Integrated heat pump type low temperature circulation dryer

Abstract

The application relates to the technical field of dryers, in particular to an integrated heat pump type low-temperature circulating dryer, which comprises a dryer body, a hot air assembly, a liquid collecting assembly, a blowing assembly, an integrated heat pump dehumidification circulating assembly and a vacuum dehumidification assembly; the dryer body is sequentially composed of a base, an intermediate shell and an upper shell; the base, the intermediate shell and the upper shell are internally provided with a drying cavity; a gradually-changing air flow distribution plate is arranged in the drying cavity; micropores are arranged on the gradually-changing air flow distribution plate; the base, the intermediate shell and the upper shell are internally provided with inner walls; the outer walls of the inner walls are provided with constant-temperature heat exchange jackets; and the constant-temperature heat exchange jackets are provided with flow channels. The integrated heat pump type low-temperature circulating dryer can form a low-oxygen negative pressure space, the negative pressure condition can reduce the vaporization temperature of water, the hot air temperature of the equipment can be stably controlled in the interval of 45-60 DEG C, and the temperature interval is far lower than the softening and melting temperature of a low-eutectic system formed by the chenodeoxycholic acid and the water-containing wet product.

Description

Technical Field

[0001] This invention relates to the field of dryer technology, specifically to an integrated heat pump type low-temperature circulating dryer. Background Technology

[0002] In the pharmaceutical field, chenodeoxycholic acid, as an intermediate for steroidal drugs, has unique physicochemical properties when the wet product obtained after extraction and refining processes is hydrated. When the material coexists with free water, it forms a eutectic mixture, which softens the material and significantly lowers the melting temperature. Under conventional drying conditions, it is prone to stickiness, clumping, and melting against the wall. At the same time, this type of material has prominent heat sensitivity. Prolonged heating or excessively high local temperatures can cause side reactions such as molecular polymerization and oxidation, directly resulting in excessive levels of related substances and poor color of the finished product, which greatly reduces the product qualification rate.

[0003] Currently, the mainstream equipment used for drying this type of wet product in the industry is divided into two categories: double-cone vacuum dryers and conventional fluidized bed dryers. Both have unavoidable defects in actual mass production. Traditional double-cone vacuum dryers rely on the tank jacket for conduction heating, and heat can only be transferred to the material through the cylinder wall. The material temperature at the cylinder wall is relatively high, while the drying rate of the material in the central area of ​​the tank is slow, and there is a significant temperature difference in the overall material layer. During the rotation process, the material is continuously compacted and piled up due to its own gravity, blocking the channels for moisture diffusion. In order to achieve the qualified moisture content, the drying time must be extended, and the drying cycle for a single batch generally reaches more than ten hours. The long-term high-temperature vacuum environment will continue to intensify the polymerization reaction of chenodeoxycholic acid. The molten and agglomerated material will also adhere firmly to the inner wall of the tank, which not only increases the workload of manual cleaning, but also requires the scrapping of the adhered and agglomerated parts due to overheating, resulting in high production losses and rework costs.

[0004] Conventional fluidized bed dryers rely on large volumes of hot air to penetrate the material layer and achieve material suspension and fluidization. While this avoids the defects of material compaction and localized material blockage in double cone dryers, the equipment uses an open hot air circulation structure. Hot air carrying moisture and fine powder is directly discharged to the outside, and heat cannot be recovered, resulting in high overall energy consumption for the fan and heating unit. To maintain a stable fluidized bed state, the equipment can only be set to a fixed, constant air volume, and the air supply parameters cannot be adjusted in real time according to the dryness of the material and the thickness of the material layer. In the initial stage of feeding, the wet material has a high moisture content, and a fixed air volume is insufficient to break up the wet clumps, resulting in localized gelatinization. In the later stage of drying, when the material is almost completely dry, continuous high air velocity will carry a large amount of fine chenodeoxycholic acid powder away with the exhaust air, reducing the material yield. At the same time, dust accumulation in the workshop makes it difficult to meet the clean production standards for pharmaceuticals.

[0005] Existing drying equipment relies solely on manual experience to set process parameters such as temperature, air volume, and vacuum. There are no quantitative fluidization judgment standards or adaptive air volume adjustment logic. Operators can only manually adjust operating parameters by observing the material status on-site. The process conditions vary greatly between different operators and different production batches, resulting in significant fluctuations in the impurities and moisture content of the finished product, and poor process reproducibility. Therefore, an integrated heat pump type low-temperature circulating dryer is proposed. Summary of the Invention

[0006] One of the technical problems this application aims to solve is that existing double-cone drying, conventional boiling drying, and split-type low-temperature drying equipment cannot simultaneously meet the multiple requirements of low-temperature degradation prevention, low material loss, energy saving, quantitative and controllable process, and explosion-proof and quiet production of eutectic heat-sensitive materials such as chenodeoxycholic acid. They have multiple defects such as melting and agglomeration, increased impurities, high energy consumption, low yield, parameters relying on experience for adjustment, poor unit linkage, and insufficient safety and noise reduction of vacuum units.

[0007] To address the aforementioned technical problems, this application provides an integrated heat pump type low-temperature circulating dryer, including a dryer body, a hot air assembly, a liquid collection assembly, a blower assembly, and an integrated heat pump circulation system and a vacuum dehumidification system. The integrated heat pump circulation system includes an integrated heat pump dehumidification circulation assembly, and the vacuum dehumidification system includes a vacuum dehumidification assembly. The dryer body is composed of a base, a middle shell, and an upper shell in sequence. A drying chamber is provided inside the base, the middle shell, and the upper shell. A gradient airflow distribution plate is provided inside the drying chamber, and micropores are provided on the gradient airflow distribution plate. An inner wall is provided inside the base, the middle shell, and the upper shell, and a constant temperature heat exchange jacket is provided outside the inner wall. The constant temperature heat exchange jacket is provided with flow channels.

[0008] In some embodiments, the hot air assembly is connected to the base via a pipe 1; the liquid collection assembly is connected to the dryer body via a pipe 2, and a collection cylinder is provided at the bottom of the liquid collection assembly.

[0009] In some embodiments, the micropore opening ratio increases gradually upward from the feed inlet; the blower assembly is connected to the liquid collection assembly via pipe six, and the blower assembly also includes a blower and a chimney disposed on the blower.

[0010] In some embodiments, the vacuum dehumidification assembly is a silent explosion-proof vacuum unit, which is connected to the base through pipe five. The bottom of the base is provided with an air exchange plate, and the air exchange plate is provided with filter holes to allow airflow.

[0011] In some embodiments, a filter bag is provided on the upper housing, and pipe two is connected to pipe six via pipe three.

[0012] In some embodiments, the integrated heat pump dehumidification circulation assembly includes a pipe four communicating with the intermediate shell, a waste heat recovery heat exchanger disposed near the intermediate shell, an evaporator near the other end of the pipe four, a compressor disposed above the evaporator, an expansion valve disposed on one side of the compressor, and a condenser disposed on the other side of the compressor. The waste heat recovery heat exchanger is a duct jacketed plate heat exchange structure.

[0013] In some embodiments, the system also includes a variable frequency adaptive microfluidic air supply system, an intelligent multi-parameter collaborative control system, and a dust removal and loss prevention system; The variable frequency adaptive microfluidic air supply system uses a blower as a variable frequency stepless speed regulating air supply fan; the intelligent multi-parameter collaborative control system has two sets of quantitative calculation mathematical models built in, namely the microfluidic boundary judgment model and the multivariable air volume dynamic correction model. The dust removal and loss prevention system consists of filter bags inside the upper housing, which are used to capture fine materials entrained by the circulating airflow and return them to the drying chamber.

