Continuous treatment method for traditional Chinese medicine extraction dregs

Abstract

The invention belongs to the field of medicine residue treatment, and particularly relates to a continuous treatment method for extracting medicine residues from traditional Chinese medicine, which comprises the following steps: pre-desolventizing wet medicine residues by using a twin-screw extruder to remove a part of free solvent so as to obtain soluble medicine residues; secondly, feeding the dissolved medicine residues into a vacuum belt dryer, and carrying out three-area gradient drying under the vacuum degree and nitrogen protection to obtain dry medicine residues; then, ethanol in the removal liquid is recovered through a heat pump type solvent recovery tower and two-stage condensation, and ethanol obtained after TSA molecular sieve dehydration is reused for an extraction process; meanwhile, explosion-proof safety management is achieved through multi-parameter interlocking control, and the COD removal rate is high after the wastewater is subjected to UASB + A / O treatment; and carrying out superfine grinding on the dry medicine residue to serve as a dietary fiber additive. The method realizes continuous treatment of the decoction dregs, closed-loop recovery of the solvent and resource utilization, has the advantages of energy conservation, safety and environmental protection, and is suitable for large-scale treatment of the decoction dregs in the traditional Chinese medicine industry.

Description

Technical Field

[0001] The invention relates to the field of medicinal residue processing, in particular to a continuous processing method for medicinal residue extracted from traditional Chinese medicine. Background Art

[0002] During the traditional Chinese medicine extraction and production process, a large amount of wet drug residue containing ethanol and water is produced.

[0003] Traditional treatment methods have numerous limitations. Residual ethanol solvent in medicinal residues is difficult to efficiently recover, resulting in not only a waste of resources but also flammable and explosive safety hazards. Furthermore, the drying process consumes a lot of energy, requires discontinuous processing, and the moisture content of the dried residue fluctuates greatly, impacting subsequent resource utilization. Furthermore, wastewater and exhaust gas generated during the treatment process can easily cause environmental pollution if not effectively treated, failing to meet environmental protection requirements. