Advanced control methods for evaporation units
By using ultrasonic-controlled sound or vibration to adjust energy input in evaporation units, the method addresses slow response times, stabilizing and optimizing output flow, achieving rapid parameter adjustments and enhancing productivity by up to 20%.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-12-19
- Publication Date
- 2026-03-25
AI Technical Summary
Existing evaporation units face challenges in stabilizing and optimizing output flow due to slow response times in measuring parameters like temperature, composition, and viscosity, leading to fluctuations in product quality and reduced productivity.
A method involving ultrasonic-controlled sound or vibration is applied to evaporation units to adjust energy input, combining heat and ultrasonic waves, with a control algorithm that accounts for fast ultrasonic response times and dead times of measuring devices to stabilize and optimize output flow.
The method achieves rapid adjustments to achieve desired quality parameters in the liquid output stream within 60 seconds, stabilizing the evaporation process and increasing productivity by up to 20%, reducing variations from 3% to 0.5%, and maintaining a stable state up to 119.5% +/- 0.5%.
Smart Images
Figure 2026053483000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an advanced control method including a high-speed response method for stabilizing, optimizing and / or maximizing the output flow of an evaporation unit through ultrasonic-controlled sound or vibration applied to the evaporation unit. The present invention further provides an apparatus in which the above method is implemented, for example, an evaporation or separation unit.
Summary of the Invention
[0002] A method for controlling physical properties such as vapor pressure, viscosity, temperature, composition and / or density of the liquid fraction and / or vapor fraction of the output stream of an evaporation unit, comprising: a. Providing a set value for the physical properties of the liquid fraction of the output stream of the evaporation unit and / or the vapor fraction of the output stream; b. Measuring one or more of the physical properties of the liquid fraction of the output stream of the evaporation unit and / or one or more of the physical properties of the vapor fraction of the output stream; c. Comparing the given set value and the measured value of the physical properties of the liquid fraction of the output stream of the evaporation unit and / or the physical properties of the vapor fraction of the output stream; d. Adjusting the energy input of the vaporization input, which is a combination of heat and ultrasonic waves, to adjust the physical properties of the liquid fraction of the output stream of the evaporation unit and / or the physical properties of the vapor fraction of the output stream to match the set value. A method comprising:
[0003] In particular, an object of the present invention is to provide a method for adjusting / controlling the vapor pressure and / or viscosity of the liquid output stream M3 of the evaporation unit 10, the method comprising: a. Providing a set value S4 for the vapor pressure and / or viscosity of the liquid output stream M3; b. Measuring the vapor pressure and / or viscosity Q4 of the liquid output stream; c. Comparing the given set value and the measured value of the vapor pressure and / or viscosity of the liquid output stream; d. Adjusting the energy input of the vaporization input, which is characterized by a combination of heat A1 and ultrasonic I1, to adjust the vapor pressure and / or viscosity of the liquid output stream to match a set value, Includes.
[0004] In one embodiment of the method according to the present invention, the evaporation unit is selected from a heat exchanger, a distillation column or a part thereof, a falling membrane type apparatus, a forced circulation heat exchanger, a rising membrane type apparatus, a thermal siphon, and the like.
[0005] In another embodiment of the method according to the present invention, comparing a setpoint with a measured value includes using a neural network. In further embodiments, as detailed below, the comparison includes calculating or predicting the physical properties of the stream (see below).
[0006] In addition to the product parameters of the liquid output stream M3, the method may also include measuring the characteristics of one or more of the different product streams across the evaporator unit, for example, the supply stream M0, the vapor output stream M2, the heat input stream A1, the vapor characteristics Q5 in the upper section or heating section 20 of the evaporator unit, and the separated vapor-liquid characteristics Q6 in the lower section 30 of the evaporator unit. Thus, in one embodiment, a method according to a different embodiment of the present invention includes measuring the quality parameters (also referred to as characteristics) of the heat input stream A1. In another embodiment, a method according to the present invention includes measuring the quality parameters (also referred to as characteristics) of the supply stream M0 to the evaporator unit. In another embodiment, a method according to the present invention includes measuring the quality parameters (also referred to as characteristics) of the vapor characteristics Q5 in the upper part of the evaporator unit. In another embodiment, a method according to the present invention includes measuring the quality parameters (also referred to as characteristics) of the separated vapor-liquid Q6 in the lower section of the evaporator unit. In another embodiment, a method according to the present invention includes measuring the quality parameters (also referred to as characteristics) of the vapor output stream M2. In another embodiment, the method according to the present invention includes measuring at least two, three, four, or all of the quality parameters (also referred to as characteristics) from a stream selected from a supply stream M0, a steam output stream M2, a heat input stream A1, a steam characteristic Q5 in the upper section or heating section of the evaporator unit, and a separated steam-liquid Q6 in the lower section of the evaporator unit.
[0007] The methods provided herein can be applied to any evaporation or separation unit in which liquid-liquid or gas-liquid mass transfer occurs. This may include, for example, removing a solvent from a mixture or, in the case of an equilibrium reaction, removing a product. Possible examples of solvent removal will be described in detail below, but in a preferred embodiment, the method can be applied when removing water by a condensation reaction, particularly by an endothermic oligomerization reaction, more specifically by an endothermic oligomerization reaction of an oxoacid, and even more specifically by an endothermic oligomerization reaction of phosphoric acid, as schematically shown in Figure 1.
[0008] All of the above implies that the supply stream is subjected to mass transfer within the evaporation / separation unit. Therefore, in one embodiment, the supply stream contains reactants that undergo condensation reactions within the evaporation unit. In a particular embodiment, the condensation reaction is an endothermic oligomerization reaction, more specifically, an endothermic oligomerization reaction of an oxoacid, and even more specifically, an endothermic oligomerization reaction of phosphoric acid.
[0009] In different embodiments of the method according to the present invention, quality parameters (also referred to herein as characteristics) are determined for at least the liquid output stream M3, and optionally for at least two, three, four, or all of the streams selected from the supply stream M0, the vapor output stream M2, the heat input stream A1, the vapor characteristics Q5 in the upper or heating section of the evaporator unit, and the separated vapor-liquid Q6 in the lower part of the evaporator unit. For each of the above streams through the entire evaporator unit, the quality parameters include at least one parameter selected from the group consisting of composition, temperature, vapor pressure, density, flow rate, and viscosity. In the first embodiment, if the quality parameter Q4 of the liquid output stream M3 is compared with a set value S4 for that stream and the energy input is adjusted based thereon, this adjustment of the energy input can be refined based on a comparison of the measured quality parameters of the remaining streams with the set values for each of these streams. Therefore, in one embodiment, the method according to the present invention further includes determining quality parameters for at least two, three, four, or all of the streams selected from the supply stream M0, the steam output stream M2, the heat input stream A1, the steam characteristics Q5 in the upper or heating section of the evaporator unit, and the separated steam-liquid Q6 in the lower part of the evaporator unit; comparing said quality parameters with set values for at least two, three, four, or all of the streams selected from the supply stream M0, the steam output stream M2, the heat input stream A1, the steam characteristics Q5 in the upper or heating section of the evaporator unit, and the separated steam-liquid Q6 in the lower part of the evaporator unit; and using the results of this comparison as further input when adjusting the energy input in the evaporator unit. In a particular embodiment, the results of the above comparison (which may be more) are input to a control module 40 that manages the energy input to the evaporator unit, i.e., the heat input stream A1 and the ultrasonic vibration generators (which may be more) G1 and / or G2.In one embodiment, the heat input stream A1 is maintained at a higher or lower level, and the change in energy input is driven by ultrasonic vibration generators G1 and / or G2. In such a configuration, a fast response to changes in the quality parameters of the liquid output stream M3 can be achieved. Thus, in this method, the adjustment of the energy input is done by increasing or decreasing the ultrasonic input to the vaporization unit.
