RU236610U1 - Dynamic packing for heat and mass transfer processes - Google Patents

Abstract

The utility model relates to packing used in column apparatuses, primarily for carrying out heat and mass exchange processes, and can find application in the chemical, petrochemical, power, metallurgy, food, pharmacological and other industries. Dynamic packing for heat and mass exchange processes, made in the form of bodies of revolution located one inside the other and connected, made perforated in the form of Raschig rings made of polymeric materials, the inner body of revolution is located at a distance from the outer body of revolution, wherein the ratio of the outer diameter of the inner ring to the inner diameter of the outer ring is equal to 0.7, wherein the outer and inner rings are connected to each other by means of two conical springs of variable stiffness made of polymeric materials, wherein the upper and lower ends of the inner ring are connected to the spring coils of the smallest diameter, and the spring coils of the largest diameter are connected to the outer ring at its upper and lower ends, respectively. The technical result of the proposed design of dynamic packing for heat and mass transfer processes is the intensification of heat and mass transfer processes.

Description

The utility model relates to packings used in column apparatuses, primarily for carrying out heat and mass exchange processes of absorption, extraction, rectification, and can find application in the chemical, petrochemical, energy, metallurgy, food, pharmacological and other industries, as well as in environmental processes for separating oil sludge, waste hydrocarbon solutions, solvents and other substances for their separation and purification at the molecular level.

A nozzle for heat and mass exchange processes is known, made in the form of bodies of revolution located one inside the other and connected by means of two springs, having the shape of cylindrical surfaces, and the inner body of revolution is located at a distance from the outer body of revolution, made in the form of Raschig rings and laid in an orderly manner in rows, wherein the ratio of the outer diameter of the inner body of revolution to the inner diameter of the outer ring is equal to 0.7, and the ratio of their heights lies within the limits:

where h and H are the heights of the inner and outer rings, respectively, in m, and the inner body of revolution is made uniformly perforated with positive buoyancy in the working fluid, connected to the outer ring on the lower ring. (Patent for Utility Model of the Russian Federation No. 162267, IPC: B01J 19/30, published on 10.06.2016).

The reasons preventing the achievement of the specified technical result include insufficient intensity of heat and mass exchange processes and relatively low productivity associated with the narrow dynamic range of oscillations of the internal body (turbulator) and the need for spatial orientation of the packing elements, as well as the complexity of manufacturing due to the connection of the external and internal bodies of rotation with each other by means of several springs.

A nozzle for heat and mass exchange processes is known, made in the form of bodies of revolution arranged one inside the other and connected, having the shape of cylindrical surfaces, the inner body of revolution is located at a distance from the outer body of revolution, characterized in that the bodies of revolution are made in the form of Raschig rings and are connected at the end parts by means of at least two springs, wherein the ratio of the outer diameter of the inner ring to the inner diameter of the outer ring is equal to 0.7, and the ratio of their heights lies within the limits:

where h and H are the heights of the inner body of revolution and the outer ring, respectively, in m (Patent for Utility Model of the Russian Federation No. 148733, B01J 19/00, published on 10.12.2014)

The disadvantage of this packing for heat and mass exchange processes is the insufficient (low) intensity of heat and mass exchange processes and relatively low productivity associated with the narrow resonant range of oscillations of the inner body (turbulator), the complexity of manufacturing due to the connection of the outer and inner bodies of rotation with each other by means of several springs located at an angle relative to the direction of oscillations of the inner body and the spatial mismatch of the directions of oscillations of the inner body and springs, which greatly narrows the working range of oscillations, and also forms the condition for the need for an ordered spatial orientation of the packing elements.

The closest technical solution in terms of the set of features to the claimed object and adopted as a prototype is a nozzle for heat and mass exchange processes, made in the form of bodies of revolution located one inside the other and connected, made in the form of Raschig rings, the inner body of revolution is located at a distance from the outer body of revolution, while the ratio of the outer diameter of the inner ring to the inner diameter of the outer ring is 0.7, and the outer and inner rings are made perforated and connected to each other by means of a conical spring of variable stiffness, while the inner ring is connected by its upper end to the lower smallest turn of the spring, and the upper turn of the spring of variable stiffness is connected to the outer ring at its upper end. (Patent for Utility Model of the Russian Federation No. 200778, B01J 19/30, published on 11.11.2020)

The reasons that prevent the achievement of the specified technical result include the low efficiency of mass exchange processes and relatively low productivity associated with the narrow resonant range of oscillations of the internal body (turbulator), the need to use springs of increased rigidity to fix the weight of the internal body of rotation (for stable spatial orientation of the internal body of rotation), which greatly narrows the working range of oscillations of the spring, as well as the need for spatial orientation of the packing elements, since with a disordered arrangement, there will be a redistribution of the load and a decrease or complete cessation of oscillatory movements.

