CN103463829B - The rotary packed bed mass transfer of the reverse shearing of air-flow and consersion unit - Google Patents

Abstract

The invention belongs to the technical field of mass transfer reaction equipment, and in particular relates to a mass transfer and reaction equipment of an airflow reverse shear rotating packed bed, which solves the problems existing in the gas phase mass transfer of the existing high gravity equipment. It includes the main body of the rotating bed, the equipment support and the transmission device. The main body of the rotating bed includes two parts: the air collection chamber and the main chamber. The main chamber is equipped with a filling rotor that can rotate at high speed. The upper part of the main chamber is connected to the intake pipe. The bottom of the chamber is connected to the discharge pipe, the center of the filling rotor is provided with a liquid distributor, the liquid distributor is connected to the liquid inlet pipe, the top of the gas collection chamber is connected to the exhaust pipe, and the opening on the top of the filling rotor communicates with the gas collection chamber. Beneficial effects of the present invention: the shear stress on the fluid can be increased, the filler can transfer more momentum to the internal fluid, promote the separation of the gas-liquid boundary layer, intensify the degree of turbulence, and accelerate the update rate of the gas-liquid interface, thereby achieving a strengthened gas phase The purpose of mass transfer; improve the operation stability, more suitable for large flux occasions; the gas collection chamber effectively suppresses the impact of entrainment and liquid flooding on the operation balance.

Description

Gas flow reverse shear rotary packed bed mass transfer and reaction equipment

technical field

The invention belongs to the technical field of chemical industry, petrochemical industry, and environmental protection mass transfer reaction equipment, and specifically relates to a mass transfer and reaction equipment of air flow reverse shearing rotating packed bed, which can be used for intensifying the mass transfer process of gas film control such as rectification and absorption .

Background technique

Hypergravity technology is a breakthrough technology developed in the 1980s to strengthen the multiphase transfer and reaction process. In the gravity environment, the liquid is sheared and atomized by the filler, the contact area between the phases increases, and the rapid renewal of the surface leads to the great enhancement of the mass transfer, heat transfer and reaction process controlled by the liquid phase. At present, it is mainly used in desulfurization, decarburization, dust removal and nano-material preparation.

At present, the internal rotors of the commonly used rotating packed beds are of integral structure, that is, the packing in the rotor is driven by a single rotating shaft to rotate. The first patent on the high-gravity rotating bed was proposed by the British Imperial Chemical Industries (ICI) in 1979. Patent No. It is EP0002568, and the patents published successively at home and abroad also basically continue this rotor structure. In 2001, Sandilya et al. found that the gas-phase mass transfer process in a rotating packed bed has a lower mass transfer coefficient than that in a packed tower. The transfer rate is very small, the gas phase interface cannot be updated quickly, and the uneven distribution of the liquid phase in the packing will further reduce the mass transfer rate. In 2004, the research of DPRao et al. showed that the liquid phase mass transfer process was mainly enhanced in the high gravity rotating bed, and the use of high specific surface area fillers under the high gravity field was the main reason, while the gas phase mass transfer coefficient was comparable to that of traditional packed towers. . In 2005, Chandra A proposed the Rotating Packed bed with Split Packing (SP-RPB) for the first time, which divided the monolithic rotor packing in the ordinary rotating packed bed into several nested packing rings. Tangential slip velocity in rotating packing. In 2006, Reddy et al. studied the mass transfer performance of SP-RPB, and the results showed that the volumetric mass transfer coefficient of the gas phase and liquid phase of the device was nearly 2 orders of magnitude higher than that of ordinary rotating beds. Agarwal et al. did a series of rectification and absorption experiments with SP-RPB, and the results showed that SP-RPB is especially suitable for the mass transfer process with enhanced gas phase resistance control. However, SP-RPB also has some problems, such as: the rotor center or the part near the center has a small rotation radius, it is difficult for the gas to obtain a large tangential velocity through the high-speed rotation of the filler, the degree of gas phase turbulence is insufficient, and the radial distribution is uneven , The utilization rate of the filler is low; the filler is directly fixed on the upper and lower turntables with foam metal, which is not easy to replace, and it only depends on the mechanical strength of the foam metal itself during work, so it is difficult to apply to the occasions of atmospheric and liquid flux.