[0014] In some embodiments, the microfluidization boundary determination model includes a minimum fluidization velocity calculation formula and an optimal microfluidization wind speed calculation formula. Minimum fluidization rate calculation formula: ; Formula for calculating optimal microfluidization velocity: ; in: Minimum fluidization velocity, in m / s; The average particle size of the dried material is expressed in meters (m). True density of the material, in kg / m³ 3 ; Density of closed-loop hot air, unit: kg / m³ 3 ; The acceleration due to gravity is taken as 9.81 m / s². 2 ; The dynamic viscosity of the circulating hot air is expressed in Pa·s. The particle Reynolds number; The real-time optimal microfluidic velocity for the equipment is expressed in m / s. This is the vacuum low humidity correction factor, with a value range of 0.90-0.95; The terminal velocity of material particles, in m / s; During equipment operation, the real-time air supply velocity is constrained to and The low-disturbance microfluidization zone between these zones prevents material agglomeration and fine powder dust loss.

[0015] In some embodiments, the formula for the multivariable air volume dynamic correction model is: ; in: The real-time output air volume of the blower (601), in m³. 3 / h; The reference microfluidization air volume under steady-state dry material conditions, in m³. 3 / h; This is the correction factor for the moisture content of the material; This is a correction factor for the thickness of the material layer inside the drying chamber; This is the correction factor for the relative humidity inside the drying chamber; The intelligent multi-parameter collaborative control system adaptively matches three sets of correction coefficient value ranges according to different drying stages: Pre-drying high humidity stage, Take 1.10-1.20, Take a concentration of 1.05-1.10; during the intermediate constant temperature drying stage, , , All are approaching 1.0; the low-temperature phase is nearing its end. , Take 0.80-0.90.

[0016] In some embodiments, the integrated heat pump dehumidification circulation assembly forms a closed-loop circulation duct with no hot air exhaust. The hot and humid airflow discharged from the drying chamber first flows through the evaporator to condense and precipitate moisture to complete dehumidification. After dehumidification, the low-temperature airflow passes through the compressor and condenser to exchange heat and be heated to 45-60℃ low-temperature process hot air. After passing through the waste heat recovery heat exchanger, it is sent to the base to enter the drying chamber for circulation. The vacuum dehumidification component and the integrated heat pump dehumidification circulation component form a dual dehumidification coupling structure of vacuum negative pressure dehumidification and heat pump condensation dehumidification. The flow channel of the constant temperature heat exchange jacket is connected to the heat pump to recover waste heat and provide uniform auxiliary heating to the entire drying chamber, with a temperature control accuracy of ±0.5℃.

[0017] This invention has at least the following beneficial effects: 1. This equipment integrates heat pump circulation, vacuum negative pressure, microfluidic air supply, intelligent parameter control, and dust collection and recovery structure into a single sealed cavity frame to form a complete device. The entire process maintains a continuous sealed vacuum fluidized drying environment, with no continuous external air intrusion. This stable low-oxygen negative pressure space allows for the complete dehydration of wet chenodeoxycholic acid. The negative pressure condition lowers the vaporization temperature of water, and the hot air temperature during equipment operation can be stably controlled within the range of 45 to 60 degrees Celsius. This temperature range is far lower than the softening and melting temperature of wet chenodeoxycholic acid after it forms a eutectic system. The material will not soften, become sticky, clump, or stick to the walls and gelatinize during the entire drying process. The constant temperature heat exchange jacket outside the cavity relies on the heat pump to recover waste heat to achieve uniform auxiliary heating throughout the entire area. There are no local high-temperature areas, and the material will not undergo molecular polymerization and oxidation reactions due to local overheating. The increase in related substances inside the finished product can be effectively controlled, and the color and purity indicators of different batches of finished products can remain stable. This significantly reduces material loss and production time consumption caused by product rework and batch scrapping.

[0018] 2. The equipment relies on an integrated heat pump dehumidification circulation structure to construct a closed-loop hot air circuit without external exhaust. The hot and humid airflow discharged from the drying chamber is all sent into the heat pump to complete condensation, dehydration, and heat recovery. The heat released after water vapor precipitation is used again for low-temperature hot air preparation. The entire drying system does not continuously discharge hot air or heat during operation and does not require continuous consumption of fresh high-temperature heat sources. The compressor, evaporator, condenser, and waste heat recovery heat exchanger inside the heat pump work together to complete heat recycling. Compared with traditional double cone drying equipment and conventional boiling drying equipment, the heat energy consumption of the entire equipment can be significantly reduced. The matching variable frequency blower relies on a quantitative mathematical model to dynamically match the required air volume in real time, and will not maintain a constant high air volume for a long time. The energy consumption of the blower operation is reduced accordingly. The overall production energy consumption can be significantly reduced compared with traditional drying equipment, and the electricity and heat costs during the production and operation phase can be continuously reduced.

[0019] 3. The equipment is equipped with an intelligent multi-parameter collaborative control system with two built-in quantitative mathematical models that can perform real-time closed-loop calculations. During operation, it continuously collects data on the moisture content of the material inside the cavity, the thickness of the material layer, and the relative humidity inside the cavity. It determines the safe fluidization conditions by using the minimum fluidization velocity and the optimal microfluidization wind speed. Then, it automatically calculates and matches the real-time operating air volume through a multi-variable correction formula. The entire air volume adjustment process is completed autonomously by the equipment, without the need for operators to manually change the operating parameters based on on-site observation. All process adjustment logic is supported by fixed quantitative calculation standards, and there will be no human deviation in process parameters between different production batches. The drying process has good reproducibility. The equipment's built-in program can automatically switch the corresponding correction coefficient values ​​according to the three stages of pre-drying, constant temperature drying, and low temperature finishing. In the early stage of feeding, the air volume can be appropriately increased to break up wet material clumps. In the later stage of drying, the fan output air volume is automatically reduced to prevent fine powder from being carried away by the high-speed airflow.

[0020] 4. The integrated frame of the equipment incorporates a dust removal structure, and the upper shell is equipped with filter bags. Fine particles carried by the circulating airflow are completely captured by the filter material. The captured powder can fall back into the drying chamber by its own weight to continue the drying process, without being lost with the exhaust air and causing raw material loss. The overall yield of high-value chenodeoxycholic acid material is significantly improved compared to conventional open fluidized bed dryers. At the same time, the entire set of equipment is completely sealed with no dust leakage, and there will be no accumulation of raw material dust in the workshop. It can maintain a clean production environment for a long time and meet the relevant GMP production standards for pharmaceutical products.