The technical result of the proposed design of dynamic packing for heat and mass transfer processes is the intensification of heat and mass transfer processes.

The technical result is achieved in that the dynamic nozzle for heat and mass exchange processes is made in the form of bodies of revolution located one inside the other and connected, made perforated in the form of Raschig rings made of polymeric materials, the inner body of revolution is located at a distance from the outer body of revolution, wherein the ratio of the outer diameter of the inner ring to the inner diameter of the outer ring is equal to 0.7, and the outer and inner rings are connected to each other by means of two conical springs of variable stiffness made of polymeric materials, wherein the inner ring is connected with the coils of the springs of the smallest diameter by the upper and lower ends, and the coils of the springs of the largest diameter are connected to the outer ring at its upper and lower ends, respectively.

The production of rings and springs of dynamic packing for heat and mass exchange processes from polymeric materials imparts greater chemical resistance and specific strength to the packing elements (than that of metal materials of springs and external bodies), which is especially important when cleaning gas emissions and products of mass exchange processes from sulfur compounds and acid vapors in the chemical, petrochemical, oil and gas refining and other industries. Acid resistance and resistance to sulfur compounds will ensure the preservation of the surface properties of dynamic packing elements, will allow them to exhibit stable dynamic properties during the operation of mass exchange equipment, will ensure stable heat and mass exchange processes and the stability of optimal hydrodynamic operating modes of mass exchange packed columns, which in turn will ensure high rates of capture of extractable components from gas-phase emissions (using the absorption process as an example) and will increase the productivity of mass exchange devices.

The connection of the outer and inner Raschig rings made of polymeric materials by means of conical springs of variable stiffness, also made of polymeric materials, in such a way that the upper and lower ends of the inner ring are connected to the spring turns of the smallest diameter, and the spring turns of the largest diameter are connected to the outer ring at its upper and lower ends, respectively, will increase the reliability of the packing and ensure resonant oscillations of the inner packing element made in the form of a Raschig ring made of a polymeric material in a wide range of gas (steam) and liquid phase velocities, which will lead to the stability of the dynamic properties of the inner packing elements, regardless of the spatial position of the packing elements when installed in the pile, which leads to a significant intensification of heat and mass exchange processes. Such fastening of the inner Raschig ring made of polymeric materials makes it possible to install low-stiffness springs made of polymeric materials, which increases the sensitivity of the internal dynamic elements at relatively low local flow rates of the gas (liquid) phase. That is, dynamic properties will manifest themselves at significantly lower local flow rates of the gas (liquid) phase, which leads to a significant intensification of heat and mass exchange processes under the same conditions.

Fig. 1 shows a general view of a dynamic packing for heat and mass transfer processes.

The dynamic packing for heat and mass exchange processes consists of an outer Raschig ring 1 with an inner diameter D and an inner Raschig ring 2 with an outer diameter d, made of polymeric materials. The ratio of the outer diameter d of the inner ring 2 to the inner diameter D of the outer ring 1 is 0.7. The outer 1 and inner 2 Raschig rings are made perforated and connected to each other by means of two conical springs 3 of variable rigidity, made of polymeric materials, so that the inner Raschig ring 2 is connected with the upper and lower ends of the conical springs 3 of the smallest diameter, and the turns of the springs 3 of the largest diameter are connected to the outer Raschig ring 1 at its upper and lower ends, respectively.

Dynamic packing for heat and mass transfer processes works as follows.

Heat and mass transfer packing elements can be poured in bulk or laid in ordered rows, depending on the requirements of a specific process and apparatus, and the overall dimensions of the packing elements.

The packing is irrigated with liquid from above, and gas (steam) is supplied from below in cases where this packing is used for absorption or rectification processes. In case of liquid packed extraction, the extractant and solution can implement various flow patterns, counter-current or direct current, through the packing. The ends of the outer Raschig rings 1 do not interact with the ends of the inner Raschig rings 2, and the latter can freely oscillate on springs 3 inside the outer rings 1. Under the action of the gas (steam) flow or the pulse of oscillations of the liquid column (packed pulsating extraction), each inner Raschig ring 2 performs resonant oscillations due to its fastening on conical springs 3, which lead to local turbulence within each packing element, are transmitted by emerging gas bubbles, lead to the activation of washing of liquid films covering the inner packed bodies, or activate mutual mixing of the extraction products. This effect leads to intensification of heat and mass exchange at the interface of the gas (steam) and liquid phases (for absorption and rectification). Diffusion processes and mutual mixing of liquid-phase extraction products are also activated, which generally leads to intensification of heat and mass exchange.

