A reaction device and method for preparing N,N-dimethylacrylamide by cracking

Abstract

The invention relates to the technical field of mixed processing, and specifically discloses a reaction device and method for preparing N,N-dimethylacrylamide by cracking. The reaction device for preparing N,N-dimethylacrylamide by cracking comprises a reactor, wherein the reactor comprises an outer shell and an inner shell arranged in the outer shell, a mixing flow cavity is formed between the outer shell and the inner shell, and a spiral mixing flow plate is installed in the mixing flow cavity; the upper end of the mixing flow cavity is communicated with the inner shell, and a reflux hole communicated with the mixing flow cavity is opened on the side wall of the lower end of the inner shell; a lifting mixing flow piece and a driving piece for driving the mixing flow piece are arranged in the inner shell; the reactor in the invention realizes circulating mixing flow treatment of a cleavage solution by arranging the mixing flow cavity and the mixing flow piece, so that the cleavage solutions added at different periods can be fully mixed, and the uniformity and continuity of a continuous cleavage process are effectively improved, thereby improving the synthesis efficiency and yield of N,N-dimethylacrylamide.

Description

Technical Field

[0001] The invention relates to the technical field of mixed processing, and more specifically to a reaction device and method for preparing N,N-dimethylacrylamide by cracking. Background Art

[0002] N,N-dimethylacrylamide (DMAA) is a colorless, transparent liquid that easily undergoes polymerization reactions with various monomers and is widely used in adhesives, polymer resins, coatings, and other fields;

[0003] The continuous cracking method is a common method for preparing DMAA. A cracking solution formed by mixing 3-dimethylamino-N,N-dimethylacrylamide and a catalyst in a certain proportion is continuously added to the reactor, and a 705 inhibitor is added and the temperature is raised to 160°C for continuous cracking reaction.

[0004] During the cracking reaction, the existing reaction device has a sufficient circumferential mixing effect on the cracking solution, but the intervention effect on different levels of the cracking solution is limited. Since the cracking solution is added continuously, the cracking solution added at different times is prone to stratification in the reactor, resulting in inconsistent reaction progress of the cracking solution at different levels, which in turn affects the efficiency of the cracking reaction and the yield of the finished product. Summary of the invention

[0005] In order to overcome the above technical problems, the present invention provides a reaction device and method for preparing N,N-dimethylacrylamide by cracking.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] The present invention discloses a reaction device for preparing N,N-dimethylacrylamide by cracking, comprising a reactor, wherein the reactor comprises an outer shell and an inner liner arranged in the outer shell, a mixing flow cavity is formed between the outer shell and the inner liner, a spiral mixing flow plate is installed in the mixing flow cavity; the upper end of the mixing flow cavity is connected with the inner liner, and a reflux hole connected with the mixing flow cavity is opened on the side wall of the lower end of the inner liner;

[0008] The inner container is provided with a flow mixing element that can be raised and lowered and a driving element for driving the flow mixing element;

[0009] The flow mixing element includes a lifting plate adapted to the inner tank, a plurality of stepped through grooves are circumferentially provided on the lifting plate, a sliding groove is provided on the side wall of the stepped through groove, an elastic sealing piece is provided in the stepped through groove, one end of the elastic sealing piece is rotatably connected to one side of the stepped through groove, and the other end of the elastic sealing piece is movably embedded in the sliding groove; a plurality of connecting seats adapted to the driving member are circumferentially provided on the outer side of the lifting plate.

[0010] As a further solution of the present invention: a driving motor is installed on the top of the outer shell, the output end of the driving motor is connected to a stirring shaft extending into the inner tank, and a stirring blade is arranged at the lower end of the stirring shaft; a shaft sleeve is also arranged at the upper end of the outer shell, and a bearing adapted to the stirring shaft is installed in the shaft sleeve.

[0011] As a further solution of the present invention: a through hole is opened at the center of the lifting plate, an annular partition is arranged at the edge of the through hole, there is a gap between the annular partition and the stirring shaft, and the lower end of the annular partition is connected to a flexible shaft sealing ring adapted to the stirring shaft.