[0021] 5. The vacuum dehumidification component of the equipment adopts a silent explosion-proof vacuum unit. The unit is directly connected to the base of the drying chamber through pipelines. The unit is equipped with a sound insulation and vibration reduction structure on the outside, which can effectively reduce the vibration and noise generated during continuous long-term operation. The motor as a whole meets the explosion-proof standards and is suitable for the explosion-proof zone production conditions of pharmaceutical intermediate workshops. The vacuum unit and the heat pump dehumidification structure form a dual dehumidification coupling mode. The water vapor inside the chamber can be removed simultaneously by vacuum pumping and heat pump condensation. The water vapor partial pressure inside the chamber is maintained at a low level, the rate of moisture migration from the inside of the material to the outside is improved, the overall drying time of a single batch of material is significantly shortened, and the total time that the material is in the heated environment is further reduced, which can reduce the probability of thermal side reactions from the time dimension. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the overall structure of the present invention. Figure 2 ; Figure 3 This is a bottom view of the overall structure of the present invention; Figure 4 for Figure 3 Sectional view of AA in the middle; Figure 5 This is a top view of the overall structure of the present invention; Figure 6 for Figure 5 BB cross-section; Figure 7 for Figure 6 Enlarged view at point C; Figure 8 for Figure 6 Enlarged view at point D; Figure 9 This is a schematic diagram of the internal structure of an integrated heat pump dehumidification circulation component.

[0023] In the diagram, 100-dryer body; 101-base; 102-intermediate shell; 103-upper shell; 104-filter bag; 105-drying chamber; 106-gradient airflow distribution plate; 107-micropores; 108-inner wall; 109-constant temperature heat exchange jacket; 110-flow channel; 111-ventilation plate; 112-filter holes; 113-feed inlet; 200-hot air assembly; 201-pipeline one; 300-liquid collection... Components; 301-Pipe 2; 302-Pipe 3; 303-Collection cylinder; 400-Integrated heat pump dehumidification circulation component; 401-Pipe 4; 402-Evaporator; 403-Expansion valve; 404-Compressor; 405-Condenser; 406-Waste heat recovery heat exchanger; 500-Vacuum dehumidification component; 501-Pipe 5; 600-Blower component; 601-Blower; 602-Chimney; 603-Pipe 6. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1, see Figures 1-9 The present invention provides a technical solution: an integrated heat pump type low temperature circulating dryer, including a dryer body 100, a hot air assembly 200, a liquid collection assembly 300, a blower assembly 600, and also includes an integrated heat pump circulation system and a vacuum dehumidification system; The integrated heat pump circulation system includes an integrated heat pump dehumidification circulation component 400, and the vacuum dehumidification system includes a vacuum dehumidification component 500. The dryer body 100 is composed of a base 101, an intermediate shell 102, and an upper shell 103 in sequence. A drying chamber 105 is provided inside the base 101, the intermediate shell 102, and the upper shell 103. A gradual airflow distribution plate 106 is provided inside the drying chamber 105. Micropores 107 are provided on the gradual airflow distribution plate 106. The base 101, the middle shell 102, and the upper shell 103 are provided with an inner wall 108. A constant temperature heat exchange jacket 109 is provided outside the inner wall 108. The constant temperature heat exchange jacket 109 is provided with a flow channel 110.

[0026] The hot air assembly 200 is connected to the base 101 through pipe 201; the liquid collection assembly 300 is connected to the dryer body 100 through pipe 301, and a collection cylinder 303 is provided at the bottom of the liquid collection assembly 300.

[0027] The porosity of the micropores 107 increases gradually from the feed inlet 113 upwards; the blower assembly 600 is connected to the liquid collection assembly 300 through the pipe 603, and the blower assembly 600 also includes a blower 601 and a chimney 602 installed on the blower 601.

[0028] Specifically, the dryer body 100 is composed of three sections: a base 101, a middle shell 102, and an upper shell 103. The three sections together form a complete enclosed space as the drying chamber 105. The segmented shell structure simplifies the installation of internal components and subsequent disassembly and cleaning operations. The segmented disassembly and assembly method reduces the volume of equipment that needs to be moved when cleaning the overall chamber, and reduces the difficulty of manual cleaning operations. After the three shell sections are sealed and spliced ​​together, they can continuously maintain a closed negative pressure state inside the chamber, providing a stable spatial foundation for low-oxygen, low-temperature fluidized drying. The drying chamber 105 is equipped with a gradient airflow distribution plate 106. Micropores 107 are opened on the surface of the gradient airflow distribution plate 106. The opening rate of the micropores 107 gradually increases from the feed inlet 113 upwards. The flow rate of hot air in different height areas is adjusted from the airflow delivery level. The low-temperature hot air delivered from below the base 101 will pass through the material layer evenly upwards through the micropores 107. The initial moisture content of the material near the feed inlet 113 is higher. The number of openings at the corresponding position can slow down the upward flow rate of the hot air and avoid the high moisture content wet material clumps being impacted by the high-speed airflow to produce local agglomeration. The moisture content of the material in the upper part of the chamber gradually decreases. The higher opening rate can improve the hot air flow efficiency in the upper part, keeping the dried material in a mild suspended state and avoiding the formation of low eutectic agglomerates by local material accumulation and compaction throughout the process.

[0029] The base 101, the middle shell 102, and the upper shell 103 are uniformly equipped with an inner wall 108. The inner wall 108 is covered by a constant temperature heat exchange jacket 109. The constant temperature heat exchange jacket 109 has a reserved through flow channel 110. The waste heat medium recovered by the integrated heat pump dehumidification circulation component 400 is introduced into the flow channel 110. The medium can completely surround the inner wall 108 of all shells along the flow channel 110. The continuous circulation of the medium carries away or transfers heat, so that the overall temperature of the inner wall of the drying chamber 105 is kept at a uniform value, eliminating the situation of high temperature in a single local area, and avoiding the melting and sticking of chenodeoxycholic acid wet products when in contact with the high temperature inner wall for a long time. The arrangement of the flow channel 110 completely fitting the outer side of the inner wall 108 can increase the heat exchange contact area between the waste heat medium and the chamber shell, make full use of the low temperature waste heat recovered by the heat pump, reduce the energy consumption of additional heat sources, and rely on the auxiliary heating of the overall jacket to maintain a stable low temperature environment throughout the drying chamber 105, inhibiting the oxidation and polymerization side reactions of heat-sensitive materials from the environmental temperature level.

[0030] The hot air assembly 200 establishes a connection channel with the pipe 201 and the base 101. The constant temperature process hot air prepared by the integrated heat pump dehumidification circulation assembly 400 can be directly sent into the base 101 through the hot air assembly 200 and the pipe 201. The hot air penetrates the gradient airflow distribution plate 106 from the bottom of the cavity and contacts the material. The upward conveying path of the hot air can continuously lift the particles to form a suspended fluidized state. The hot air first contacts the bottom wet material and can quickly remove the free moisture on the surface of the material, destroying the low eutectic system formed by the water-containing material. This reduces the probability of the material becoming sticky and clumping from the beginning of drying. The closed pipeline structure of the pipe 201 can prevent heat loss during the hot air conveying process, ensuring that the temperature of the hot air entering the drying cavity 105 will not fluctuate significantly and is stably maintained in the low temperature drying range of 45 to 60 degrees Celsius.

[0031] The liquid collection component 300 is connected to the dryer body 100 via pipe 2 301. The condensed water vapor carried by the hot and humid airflow inside the drying chamber 105 can flow into the liquid collection component 300 along pipe 2 301. A collection cylinder 303 is set at the bottom of the liquid collection component 300. The liquid water formed by the condensation of water vapor will be collected into the collection cylinder 303 by gravity and stored in a unified manner. This makes it convenient for operators to drain the moisture inside the equipment and prevent the condensed water from flowing back and contacting the material inside the drying chamber 105, causing the material to become damp. The connection position of pipe 2 301 is set in the upper shell 103 area of ​​the dryer body 100, corresponding to the airflow outlet position with the highest humidity inside the chamber. This can promptly exhaust the high humidity airflow out of the chamber, continuously reduce the water vapor concentration inside the drying chamber 105, and accelerate the speed at which the moisture inside the material migrates and evaporates outward.

