Atomization rectification device

Abstract

The utility model discloses an atomization rectification device which comprises a rectification tower, a reboiler and a condenser. The rectifying tower is divided into a rectifying chamber, a distillation chamber and a stripping chamber which are relatively independent, heating cavities with a temperature adjusting function are wrapped outside the three chambers, and atomizers are arranged in the three chambers. A liquid return atomizer in the rectification chamber is communicated with a volatile steam pipe and a liquid return pipe, the volatile steam pipe provided with a volatile steam pump is communicated with the distillation chamber, and the rectification chamber is communicated with the condenser through a gas phase pipe provided with a gas phase pump. A raw material liquid atomizer in the distillation chamber is communicated with a feeding pipe and a mixed steam pipe, the mixed steam pipe provided with a mixed steam pump is communicated with the stripping chamber, and a floating ball valve is arranged at the bottom end of a residual liquid pipe to isolate the distillation chamber from the rectification chamber. A volatile liquid atomizer in the stripping chamber is communicated with a steam pipe and a volatile liquid pipe, the steam pipe provided with a steam pump is communicated with the reboiler, and the volatile liquid pipe is communicated with the distillation chamber. According to the utility model, atomized liquid is adopted to promote the dynamic process of rectification, and high-purity rectification is realized by adjusting temperature and chamber pressure, increasing relative volatility and strengthening rectification thermodynamics.

Description

Technical Field

[0001] The utility model is applied to the field of chemical industry and relates to the distillation separation of chemical products, in particular to a distillation device which adopts atomization mode for distillation. Background Art

[0002] Distillation is usually carried out in a distillation tower. The gas and liquid phases contact each other through countercurrent in the distillation tower. The liquid flows down along the tower plate, and the vapor flows up from the tower plate holes to carry out heat and mass transfer between the gas and liquid phases. The volatile components in the liquid phase enter the gas phase, and the non-volatile components in the gas phase are transferred to the liquid phase. Therefore, almost pure volatile components can be obtained at the top of the tower, and almost pure non-volatile components can be obtained at the bottom of the tower. The feed liquid is added from the middle of the tower. The tower section above the feed port further concentrates the volatile components in the rising steam, which is called the distillation section. The tower section below the feed port extracts the volatile components from the descending liquid, which is called the stripping section. The steam drawn from the top of the tower is condensed, and a part of the condensate is returned to the distillation tower from the top of the tower as reflux liquid, and the remaining distillate is the top product. The liquid drawn from the bottom of the tower is partially vaporized by the reboiler, and the steam rises along the tower, and the remaining liquid is the bottom product. The ratio of the amount of liquid refluxed into the tower from the top to the amount of product from the top is called the reflux ratio, and its size will affect the separation effect and energy consumption of the distillation operation.

[0003] Distillation towers can be roughly divided into plate towers and packed towers. The plates of plate towers can be divided into sieve plates, bubble caps, float valves, floating tongues, etc. The packing of packed towers can be divided into bulk packing, grid packing, corrugated packing, pulse packing, etc. In both tower types, liquid flows downward and gas flows upward, and the gas-liquid two-phase countercurrent contact exchanges heat and mass. The theoretical basis of distillation is the gas-liquid two-phase equilibrium, and the attached Figure 1 It is a txy diagram of multiple partial vaporizations, that is, a temperature-liquid-gas equilibrium phase diagram. At a certain temperature, the gas-liquid two-phase equilibrium satisfies the lever law. This diagram can help understand the working principle of the distillation tower. The left side is the liquid phase product at the bottom of the tower, and the right side is the gas phase product at the top of the tower. The feed is in the middle of the distillation tower, and the temperature gradually increases toward the bottom of the tower (left side) and gradually decreases toward the top of the tower (right side). Different temperature horizontal lines are equivalent to multiple tower plates. It can be seen from the attached figure that at x 2 and 2 There exists 1 and x 3 If the condensation and vaporization temperatures are appropriately chosen, y 1 and x 3 Close, so that if the intermediate product y 1 and x 3 The result of mixing and mass transfer not only eliminates the intermediate products, but also increases the yield of the final product. 1 and liquid x 3 When mixed directly, due to the liquid phase x 3 The temperature is lower than the gas phase 1temperature, therefore, the latent heat of high-temperature steam will heat the low-temperature liquid phase, and the heat transfer structure makes the liquid partially vaporized, while the steam itself is partially condensed. It can be seen that the liquid flowing up and down the tower plate and the rising gas make the upper-level liquid phase reflux directly contact with the lower-level gas phase, and the gas-liquid two phases with different temperatures and imbalance will inevitably produce the dual effects of heat transfer and mass transfer at the same time.

[0004] Attached Figure 1 The thermodynamic basis of distillation is explained, but it cannot be used directly to guide practice because the gas-liquid equilibrium constant is a function of temperature and pressure. Figure 1 Only temperature is considered, not pressure. The gas-liquid equilibrium constant is the ratio of the mole fraction of the component in the gas phase to the mole fraction of the component in the liquid phase, which is also equal to the ratio of the saturated vapor pressure of the component at the boiling point to the partial pressure of the component in the gas phase. It is a single-component gas-liquid equilibrium concept. The saturated vapor pressure is related to temperature. Different substances have different functional relationships between saturated vapor pressure and temperature. In most cases, the Antoine formula is applied. The partial pressure of the component is the product of the total pressure and the mole fraction of the component in the gas phase, and is related to the total pressure. Only when the temperature and total pressure are determined, the gas-liquid equilibrium constant is a constant, which determines the number of moles of the component in the gas and liquid phases.