[0012] As a further solution of the present invention: the driving member includes:

[0013] The sleeves are provided in multiple groups and are circumferentially fixed on the corresponding connecting seats, and a limiting plate is provided on the upper end of the sleeves;

[0014] A mounting plate, which corresponds to the sleeve one by one and is fixed on the side wall of the inner container, and the sleeve vertically slides through the corresponding mounting plate;

[0015] The guide rod corresponds to the sleeve one by one and is fixed on the top wall of the inner container. A sliding cavity adapted to the guide rod is provided in the sleeve, and a return spring is movably sleeved on the guide rod.

[0016] As a further solution of the present invention: the driving member further includes:

[0017] A transmission shaft, which corresponds to the sleeve one by one and is rotatably mounted on the side wall of the inner container, the transmission shaft is mounted with a sector gear, and the sleeve is axially provided with a plurality of tooth grooves meshing with the sector gear;

[0018] A secondary bevel gear is installed at one end of each transmission shaft facing the stirring shaft, and a main bevel gear meshing with each secondary bevel gear is installed on the stirring shaft.

[0019] As a further solution of the present invention: an annular cavity is opened at the upper end of the inner liner, and an annular sealing plate is slidably embedded in the annular cavity. The annular sealing plate is used to seal the connecting port between the inner liner and the upper end of the mixing flow chamber. A sealing plate spring abutting against the annular sealing plate is also installed in the annular cavity, and a protrusion adapted to the connecting seat is provided at the lower end of the annular sealing plate.

[0020] As a further solution of the present invention: a jacket is arranged in the mixed flow chamber, a heating chamber isolated from the mixed flow chamber is arranged in the jacket, a water inlet pipe is connected to the lower end of the heating chamber, and a water outlet pipe is connected to the upper end of the heating chamber.

[0021] As a further solution of the present invention: a plurality of first heat-conducting strips are arranged in the heating chamber, second heat-conducting strips corresponding to the first heat-conducting strips are arranged in the inner tank, and a heat-conducting block is connected between the matching first heat-conducting strips and the second heat-conducting strips.

[0022] The present invention also discloses a method for preparing N,N-dimethylacrylamide by using the above-mentioned reaction device through cracking, comprising the following steps:

[0023] S1, continuously adding lysate and 705 inhibitor into the inner container;

[0024] S2, the driving member drives the lifting plate in the mixing member to rise along the inner tank, and the elastic sealing sheet closes the stepped through groove, thereby lifting the lysate in the inner tank upward until the lysate reaches the opening at the upper end of the mixing chamber and flows into the mixing chamber. The lysate flowing into the mixing chamber flows downward along the spiral mixing plate, so that the lysate is fully mixed until it reaches the lower end of the mixing chamber and flows back into the inner tank through the reflux hole;

[0025] S3, the driving member drives the lifting plate to descend and reset, and the elastic sealing sheet bounces upward under the hydraulic pressure of the lysing solution, so that one end of the elastic sealing sheet slides toward the other end along the slide groove, and the stepped groove channel is opened. The lysate below the lifting plate flows through the stepped groove to the lifting plate to rise, so as to capture the lysate;

[0026] S4, repeat steps S2-S3 until the reaction is completed.

[0027] Beneficial effects of the present invention:

[0028] The reactor of the present invention realizes the circulating mixed flow treatment of the lysate by arranging the mixing flow chamber and the mixing flow piece. First, the lifting plate in the mixing flow piece is driven by the driving piece to rise along the inner tank, and the elastic sealing piece closes the stepped through groove, so that the lysate in the inner tank is lifted upward until the lysate reaches the upper opening of the mixing flow chamber and flows into the mixing flow chamber. The lysate flowing into the mixing flow chamber spirally flows downward along the spiral mixing flow plate, so that the lysate is fully mixed, until it reaches the lower end of the mixing flow chamber and flows back into the inner tank through the reflux hole; then, the lifting plate is driven downward and reset by the driving piece, and the elastic sealing piece is bounced upward under the hydraulic action of the lysate, so that one end of the elastic sealing piece slides toward the other end along the slide groove, and the stepped through groove channel is opened, and the lysate below the lifting plate flows through the stepped through groove to the lifting plate to rise, so as to realize the capture of the lysate; and in such a cycle, the lysate added at different times can be fully mixed, and the uniformity and continuity of the continuous lysing process are effectively improved, thereby improving the synthesis efficiency and yield of N,N-dimethylacrylamide. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further described below in conjunction with the accompanying drawings.