[0032] The blower assembly 600 is interconnected with the liquid collection assembly 300 via pipe 603. The blower 601 serves as the power source for the entire fluidized air supply structure, continuously providing circulation power for the entire closed-loop hot air circuit. The airflow generated by the blower 601 can continuously transport the hot and humid air inside the drying chamber 105 to the liquid collection assembly 300 and the integrated heat pump dehumidification circulation assembly 400 to complete dehumidification and heat exchange. Pipe 603, as a sealed connecting pipe, ensures that the hot air circulation does not come into contact with the outside air throughout the entire process, maintaining the closed-loop operation mode of the entire system. The blower 601 is equipped with... Chimney 602 is in a closed state during normal drying operation, and the entire system will not emit hot air or dust. Chimney 602 can be briefly opened to balance the air pressure inside and outside the cavity during equipment maintenance or cavity depressurization, taking into account both the closed-loop production and the safety depressurization requirements of the equipment. The blower assembly 600, liquid collection assembly 300, and dryer body 100 are connected in series by a closed pipeline to form a complete circulating air duct, eliminating the need for additional external air ducts between multiple separate equipment, reducing the overall factory space occupied by the equipment, and avoiding the problems of heat loss and dust leakage caused by multiple external air ducts.

[0033] The entire structure relies on the dryer body 100, hot air assembly 200, liquid collection assembly 300, blower assembly 600, integrated heat pump dehumidification circulation assembly 400, and vacuum dehumidification assembly 500 to form the overall layout. All structures involved in hot air circulation, heat exchange, water vapor collection, and negative pressure dehumidification are integrated inside the equipment frame. The medium flow between the components is completed by a closed pipeline, eliminating the need for multiple separate equipment units. The operating conditions of each component can be synchronized and matched. The vacuum dehumidification assembly 500 continuously extracts the rarefied air inside the drying chamber 105 to maintain negative pressure. The heat pump circulation system simultaneously completes heat recovery and water vapor condensation. The blower assembly 600 dynamically adjusts the circulating air volume according to the material state. Multiple functions are completed simultaneously within the same closed drying chamber 105. Relying on the integrated closed space, it simultaneously achieves multiple functions such as negative pressure boiling point reduction low-temperature drying, waste heat circulation energy saving, low air volume gentle microfluidization, and centralized water vapor recovery. It is suitable for the production requirements of batch drying of chenodeoxycholic acid low eutectic heat-sensitive wet products.

[0034] Example 2, see Figure 1-9The vacuum dehumidification assembly 500 is a silent, explosion-proof vacuum unit, connected to the base 101 via pipe 501. A ventilation plate 111 with filter holes 112 is installed at the bottom of the base 101 to allow airflow. A filter bag 104 is installed on the upper housing 103. Pipe 2 301 is connected to pipe 6 603 via pipe 3 302. The integrated heat pump dehumidification circulation assembly 400 includes pipe 401 connected to the intermediate housing 102, a waste heat recovery heat exchanger 406 located near the intermediate housing 102, an evaporator 402 near the other end of pipe 401, a compressor 404 located above the evaporator 402, an expansion valve 403 located on one side of the compressor 404, and a condenser 405 located on the other side of the compressor 404. The waste heat recovery heat exchanger 406 is a duct-jacketed plate heat exchange structure.

[0035] Specifically, the vacuum dehumidification assembly 500 adopts a silent and explosion-proof vacuum unit structure. The vacuum dehumidification assembly 500 forms a through connection structure with the base 101 through the pipe 501, so that the vacuum negative pressure extraction can directly act on the bottom area of ​​the base 101. The bottom of the base 101 is fixedly equipped with a ventilation plate 111. The surface of the ventilation plate 111 is evenly distributed with filter holes 112. The humid air and water vapor inside the drying chamber 105 can pass evenly through the filter holes 112 through the ventilation plate 111, and then enter the vacuum dehumidification assembly 500 through the pipe 501 to complete the continuous extraction operation. Setting the negative pressure extraction point at the bottom of base 101 creates a stable negative pressure gradient from the bottom of the cavity, causing water vapor precipitated inside the material to migrate in an orderly manner from top to bottom. This prevents water vapor from accumulating and stagnating in the upper part of the drying cavity 105, effectively reducing the overall water vapor partial pressure inside the cavity. Combined with a low-temperature hot air environment, this achieves low-pressure, low-temperature vaporization dehydration, allowing the wet chenodeoxycholic acid material to complete moisture removal under conditions far below conventional atmospheric pressure drying temperatures. This avoids the problems of eutectic materials softening, gelatinizing, and melting upon heating. The arrangement of the air exchange plate 111 and filter holes 112 can uniformly rectify the airflow, preventing localized negative pressure concentration from causing strong adsorption and compaction of the bottom material. It maintains the bed material in a loose, micro-fluidized state and prevents large material particles from entering the pipe 501, thus preventing solid particles from entering the vacuum dehumidification component 500 and causing pipe blockage and unit wear. The Vacuum Dehumidification Component 500 features silent and explosion-proof operation. Vibration and noise can be effectively suppressed during long-term continuous operation. The overall operating conditions meet the explosion-proof safety standards for pharmaceutical and fine chemical workshops. It can be adapted to drying production scenarios containing wet materials with trace amounts of organic solvents, avoiding the workshop safety hazards caused by the high operating noise and insufficient explosion-proof level of conventional vacuum equipment, and improving the stability and safety of mass production operation.

[0036] A filter bag 104 is installed and fixed at the upper shell 103. The filter bag 104 is arranged in the airflow outlet area at the top of the drying chamber 105. The fine material powder carried by the circulating airflow in the chamber can be fully intercepted and captured by the filter bag 104. The intercepted powder naturally falls back into the drying chamber 105 under the action of gravity to continue to participate in the drying process. This effectively avoids high-value materials from entering the downstream pipeline with the circulating airflow and causing continuous material loss, and steadily improves the yield of finished product materials. At the same time, it can also purify the circulating airflow, prevent powder from entering the heat pump heat exchange structure and the air supply pipeline and causing dust accumulation and blockage, and reduce the maintenance frequency and cleaning difficulty of the equipment during long-term operation. Pipeline 2 301 forms an interconnected structure with Pipeline 3 302 and Pipeline 6 603, creating a smooth and closed air duct system between the dryer body 100, liquid collection component 300, and blower component 600. This ensures that the entire hot air circulation path is completely closed and continuous, preventing external ambient air from entering the circulation system and maintaining a closed-loop state. This prevents external impurities, moisture, and dust from entering the cavity, ensuring the cleanliness of the drying environment. At the same time, it avoids heat loss and dust pollution from hot air exhaust, keeping the entire drying equipment in a stable low-oxygen, low-humidity, and closed working environment. This continuously inhibits the oxidation and polymerization side reactions of heat-sensitive materials, ensuring the purity and batch stability of the finished product.