[0005] Taking the presence of two components A and B in the mixed liquid as an example, the thermodynamic equation of distillation is as follows:

[0006] Bubble point equation:

[0007] Dew point equation:

[0008] Gas-liquid equilibrium equation:

[0009] In the above formula: is the saturated vapor pressure of the volatile component A;

[0010] is the saturated vapor pressure of the non-volatile component B;

[0011] P is the total gas pressure;

[0012] α is the relative volatility, which is the ratio of the saturated vapor pressures of the components, that is,

[0013] x A is the molar fraction of component A in the liquid phase;

[0014] y A is the molar fraction of component A in the gas phase;

[0015] From the gas-liquid equilibrium equation, it can be seen that when the temperature is constant, the saturated vapor pressure of components A and B is constant, and the relative volatility α is constant. When the temperature changes, if the relative volatility α increases, then y A Increase. From the bubble point equation and the dew point equation, it can be seen that when the total pressure increases, x A Increase, y A Therefore, the thermodynamic control of distillation, for the top product, controls the temperature, increases the relative volatility α, and increases the total pressure P to increase y A , purify the gas phase product. For the bottom product, similarly, increase the relative volatility α, reduce the total pressure P, and reduce x A , increase x B , purify the liquid product.

[0016] In actual production and operation of the plate-type distillation tower, three balances should be mastered, namely material balance, gas-liquid phase balance and heat balance. Material balance means that the amount of material entering the tower per unit time should be equal to the sum of the amounts of materials leaving the tower, which is mainly adjusted by the feed amount and the discharge amount at the top and bottom of the tower. During operation, when the total material balance is not met, it can be reflected in the change of the tower pressure difference. If more is fed in and less is discharged, the tower pressure difference will rise. The tower pressure difference of the distillation tower should be within a certain range. If the tower pressure difference is too large, the rising speed of the steam in the tower is too large, the mist entrainment is serious, and even liquid flooding occurs; if the tower pressure difference is too small, the rising speed of the steam is too small, the gas-liquid two-phase mass transfer effect on the tower plate is reduced, and even leakage occurs. Material balance is a key in tower operation. If the normal material balance is destroyed, it will affect the other two balances, that is, the gas-liquid phase balance cannot achieve the expected effect, and the heat balance is destroyed and needs to be readjusted. The gas-liquid phase balance mainly reflects the quality and loss of the product, which is achieved by adjusting the tower temperature, pressure and gas-liquid contact on the tower plate. Only when the temperature and pressure are stable and the volatility coefficient is relatively stable, can there be a gas-liquid phase equilibrium composition. When the temperature and pressure change, the volatility coefficient is unstable, and the quality and loss of the product change accordingly. Gas-liquid phase equilibrium is closely related to material balance. Only when the material balance is stable, the temperature and pressure are stable, and the volatility coefficient is stable, can gas-liquid phase equilibrium be achieved. Heat balance refers to the balance of heat entering the tower and heat leaving the tower. It is the basis for the realization of material balance and gas-liquid phase equilibrium, and in turn depends on the two balances. Without hot gas phase and cold liquid reflux, the entire distillation process cannot be achieved. If the composition of the gas-liquid phase equilibrium in the tower changes, the heat release of gas phase condensation and the heat absorption of liquid vaporization will also change accordingly. Therefore, material balance, gas-liquid phase balance and heat balance are the key to the operation of distillation, and the three balances influence and restrict each other. In operation, it is usually based on controlling material balance, adjusting heat balance accordingly, and the ultimate goal is to achieve gas-liquid phase equilibrium. In other words, the plate distillation tower cannot freely control the gas-liquid phase equilibrium, and can only be adjusted through material balance and heat balance.

[0017] In order to reduce the height of the distillation tower and increase the vapor-liquid interface area, CN107297084A discloses an atomizing tower plate and an atomizing tower plate distillation tower, wherein a liquid phase atomizing device is installed on the tower plate, including a truncated cone-shaped inlet section, a cylindrical throat and a trumpet-shaped outlet section, and liquid phase injection holes are evenly distributed on the throat. When the liquid phase passes through the injection hole, it is cut into fine droplets by the gas phase, and the droplet diameter is micrometer-level, which greatly increases the contact area of ​​the gas-liquid two-phase and greatly improves the transmission efficiency of the gas-liquid two-phase. Due to the slow flow rate of the liquid phase and the gas phase, the effect of the gas phase cutting the liquid phase is limited, and the droplets are difficult to be atomized into micrometer level. CN105920861A discloses a spray distillation device, wherein a raw material liquid atomizer connected to a raw material liquid feed pipe is installed on the upper part of the evaporation chamber shell, and a water vapor distributor connected to a water vapor inlet pipe is installed on the lower part, and a plurality of water vapor nozzles are evenly distributed on the water vapor distribution plate. The upper end of the shell is connected to the distillation column, which is filled with packing or orifice plates. The upper part of the distillation column has a reflux water sprinkling ring, and the lower part has a reflux air cap and a residual liquid outflow port. The lower end of the shell is connected to the residual liquid processor, and the residual liquid processor is alternately installed with large and small residual liquid processing disks. The residual liquid processing disk is installed with a residual liquid heating ring that is heated by steam, and the bottom of the residual liquid processor has a waste liquid discharge port. The reflux liquid treatment device is installed circumferentially on the inner wall of the evaporation chamber shell. The upper part of the device has a reflux liquid conduit and a water sprinkling ring. The reflux liquid conduit is connected to the residual liquid outflow port of the distillation column. The middle part is a packing mesh ring, and the lower part has a mounting plate. The mounting plate is evenly distributed with residual liquid air caps, and the lower part is designed with a residual liquid discharge pipe, which guides the residual liquid to the residual liquid treatment plate. Compared with the traditional distillation tower, the similarity of this patent application is that the volatile phase distillation still uses the traditional packing method. The volatile phase vapor passes through the residual liquid air cap and enters the packing column, and is concentrated by mass transfer and heat transfer with the reflux liquid coming down from the packing or orifice plate. The residual liquid formed in the distillation column is sprinkled on the packing mesh ring through the residual liquid outflow outlet, the reflux liquid conduit and the watering ring, and transfers heat and mass with the steam coming up from below, and the volatile phase evaporates upward, while the non-volatile phase descends. There are three main differences: 1) The raw liquid is atomized separately, and it is heated and vaporized by the steam; 2) The entire distillation process of the reflux liquid becoming the residual liquid does not pass through the evaporation chamber; 3) A residual liquid processor is added at the bottom, and the residual liquid is heated by the heating ring, and the volatile phase continues to evaporate. Although the patent application atomizes the raw liquid and improves the distillation efficiency, the reflux liquid is not atomized, but the traditional packing distillation method is used, which does not improve the distillation efficiency. The applicant previously applied for a utility model patent "A kind of atomized distillation tower", which is basically consistent with the above two patent applications. Both solve the dynamic problems of distillation and improve the distillation efficiency by increasing the gas-liquid phase interface. On the basis of the above patent application, this application solves the dynamic problems of distillation to reduce the height of the distillation tower and improve the purity of the bottom and top products. Utility Model Content

[0018] The technical problem solved by the utility model is to provide an atomization distillation device, which makes each chamber of the distillation tower independent on the basis of liquid atomization enhanced dynamics, so as to facilitate the control of its temperature and pressure, so as to achieve thermodynamic control of each stage of distillation and realize high purity of the tower top product.