[0030] Figure 1 It is a three-dimensional schematic diagram of a reaction kettle in a reaction device for preparing N,N-dimethylacrylamide by cracking according to the present invention;

[0031] Figure 2It is a cross-sectional view of a reaction kettle in a reaction device for preparing N,N-dimethylacrylamide by cracking according to the present invention;

[0032] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0033] Figure 4 for Figure 2 Enlarged view of point B in the middle;

[0034] Figure 5 This is a schematic structural diagram of a flow mixing component in a reaction device for preparing N,N-dimethylacrylamide by cracking according to the present invention;

[0035] Figure 6 This is a schematic structural diagram of another perspective of a flow mixing element in a reaction device for preparing N,N-dimethylacrylamide by cracking according to the present invention;

[0036] Figure 7 It is a schematic diagram of the state of the lifting plate in the reaction device for preparing N,N-dimethylacrylamide by cracking according to the present invention when it is descending;

[0037] Figure 8 It is a schematic diagram of the state of the lifting plate in the upward movement of a reaction device for preparing N,N-dimethylacrylamide by cracking of the present invention;

[0038] Fig. 9 It is a cross-sectional view from another perspective of a reaction kettle in a reaction device for preparing N,N-dimethylacrylamide by cracking according to the present invention;

[0039] Fig.10 for Fig. 9 Enlarged view of point C in the middle;

[0040] Fig.11 for Fig. 9 Enlarged view of point D in the middle;

[0041] Fig.12 for Fig. 9 Enlarged view of point E in the middle.

[0042] In the figure:

[0043] 100, reactor; 101, feed pipe; 102, discharge pipe; 103, pressure gauge; 104, bushing; 105, bearing; 110, housing; 120, liner; 121, reflux hole; 122, annular cavity; 123, annular sealing plate; 124, sealing plate spring; 125, raised portion; 130, mixing chamber; 140, spiral mixing plate;

[0044] 200, driving motor; 210, stirring shaft; 220, stirring blade;

[0045] 300, flow mixing piece; 310, lifting plate; 320, annular partition; 330, stepped through groove; 331, slide groove; 340, elastic sealing piece; 350, flexible shaft sealing ring; 360, connecting seat; 361, avoidance groove;

[0046] 400, driving member; 410, sleeve; 411, tooth groove; 412, sliding cavity; 420, mounting plate; 430, limit plate; 440, guide rod; 450, return spring; 460, transmission shaft; 470, auxiliary bevel gear; 480, main bevel gear; 490, sector gear;

[0047] 500, jacket; 501, heating chamber; 510, water inlet pipe; 520, water outlet pipe; 530, first heat-conducting strip; 540, heat-conducting block; 550, second heat-conducting strip. DETAILED DESCRIPTION

[0048] The subject matter described herein will now be discussed with reference to example embodiments. It should be understood that the discussion of these embodiments is only to enable those skilled in the art to better understand and implement the subject matter described herein, and the functions and arrangements of the elements discussed may be changed without departing from the scope of protection of the contents of this specification. Each example may omit, replace or add various processes or components as needed. In addition, the features described relative to some examples may also be combined in other examples.