[0037] The integrated heat pump dehumidification circulation component 400 is connected to the intermediate shell 102 through pipe 401, so that the heat pump system can be directly connected to the main heat exchange area of ​​the drying chamber 105. The waste heat recovery heat exchanger 406 is arranged near the intermediate shell 102 and adopts a duct jacketed heat exchange structure. The jacketed structure can increase the contact area between the hot air and the heat exchange medium, allowing the circulating hot air entering and leaving the chamber to complete the waste heat exchange, effectively recovering the residual waste heat energy in the circulating airflow. The recovered waste heat can be continuously supplied to the constant temperature heat exchange jacket 109 and the preheating of the incoming air, reducing the dependence of the whole equipment on external heat sources and significantly reducing the heat energy consumption during the continuous operation of the equipment. Evaporator 402 is located at the end of pipe 401 away from the intermediate shell 102. The hot and humid circulating airflow first flows through evaporator 402, and the low-temperature refrigerant inside evaporator 402 completes the cooling and condensation. The moisture contained in the airflow can be quickly condensed and precipitated and flow into liquid collection component 300, realizing continuous deep dehumidification of circulating air, reducing the moisture content of return hot air, avoiding the problem of moisture returning to the adsorbed material in the later stage of drying, and ensuring the efficiency of low-temperature dehydration throughout the process.

[0038] Compressor 404 is positioned above evaporator 402. An expansion valve 403 is installed on one side of compressor 404, and the other side connects to condenser 405. The entire refrigerant piping system forms a complete closed-loop circulation structure. The expansion valve 403 can precisely adjust the refrigerant flow rate and evaporation pressure to match the dehumidification load and heat exchange requirements of different drying stages, ensuring stable and controllable cooling and dehumidification performance of evaporator 402 and avoiding temperature and humidity imbalances caused by fluctuations in operating conditions. Compressor 404 compresses the low-temperature, low-pressure refrigerant to form a high-temperature, high-pressure refrigerant, which is then delivered to condenser 405. Condenser 405 releases heat to provide constant-temperature supplemental heating to the dehumidified low-temperature dry air, precisely heating the circulating air to the required low-temperature range for the process. The entire heat exchange and dehumidification process is continuously circulated, eliminating the need for traditional electric heating or continuous high-temperature steam heating. This allows for the stable supply of low-temperature process hot air while fully recovering and utilizing waste heat. All components work together in a centralized, integrated layout, enabling dehumidification, heat exchange, heating, and waste heat recovery to operate within the same closed-loop system. The operating conditions of each unit are matched and linked, eliminating problems such as lag in heat exchange, parameter mismatch, and heat waste that can occur with separate equipment. It continuously provides constant temperature, low humidity, and clean circulating hot air to the sealed drying chamber 105, stably meeting the low-temperature drying production needs of low-melting-point, heat-sensitive, and easily degradable materials such as chenodeoxycholic acid.

[0039] Example 3, see Figure 1-9 It also includes a variable frequency adaptive microfluidic air supply system, an intelligent multi-parameter collaborative control system, and a dust removal and loss prevention system; the variable frequency adaptive microfluidic air supply system uses blower 601 as a variable frequency stepless speed regulating air supply fan; the intelligent multi-parameter collaborative control system has two built-in quantitative calculation mathematical models, namely a microfluidic boundary judgment model and a multi-variable air volume dynamic correction model; the dust removal and loss prevention system is composed of filter bags 104 in the upper shell 103, which are used to capture fine materials entrained by the circulating airflow and let them fall back to the drying chamber 105.

[0040] The microfluidization boundary determination model includes the formulas for calculating the minimum fluidization velocity and the optimal microfluidization wind speed. Minimum fluidization rate calculation formula: ; Formula for calculating optimal microfluidization velocity: ; in: Minimum fluidization velocity, in m / s; The average particle size of the dried material is expressed in meters (m). True density of the material, in kg / m³ 3 ; Density of closed-loop hot air, unit: kg / m³ 3 ; The acceleration due to gravity is taken as 9.81 m / s².2 ; The dynamic viscosity of the circulating hot air is expressed in Pa·s. The particle Reynolds number; The real-time optimal microfluidic velocity for the equipment is expressed in m / s. This is the vacuum low humidity correction factor, with a value range of 0.90-0.95; The terminal velocity of material particles, in m / s; During equipment operation, the real-time air supply velocity is constrained to and The low-disturbance microfluidization zone between these zones prevents material agglomeration and fine powder dust loss.

[0041] The formula for the multivariable air volume dynamic correction model is: ; in: The real-time output air volume of the blower (601), in m³. 3 / h; The reference microfluidization air volume under steady-state dry material conditions, in m³. 3 / h; This is the correction factor for the moisture content of the material; This is a correction factor for the thickness of the material layer inside the drying chamber; This is the correction factor for the relative humidity inside the drying chamber; The intelligent multi-parameter collaborative control system adaptively matches three sets of correction coefficient value ranges according to different drying stages: Pre-drying high humidity stage, Take 1.10-1.20, Take a concentration of 1.05-1.10; during the intermediate constant temperature drying stage, , , All are approaching 1.0; the low-temperature phase is nearing its end. , Take 0.80-0.90.

[0042] The integrated heat pump dehumidification circulation component 400 forms a closed circulation duct with no hot air exhaust; The hot and humid airflow discharged from the drying chamber 105 first flows through the evaporator 402 to condense and precipitate moisture to complete dehumidification. After dehumidification, the low-temperature airflow passes through the compressor 404 and the condenser 405 to exchange heat and be heated to a low-temperature process hot air of 45-60℃. After passing through the waste heat recovery heat exchanger 406, it is sent into the base 101 and enters the drying chamber 105 for circulation. The vacuum dehumidification component 500 and the integrated heat pump dehumidification circulation component 400 form a dual dehumidification coupling structure of vacuum negative pressure dehumidification and heat pump condensation dehumidification. The flow channel 110 of the constant temperature heat exchange jacket 109 is used to introduce the heat pump to recover waste heat and provide uniform auxiliary heating to the entire drying chamber 105, with a temperature control accuracy of ±0.5℃.

[0043] Specifically, the entire set of equipment is equipped with a variable frequency adaptive microfluidic air supply system, an intelligent multi-parameter collaborative control system, and a dust removal and loss prevention system. These three systems, together with the rest of the machine, form a complete structure that works in conjunction with each other. The variable frequency adaptive microfluidic air supply system uses blower 601 as the power output component. Blower 601 is equipped with a variable frequency stepless speed regulation structure, which can freely change its output airflow speed and gas flow rate. It no longer maintains a fixed single air volume to continuously deliver hot air. It can synchronously adjust the air supply intensity according to the changes in the material state inside the drying chamber 105, thus avoiding various production problems caused by the constant large air volume operation of traditional drying equipment from the perspective of airflow supply. The dust removal and loss prevention system is built upon the filter bag 104 installed inside the upper shell 103. After heat exchange is completed inside the drying chamber 105, the circulating airflow flows upward. Fine material particles carried by the airflow are intercepted and retained on the surface of the filter material after contacting the filter bag 104. After accumulating to a certain weight, the powder falls back into the drying chamber 105 under its own gravity to continue the dehydration process. High-value pharmaceutical raw materials will not be permanently lost by following the airflow into the downstream pipeline. The overall output ratio of materials can be maintained at a stable value for a long time. At the same time, the powder will not continuously accumulate on the surface of heat exchange components such as the evaporator 402 and condenser 405. The heat exchange channels will not be blocked. The cleaning and maintenance interval can be extended during long-term operation of the equipment, and the labor time consumed by manually cleaning the equipment pipelines and heat exchange components can be reduced accordingly.