[0019] The technical solution adopted by the utility model is: the atomization distillation device includes a distillation tower, a reboiler, and a condenser. The distillation tower is separated into independent distillation chambers, distillation chambers, and stripping chambers. The three chambers are not directly connected, but are connected through a closed pipeline. The outside of the distillation chamber wraps the heating chamber I, and a liquid return atomizer is arranged inside. The liquid return atomizer is connected to the volatile steam pipe and the liquid return pipe, the volatile steam pipe is connected to the distillation chamber, and the liquid return pipe is connected to the condenser; the condenser is connected to the top of the distillation chamber through a gas phase pipe, and a gas phase pump is arranged on the gas phase pipe; the volatile steam pipe and the liquid return pipe are respectively provided with a volatile steam pump and a liquid return pump. The outside of the distillation chamber wraps the heating chamber II, and a raw liquid atomizer and a residual liquid pipe are arranged inside. The raw liquid atomizer is connected to the feed pipe and the mixed steam pipe, the mixed steam pipe is connected to the stripping chamber, and a mixed steam pump is arranged on the mixed steam pipe. A float valve is arranged at the bottom of the residual liquid pipe, and the float valve can be opened or closed according to the chamber pressure connecting the two chambers. The stripping chamber is wrapped with a heating chamber III on the outside, and a volatile liquid atomizer is arranged inside. The volatile liquid atomizer is connected to the steam pipe and the volatile liquid pipe. The volatile liquid pipe is connected to the bottom of the distillation chamber; the steam pipe is connected to the top of the reboiler, and a steam pump and a regulating valve are arranged on the steam pipe. The reboiler is connected to the bottom of the stripping chamber through a liquid phase pipe. The heating chamber is used to assist the temperature control of the three chambers, and the booster pump is used for gas pressurization of liquid atomization. The chamber pressure of each chamber is controlled by the chamber volume and the flow rate of the booster pump.

[0020] Furthermore, the liquid return atomizer, the raw material liquid atomizer and the volatile liquid atomizer have the same structure, including a steam ring pipe, a liquid ring pipe and a nozzle. The steam ring pipe is connected to the volatile steam pipe, or the mixed steam pipe, or the steam pipe, and the corresponding liquid ring pipe is connected to the liquid return pipe, or the feed pipe, or the volatile liquid pipe.

[0021] Furthermore, the nozzles are evenly distributed on the steam ring pipe and the liquid ring pipe, and the nozzle includes a steam riser, a liquid riser, a threaded ring, a steam spray disc and a fixed rod. The steam riser is connected to the steam ring pipe, the liquid riser is connected to the liquid ring pipe, and the steam riser is sleeved in the liquid riser. A steam spray disc is arranged at the port of the steam riser, and the steam spray disc is fixedly connected to the threaded ring through a fixed rod, and the threaded ring is threadedly connected to the end of the liquid riser. The steam spray disc is a spherical or ellipsoidal surface, which cooperates with the arc surface of the inner edge of the port of the steam riser to form a slit-shaped steam spray port, which cooperates with the liquid spray port at the end of the liquid riser, and the high-speed gas rushing out of the steam spray port can cut the liquid at the liquid spray port into micron-sized fine droplets.

[0022] Furthermore, for the raw material liquid with a relatively low volatility, a pre-rectification chamber is set between the rectification chamber and the distillation chamber, and a pre-rectification atomizer is set in the pre-rectification chamber. The structure of the pre-rectification atomizer is consistent with the above three atomizers, the liquid ring pipe is connected to the bottom of the rectification chamber, and the steam ring pipe is connected to the distillation chamber. The residual liquid pipe connects the distillation chamber and the pre-rectification chamber. A pre-stripping chamber can also be set between the distillation chamber and the stripping chamber, and a pre-stripping atomizer is set in the pre-stripping chamber. The structure of the pre-stripping atomizer is consistent with the above three atomizers, the liquid ring pipe is connected to the bottom of the distillation chamber, the steam ring pipe is connected to the stripping chamber, and the residual liquid pipe connects the pre-stripping chamber and the pre-rectification chamber. In this way, the residual liquid after rectification is transported from the pre-rectification chamber to the volatile liquid atomizer in the stripping chamber for atomization and stripping.

[0023] Furthermore, in order to prevent the fine liquid droplets from being extracted together with the gas by the mixed steam pump, the volatile steam pump and the gas phase pump, which would affect the rectification gas-liquid balance and the purity of the tower top product, the rectification chamber, the distillation chamber and the stripping chamber are all provided with gas-liquid separators, which are arranged above the atomizer of each chamber and below the gas extraction port.

[0024] Furthermore, in order to reduce the height of the equipment and facilitate the independent volume and size design of the three chambers, the rectification chamber, the distillation chamber and the stripping chamber are separately arranged.

[0025] Furthermore, the float valve comprises an outer tube, a stop rod and a float. The outer tube is fixed at the bottom end of the residual liquid pipe, the float is placed inside the outer tube and above the stop rod, and the stop rod is fixed at the lower end of the outer tube.

