with a tangential slit, and the tangential slit is located at two-thirds of the area below the cone section; a total of four tangential slits are provided, which are distributed in a circumference; the slit direction is the same as the rotation direction of the guide vane and the rotation direction of the inlet; a tapered pipe sleeve is externally connected above the tangential slit; the tapered pipe sleeve is a cavity structure and covers the underflow pipe.

[0007] The working process of the cyclone reactor of the present invention is briefly described as follows:

[0008] The cyclone reactor of the present invention is used for ionic liquid alkylation reaction to produce high-octane alkylate oil. The heavy phase enters the mixing chamber through the heavy phase inlet, and the light phase enters the buffer chamber through the light phase inlet. A plurality of tangential inlets are arranged between the buffer chamber and the mixing chamber. Under the action of gravity, the light phase enters the mixing chamber and mixes with the heavy phase for reaction.

[0009] The products and catalyst after the reaction flow downward in a swirling manner along the reactor wall, and the separation of the products and catalyst is achieved in the separation zone. During the downward process, due to the different densities of the products after the reaction, under the action of the swirling flow, the alkylate oil with a smaller density moves upward along the axis, and the product with a larger density moves downward along the wall. At the tangential slit in the lower part of the cone section, the heavier components flow out from the tangential slit, and the alkylate oil continues to swirl downward to achieve further separation of the products and catalyst, thereby realizing an integrated process of reaction and separation.

[0010] Compared with the existing reactor, the present invention has the following advantages:

[0011] A tangential slit is provided in the lower part of the cone section, and a tangential slit is provided in the lower half to ensure sufficient contact reaction, so as to avoid separation due to failure of reaction under the influence of gravity. At the tangential slit, products with higher density are discharged in large quantities, which is beneficial to the separation of subsequent reactants, and further separation of reaction products and catalysts is achieved, thereby improving the overall separation efficiency and efficiently realizing reaction and separation integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings are described as follows:

[0013] Figure 1 It is a schematic diagram of the structure of the device of the present invention;

[0014] Figure 2It is a schematic diagram of the AA section;

[0015] Figure 3 is a cross-sectional view of a cyclone reactor;

[0016] Figure 4 This is the external view of the tangential slit;

[0017] In the figure, 1-heavy phase inlet; 2, 10-buffer chamber; 3-light phase inlet; 4-tangential hole; 5-overflow pipe; 6-tangential slit; 7-underflow pipe; 8-conical pipe sleeve; 9-conical section; 11-reaction chamber; 12-guide blade DETAILED DESCRIPTION

[0018] The present invention is further described in detail below with reference to the accompanying drawings.

[0019] Figure 1 The schematic diagram of the device structure of the present invention is shown in the figure. A cyclone reactor for alkylation of ionic liquids with enhanced separation comprises a guide vane, a mixing zone, a separation zone and a conical tube sleeve. The guide vane 12 is a cyclone-making component. The mixing zone is a column structure, including a buffer chamber 2, 10 and a reaction chamber 11. The buffer chamber 2, 10 is an upper and a lower buffer chamber 2, 10, respectively provided with a heavy phase and a light phase inlet 1, 3. The inner wall of the light phase buffer zone 3 is provided with a plurality of tangential openings connected to the reaction chamber. The heavy phase buffer chamber 10 and the reaction chamber 11 are connected to each other. They are connected through guide blades 12; an axially upward overflow pipe 5 is provided at the center of the reaction chamber 11; the reaction chamber 11 is connected to the separation zone below; the separation zone includes a cone section 9, which is connected to the bottom flow pipe 7 below; the cone section 9 is provided with a tangential slit 6, and the tangential slit 6 is located at the two-thirds area below the cone section 9; there are four in total, distributed in a circle; the slit direction is the same as the rotation direction of the guide blade 12 and the inlet rotation direction; the tangential slit 6 is externally connected to a conical pipe sleeve 8 above; the conical pipe sleeve 8 is a cavity structure and covers the bottom flow pipe 7.

[0020] like Figure 2 , 4 As shown, in the AA cross-sectional top view, there are four tangential slits 6 in the cross-sectional view of the cyclone reactor, which are distributed in a circle. In other examples, the number of tangential slits in the circle can also be set to other numbers, such as three or four.

[0021] like Figure 3 The figure shows a partial cross-sectional view of the guide blade 12, Figure 2 As shown, the tangential slit 6 of the cone section 9 has the same rotation direction as the side wall opening of the light phase buffer chamber 10 and the guide vane 12 .

[0022] The cyclone reactor for enhanced separation of ionic liquid alkylation of the present invention is used to realize the alkylation reaction of ionic liquid (heavy phase) and C4 hydrocarbon (light phase) and separate the reaction product and catalyst. The heavy phase is injected into the buffer chamber 2 through the inlet 1, and a cyclone is formed under the action of the tangential inflow. The light phase is injected into the buffer chamber 10 from the inlet 3. Under the action of the guide vane to enhance the cyclone, the two phases are deeply mixed, and the light phase is impacted by the heavy phase to form a large number of tiny droplets, thereby increasing the contact area between the two phases and making the reaction more complete.

[0023] Due to continuous feeding, the products and catalysts generated by the reaction fill the reaction chamber 11 and then flow into the area between the overflow pipe 5 and the cone section 9. The mixed liquid is initially separated from the product and the catalyst under the action of the swirl. The initially separated mixed liquid continues to flow downward. Due to the different densities of the mixed liquid, at the cone section 9, due to the centrifugal force, the catalyst with high density swirls downward on the outside of the cone section and reaches the lower part of the cone section 9. A large amount of catalyst flows out along the tangential slit 6 for recycling and further separation of the mixed liquid; the alkylate oil with low density moves toward the axis and is led out from the overflow pipe 5 to enter the subsequent production process.

Claims

1. A cyclone reactor for ionic liquid alkylation with enhanced separation, which comprises guide vanes, a mixing zone, a separation zone and a conical tube sleeve, characterized in that: The guide vane is a swirl-generating component; the mixing zone is a column-section structure, including a buffer chamber and a reaction chamber; the separation zone includes a cone section, which is connected to an underflow pipe; and the cone pipe sleeve is externally connected to the cone section.

2. The reactor according to claim 1, characterized in that: The guide vane is a swirl-generating component, and a heavy phase inlet is arranged above the guide vane.

3. The reactor according to claim 1, characterized in that: The mixing zone buffer chamber is composed of an upper buffer chamber and a lower buffer chamber, each of which is provided with a heavy phase inlet and a light phase inlet; the heavy phase buffer chamber is connected to the reaction chamber through a guide vane; and the inner wall of the light phase buffer chamber is provided with a plurality of tangential openings connected to the reaction chamber.

4. The reactor according to claim 1, characterized in that: An axially upward overflow pipe is provided in the center of the reaction chamber of the mixing zone; and the bottom of the reaction chamber is connected to the separation zone.

5. The reactor according to claim 1, characterized in that: The separation zone cone section is provided with a tangential slit, and a conical pipe sleeve is externally connected above the tangential slit; the tangential slit is located in the lower two-thirds area of ​​the cone section, and there are four tangential slits in total, which are distributed in a circle; the opening direction of the slit is the same as the rotation direction of the guide vane.

6. The reactor according to claim 1, characterized in that: The conical pipe sleeve is a hollow structure and covers the underflow pipe.

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