[0010] One of the advantages of the method according to the present invention relates to a fast response using ultrasound as one of the energy inputs. The response time of the energy input is even faster than the ability to measure properties such as temperature and / or composition and / or viscosity and / or degree of polymerization of the liquid output stream. As a result, in certain embodiments of the present invention, in the comparison of measured values with setpoints, parameters with slow response times, such as temperature, composition, viscosity and / or degree of polymerization, are adjusted by the control algorithm 50 taking into account the fast response time of the ultrasonic vibration generator(s) G1 and / or G2, the dead time of the pressure measuring device present in the evaporation unit and the correlation of the physical properties of the liquid output stream. In certain embodiments, the control algorithm includes using a neural network to predict the physical properties of the stream. This prediction is based on a value measured over time and at least correlated with the energy input of the vaporization input. In further embodiments, the prediction is based on a value measured over time and at least correlated with the energy input of the vaporization input, the dead time of the pressure measuring device present in the evaporation unit and the physical properties of the liquid output stream.
[0011] The method according to the present invention allows adjustment by ultrasonic energy input to reach desired quality parameters of a liquid output stream, such as a given operating pressure and a desired temperature at a given composition of the liquid output stream, in less than 60 seconds.
[0012] The following will refer specifically to the drawings, but it is emphasized that the descriptions provided are illustrative and intended solely as a descriptive discussion of various embodiments of the present invention. These drawings are presented to provide what is considered to be the most useful and simplest explanation of the principles and conceptual aspects of the present invention. In this regard, no further details of the structural aspects of the present invention beyond those necessary for a basic understanding of the present invention are to be shown. This description, together with the drawings, will make to those skilled in the art how several embodiments of the present invention can be actually implemented. [Brief explanation of the drawing]
[0013] [Figure 1] This is a schematic diagram of the reaction in a thermal conversion system that relies on the endothermic oligomerization / condensation reaction of orthophosphate / pyrophosphate with water removal, and the exothermic hydrolysis / solvation reaction of polyphosphate with water. [Figure 2] This is a schematic diagram of an advanced control system for an evaporation unit according to the present invention, which comprises ultrasonic vibration generators G1 and G2, and a control module 40 that receives measured values Q1 to Q6 of the input flows M0 and M1 and output flows M2 and M3 of the evaporation unit. The measured values are compared by the control module 40 with set values S1 to S6, and the energy input to the evaporation unit is set as a combination of heat input A1 and input parameters I1 and I2 to the ultrasonic vibration generators G1 and G2. In an exemplary embodiment, the evaporation unit is a fall-membrane type facility M1 having a heating section 20 at the top of the evaporation unit and a vapor-liquid separation section 30 at the bottom, producing a vapor fraction (e.g., solvent vapor) M2 and a liquid fraction (e.g., concentrated or polymerized flow of the supply stream M0) M3 as output flows. Parameters that are measured and set at different locations include, but are not limited to, composition, flow rate, temperature, pressure, density, and viscosity. [Modes for carrying out the invention]
[0014] The present invention provides a control method including a high-speed response method for stabilizing, optimizing, and / or maximizing the output flow of an evaporation unit via ultrasonically controlled sound or vibration applied to the evaporation unit.