[0026] The beneficial effects of the utility model are as follows: the utility model adopts an atomizer to atomize the liquid into micron-sized fine droplets, increases the gas-liquid interface area, and promotes the dynamic process of distillation. On this basis, for the raw material liquid, by adjusting the temperature and chamber pressure, the relative volatility is increased, and the distillation thermodynamics is strengthened, so as to achieve rapid distillation of volatile components and improve the purity of the distillation product of volatile components. The utility model separates distillation, stripping and rectification, and controls them separately, which greatly reduces the height of the distillation tower, simplifies the equipment structure, and saves the equipment manufacturing and installation costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is the temperature-liquid-gas equilibrium phase diagram for multiple partial vaporizations;

[0028] Figure 2 is a schematic diagram of the front view of the structure of Example 1;

[0029] Figure 3 It is a schematic diagram of the structure of the atomizer and the nozzle;

[0030] Figure 4 yes Figure 3 BB cross-sectional view;

[0031] Figure 5 It is a schematic diagram of the structure of the float valve;

[0032] Figure 6 is a schematic diagram of the structure of Example 2;

[0033] Figure 7 is a schematic diagram of the structure of Example 3;

[0034] Figure 8 is a schematic diagram of a structural front view of Example 4;

[0035] Fig. 9 is another structural front view schematic diagram of embodiment 4;

[0036] Fig.10 is a schematic diagram of the front view of the structure of Example 5;

[0037] In the figure: 1-rectification chamber, 2-distillation chamber, 3-stripping chamber, 4-reboiler, 5-lower baffle, 6-upper baffle, 7-nozzle, 8-condenser, 9-gas-liquid separator;

[0038] 11-volatile steam pump, 12-volatile steam pipe, 13-heating chamber I, 14-liquid return atomizer, 15-gas phase pipe, 16-gas phase pump, 17-liquid return pump, 18-liquid return pipe, 19-pre-distillation chamber;

[0039] 21-residual liquid pipe, 22-feeding pipe, 23-raw liquid atomizer, 24-float valve, 25-heating chamber II, 26-mixing steam pump, 27-mixing steam pipe;

[0040] 31-volatile liquid pipe, 32-volatile liquid atomizer, 33-heating chamber III, 34-liquid phase pipe, 35-steam pump, 36-steam pipe, 37-pre-stripping distillation chamber;

[0041] 41-steam ring pipe, 42-liquid ring pipe;

[0042] 71-steam riser, 72-liquid riser, 73-threaded ring, 74-steam spray plate, 75-steam spray port, 76-liquid spray port, 77-fixing rod;

[0043] 241-outer tube, 242-stop rod, 243-floating ball. DETAILED DESCRIPTION

[0044] The following "up and down" refers to the relative position of the upper and lower parts in the state of use, that is, Figure 2 The solid arrows in the attached drawings indicate the flow direction of the liquid, and the dotted arrows indicate the flow direction of the gas. The following "Ⅰ, Ⅱ, Ⅲ" do not indicate the order, but are only for the purpose of distinguishing the components and describing the structure.

[0045] For ease of understanding, the "gas" and "liquid" mentioned below are relative, such as gas-liquid, gas phase-liquid phase. The "volatile vapor" mentioned below refers to the gas mainly composed of volatile components, and the "steam" mainly refers to the gas mainly composed of non-volatile components.

[0046] Since the degree of freedom of the gas-liquid binary equilibrium system is 2, the gas-liquid phase equilibrium constant is determined by pressure and temperature. For multicomponent mixtures, the degree of freedom is equal to the number of components. The composition of the gas-liquid phase is not completely determined by temperature and pressure, but for the same component, the equilibrium constants in different multicomponent mixtures are often close or the same, so the following discussion of the gas-liquid phase equilibrium constant takes temperature and pressure as the influencing factors.

[0047] Example 1.

[0048] The atomization distillation device of this embodiment is shown in the attached Figure 2 , including a distillation tower, a reboiler 4, a condenser 8, etc. The distillation tower is divided into an upper distillation chamber 1, a middle distillation chamber 2, and a lower stripping chamber 3 by an upper partition 6 and a lower partition 5. The three chambers are not directly connected, but connected through a closed pipeline.

[0049] The outside of the distillation chamber 1 is wrapped with a heating chamber Ⅰ13, and a liquid return atomizer 14 is arranged inside. The heating chamber Ⅰ13 is used for temperature control of the distillation chamber 1. A high-energy gas for heating, such as water vapor or high-temperature air, is introduced into the heating chamber Ⅰ13 to assist in heating the distillation chamber 1, so as to increase the temperature of the distillation chamber 1. The heating chamber Ⅰ13 can also be heated by electricity or other heating methods. If it is necessary to lower the temperature of the distillation chamber 1, a refrigerant, such as cooling water or low-temperature gas, can be introduced into the heating chamber Ⅰ13. The structure of the liquid return atomizer 14 is shown in the attached Figure 3 , including a steam ring pipe 41, a liquid ring pipe 42 and a nozzle 7. The steam ring pipe 41 of the atomizer is connected to the volatile steam pipe 12, and the volatile steam pipe 12 is connected to the distillation chamber 2. The liquid ring pipe 42 is connected to the liquid return pipe 18, and the liquid return pipe 18 is connected to the bottom of the condenser 8. The condenser 8 is connected to the top of the distillation chamber 1 through the gas phase pipe 15, and a gas phase pump 16 is arranged on the gas phase pipe 15. The volatile steam pump 11 and the liquid return pump 17, as well as a regulating valve (not shown in the drawings) are respectively arranged on the volatile steam pipe 12 and the liquid return pipe 18. The flow rate of the liquid return pump 17 meets the design flow rate requirements of the reflux liquid, and the flow rate and pressure of the liquid return pump 17 can be adjusted by the regulating valve. The flow rate of the volatile steam pump 11 meets the volatile steam flow rate requirements entering the distillation chamber 1, and the flow rate and pressure of the volatile steam pump 11 can be adjusted by the regulating valve. The gas phase pump 16 is linked with the volatile steam pump 11 to ensure the balance of the air intake and the air output.