[0044] The intelligent multi-parameter collaborative control system incorporates two sets of mathematical models capable of real-time numerical calculations. These models are responsible for fluidization interval determination and real-time airflow correction, respectively. The microfluidization boundary determination model relies on the minimum fluidization velocity calculation formula and the optimal microfluidization airflow velocity calculation formula to complete numerical calculations. These formulas incorporate multiple physical parameters related to the material and hot air conditions, including the average particle size of the dried material, the true density of the material, the density of the closed-loop hot air, the dynamic viscosity of the circulating hot air, and the particle Reynolds number. Gravitational acceleration is calculated using a fixed standard value, and a vacuum low-humidity correction coefficient is applied. The equipment operates in a closed negative pressure environment, limiting the stable value range. During operation, the equipment continuously calculates the numerical range corresponding to the minimum fluidization velocity and the final velocity of material particles. The airflow velocity output by blower 601 is continuously limited to the operating range between the two sets of critical values. Within this range, the disturbance intensity of the airflow on the material is maintained at a low level. The material at the bottom layer will not be compacted due to excessively low airflow velocity, nor will a large amount of fine powder be carried away from the material layer due to excessively high airflow velocity. From the perspective of fluidization state judgment criteria, the loose and mild material suspension state is stably maintained, reducing the occurrence of clumping and adhesion of wet chenodeoxycholic acid and the loss of fine powder.

[0045] The multivariate dynamic airflow correction model uses the real-time output airflow of blower 601 as the final calculation result, and the baseline microfluidized airflow under steady-state dry material conditions as the basic calculation value. The material moisture content correction coefficient, the material layer thickness correction coefficient within the drying chamber, and the relative humidity correction coefficient within the drying chamber are simultaneously involved in the numerical correction calculation. The intelligent multi-parameter collaborative control system adjusts the value ranges of the three sets of correction coefficients according to different stages of the drying operation. When the equipment operates in the pre-drying high-humidity stage, the material moisture content correction coefficient and the relative humidity correction coefficient within the drying chamber are set to larger values, resulting in a slight increase in the output airflow of blower 601. The stronger airflow disturbance can break up the high-moisture clumps of wet material that have just been put into the equipment, quickly peel off the free moisture adhering to the material surface, and destroy the eutectic system formed by the mixture of wet material and water, thus avoiding problems in the initial drying stage. When the material comes into contact with the inner wall of the constant temperature heat exchange jacket 109, it melts and sticks to the wall. During the middle stage of constant temperature drying, the three correction coefficients are close to the unit value, and the output air volume of blower 601 is maintained in a stable standard range. The hot air and the granular material can maintain a stable and sufficient contact heat exchange state. During the low temperature final stage, the correction coefficients for material moisture content and relative humidity inside the drying chamber are lowered to a smaller value, and the output air volume of blower 601 is reduced accordingly to reduce the airflow's ability to carry fine powder. Combined with the vacuum negative pressure environment, residual trace moisture is removed. The entire air volume adjustment process is automatically completed based on numerical calculation. There is no need for operators to observe the material status on-site and manually change the blower operating parameters. There will be no fluctuations in the air supply conditions between different production batches caused by human factors. The drying process has a unified and repeatable execution standard.

[0046] The integrated heat pump dehumidification circulation component 400 forms a closed-loop circulation duct with no hot air emission throughout the entire process. The entire hot air delivery path is within a sealed pipeline, preventing ambient air from entering the circulation system. After heat exchange is completed inside the drying chamber 105, the humid and hot air carrying a large amount of water vapor will preferentially flow through the evaporator 402. Heat exchange occurs between the low-temperature refrigerant and the humid and hot air, and the moisture contained in the air condenses and precipitates upon cooling, significantly reducing the water vapor content inside the air. The low-temperature airflow after dehumidification continues to flow to the compressor 404 and condenser 405. The low-temperature, low-pressure refrigerant is compressed by the compressor 404 and transformed into a high-temperature, high-pressure state. The high-temperature refrigerant releases heat inside the condenser 405. The dehumidified low-temperature airflow is heated to a stable temperature range of 45 to 60 degrees Celsius. The heated airflow then passes through the waste heat recovery heat exchanger 406 to exchange heat again, fully recovering the residual heat inside the airflow. The low-temperature process hot air, having completed the entire heat exchange process, is sent into the base 101, passes through the ventilation plate 111 and the gradient airflow distribution plate 106, and re-enters the drying chamber 105 to participate in the material dehydration process. The entire hot air circulation process runs continuously without releasing heat or dust. During equipment operation, the heat energy can be continuously recycled and reused, eliminating the need to continuously consume a large amount of fresh high-temperature heat source. The heat energy consumption during the entire equipment operation phase can be significantly reduced.

[0047] The vacuum dehumidification component 500 and the integrated heat pump dehumidification circulation component 400 work together to form a dual dehumidification coupling structure. The vacuum dehumidification component 500 continuously extracts the rarefied air inside the drying chamber 105 to reduce the internal air pressure. The vaporization temperature of water decreases synchronously with the decrease in air pressure. The integrated heat pump dehumidification circulation component 400 relies on the evaporator 402 to continuously condense the water vapor inside the airflow. The simultaneous action of the two dehumidification methods can continuously reduce the partial pressure of water vapor inside the drying chamber 105, accelerate the migration and evaporation of moisture inside the material, shorten the overall heating time of the material, and reduce the probability of thermally sensitive side reactions. The waste heat medium recovered by the integrated heat pump dehumidification circulation component 400 is introduced into the flow channel 110 inside the constant temperature heat exchange jacket 109. The waste heat medium can completely surround the entire inner wall 108 of the drying chamber 105 to complete heat exchange. The overall temperature control accuracy of the equipment is maintained within the range of ±0.5 degrees Celsius. There are no areas with excessively high local temperatures inside the drying chamber 105. The wet chenodeoxycholic acid material will not melt or gelatinize due to prolonged contact with the high-temperature inner wall. The polymerization and oxidation reactions at the molecular level of the material can be continuously inhibited. The content of related substances and color status of different batches of finished products can maintain a uniform standard, reducing the material and time losses caused by product rework and scrap.

[0048] The following is combined Figures 1-9 Explain its working process: The dryer body 100 is vertically constructed by sealing and splicing three sections: base 101, intermediate shell 102, and upper shell 103. The base 101, intermediate shell 102, and upper shell 103 together form a closed drying chamber 105. A gradient airflow distribution plate 106 is horizontally mounted inside the drying chamber 105. A large number of micropores 107 are evenly opened on the surface of the gradient airflow distribution plate 106. The opening rate of the micropores 107 increases gradually from bottom to top along the material feed end to ensure uniform micro-fluidization of the material under low air volume and no dead zone in the bed.

[0049] The inner side of the intermediate shell 102 is an inner wall 108, and the outer side of the inner wall 108 is completely covered by a constant temperature heat exchange jacket 109. The constant temperature heat exchange jacket 109 has a continuous surrounding flow channel 110. The flow channel 110 is filled with the waste heat medium recovered by the integrated heat pump dehumidification circulation component 400, which provides uniform auxiliary heating to the entire drying chamber 105. The temperature control accuracy can reach ±0.5℃, eliminating local high temperature dead corners and preventing the wet product of deoxycholic acid from melting and sticking to the wall.