Contents of the invention

In order to solve the problems existing in the gas-phase mass transfer of the existing high-gravity equipment, the present invention provides a reverse-shear rotating packed bed mass transfer and reaction equipment, which can be applied to occasions with large throughput and high processing requirements.

The present invention adopts following technical scheme to realize:

A mass transfer and reaction equipment for airflow reverse shear rotating packed bed, including rotating bed main body, equipment bracket and transmission device. The rotating bed main body includes upper and lower parts: gas collection chamber and main chamber. The upper part of the main chamber is connected to the intake pipe, the bottom of the main chamber is connected to the discharge pipe, the center of the filling rotor is equipped with a liquid distributor, the liquid distributor is connected to the liquid inlet pipe, the top of the gas collection chamber is connected to the exhaust pipe, and the top of the filling rotor is opened. The hole communicates with the gas collection chamber.

The packing rotor includes an upper turntable and a lower turntable which rotate independently, respectively. The bottom of the upper turntable and the top of the lower turntable are respectively equipped with a number of concentric ring-shaped packing supports. The packing support is filled with filler to form a packing ring. The rings are nested with each other, and there is a gap between adjacent packing rings. The top of the upper turntable is connected to the solid shaft, the bottom of the lower turntable is connected to the hollow shaft, the top of the hollow shaft is connected to the liquid distributor, and the bottom of the hollow shaft is connected to the liquid inlet pipe.

The bottom of the upper turntable and the top of the lower turntable are respectively provided with a number of concentric annular grooves, the packing ring is fixed in the groove, the free end of the packing ring extends into the groove of another turntable, and stays with the bottom of the other turntable. There are gaps.

The main chamber and the gas collection chamber are separated by a partition. A hole is opened in the center of the partition and a cylindrical structure is set. The solid shaft passes through the hole and is connected to the upper turntable.

A sealing structure is provided at the part where the opening on the top of the packing rotor communicates with the gas collection chamber. The sealing structure includes an upper sealing cover and a lower sealing cover arranged up and down. The upper sealing cover is sleeved on the cylindrical structure, and the lower sealing Turntable connection, several fan-shaped holes are evenly distributed in the center of the lower sealing cover, labyrinth rings are provided on the upper sealing cover and the lower sealing cover, the labyrinth rings of the upper sealing cover and the lower sealing cover are embedded together, and the outermost ring of the labyrinth ring is provided with an oil seal Felt circle.

The packing support is a cylindrical stainless steel ring with densely distributed holes in the circumferential direction. Several physical resistance parts are arranged on the outer edge of the packing support. The physical resistance parts are metal sheet-like protrusions and are installed vertically on The outer edge of the filler support, the arc or table shape of the section of the metal sheet-like protrusion.

A swivel joint is used to connect the hollow shaft and the liquid inlet pipe.

The air inlet pipe passes through the air collection chamber and connects with the main chamber.

The transmission device comprises a hollow shaft, a solid shaft, a pulley, a belt and a motor. The outer ends of the hollow shaft and the solid shaft are equipped with passive pulleys, which are connected with the motor through the belt.

The whole rotating bed body and the motor are installed on the equipment bracket, the rotating bed body is fixed at the center of the bracket through the card seat, the motor is fixed in the T-shaped slot at the upper and lower parts of the bracket, and the motor fixing bolts can slide in the T-shaped slot.