[0049] See also Figure 1 and Figure 2 The present invention discloses a reaction device for preparing N,N-dimethylacrylamide by cracking, comprising a reactor 100, wherein the reactor 100 comprises an outer shell 110 and an inner liner 120 disposed in the outer shell 110, wherein a mixing chamber 130 is formed between the outer shell 110 and the inner liner 120, wherein a spiral mixing plate 140 is installed in the mixing chamber 130; wherein the upper end of the mixing chamber 130 is connected to the inner liner 120, and a reflux hole 121 connected to the mixing chamber 130 is provided on the side wall of the lower end of the inner liner 120;

[0050] The inner container 120 is provided with a flow mixing element 300 that can be raised and lowered and a driving element 400 for driving the flow mixing element 300;

[0051] See also Figure 2 and Figure 3The mixing element 300 includes a lifting plate 310 adapted to the inner liner 120, and a plurality of stepped through grooves 330 are circumferentially provided on the lifting plate 310, and a slide groove 331 is provided on the side wall of the stepped through groove 330, and an elastic sealing piece 340 is provided in the stepped through groove 330, and one end of the elastic sealing piece 340 is rotatably connected to one side of the stepped through groove 330, and the other end of the elastic sealing piece 340 is movably embedded in the slide groove 331; a plurality of connecting seats 360 adapted to the driving member 400 are circumferentially provided on the outer side of the lifting plate 310;

[0052] Specifically, the lysate and the 705 inhibitor are respectively added to the inner liner 120 of the reactor 100 through the feed pipe 101 to start the lysate reaction. During the lysate reaction and the subsequent continuous replenishment of the lysate, the lifting plate 310 in the mixing member 300 is driven by the driving member 400 to periodically lift and lower along the inner liner 120. When the lifting plate 310 rises, the elastic sealing sheet 340 closes the stepped through groove 330, thereby lifting the lysate in the inner liner 120 upward until the lysate reaches the upper opening of the mixing chamber 130, so that the lysate above the lifting plate 310 flows into the mixing chamber 130, and the lysate flowing into the mixing chamber 130 spirally flows downward along the spiral mixing plate 140, so that the lysate is fully mixed until it reaches the lower end of the mixing chamber 130 and flows back to the inner liner 120 through the reflux hole 121;

[0053] Then the driving member 400 drives the lifting plate 310 to descend and reset again, and the elastic sealing sheet 340 bounces upward under the hydraulic pressure of the lysing solution, so that one end of the elastic sealing sheet 340 slides toward the other end along the slide groove 331, thereby opening the channel of the stepped groove 330, and the lysing solution under the lifting plate 310 flows through the stepped groove 330 to the lifting plate 310 to rise, so as to achieve the capture of the lysing solution;

[0054] When the lifting plate 310 rises again, the elastic sealing sheet 340 rebounds downward and resets under the hydraulic pressure of the lysing solution above, thereby closing the stepped groove 330 again to carry out a new round of lysing solution lifting. This reciprocating process can achieve a circulating mixed flow treatment of the lysing solution, so that the lysing solution added at different times can be fully mixed, effectively improving the uniformity and continuity of the continuous lysing process, and thereby improving the synthesis efficiency and yield of N,N-dimethylacrylamide.

[0055] See also Figure 1The upper end of the reactor 100 is provided with a plurality of feed pipes 101 connected to the inner tank 120, and the reaction raw materials, catalysts and 705 inhibitors can be added into the inner tank 120 through the corresponding feed pipes 101. The lower end of the reactor 100 is connected with a discharge pipe 102 connected to the inner tank 120, and the cracked liquid obtained after continuous cracking is discharged from the discharge pipe 102; the reactor 100 is also equipped with a pressure gauge 103 for detecting the air pressure in the inner tank 120, so as to understand whether the environmental pressure of the continuous cracking reaction meets the standard.

[0056] For further information, see Figure 2 A driving motor 200 is installed on the top of the housing 110, and the output end of the driving motor 200 is connected to a stirring shaft 210 extending into the inner pot 120, and a stirring blade 220 is arranged at the lower end of the stirring shaft 210; a shaft sleeve 104 is also arranged at the upper end of the housing 110, and a bearing 105 adapted to the stirring shaft 210 is installed in the shaft sleeve 104;

[0057] Specifically, the stirring shaft 210 is driven to rotate by the driving motor 200 , thereby driving the stirring blade 220 at the lower end of the stirring shaft 210 to rotate, so as to circumferentially stir and mix the lysate in the inner container 120 .