[0050] The hot air assembly 200 is connected to the side of the base 101 via pipe 201, and is used to deliver constant-temperature process hot air to the bottom of the drying chamber 105. A ventilation plate 111 is fixedly installed at the bottom of the base 101. The ventilation plate 111 is filled with filter holes 112, allowing airflow to pass evenly upwards through the filter holes 112 and through the gradient airflow distribution plate 106 into the drying chamber 105. The vacuum dehumidification assembly 500 is a silent, explosion-proof vacuum unit. The vacuum dehumidification assembly 500 is connected to the base 101 via pipe 501, continuously extracting moisture from the drying chamber 105 to stably maintain a negative pressure low-oxygen environment of -0.07 to -0.09 MPa, inhibiting the oxidation and polymerization of materials to generate impurities.

[0051] A filter bag 104 is suspended inside the upper housing 103. The filter bag 104 constitutes the core component of the dust removal and loss prevention system. It can capture the fine powder of deoxycholic acid carried by the circulating airflow. The captured powder automatically falls back into the drying chamber 105, reducing the loss of high-value materials. The liquid collection component 300 is connected to the upper housing 103 of the dryer body 100 through pipe 2 301. The bottom of the liquid collection component 300 is detachably equipped with a collection cylinder 303 for collecting liquid water condensed from the heat pump system. The end of pipe 2 301 is connected to pipe 6 603 through pipe 3 302. Pipe 6 603 is connected to the blower component 600.

[0052] The blower assembly 600 serves as the power unit of the variable frequency adaptive microfluidic air supply system. Its core is the blower 601, which is equipped with a variable frequency stepless speed regulating motor. The blower 601 is equipped with a chimney 602 on the outside. Under the closed-loop operation of the equipment, the chimney 602 is sealed and no hot air is discharged, which completely eliminates the leakage of heat and dust.

[0053] The integrated heat pump dehumidification circulation assembly 400 is the closed-loop heat source dehumidification unit of this equipment, which includes pipe 401, waste heat recovery heat exchanger 406, evaporator 402, expansion valve 403, compressor 404, and condenser 405. One end of pipe 401 is connected to the constant temperature heat exchange jacket 109 flow channel 110 of the intermediate shell 102, and the other end of pipe 401 is connected in series with waste heat recovery heat exchanger 406 and evaporator 402. Compressor 404 is arranged above evaporator 402. An expansion valve 403 is installed on one side of the compressor 404 as a throttling device, and the other side of the compressor 404 is connected to condenser 405. The whole set of components forms a closed-loop refrigerant circulation loop.

[0054] The hot and humid airflow discharged from the drying chamber 105 is first introduced into the evaporator 402. The hot and humid air exchanges heat with the low-temperature refrigerant in the evaporator 402, and the water vapor condenses and precipitates to complete deep dehumidification. The dehumidified low-temperature clean airflow enters the condenser 405, absorbs the heat released by the compressor 404 when compressing the refrigerant, and is heated to a low-temperature process hot air of 45-60℃. The heated hot air flows through the waste heat recovery heat exchanger 406 to complete the waste heat pre-exchange, and then is sent to the base 101 through the hot air assembly 200 and the pipe 201. It then passes through the ventilation plate 111 and the gradual airflow distribution plate 106 and re-enters the drying chamber 105 to participate in fluidized drying. There is no hot air exhaust throughout the process, and the waste heat is 100% recovered and reused in a closed loop.

[0055] The vacuum dehumidification component 500 continuously extracts the thin water vapor from the cavity, forming a dual dehumidification coupling mechanism with the heat pump evaporator 402 for condensation and dehumidification. This significantly reduces the partial pressure of water vapor inside the drying cavity 105, achieving rapid dehydration at low temperatures and avoiding the low eutectic softening temperature of wet chenodeoxycholic acid.

[0056] The intelligent multi-parameter collaborative control system has two built-in quantitative mathematical models that can be closed-loop calculated and reproduced: a microfluidization boundary determination model and a multivariate air volume dynamic correction model. All parameters of the two models are solidified and written into the equipment PLC program. The system collects three types of parameters in real time: material moisture content, material layer thickness, and relative humidity of the drying chamber 105. It automatically calculates and adjusts the output air volume and speed of the blower 601, maintaining a microfluidization steady state with low disturbance, no agglomeration, and no fine powder separation throughout the process.

[0057] The model includes formulas for calculating minimum fluidization velocity and optimal microfluidization velocity. The operating airflow of the equipment is forcibly constrained within the safe microfluidization range to prevent agglomeration due to insufficient airflow and dust loss due to excessive airflow. Minimum fluidization rate calculation formula:

[0058] Formula for calculating optimal microfluidization velocity:

[0059] in: Minimum fluidization velocity, in m / s; The average particle size of the dried material is expressed in meters (m). True density of the material, in kg / m³ 3 ; Density of closed-loop hot air, unit: kg / m³ 3 ; The acceleration due to gravity is taken as 9.81 m / s². 2 ; The dynamic viscosity of the circulating hot air is expressed in Pa·s. The particle Reynolds number; The real-time optimal microfluidic velocity for the equipment is expressed in m / s. This is the vacuum low humidity correction factor, with a value range of 0.90-0.95; The terminal velocity of material particles, in m / s; Equipment operation logic: Real-time system calculation and Boundary values ​​are used to strictly control the output air velocity of blower 601 within a certain range. The weak suspension microfluidization zone between them is different from the traditional high turbulence boiling condition, and it can physically prevent wet material from compacting and clumping, and fine powder from being carried away and lost.

[0060] Based on the dynamic changes in material state throughout the drying process, a three-dimensional parameter-coupled airflow correction formula is constructed to correct the output airflow of blower 601 in real time.

[0061] in: The real-time output air volume of the blower (601), in m³. 3 / h; The reference microfluidization air volume under steady-state dry material conditions, in m³. 3 / h; This is the correction factor for the moisture content of the material; This is a correction factor for the thickness of the material layer inside the drying chamber; This is the correction factor for the relative humidity inside the drying chamber; The system automatically matches the values ​​of each correction factor based on the three-stage drying process: ① Low-temperature pre-drying and high-humidity stage: Take 1.10-1.20, Take 1.05-1.10, slightly increase the air volume to break up wet material clumps, disrupt the eutectic system, and prevent initial wall-sticking and melting; ② Constant temperature main drying stage: , , All values ​​approach 1.0, maintaining stable and uniform microfluidization to ensure sufficient heat and mass transfer between hot air and particles; ③ Low-temperature final drying stage: , When the temperature drops to 0.80~0.90, the fan volume is automatically reduced, and combined with vacuum negative pressure static drying, the loss of fine powder dust is completely suppressed.

[0062] Through this quantitative control model, the air volume of the equipment during the entire operation is only 50% to 60% of that of traditional boiling dryers, and the energy consumption of the blower is reduced by more than 30%. At the same time, it takes into account both drying efficiency and product purity, and effectively controls the increase in chenodeoxycholic acid oxidation and polymerization impurities.