Compared with the prior art, the beneficial effects of the present invention are: 1. The shape resistance parts constructed on the edge of each ring packing layer can increase the shear stress on the fluid, and the packing will transfer more momentum to the internal fluid, promoting the gas-liquid The boundary layer is separated, the degree of turbulence is intensified, and the update rate of the gas-liquid interface is accelerated, so as to achieve the purpose of strengthening the mass transfer of the gas phase; 2. The use of porous stainless steel packing support components improves the operation stability and is more suitable for large-flux occasions, and The packing used in the rotary bed is easy to replace; 3. The distribution of gas-liquid fluid in the packing is more uniform, and the degree of microscopic mixing is improved. 4. The gas comes out from the center of the rotor and enters the gas collection chamber first, and then is discharged through the exhaust pipe. The gas collection chamber can accommodate a certain amount of liquid blown out by the gas, effectively suppressing the impact of entrainment and liquid flooding on the operating balance.

Description of drawings

Fig. 1 is the schematic diagram of the main body of the airflow reverse shear rotating packed bed equipment of the present invention;

Fig. 2 is a schematic structural view of the body resistance member of the present invention;

Fig. 3 is another structural schematic diagram of the body resistance member of the present invention;

Fig. 4 is the assembly schematic diagram of the packing ring on the upper and lower turntables of the present invention;

Fig. 5 is a schematic diagram of the internal structure of the present invention;

In the figure: 1-intake pipe, 2-exhaust pipe, 3-rotary bed body, 4-drainage pipe, 5-rotary joint, 6-belt, 7-equipment bracket, 8-T-slot, 9-motor, 10-belt pulley, 11-main chamber, 12-packing ring, 13-liquid distributor, 14-hollow shaft, 15-bearing, 16-shaft sleeve Ⅰ, 17-lower turntable, 18-upper turntable, 19-upper seal Cover, 20-gas collection chamber, 21-shaft sleeve II, 22-solid shaft, 23-oil seal, 24-lower sealing cover, 25-partition plate.

Detailed ways

The specific embodiment of the present invention will be further described in conjunction with the accompanying drawings.

Air flow reverse shearing rotating packed bed mass transfer and reaction equipment mainly includes rotating bed main body, equipment support and transmission device. The main body of the rotary bed is divided into two parts, the upper air collection chamber and the lower main chamber. The air collection chamber and the main chamber are separated by a partition; the filling rotor is installed in the main chamber and consists of upper and lower turntables that can rotate independently , the distance between the upper and lower turntables is 30mm, each of the turntables is equipped with concentric ring-shaped packing supports, and the interior is filled with wire mesh packing. The packing and packing supports on the upper and lower turntables form mutually nested packing rings. The thickness of the packing rings is 16mm. The distance between adjacent packing layers is 8mm, and the outer edge of the packing ring is equipped with physical resistance parts; the upper turntable is connected with the top solid shaft, and the lower turntable is connected with the bottom hollow shaft; the air inlet pipe enters the main chamber through the air collection chamber, and the liquid enters through the hollow shaft The liquid distributor in the center of the rotor, the exhaust pipe is set on the top of the gas collection chamber, and the liquid discharge pipe is set on the bottom of the bed. The opening on the top of the filler rotor communicates with the air collection chamber.

One end of the packing ring is fixed in the groove opened by the upper and lower turntables through the packing support. The depth of the groove is 10mm. The free end of the packing ring extends into the other turntable by 6mm, leaving a gap with the bottom of the other turntable. To the dynamic sealing effect. The packing support is a cylindrical stainless steel ring with dense openings in the circumferential direction as the fluid channel.

A sealing structure is provided at the part where the opening on the top of the filler rotor communicates with the gas collection chamber. The sealing structure is composed of an upper sealing cover and a lower sealing cover. The sealing cover is a labyrinth ring with a thickness of 4 mm and a depth of 30 mm. Embedded together, the outermost ring of the labyrinth seal is provided with an oil seal felt ring to strengthen the sealing effect. The main chamber and the air collection chamber are separated by a partition. A hole is opened in the center of the partition and a cylindrical structure is set. The solid shaft and its upper shaft sleeve II pass through the cylindrical structure to connect with the upper turntable. The upper sealing cover is sleeved on the cylindrical structure. , the lower sealing cover is connected with the upper turntable, and a plurality of fan-shaped holes are uniformly arranged in the center of the lower sealing cover. The central opening of the upper and lower sealing covers serves as a gas passage at the same time.