[0058] See also Figure 5 and Figure 6 In order to prevent the stirring shaft 210 from interfering with the lifting process of the lifting plate 310, a through hole is opened at the center of the lifting plate 310, and an annular partition 320 is arranged at the edge of the through hole. There is a gap between the annular partition 320 and the stirring shaft 210, and the lower end of the annular partition 320 is connected to a flexible shaft sealing ring 350 adapted to the stirring shaft 210;

[0059] See also Figure 7 When the lifting plate 310 moves downward, the flexible shaft sealing ring 350 is pushed upward by the lysate below the lifting plate 310, so that the flexible shaft sealing ring 350 contracts radially to seal and wrap the flexible shaft sealing ring 350, and the lysate below the lifting plate 310 is forced to open the elastic sealing sheet 340 and flow into the upper part of the lifting plate 310 from the stepped groove 330, so as to capture the lysate;

[0060] See also Figure 8 When the lifting plate 310 moves upward, since the elastic sealing piece 340 cannot be opened in the reverse direction, the flexible shaft sealing ring 350 expands radially and separates from the stirring shaft 210 under the impact of the lysate above the lifting plate 310, so that the gap between the annular partition 320 and the stirring shaft 210 is connected, and part of the lysate above the lifting plate 310 can flow back to the bottom of the lifting plate 310 through the gap channel during the rising process of the lifting plate 310. On the one hand, it can prevent the lysate above the lifting plate 310 from accumulating, and on the other hand, it can promote the full fusion of lysate at different levels.

[0061] See also Figure 2 and Figure 4 The driving member 400 includes a sleeve 410, a mounting plate 420, a guide rod 440 and a transmission shaft 460; the sleeve 410 is provided with multiple groups and is circumferentially fixed on the corresponding connecting seat 360, and a limit plate 430 is provided on the upper end of the sleeve 410; the mounting plate 420 corresponds to the sleeve 410 one by one and is fixed on the side wall of the inner tank 120, and the sleeve 410 vertically slides through the corresponding mounting plate 420;

[0062] See also Fig. 9 and Fig.10 The guide rod 440 corresponds to the sleeve 410 one by one and is fixed on the top wall of the inner container 120. The sleeve 410 is provided with a sliding cavity 412 adapted to the guide rod 440. A return spring 450 is movably sleeved on the guide rod 440.

[0063] The transmission shaft 460 corresponds to the sleeve 410 one by one and is rotatably mounted on the side wall of the inner container 120. The transmission shaft 460 is mounted with a sector gear 490. The sleeve 410 is axially provided with a plurality of tooth grooves 411 meshing with the sector gear 490. A secondary bevel gear 470 is mounted on one end of each transmission shaft 460 facing the stirring shaft 210. A main bevel gear 480 meshing with each secondary bevel gear 470 is mounted on the stirring shaft 210.

[0064] Specifically, when the driving motor 200 drives the stirring shaft 210 to rotate, the main bevel gear 480 and the auxiliary bevel gears 470 are meshed and driven to drive the transmission shafts 460 to rotate synchronously, and then the fan gears 490 are meshed and driven with the tooth grooves 411 on the corresponding sleeves 410 to drive the sleeves 410 to rise synchronously. At the same time, the guide rod 440 is inserted into the sliding cavity 412 of the sleeve 410, and the return spring 450 is compressed to realize the lifting of the lifting plate 310.

[0065] As the lifting plate 310 is continuously lifted, the gear teeth on the sector gear 490 gradually disengage from the tooth grooves 411 on the sleeve 410. When the lifting plate 310 completely reaches the upper opening of the mixing chamber 130 and discharges the lysate into the mixing chamber 130, all the gear teeth on the sector gear 490 disengage from the tooth grooves 411 on the sleeve 410. Then, the sleeve 410 can slide downward under the elastic force of the reset spring 450, thereby driving the lifting plate 310 to reset downward.