[0015] A schematic diagram of an evaporation unit including such a control method is shown in Figure 1. The following can be observed: A supply stream M0 having supply stream characteristics Q1 that need to be handled in the evaporation or separation unit 10, i.e., a mixture (which may be homogeneous or heterogeneous) in which one or more components need to be evaporated and / or separated from other components (which may be more). These components that need to be evaporated or separated from other components include any type of component that has a higher vapor pressure or fugacity than other components under evaporation conditions across the evaporation unit, including evaporation conditions in the gas phase Q5 and / or the liquid phase Q6 of the evaporation. These may also be products generated by any type of physicochemical reaction in the evaporation unit, other than or the same as those present in the input stream. These components that need to be evaporated or separated from other components include any type of component whose vapor pressure is the same as any other component under evaporation conditions across the evaporation unit, including evaporation conditions in the gas phase Q5 and / or liquid phase Q6 of the evaporation unit. This may also be products generated in the evaporation unit, other than or the same as those present in the input stream. • A liquid output stream M3 arriving directly from the evaporation unit without being subjected to any other process steps. The characteristics Q4 of this liquid output stream (e.g., composition, temperature, pressure, viscosity, conductivity, mass flow rate, density, etc.), as shown in Figure 1, can be determined by direct measurement or after being subjected to other process steps, such as, but not limited to, further evaporation, cooling, heating, or reaction. • A vapor output stream M2 arriving directly from the lower section 30 of the evaporation unit without being subjected to any other process steps. The characteristics Q3 of this vapor output stream (e.g., composition, temperature, pressure, viscosity, conductivity, mass flow rate, density, etc.), as shown in Figure 1, can be determined by direct measurement or after being subjected to other process steps such as, but not limited to, condensation, cooling, heating, or reaction. • The vapor properties Q5 in the upper section of the evaporation or separation unit (typically also referred to as the heating section 20), i.e., the section through which the supply stream receives energy input, for example, through a flowing membrane configuration M1. The vapor properties in this section (e.g., composition, temperature, pressure, viscosity, conductivity, mass flow rate, density, etc.) as shown in Figure 1 can be obtained by direct measurement or after being subjected to other process steps such as, but not limited to, condensation, cooling, heating, or reaction. The properties Q6 of the separated vapor-liquid 60 in the lower section 30 of the separation unit (typically referred to as the concentration and separation section). The properties Q6 of the separated vapor-liquid 60 present in the concentration and separation section as shown in Figure 1 (e.g., composition, temperature, pressure, viscosity, conductivity, mass flow rate, density, etc.) can be obtained by direct measurement or after being subjected to other process steps such as, but not limited to, condensation, cooling, heating, or reaction. Heat input A1 in the concentration / separation section coming from a stream having characteristic Q2 for the heating section, for example, steam in cooling, condensing and / or supercooling, heat transfer oil in cooling, water in cooling, organic vapor in condensing, organic liquid in cooling, inorganic liquid in condensing or cooling, any kind of vapor in condensing and / or supercooling, any kind of liquid in cooling, etc. In the drawings, a distinction is made between measured values and desired values, i.e., setpoints. Setpoints (there may be multiple) are generated by an intelligent control method (there may be multiple) or an intelligent control algorithm (there may be multiple), or can be set manually or automatically by an operator of such a unit. Accordingly, in one embodiment, the unit includes a user input interface 70 for setting setpoints for each of the characteristics described herein, namely, a setpoint S1 for the supply stream characteristics, a setpoint S2 for the heat input characteristics, a setpoint S3 for the steam output stream characteristics, a setpoint S4 for the liquid output stream characteristics, a setpoint S5 for the steam characteristics in the heating section of the evaporation unit, and a setpoint S6 for the separated steam-liquid characteristics. In another embodiment, the unit includes a control module 40, in particular an intelligent control module, that enables automatic setting of setpoints. The unit is characterized by comprising at least one ultrasonic vibration generator G1, G2 that enables rapid changes in the energy input to the evaporation unit and thus provides improved control over the desired output of the evaporation unit.
[0016] The need to improve control over the desired output of an evaporation unit stems from the fact that all streams in industrial equipment undergo some kind of continuous fluctuation. These fluctuations can be changes in flow, composition, temperature, pressure, viscosity, conductivity, density, capacitance, magnetic properties, or any other parameter. To maintain the desired output, these changes necessitate continuous adjustment of the conditions within the evaporation unit, • All measuring devices have a dead time; that is, there is a time elapsed between the change in a parameter and the measurement taken by the measuring device. For pressure devices, typically, this is within the range of about a few seconds, and for temperature measurements, it is within the range of about a few minutes. Therefore, in existing equipment, control algorithms that respond to changes typically have a feed-forward that incorporates changes to pressure faster than changes to temperature, such that the correlation between temperature and pressure is correlated by vapor pressure equilibrium generally. · Changes in composition are very often monitored only indirectly through changes in pressure and temperature. Both changes are correlated to changes in composition such that the vapor pressures of different compositions change accordingly.