The physical resistance member is a metal sheet-like protrusion, which is installed vertically on the outer edge of the packing support. The cross-section of the metal sheet-like protrusion is arc-shaped or table-shaped. When the rotating packing bed is working, the upper and lower turntables rotate in reverse at high speed. The airflow in the gap causes extremely strong turbulence, and the gas phase turbulence intensifies.

The liquid distributor is a stainless steel tube with holes in the circumferential direction. The size of the holes and the number of holes are determined by the process conditions such as flow rate and liquid velocity. The liquid distributor is connected to the lower turntable through the thread at the end of the pipe.

In the transmission device, the shaft seal close to the rotor is sealed with a TC skeleton oil seal, and the outer end of the shaft is sealed with an oil seal felt ring; the joint of the bed shell is sealed with a polyurethane rubber ring.

The hollow shaft and the liquid inlet pipe are connected through a rotary joint, and the rotary joint is required to have a working strength of ￡1500r/min and certain corrosion resistance.

The transmission device is composed of shafts, bearings, bearing sleeves, pulleys, belts and motors. The upper main shaft is a solid shaft, and the lower main shaft is a hollow shaft with an inner diameter of 16 mm. Because the upper and lower turntables have high requirements for cooperation, the bearings are deep grooves. The combination of ball bearing and thrust bearing can prevent the small displacement of the rotating shaft in the axial direction. The shaft and bearing are installed in the bearing sleeve, and the shaft sleeve has a hole for adding lubricating oil. The upper end of the shaft is equipped with a passive pulley, which is connected with the motor through a belt, and the motor speed is adjusted by a frequency converter. The whole bed body and motor are installed on the equipment bracket. The bed body is fixed at the center of the bracket with a card holder. The motor is fixed in the T-shaped slot on the upper and lower parts of the bracket. The motor fixing bolts can slide in the T-shaped slot to adjust the motor and the motor. The distance between the beds.

In the working state, the liquid is transported by the hollow shaft to the liquid distributor in the center of the rotor, and then sprayed out from the small hole of the distributor in the radial direction and enters the high-speed rotating packing. The liquid is cut by the packing and becomes a very small liquid film. , Liquid droplets, the gas is transported from the inlet pipe to the main chamber of the rotating bed, and under the push of pressure, it enters the rotating packing along the outer edge of the rotor, and contacts with the liquid countercurrently to complete the absorption or reaction process. Finally, the liquid thrown out from the rotor is intercepted by the shell of the main chamber and flows down along the shell wall, and is discharged from the drain pipe placed below, while the gas enters the gas collection chamber from the center of the rotor through the opening in the middle of the labyrinth seal. Then it is discharged from the exhaust pipe at the top of the bed. The gas and liquid are continuously sheared by the counter-rotating multi-layer packing in the rotor, and the directions are changed and redistributed many times. Compared with the ordinary rotating packed bed, the relative tangential slip velocity between the gas phase and the packing can be increased by an order of magnitude; The physical resistance can further promote the turbulent flow of the gas phase, and the filler transfers more kinetic energy to the fluid, which increases the turbulent kinetic energy and speeds up the update rate of the phase interface; the flow trajectory of the gas-liquid is more tortuous, and the residence time is also extended appropriately, so the gas-liquid gap The mass transfer rate has been greatly improved, which is also the main mechanism for the enhanced mass transfer of the rotating packed bed by reverse shearing of airflow.