[0066] Next, the gear teeth on the sector gear 490 mesh with the tooth groove 411 again, thereby driving the lifting plate 310 to rise again.

[0067] It is worth noting that during the ascent of the lifting plate 310, the sleeve 410 is lifted by the fan gear 490, so that the ascent process of the lifting plate 310 is relatively smooth, avoiding the lysate above it from shaking violently; during the downward reset process of the lifting plate 310, the sleeve 410 is driven by the elastic force of the reset spring 450, so that the lifting plate 310 is quickly reset, and at the same time, the lifting plate 310 is used to impact the lysate below, further promoting the fusion of lysate at different levels.

[0068] See also Fig. 9 and Fig.11 , considering that when the lifting plate 310 is reset downward and impacts the lysate in the inner tank 120, it is easy to cause the lysate to splash, in order to prevent the splashing lysate from interfering with the lysate in the mixing chamber 130, an annular cavity 122 is provided at the upper end of the inner tank 120, and an annular sealing plate 123 is slidably embedded in the annular cavity 122. The annular sealing plate 123 is used to block the communication port between the inner tank 120 and the upper end of the mixing chamber 130, and a sealing plate spring 124 abutting against the annular sealing plate 123 is also installed in the annular cavity 122, and a protrusion 125 adapted to the connecting seat 360 is provided at the lower end of the annular sealing plate 123;

[0069] Specifically, when the lifting plate 310 rises, the connecting seat 360 on the lifting plate 310 abuts against the protrusion 125 on the annular sealing plate 123, thereby pushing the annular sealing plate 123 upward, so that the annular sealing plate 123 is retracted into the annular cavity 122, the sealing plate spring 124 is compressed, and the communication port between the inner liner 120 and the upper end of the mixing chamber 130 is gradually opened, so that the lysate above the lifting plate 310 can smoothly flow into the mixing chamber 130;

[0070] When the lifting plate 310 descends, the annular sealing plate 123 can gradually pop out and reset from the annular cavity 122 under the elastic force of the sealing plate spring 124 until the connecting seat 360 and the protrusion 125 are completely separated. The annular sealing plate 123 completely blocks the connecting port between the inner liner 120 and the upper end of the mixing chamber 130, thereby preventing the splashing liquid generated by the lifting plate 310 impacting the lysis liquid from entering the mixing chamber 130.

[0071] For further information, see Fig. 9 and Fig.12 Considering that the temperature of the lysate in the reactor 100 will drop during the continuous replenishment of the lysate, in order to maintain a stable reaction temperature for the continuous lysate reaction, the lysate needs to be heated. For this purpose, a jacket 500 is provided in the mixing chamber 130, and a heating chamber 501 isolated from the mixing chamber 130 is provided in the jacket 500. The lower end of the heating chamber 501 is connected to a water inlet pipe 510, and the upper end of the heating chamber 501 is connected to a water outlet pipe 520;

[0072] Specifically, external hot water is introduced into the heating chamber 501 in the jacket 500 through the water inlet pipe 510. The hot water in the heating chamber 501 can heat the lysate flowing in the mixing chamber 130 and the spiral mixing plate 140. The lysate in the inner tank 120 can also be heated by heat conduction. The water after absorbing the heat flows out from the upper water outlet pipe 520.

[0073] It should be noted that the water inlet pipe 510 is arranged at the lower end of the heating chamber 501, and the water outlet pipe 520 is arranged at the upper end of the heating chamber 501, so that the hot water flows from bottom to top, and its flow direction is opposite to the flow direction of the lysis liquid from top to bottom on the spiral mixing plate 140, thereby increasing the heat exchange path between the hot water and the lysis liquid in the mixing chamber 130, and improving the heating effect.