[0050] The nozzles 7 are evenly distributed on the steam ring pipe 41 and the liquid ring pipe 42. Figure 3 and attached Figure 4As shown, it includes a steam riser 71, a liquid riser 72, a threaded ring 73, a steam spray disc 74 and a fixed rod 77. The steam riser 71 is connected to the steam ring pipe 41, and the liquid riser 72 is connected to the liquid ring pipe 42. The steam riser 71 is sleeved in the liquid riser 72, and the port of the liquid riser 72 is a liquid spray port 76. The steam spray disc 74 is arranged at the port of the steam riser 71. The shape of the steam spray disc 74 is a sphere or an ellipsoid, which cooperates with the arc surface of the inner edge of the port of the steam riser 71 to form a slit-shaped steam spray port 75. The gas can be quickly sprayed out through the slit-shaped steam spray port 75 along the two arc surfaces, and the liquid flowing out of the liquid spray port 76 can be cut into micron-level fine droplets. The steam spray disc 74 is fixedly connected to the threaded ring 73 through the fixed rod 77, and the threaded ring 73 is threadedly connected to the end of the liquid riser 72. This structure has two advantages. First, the two arc surfaces are processed separately, that is, the arc surface of the steam spray plate 74 and the inner arc surface of the steam riser 71 port are convenient to process, which is convenient for making the Laval-like slit-shaped steam spray port 75. Second, the steam spray plate 74 is threaded, which is conducive to adjusting the size of the slit of the steam spray port 75, thereby adjusting the size of the atomized droplets to achieve the desired atomization effect.

[0051] The top of the distillation chamber 2 is an upper partition 6, and the bottom is a lower partition 5. The outer side wraps the heating chamber II 25, and the raw material liquid atomizer 23 and the residual liquid pipe 21 are arranged inside. The heating chamber II 25 has the same function as the heating chamber I 13, which is auxiliary heating or cooling and is used to adjust the temperature of the distillation chamber 2. The upper partition 6 is an inclined plate or an arc plate, which is used to collect and guide the residual liquid in the distillation chamber 1. The residual liquid port is processed at the lowest point of the upper partition 6. The residual liquid port is connected to the residual liquid pipe 21. The bottom end of the residual liquid pipe 21 is provided with a float valve 24. The structure of the float valve 24 is shown in the attached figure. Figure 5 As shown, it includes an outer tube 241, a baffle 242, and a float 243. The outer tube 241 is fixed at the bottom end of the residual liquid tube 21, and the float 243 is placed inside the outer tube 241 and above the baffle 242. The baffle 242 is fixed at the lower end of the outer tube 241. When the pressure difference between the distillation chamber 2 and the rectification chamber 1 is less than the residual liquid pressure in the residual liquid tube 21, the residual liquid flows downward, the float 243 falls, and the baffle 242 supports the float 243. When the pressure difference between the distillation chamber 2 and the rectification chamber 1 is greater than the residual liquid pressure in the residual liquid tube 21, the float 243 moves upward to block the residual liquid tube 21 to prevent the pressure in the distillation chamber 2 from affecting the pressure in the rectification chamber 1. The structure of the raw liquid atomizer 23 is consistent with that of the liquid return atomizer 14, including a steam ring tube 41, a liquid ring tube 42 and a nozzle 7, see attached Figure 3 and attached Figure 4 As shown. The liquid ring pipe 42 of the raw material liquid atomizer 23 is connected to the feed pipe 22, and the feed pipe 22 is used to feed the raw material liquid into the distillation chamber 2. The steam ring pipe 41 of the raw material liquid atomizer 23 is connected to the mixed steam pipe 27, and the mixed steam pipe 27 is connected to the distillation chamber 3. A mixed steam pump 26 is arranged on the mixed steam pipe 27. The mixed steam pump 26 has the same purpose as the volatile steam pump 11, pressurizing the gas and feeding it into the nozzle 7 to atomize the raw material liquid fed into the atomizer, and atomize the raw material liquid into micron-sized fine droplets to increase the gas-liquid interface area.

[0052] The top of the stripping chamber 3 is a lower partition 5, and the bottom is connected to the reboiler 4 through a liquid phase pipe 34. The outer side wraps a heating chamber III 33, and a volatile liquid atomizer 32 is arranged inside. The heating chamber III 33 has the same function as the above two heating chambers, and is used to assist heating or cooling and to adjust the temperature of the stripping chamber 3. The structure of the volatile liquid atomizer 32 is consistent with that of the liquid return atomizer 14, and both include a steam ring pipe 41, a liquid ring pipe 42 and a nozzle 7. Here, the steam ring pipe 41 is connected to the steam pipe 36, and the liquid ring pipe 42 is connected to the volatile liquid pipe 31, and the volatile liquid pipe 31 is connected to the residual liquid port of the lower partition 5. The lower partition 5 is arc-shaped or spherical, and the residual liquid port is located at the lowest point in the middle of the lower partition 5, which is used to collect and guide the volatile liquid in the distillation chamber 2 into the volatile liquid atomizer 32. The steam pipe 36 is connected to the top of the reboiler 4, and a steam pump 35 and a regulating valve are arranged on the steam pipe 36. The steam pump 35 can adjust the flow rate and pressure through the regulating valve.