[0017] It is clear that changes in composition will affect the viscosity, density, conductivity, etc. of the liquid output stream. And for most industrial processes, this is a major determinant of the product quality that should be kept constant. Among others, but not limited to, online measurements of direct and important product and / or process parameters to lead to a certain output quality are carried out worldwide across the process industries. Considering that most control algorithms affect the output quality when changing the parameters of the input flow Q1 as in the example of the present inventors shown in FIG. 1, changes to operating conditions Q5 and Q6, etc. are made to the equipment to lead towards a stable output quality. However, the most widely used pressure and temperature measurements take a reaction time of several minutes to lead to the product quality, and therefore, ultimately the product quality still changes.
[0018] In industry and its processes, it is widely known that the higher the degree to which equipment can reach its limits and further its maximum productivity, the more it can be controlled in a continuous and stable manner with better quality without large fluctuations. Productivity can mean many things, for example, but not limited to, the production rate per hour, the production rate per day, any output production flow rate, but can also mean the degree of polymerization as a function of the output rate, the maximum viscosity that can be processed, the temperature difference in a heat exchanger, etc.
[0019] Since certain research has been conducted and published, reference is made to the background regarding the ultrasonic improvement of mass transfer in liquid-liquid interactions. The literature mentions improvements of up to tenfold in mass transfer in liquid-liquid interactions (These de Frederic Laugier, LES ULTRASONS EN PROCEDES POLYPHASIQUES: TRANSFERT GAZ-LIQUIDE ET REACTION LIQUIDE-LIQUIDE, October 30 2007) and even faster removal of vapors from liquid mixtures or streams. However, based on current research, it is unclear whether the quantitative effect of ultrasound (US) on evaporation for specific cases will be as expected.
[0020] On the other hand, the qualitative effect is known. That is, the response time of US applied to equipment where evaporation occurs is extremely short. Therefore, if there is a beneficial effect on evaporation, when US is applied, relatively large amounts of liquid will evaporate from the mixture in less than a few seconds.
[0021] Therefore, Caloritum has conducted its own research here and discovered the optimal operating conditions in an evaporation unit that uses US to evaporate the solvent from the mixture. Hereinafter, it is claimed that a new method has been discovered and created to make the process in the output liquid stream more stable, and that the process has been pushed to its productivity limit in a wide range of applications.
[0022] Test setup · An evaporation unit that evaporates water from phosphoric acid and water was operated at its maximum productivity. During the test period, 97% was in a steady state with fluctuations of + / - 3%. Ultrasound was applied to the evaporator at a rate ranging from 50% to 100% of its productivity. This corresponds to a 10% to 20% increase in evaporation rate. In other words, applying ultrasound increased the heat absorption due to water evaporation by 10% to 20%. In other words, the maximum productivity was 107% + / - 3% to a maximum of 117% + / - 3%. Compared to changes in steam input that increase or decrease evaporation rate, the application of ultrasound affects the evaporation of water due to the endothermic oligomerization reaction of phosphoric acid within a few seconds, i.e., within 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, and 20 seconds.
[0023] This novel method of applying ultrasonic vibrations as an energy input to the heating section of an evaporation or separation unit has been shown to narrow the spread from 3% to 0.5%, thereby reducing continuous changes / variations in output quality. This is because a rapid response to evaporation is carried out due to US generation on the instrument, and the correlation of physical properties, such as vapor pressure as a function of temperature and composition of the mixture, is taken into account, as well as the different dead times of different measuring devices. Therefore, by incorporating a fast US response into the control algorithm, production capacity can be operated in a stable state of up to 119.5% + / - 0.5% over the long term. Thus, the object of the present invention is to provide an advanced control method for stabilizing, optimizing and / or maximizing the output flow of an evaporation unit by using a heat input stream in combination with an ultrasonic vibration generator, the method including a control algorithm that takes into account the correlation of the fast response time of the ultrasonic vibration generator, the dead time of the pressure measuring device present in the evaporation unit, and the physical properties of the liquid output stream.