An example of the operation of a dynamic packing for heat and mass transfer processes.

The mixture of the separated components "heptane-hexane" is fed to the feed section of the rectification column, steam is fed from the bottom of the rectification column and passes through layers of dynamic packed elements spatially oriented in ordered rows. The flow of the feed mixture and phlegm passes through the elements of the dynamic packing and is broken up into elementary streams and moves along the axis of the column, contacting with the vapor-phase flow in various hydrodynamic modes (in the range from film to developed emulsification beyond the phase inversion point). The flow of the feed mixture and phlegm, passing through the internal Raschig rings 2, which are fixed on springs 3 inside the external Raschig rings 1, activates the dynamic and resonant properties of the packed elements. In this case, each internal Raschig ring 2 performs resonant oscillations due to its fixation on conical springs 3, which lead to local turbulization within each packed element. Which in turn provides increased retention capacity for liquid and vapor phases and an increase in the total dynamic contact surface of the mass exchange product phases in all contact elements of the packed bed. This effect allows, with equal productivity, to reduce steam consumption in the column with a smaller packing volume, confirming the intensification of heat and mass exchange processes carried out using the claimed packing, which leads to savings in operating costs.

Table 1 presents comparative indicators of a packed rectification column with a typical and declared packing design for heat and mass transfer processes.

Table 1

Parameter name Dimensionality Designation Size Standard nozzle Claimed nozzle 1. Productivity of the initial mixture kg/hour G _f 6000 6000 2. Porosity of the nozzle m ³ /m ³ ε 0.735 0.635 3. Specific surface area of the packing m ² /m ³ σ 110 200.5 4. Optimal reflux ratio - Ro 2.08 1.79 5. Total volume of the nozzle m ³ V _k 9.1 6 6. Steam consumption kg/hour G 6616.3 5996.9 7. Total cost of operation RUB/year E ₀ 6.74⋅10 ⁶ 4.97⋅10 ⁶ 8. Annual energy costs kW⋅hour E _n 2445 1255

Thus, the connection of the outer 1 and inner 2 Raschig rings made of polymeric materials by means of two conical springs 3 of variable rigidity, also made of polymeric materials, in such a way that the inner ring 2 is connected with the turns of the spring 3 of the smallest diameter by its upper and lower ends, and the turns of the spring 3 of the largest diameter are connected with the outer ring 1 at its upper and lower ends, respectively, will provide resonant oscillations of the inner packing element made in the form of a Raschig ring in a wide range of velocities of the gas (steam) and liquid phases, which will lead to the stability of the dynamic properties of the inner packing elements regardless of the spatial position of the packing elements when installing them in the apparatus, which leads to a significant intensification of heat and mass exchange processes. Such fastening of the inner Raschig ring makes it possible to install springs of low rigidity, which increases the sensitivity of the internal dynamic elements at relatively low local flow rates of the gas (liquid) phase. That is, dynamic properties will manifest themselves at significantly lower local flow rates of the gas (liquid) phase, which leads to a significant intensification of heat and mass exchange processes.

The production of rings and springs of dynamic packing for heat and mass exchange processes from polymeric materials imparts greater chemical resistance and specific strength to the packing elements (than that of metal materials of springs and external bodies), which is especially important when cleaning gas emissions and products of mass exchange processes from sulfur compounds and acid vapors in the chemical, petrochemical, oil and gas refining and other industries. Acid resistance and resistance to sulfur compounds will ensure the preservation of the surface properties of dynamic packing elements, will allow them to exhibit stable dynamic properties during the operation of mass exchange equipment, will ensure stable heat and mass exchange processes and the stability of optimal hydrodynamic operating modes of mass exchange packed columns, which in turn will ensure high rates of capture of extractable components from gas-phase emissions (using the absorption process as an example) and will increase the productivity of mass exchange devices.

Claims (1)

A dynamic nozzle for heat and mass exchange processes, made in the form of bodies of revolution located one inside the other and connected, made perforated in the form of Raschig rings made of polymeric materials, the inner body of revolution is located at a distance from the outer body of revolution, wherein the ratio of the outer diameter of the inner ring to the inner diameter of the outer ring is 0.7, characterized in that the outer and inner rings are connected to each other by means of two conical springs of variable stiffness made of polymeric materials, wherein the inner ring is connected with the spring turns of the smallest diameter by its upper and lower ends, and the spring turns of the largest diameter are connected to the outer ring at its upper and lower ends, respectively.