[0053] The distillation process of this embodiment is as follows: 1) distillation of raw liquid. The raw liquid is fed into the raw liquid atomizer 23 in the distillation chamber 2 through the feed pipe 22. At the liquid spray port 76, the raw liquid is atomized into micron-sized droplets under the cutting action of the mixed steam sprayed at high speed from the steam spray port 75. Part of the raw liquid evaporates and becomes volatile gas together with the mixed steam. When the gas-liquid equilibrium is reached, the raw liquid can be adjusted according to x. A (the molar fraction of the volatile component A in the raw material liquid) and α (relative volatility), y is calculated from the gas-liquid equilibrium equation A (The molar fraction of volatile component A in the volatile vapor). The liquid droplets greatly increase the interfacial area of ​​the gas-liquid two phases, improve the vaporization heat and mass transfer kinetics, and reduce the time to reach gas-liquid equilibrium, thereby improving the distillation speed and efficiency. The volatile vapor enters the liquid return atomizer 14 in the distillation chamber 1 through the volatile vapor pipe 12. The liquid after volatilization of the raw liquid and the residual liquid flowing into the residual liquid pipe 21 become volatile liquid together, and enter the volatile liquid atomizer 32 in the distillation chamber 3 from the volatile liquid pipe 31. 2) The volatile vapor is sent into the liquid return atomizer 14 in the distillation chamber 1 by the volatile vapor pump 11, and is sprayed out at high speed from the steam injection port 75. The reflux liquid sent into the atomizer liquid riser 72 by the liquid return pump 17 is cut and atomized into micron-sized fine droplets, and the volatile component is distilled in the distillation chamber 1. When the gas-liquid equilibrium is reached, it can be obtained by x A and α, the gas-liquid equilibrium equation calculates y A . Usually, x A is approximately 1, so y A=1, thereby achieving the distillation of the volatile component A. The distilled gas is sent to the condenser 8 by the gas phase pump 16 through the gas phase pipe 15, condensed into liquid, and partially refluxed to the liquid return atomizer 14 to become reflux liquid. The non-volatile components in the volatile gas condense into liquid to form residual liquid, which flows into the distillation chamber 2 through the residual liquid pipe 21. 3) The volatile liquid atomizer 32 in the stripping chamber 3, in addition to receiving the volatile liquid in the distillation chamber 2, also receives the steam sent from the reboiler 4 by the steam pump 35, which includes the non-volatile component steam and the heating water vapor. In the nozzle 7 of the volatile liquid atomizer 32, the high-speed steam sprayed cuts the volatile liquid into micron-sized fine droplets, and distills it in the stripping chamber 3, and almost all the volatile components in the residual liquid are evaporated. Calculated on the basis of a relative volatility of 15 and a molar fraction of component A in the raw liquid of 20%, after distillation and rectification, the molar fraction of component A in the gas phase can reach more than 99.9%.

[0054] The above distillation process focuses on describing the dynamics of distillation, rectification and stripping, strengthening the atomized droplets and increasing the gas-liquid interface. The control of distillation dynamics is as follows: 1) Determine the temperature. Increase the relative volatility under relatively low cost conditions. Relative volatility is determined by saturated vapor pressure, and the main factor affecting saturated vapor pressure is temperature. Consider the temperature control cost and relative volatility comprehensively to determine the appropriate temperature. The temperature control of the distillation chamber 1, distillation chamber 2 and stripping chamber 3 can be controlled by steam and heating chambers, and the temperature of the three chambers can be controlled within a consistent range to ensure that the volatile components remain within a higher relative volatility range. 2) Determine the chamber pressure. Chamber pressure refers to the gas pressure in the distillation chamber 1, distillation chamber 2 and stripping chamber 3, which is not the same concept as the gas pressure of the booster pump. The pressure provided by booster pumps such as steam pump 35, mixed steam pump 26 and volatile steam pump 11 is used to atomize liquid, which is not equal to the chamber pressure. When the temperature is constant, the chamber pressure depends on the amount of gas in each chamber and the volume of each chamber. Under the premise of material balance, the chamber pressure mainly depends on the volume of each chamber. Under the condition that the volume of each chamber is constant, the control of the chamber pressure mainly depends on the flow of the steam pump 35, the mixed steam pump 26, the volatile steam pump 11 and the gas phase pump 16, that is, it depends on the regulating valve on each booster pump pipeline. The three chambers are separated by a float valve 24 and an atomizer, and the pressure control is relatively independent. Even if the chamber pressure of the stripping chamber 3 is higher than that of the distillation chamber 2, the steam pressure that plays an atomizing role at the nozzle of the volatile liquid atomizer 32 is greater than the chamber pressure of the stripping chamber 3. In addition, the steam ejected from the steam outlet 75, which is similar in structure to the Laval nozzle, generates negative pressure locally, and the volatile liquid is sucked into the volatile liquid atomizer 32. Therefore, the volatile liquid will not flow back into the distillation chamber 2 due to the high chamber pressure of the stripping chamber 3, thereby separating the stripping chamber 3 from the distillation chamber 2. Similarly, the distillation chamber 2 and the rectification chamber 1 are separated by a float valve 24 and a raw liquid atomizer 23. That is to say, when the volumes of the rectification chamber 1, the distillation chamber 2 and the stripping chamber 3 are constant and the raw material liquid is stable, the chamber pressures of the three chambers can be stably controlled.

[0055] The factors affecting the temperature control of the stripping chamber 3 include steam temperature, volatilization heat absorption of volatile components, and liquefaction heat release of non-volatile components. The temperature control of the stripping chamber 3 mainly depends on the steam temperature from the reboiler 4, and the heating chamber III 33 mainly plays a role in heat preservation. If the heating cost of the reboiler 4 is high, or the temperature control is delayed, or the material is unbalanced, or for other reasons, the heating chamber III 33 can also be used to assist in temperature control. When the material is balanced, the heat absorption and heat release in the stripping chamber are stable, and the steam temperature can be stably controlled. The factors affecting the chamber pressure control of the stripping chamber 3 include the steam inlet amount, the discharge amount of the mixed steam, the gas amount increased by the volatilization of the volatile components, and the gas amount reduced by the liquefaction of the non-volatile components. The gas flow rate of the steam pump 35 and the mixed steam pump 26 is the main factor in the chamber pressure control of the stripping chamber 3. If the gas flow rate of the steam pump 35 is large, and the gas flow rate of the mixed steam pump 26 is small, the chamber pressure of the stripping chamber 3 will increase, and on the contrary, the chamber pressure will decrease. Under the condition of material balance, the gas flow rates of the steam pump 35 and the mixed steam pump 26 are stable, and the pressure in the stripping chamber 3 is stable.