[0024] The configuration of adding a US as part of the heating section to control the physical properties of the liquid fraction and / or vapor fraction of the output stream of the evaporation unit is contrary to current US applications, such as in cooling towers, e.g., Chinese Utility Model Registration No. 201059884 or Chinese Published Patent No. 102072685. In these documents, the US is used to facilitate water mist condensation in the hot supply stream of a cooling tower, but unlike the present invention, it is not connected to the energy input to the evaporation unit.
[0025] conclusion In the test setup (see schematic diagram in Figure 1), a control method implemented as an algorithm using an ultrasonic generator, applied to equipment for evaporation or liquid vapor separation (also referred to as a “smart” fast response method), was found to improve the stability of the evaporation process and improve the production rate by up to 20% or more (this may vary depending on the specific configuration).
[0026] The present invention, for example, is not limited to, • Drip-type membrane evaporator Evaporator • Distillation equipment This can be widely implemented in process industries where liquid-to-liquid or gas-to-liquid mass transfer occurs.
[0027] Possible processes involving such mass transfer include, for example, • Acids: Hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, and many others. The process involves removing water from the acid to increase its concentration. • Removing water from alcohols such as methanol, ethanol, and propanol, without limitation. • Removing a solvent from a mixture, for example, but not limited to, removing toluene from an acid, toluene from water, toluene from an amine, aromatics from an alkene, alkenes from alkenes, or olefins from non-olefins. These are some examples.
[0028] Drawing translation Figure 1 Orthophospheric acid Pyrophospheric acid Polyphosphoric acid
Claims
1. A method for controlling the physical properties of the liquid fraction and / or vapor fraction of the output stream of an evaporation unit, such as vapor pressure, viscosity, temperature, composition and / or density, a. Setting a set value for the liquid fraction and / or vapor fraction of the output stream of the evaporation unit, b. Measuring one or more of the physical properties of the liquid fraction of the output stream of the evaporation unit, and / or one or more of the physical properties of the vapor fraction of the output stream, c. Comparing the given set value with the measured value of the physical characteristics of the liquid fraction of the output stream of the evaporation unit and / or the physical characteristics of the vapor fraction of the output stream, d. Adjusting the energy input of the vaporization input, which is characterized by a combination of heat and ultrasound, to adjust the physical properties of the liquid fraction and / or the vapor fraction of the output stream of the evaporation unit to match the set value, Methods that include...
2. The method according to claim 1, wherein the evaporation unit is selected from a heat exchanger, a distillation column or a part thereof, a forced-circulation heat exchanger, a downward-flowing membrane type equipment, an upward-flowing membrane type equipment, a thermal siphon, and the like.
3. The method according to claim 1 or 2, wherein the comparison includes predicting the effect of the energy input on the output characteristics using a neural network.
4. The method according to claim 1 or 2, wherein the comparison includes predicting the physical properties of the stream using a neural network.
5. The method according to any one of claims 1 to 4, comprising measuring the quality parameters of the heat input.
6. The method according to any one of claims 1 to 5, comprising measuring the quality parameters of the supply stream to the evaporation unit.
7. The method according to claim 6, wherein the supply stream includes reactants that have undergone a reaction in the evaporation unit.
8. The method according to claim 7, wherein the supply stream includes reactants that undergo a condensation reaction in the evaporation unit.
9. The method according to claim 8, wherein the condensation reaction is an endothermic oligomerization reaction, particularly an endothermic oligomerization reaction of an oxo acid.
10. The method according to claim 8, wherein the condensation reaction is an endothermic oligomerization reaction of phosphoric acid.
11. The method according to claim 6 or 7, wherein the quality parameter includes at least one parameter selected from the group consisting of composition, temperature, vapor pressure, density, flow rate, and viscosity.
12. The method according to any one of claims 1 to 11, wherein the adjustment of the energy input is an increase or decrease in the ultrasonic input to the vaporization unit.