Claims (9)

1. the rotary packed bed mass transfer of the reverse shearing of air-flow and consersion unit, comprise revolving bed main body (3), equipment supporter (7) and transmission device, it is characterized in that revolving bed main body (3) comprises upper and lower two parts: collection chamber (20) and main chamber (11), main chamber (11) and collection chamber (20) are isolated by dividing plate (25), being provided with in main chamber (11) can the filler rotor of High Rotation Speed, main chamber (11) top connects air inlet pipe (1), main chamber (11) bottom connected drainage pipe (4), filler rotor center arranges liquid distribution trough (13), liquid distribution trough (13) connects feed tube, collection chamber (20) top connects blast pipe (2), the perforate of filler rotor top is communicated with collection chamber (20), described filler rotor comprises the top rotary table (18) and lower rotary table (17) that independently rotate, top rotary table (18) bottom and lower rotary table (17) top are separately installed with some concentric annular packing supports, described packing support is tubular stainless steel coil, the densely covered perforate of circumference, the outer rim of packing support is provided with some form drag parts, described form drag part is Metal Flake projection, and profile is rectangle or triangle, is installed vertically on the outer rim of packing support.

2. the rotary packed bed mass transfer of the reverse shearing of air-flow according to claim 1 and consersion unit, it is characterized in that packing support inside is equipped with filler and is formed packing ring (12), packing ring on upper and lower rotating disk is nested against one another, gap is left between adjacent packing ring, top rotary table (18) top is connected with solid shafting (22), lower rotary table (17) bottom is connected with hollow shaft (14), and hollow shaft (14) top connects liquid distribution trough (13), and hollow shaft (14) bottom connects feed tube.

3. the rotary packed bed mass transfer of the reverse shearing of air-flow according to claim 2 and consersion unit, it is characterized in that described top rotary table (18) bottom and lower rotary table (17) top are respectively arranged with the groove of some concentric annular, packing ring (12) is fixed in groove, leaves gap in the groove that the free end of packing ring stretches into another rotating disk with the bottom land of another rotating disk.

4. the rotary packed bed mass transfer of the reverse shearing of the air-flow according to Claims 2 or 3 and consersion unit, is characterized in that dividing plate (25) center perforate and arrange tubular construction, solid shafting (22) is connected with top rotary table (18) through this hole.

5. the rotary packed bed mass transfer of the reverse shearing of air-flow according to claim 4 and consersion unit, it is characterized in that the position that described filler rotor top perforate is communicated with collection chamber arranges hermetically-sealed construction, described hermetically-sealed construction comprises top cover labyrinth (19) setting up and down and lower sealing cover (24), top cover labyrinth (19) is placed on tubular construction, lower sealing cover (24) is connected with top rotary table (18), lower sealing cover (24) center is uniform arranges some scallop holes, top cover labyrinth and lower sealing cover are provided with labyrinth ring, top cover labyrinth is embedded in together mutually with the labyrinth ring of lower sealing cover, the outmost turns of labyrinth ring arranges oil sealing felt collar.

6. the rotary packed bed mass transfer of the reverse shearing of air-flow according to claim 5 and consersion unit, is characterized in that air inlet pipe (1) connects main chamber (11) through collection chamber (20).

7. the rotary packed bed mass transfer of the reverse shearing of air-flow according to claim 6 and consersion unit, is characterized in that described hollow shaft (14) is connected with using swivel joint (5) between feed tube.

8. the rotary packed bed mass transfer of the reverse shearing of a kind of air-flow according to claim 7 and consersion unit, it is characterized in that described transmission device comprises hollow shaft (14), solid shafting (22), belt pulley (10), belt (6) and motor (9) composition, negative pulley wheel is all equipped with in hollow shaft (14) and solid shafting (22) outer end, is connected with motor (9) by belt (6).

9. the rotary packed bed mass transfer of the reverse shearing of a kind of air-flow according to claim 8 and consersion unit, it is characterized in that whole revolving bed main body (3) and motor (9) are installed on equipment supporter (7), revolving bed main body (3) is fixed on support (7) center by deck, motor (9) is fixed in the T-slot (8) at the upper and lower position of support (7), and motor set bolt can slide in T-slot (8).