[0063] The complete drying process of the whole machine is operated as follows: S1. Feeding stage: The wet granules of deoxycholic acid are fed into the drying chamber 105 through the feed inlet 113. The equipment is closed to form a fully enclosed negative pressure environment. The vacuum dehumidification component 500 is started and the vacuum degree of the chamber is stabilized to -0.07 to -0.09 MPa. S2, Low-temperature pre-drying stage: The integrated heat pump dehumidification circulation component starts at 400°C, and the hot air temperature stabilizes at 45-50°C; the intelligent multi-parameter collaborative control system reads the high moisture content signal and matches the high value. , The coefficient of the blower 601 slightly increases the air volume, breaking up wet material clumps and removing surface free water; S3, Constant Temperature Main Drying Stage: Hot air temperature is maintained at 50-60℃, all correction coefficients approach 1.0, the equipment operates stably with the optimal microfluidic air velocity, and the heat pump and vacuum unit perform simultaneous dual dehumidification to quickly remove the bound water inside the material and shorten the heating time of heat-sensitive materials. S4. Low-temperature finishing stage: The hot air temperature drops to 45℃, and the system automatically adjusts the temperature downwards. , The coefficient reduces the fan air volume, and vacuum drying removes trace amounts of residual moisture; the filter bag 104 recovers fine powder throughout the process, and the condensed water is collected in the collection cylinder 303 for unified discharge. S5. Discharge stage: After drying is completed, release the negative pressure in the chamber, stop the heat pump, vacuum, and blower systems, and take out the dried high-purity chenodeoxycholic acid product.

[0064] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0065] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. An integrated heat pump type low-temperature circulating dryer, comprising a dryer body (100), a hot air assembly (200), a liquid collection assembly (300), and a blower assembly (600), characterized in that: It also includes an integrated heat pump circulation system and a vacuum dehumidification system; The integrated heat pump circulation system includes an integrated heat pump dehumidification circulation component (400), and the vacuum dehumidification system includes a vacuum dehumidification component (500). The dryer body (100) is composed of a base (101), an intermediate shell (102), and an upper shell (103) in sequence. A drying chamber (105) is provided inside the base (101), the intermediate shell (102), and the upper shell (103). A gradual airflow distribution plate (106) is provided inside the drying chamber (105), and micropores (107) are provided on the gradual airflow distribution plate (106). The base (101), the intermediate shell (102), and the upper shell (103) are provided with an inner wall (108), and a constant temperature heat exchange jacket (109) is provided outside the inner wall (108), and the constant temperature heat exchange jacket (109) is provided with a flow channel (110).

2. The integrated heat pump type low-temperature circulating dryer according to claim 1, characterized in that: The hot air assembly (200) is connected to the base (101) via a pipe (201); The liquid collection assembly (300) is connected to the dryer body (100) through pipe two (301), and a collection cylinder (303) is provided at the bottom of the liquid collection assembly (300).

3. The integrated heat pump type low-temperature circulating dryer according to claim 2, characterized in that: The porosity of the micropores (107) increases gradually upward from the feed inlet (113); The blower assembly (600) is connected to the liquid collection assembly (300) via pipe six (603). The blower assembly (600) also includes a blower (601) and a chimney (602) disposed on the blower (601).

4. The integrated heat pump type low-temperature circulating dryer according to claim 3, characterized in that: The vacuum dehumidification assembly (500) is a silent explosion-proof vacuum unit, which is connected to the base (101) through pipe five (501). The bottom of the base (101) is provided with an air exchange plate (111), and the air exchange plate (111) is provided with filter holes (112) to allow airflow to pass through.

5. The integrated heat pump type low-temperature circulating dryer according to claim 4, characterized in that: A filter bag (104) is provided on the upper shell (103), and the second pipe (301) is connected to the sixth pipe (603) through the third pipe (302).

6. The integrated heat pump type low-temperature circulating dryer according to claim 5, characterized in that: The integrated heat pump dehumidification circulation assembly (400) includes a pipe four (401) communicating with the intermediate shell (102), a waste heat recovery heat exchanger (406) disposed near the intermediate shell (102), an evaporator (402) near the other end of the pipe four (401), a compressor (404) disposed above the evaporator (402), an expansion valve (403) disposed on one side of the compressor (404), and a condenser (405) disposed on the other side of the compressor (404). The waste heat recovery heat exchanger (406) is a duct sandwich plate heat exchange structure.

7. The integrated heat pump type low-temperature circulating dryer according to claim 6, characterized in that: It also includes a variable frequency adaptive microfluidic air supply system, an intelligent multi-parameter collaborative control system, and a dust removal and loss prevention system; The variable frequency adaptive microfluidic air supply system uses a blower (601) as a variable frequency stepless speed regulating air supply fan; the intelligent multi-parameter collaborative control system has two sets of quantitative calculation mathematical models built in, namely the microfluidic boundary judgment model and the multivariable air volume dynamic correction model. The dust removal and loss prevention system consists of a filter bag (104) inside the upper shell (103), which is used to capture fine materials carried by the circulating airflow and return them to the drying chamber (105).

8. The integrated heat pump type low-temperature circulating dryer according to claim 7, characterized in that: The microfluidization boundary determination model includes the minimum fluidization velocity calculation formula and the optimal microfluidization wind speed calculation formula. Minimum fluidization rate calculation formula: ； Formula for calculating optimal microfluidization velocity: ； in: Minimum fluidization velocity, in m / s; The average particle size of the dried material is expressed in meters (m). True density of the material, in kg / m³ 3 ; Density of closed-loop hot air, unit: kg / m³ 3 ; The acceleration due to gravity is taken as 9.81 m / s². 2 ; The dynamic viscosity of the circulating hot air is expressed in Pa·s. The particle Reynolds number; The real-time optimal microfluidic velocity for the equipment is expressed in m / s. This is the vacuum low humidity correction factor, with a value range of 0.90-0.95; The terminal velocity of material particles, in m / s; During equipment operation, the real-time air supply velocity is constrained to and The low-disturbance microfluidization zone between these zones prevents material agglomeration and fine powder dust loss.

9. The integrated heat pump type low-temperature circulating dryer according to claim 8, characterized in that: The formula for the multivariable dynamic air volume correction model is: ； in: The real-time output air volume of the blower (601), in m³. 3 / h; The reference microfluidization air volume under steady-state dry material conditions, in m³. 3 / h; This is the correction factor for the moisture content of the material; This is a correction factor for the thickness of the material layer inside the drying chamber; This is the correction factor for the relative humidity inside the drying chamber; The intelligent multi-parameter collaborative control system adaptively matches three sets of correction coefficient value ranges according to different drying stages: Pre-drying high humidity stage, Take 1.10-1.20, Take 1.05-1.10; Mid-term constant temperature drying stage, , , All are close to 1.0; Low-temperature closing stage, , Take 0.80-0.

90.

10. The integrated heat pump type low-temperature circulating dryer according to claim 9, characterized in that: The integrated heat pump dehumidification circulation component (400) forms a closed circulation duct with no hot air exhaust; The hot and humid airflow discharged from the drying chamber (105) first flows through the evaporator (402) to condense and precipitate moisture to complete dehumidification. After dehumidification, the low-temperature airflow passes through the compressor (404) and condenser (405) to exchange heat and be heated to a low-temperature process hot air of 45-60℃. After passing through the waste heat recovery heat exchanger (406) to exchange heat, it is sent into the base (101) and enters the drying chamber (105) for circulation. The vacuum dehumidification component (500) and the integrated heat pump dehumidification circulation component (400) form a dual dehumidification coupling structure of vacuum negative pressure dehumidification and heat pump condensation dehumidification. The flow channel (110) of the constant temperature heat exchange jacket (109) is connected to the heat pump to recover waste heat and provide uniform auxiliary heating to the entire drying chamber (105), with a temperature control accuracy of ±0.5℃.

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