[0056] The factors affecting the temperature control of distillation chamber 2 include the mixed steam temperature, the volatilization heat absorption of the volatile component, and the liquefaction heat release of the non-volatile component, while the residual liquid has little effect on the temperature. When the unit volatilization heat absorption and unit liquefaction heat release of the raw material liquid component are constant, since the temperature of the retention chamber is stable and the temperature of the mixed steam is stable, the main factors affecting the temperature of the distillation chamber are the amount of raw material liquid entering and the component ratio. When the raw material liquid is unstable, the temperature control of the heating chamber II 25 is particularly important under the premise of stable control of the mixed steam temperature. When the raw material liquid is stable, the temperature of the heating chamber II 25 can also be stable, thereby ensuring the stability of the distillation chamber temperature. The factors affecting the chamber pressure control of distillation chamber 2 include the amount of mixed steam entering, the amount of volatile gas generated and discharged. When the raw material liquid is unstable, the chamber pressure of the distillation chamber is mainly controlled by the flow rate of the volatile steam pump 11 and the amount of raw material liquid entering. The chamber pressure of the distillation chamber can be increased by reducing the flow rate of the volatile steam pump 11 or increasing the volatile components in the raw material liquid, and vice versa.

[0057] The factors affecting the temperature control of the distillation chamber 1 include the volatile vapor temperature and component content, the liquid return temperature and the reflux ratio, that is, the volatile component absorbs heat during volatilization and the non-volatile component releases heat during liquefaction. Since the volatilization of the volatile component in the distillation chamber is the main process, in order to ensure the high purity of the volatile component in the distillation chamber and reasonably increase the relative volatility, the temperature control of the heating chamber Ⅰ13 is particularly important. Under the condition of material balance, the liquid return reflux ratio and the temperature of the heating chamber Ⅰ13 are focused on to ensure the temperature stability of the distillation chamber. The factors affecting the pressure control of the distillation chamber 1 include the volatile vapor inlet amount, the liquid return amount, the gas phase discharge amount of the gas phase pump 16, and the gas amount reduced by the liquefaction of the non-volatile component. Under the condition of stable reflux ratio and volatile vapor inlet amount, the distillation chamber pressure mainly depends on the gas phase discharge amount control of the gas phase pump 16. If the discharge amount decreases, the chamber pressure increases, and on the contrary, the chamber pressure decreases.

[0058] It should be noted that the above description is based on the temperature control above room temperature, mainly for heating. If the temperature needs to be controlled below room temperature, low-energy gas or liquid, such as cryogenic or liquid nitrogen, is introduced into the heating chamber to obtain the low temperature required by the process.

[0059] Example 2.

[0060] In Example 1, the fine droplets floating in the three chambers after atomization by the atomizer may be pumped out together with the gas by the mixed steam pump 26, the volatile steam pump 11 and the gas phase pump 16, affecting the rectification gas-liquid balance and the purity of the top product. Figure 6 As shown. The gas-liquid separator 9 is arranged above the atomizer and below the gas outlet. Its function is to separate the gas and liquid, the gas is extracted, and the liquid is filtered and isolated, retained in the room, and flows out from the bottom. The structure of the gas-liquid separator 9 is separately patented.

[0061] Example 3.

[0062] The structure of this embodiment is shown in the attached Figure 7 As shown, the atomizer nozzles 7 of the above two embodiments are oriented downward, while the nozzles 7 of this embodiment are oriented upward. When the nozzles 7 are oriented upward, the sprayed fine droplets have a falling process, which helps to increase the contact time between the gas and liquid interfaces, and can reduce the height of the three chambers, thereby reducing the height of the distillation tower.

[0063] Example 4.

[0064] For raw material liquid with relatively low volatility, a rectification chamber can be added above the distillation chamber 2 to purify the gas phase. Figure 8As shown, the distillation tower is divided into a relatively independent distillation chamber 1, a pre-distillation chamber 19, a distillation chamber 2 and a stripping chamber 3 from top to bottom by a plurality of partitions. A pre-distillation chamber 19 is added between the distillation chamber 2 and the distillation chamber 1. A pre-distillation atomizer is arranged in the pre-distillation chamber 19, and the structure of the atomizer is the same as the above-mentioned atomizer. The liquid ring pipe 42 is connected to the bottom of the upper distillation chamber 1, and the vapor ring pipe 41 is connected to the distillation chamber 2. A residual liquid pipe 21 is arranged at the bottom of the partition separated from the distillation chamber 2, and the residual liquid after distillation flows into the distillation chamber 2 and is transported to the volatile liquid atomizer 32 of the stripping chamber 3 for atomization and stripping.

[0065] A pre-stripping distillation chamber 37 may also be added to the lower portion of the distillation chamber 2, as shown in the attached Fig. 9 As shown, the liquid phase is purified. The distillation tower is divided into a relatively independent distillation chamber 1, a pre-distillation chamber 19, a distillation chamber 2, a pre-stripping distillation chamber 37 and a stripping chamber 3 from top to bottom by a plurality of partitions. A pre-stripping atomizer is arranged in the pre-stripping distillation chamber 37, and the structure of the atomizer is the same as the above-mentioned atomizer. The liquid ring pipe 42 is connected to the bottom of the distillation chamber 2, and the vapor ring pipe 41 is connected to the stripping chamber 3. The residual liquid pipe 21 is connected to the pre-stripping distillation chamber 37 and the pre-distillation chamber 19. The residual liquid after distillation flows from the pre-distillation chamber 19 into the pre-stripping distillation chamber 37 and is transported to the volatile liquid atomizer 32 of the stripping chamber 3 for atomization and stripping.

[0066] Example 5.

[0067] In this embodiment, the rectifying chamber 1, the distillation chamber 2 and the stripping chamber 3 are separately arranged. Fig.10 As shown, it is beneficial to reduce the height of the equipment and is also beneficial to the independent volume and size design of the three chambers.

[0068] There are various structures of atomizers and nozzles. The nozzle structure provided by the utility model can ensure uniform atomization of the liquid, has a simple structure, is easy to manufacture, and separates multiple chambers such as the rectification chamber, the distillation chamber and the stripping chamber to avoid the mutual influence of the chamber pressures of each chamber.

[0069] The utility model can also be applied to extractive distillation and azeotropic distillation, and the extractant or entrainer is fed into the raw material liquid atomizer together with the raw material liquid. Extractive distillation increases the relative volatility by changing the vapor pressure of the components, and azeotropic distillation increases the relative volatility by reducing the boiling point of the new azeotrope, which is basically consistent with the idea of ​​increasing the relative volatility by adjusting the temperature and pressure of the utility model.