[0074] Also, see Fig. 9 and Fig.12 For heating the lysate in the inner tank 120, a plurality of first heat-conducting strips 530 are arranged in the heating chamber 501, and second heat-conducting strips 550 corresponding to the first heat-conducting strips 530 are arranged in the inner tank 120, and a heat-conducting block 540 is connected between the matching first heat-conducting strips 530 and the second heat-conducting strips 550;

[0075] The heat of the hot water in the heating chamber 501 can be conducted to the second heat-conducting bar 550 in the inner tank 120 through the first heat-conducting bar 530 and the heat-conducting block 540 , thereby improving the heating efficiency of the lysis solution in the inner tank 120 .

[0076] Accordingly, see Figure 5 and Figure 6 In order to prevent the second heat-conducting bar 550 from interfering with the lifting and lowering of the lifting plate 310 , an avoidance groove 361 adapted to the second heat-conducting bar 550 is opened in the connecting seat 360 .

[0077] In another embodiment, a method for preparing N,N-dimethylacrylamide by using the above-mentioned reaction device for cracking is also provided, comprising the following steps:

[0078] S1, continuously adding lysate and 705 polymerization inhibitor into the inner container 120;

[0079] S2, the driving member 400 drives the lifting plate 310 in the mixing member 300 to rise along the inner liner 120, and the elastic sealing sheet 340 closes the stepped through groove 330, thereby lifting the lysate in the inner liner 120 upward until the lysate reaches the upper opening of the mixing chamber 130 and flows into the mixing chamber 130, and the lysate flowing into the mixing chamber 130 flows downward along the spiral mixing plate 140, so that the lysate is fully mixed until it reaches the lower end of the mixing chamber 130 and flows back into the inner liner 120 through the reflux hole 121;

[0080] S3, the driving member 400 drives the lifting plate 310 to descend and reset, and the elastic sealing sheet 340 bounces upward under the hydraulic pressure of the lysing solution, so that one end of the elastic sealing sheet 340 slides toward the other end along the slide groove 331, and the stepped through groove 330 is opened. The lysate below the lifting plate 310 flows through the stepped through groove 330 to the lifting plate 310 to rise, so as to capture the lysate;

[0081] S4, repeat steps S2-S3 until the reaction is completed.

[0082] The specific implementation methods of this embodiment are described above, but this embodiment is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Ordinary technicians in this field can also make many forms inspired by this embodiment, all of which are within the protection of this embodiment.