[0070] The utility model adopts an atomizer to atomize the liquid into micron-sized fine droplets, increase the gas-liquid interface area, promote the dynamic process of distillation, and improve the distillation efficiency. The temperature and pressure of the bottom of the traditional integrated distillation tower are higher than the temperature and pressure of the upper part, and cannot be adjusted according to needs in the distillation tower. The utility model separates distillation, stripping and distillation, and controls them separately. On the basis of increasing dynamics, the temperature and chamber pressure are selectively adjusted for the raw material liquid to increase the relative volatility and strengthen the distillation thermodynamics, thereby achieving rapid distillation of volatile components and improving the purity of the distillation products of volatile components. In addition, the utility model greatly reduces the height of the distillation tower, eliminates multiple tower plates, and a large number of components such as bubble caps, float valves, and float tongues, simplifies the equipment structure, and saves equipment manufacturing and installation costs. The utility model changes the traditional distillation tower structure and has entered the design stage.

Claims

1. An atomizing distillation device, comprising a distillation tower, a reboiler, and a condenser; characterized in that: The distillation tower is divided into an independent distillation chamber (1), a distillation chamber (2), and a stripping chamber (3); the outer side of the distillation chamber (1) wraps a heating chamber I (13), and a liquid return atomizer (14) is arranged inside; the liquid return atomizer (14) is connected to a volatile steam pipe (12) and a liquid return pipe (18), the volatile steam pipe (12) is connected to the distillation chamber (2), and the liquid return pipe (18) is connected to a condenser; the condenser is connected to the top of the distillation chamber (1) through a gas phase pipe (15), and a gas phase pump (16) is arranged on the gas phase pipe (15); the volatile steam pipe (12) and the liquid return pipe (18) are respectively provided with a volatile steam pump (11) and a liquid return pump (17).

2. The atomizing distillation device according to claim 1, characterized in that: The outside of the distillation chamber (2) is wrapped with a heating chamber II (25), in which a raw material liquid atomizer (23) and a residual liquid pipe (21) are arranged; the raw material liquid atomizer (23) is connected to a feed pipe (22) and a mixed steam pipe (27), the mixed steam pipe (27) is connected to the distillation chamber (3), and a mixed steam pump (26) is arranged on the mixed steam pipe (27); a float valve is arranged at the bottom end of the residual liquid pipe (21).

3. An atomization distillation device according to claim 2, characterized in that: The stripping chamber (3) is surrounded by a heating chamber III (33) on the outside, and a volatile liquid atomizer (32) is arranged inside; the volatile liquid atomizer (32) is connected to a steam pipe (36) and a volatile liquid pipe (31); the volatile liquid pipe (31) is connected to the bottom of the distillation chamber (2); the steam pipe (36) is connected to the top of a reboiler, and a steam pump (35) and a regulating valve are arranged on the steam pipe (36); the reboiler is connected to the bottom of the stripping chamber (3) through a liquid phase pipe (34).

4. The atomizing distillation device according to claim 3, characterized in that: The liquid return atomizer (14), the raw liquid atomizer (23), and the volatile liquid atomizer (32) have the same structure, and include a steam ring pipe (41), a liquid ring pipe (42), and a nozzle (7); the steam ring pipe (41) is connected to the volatile steam pipe (12), or the mixed steam pipe (27), or the steam pipe (36), and the corresponding liquid ring pipe (42) is connected to the liquid return pipe (18), or the feed pipe (22), or the volatile liquid pipe (31).

5. The atomizing distillation device according to claim 4, characterized in that: The nozzles (7) are evenly distributed on the steam ring pipe (41) and the liquid ring pipe (42), and include a steam riser (71), a liquid riser (72), a threaded ring (73), a steam spray disc (74) and a fixing rod (77); the steam riser (71) is connected to the steam ring pipe (41), the liquid riser (72) is connected to the liquid ring pipe (42), and the steam riser (71) is sleeved in the liquid riser (72); a steam spray disc (74) is provided at the end of the steam riser (71), the steam spray disc (74) is fixedly connected to the threaded ring (73) via a fixing rod (77), and the threaded ring (73) is threadedly connected to the end of the liquid riser (72).

6. The atomization distillation device according to claim 5, characterized in that: The steam spray plate (74) is a spherical or ellipsoidal surface, which cooperates with the arc surface of the inner edge of the end of the steam riser (71) to form a slit-shaped steam spray port (75). The steam spray port (75) cooperates with the liquid spray port (76) at the end of the liquid riser (72).

7. The atomizing distillation device according to claim 4, characterized in that: A pre-rectification chamber (19) is arranged between the rectification chamber (1) and the distillation chamber (2); a pre-rectification atomizer is arranged in the pre-rectification chamber (19), and the structure of the pre-rectification atomizer is consistent with that of the three atomizers; the liquid ring pipe (42) is connected to the bottom of the rectification chamber (1), and the steam ring pipe (41) is connected to the distillation chamber (2); and the residual liquid pipe (21) is connected to the distillation chamber (2) and the pre-rectification chamber (19).

8. The atomization distillation device according to claim 7, characterized in that: A pre-stripping distillation chamber (37) is arranged between the distillation chamber (2) and the stripping chamber (3); a pre-stripping atomizer is arranged in the pre-stripping distillation chamber (37), and the structure of the pre-stripping atomizer is consistent with that of the three atomizers. The liquid ring pipe (42) is connected to the bottom of the distillation chamber (2), the steam ring pipe (41) is connected to the stripping chamber (3), and the residual liquid pipe (21) is connected to the pre-stripping distillation chamber (37) and the pre-rectification chamber (19).

9. The atomization distillation device according to claim 3, characterized in that: A gas-liquid separator (9) is arranged in the three chambers of the rectification chamber (1), the distillation chamber (2) and the stripping chamber (3). The gas-liquid separator (9) is arranged above the atomizer of each chamber and below the gas extraction port.

10. The atomization distillation device according to claim 1, characterized in that: The rectification chamber (1), the distillation chamber (2) and the stripping chamber (3) are separately arranged.

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