Claims

1. A reaction device for preparing N,N-dimethylacrylamide by cracking, comprising a reaction kettle (100), characterized in that: The reaction kettle (100) comprises an outer shell (110) and an inner liner (120) arranged in the outer shell (110); a mixing chamber (130) is formed between the outer shell (110) and the inner liner (120); a spiral mixing plate (140) is installed in the mixing chamber (130); the upper end of the mixing chamber (130) is in communication with the inner liner (120); and a reflux hole (121) in communication with the mixing chamber (130) is provided on a side wall at the lower end of the inner liner (120); The inner container (120) is provided with a flow mixing element (300) that can be raised and lowered and a driving element (400) for driving the flow mixing element (300); The flow mixing element (300) comprises a lifting plate (310) adapted to the inner container (120); a plurality of stepped through grooves (330) are circumferentially provided on the upper surface of the lifting plate (310); a sliding groove (331) is provided on the side wall of the stepped through groove (330); an elastic sealing sheet (340) is provided in the stepped through groove (330); one end of the elastic sealing sheet (340) is rotatably connected to one side of the stepped through groove (330); and the other end of the elastic sealing sheet (340) is movably embedded in the sliding groove (331); a plurality of connecting seats (360) adapted to the driving element (400) are circumferentially provided on the outer side of the lifting plate (310); A driving motor (200) is installed on the top of the housing (110); the output end of the driving motor (200) is connected to a stirring shaft (210) extending into the inner container (120); a stirring blade (220) is provided at the lower end of the stirring shaft (210); a shaft sleeve (104) is also provided at the upper end of the housing (110); a bearing (105) adapted to the stirring shaft (210) is installed in the shaft sleeve (104); A through hole is provided at the center of the lifting plate (310); an annular baffle (320) is provided at the edge of the through hole; a gap exists between the annular baffle (320) and the stirring shaft (210); a flexible shaft sealing ring (350) adapted to the stirring shaft (210) is connected to the lower end of the annular baffle (320); The driving member (400) comprises: A plurality of sleeves (410) are provided and circumferentially fixed on corresponding connecting seats (360); a limiting plate (430) is provided on the upper end of the sleeve (410); A mounting plate (420) corresponding one-to-one to the sleeve (410) and fixed on the side wall of the inner container (120), wherein the sleeve (410) vertically slides through the corresponding mounting plate (420); A guide rod (440) corresponding to the sleeve (410) and fixed on the top wall of the inner container (120); a sliding cavity (412) adapted to the guide rod (440) is provided in the sleeve (410); a return spring (450) is movably sleeved on the guide rod (440); The driving member (400) further comprises: A transmission shaft (460) corresponding one-to-one to the sleeve (410) and rotatably mounted on the side wall of the inner container (120); a sector gear (490) is mounted on the transmission shaft (460); and a plurality of tooth grooves (411) meshing with the sector gear (490) are axially arranged on the sleeve (410); A secondary bevel gear (470) is mounted on one end of each transmission shaft (460) facing the stirring shaft (210), and a main bevel gear (480) meshing with each secondary bevel gear (470) is mounted on the stirring shaft (210); An annular cavity (122) is provided at the upper end of the inner liner (120), and an annular sealing plate (123) is slidably embedded in the annular cavity (122). The annular sealing plate (123) is used to seal the communication port between the inner liner (120) and the upper end of the mixing chamber (130). A sealing plate spring (124) abutting against the annular sealing plate (123) is also installed in the annular cavity (122). A protrusion (125) adapted to the connecting seat (360) is provided at the lower end of the annular sealing plate (123).

2. The reaction device for preparing N,N-dimethylacrylamide by cracking according to claim 1, characterized in that: A jacket (500) is provided in the mixing chamber (130), a heating chamber (501) isolated from the mixing chamber (130) is provided in the jacket (500), a water inlet pipe (510) is connected to the lower end of the heating chamber (501), and a water outlet pipe (520) is connected to the upper end of the heating chamber (501).

3. The reaction device for preparing N,N-dimethylacrylamide by cracking according to claim 2, characterized in that: A plurality of first heat-conducting strips (530) are arranged in the heating chamber (501), second heat-conducting strips (550) corresponding to the first heat-conducting strips (530) are arranged in the inner pot (120), and a heat-conducting block (540) is connected between the matching first heat-conducting strips (530) and the second heat-conducting strips (550).

4. A method for preparing N,N-dimethylacrylamide by cracking using the reaction device according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1, continuously adding lysate and 705 polymerization inhibitor into the inner container (120); S2, the driving member (400) drives the lifting plate (310) in the flow mixing member (300) to rise along the inner liner (120), and the elastic sealing sheet (340) closes the stepped through groove (330), thereby lifting the lysate in the inner liner (120) upward until the lysate reaches the upper opening of the flow mixing chamber (130) and flows into the flow mixing chamber (130), and the lysate flowing into the flow mixing chamber (130) flows downward in a spiral along the spiral flow mixing plate (140), so that the lysate is fully mixed, until the lysate reaches the lower end of the flow mixing chamber (130) and flows back into the inner liner (120) through the reflux hole (121); S3, the driving member (400) drives the lifting plate (310) to descend and reset, and the elastic sealing sheet (340) bounces upward under the hydraulic pressure of the lysing liquid, so that one end of the elastic sealing sheet (340) slides toward the other end along the slide groove (331), and the channel of the stepped through groove (330) is opened, and the lysing liquid under the lifting plate (310) flows through the stepped through groove (330) to the lifting plate (310) to rise, so as to achieve the capture of the lysing liquid; S4, repeat steps S2-S3 until the reaction is completed.

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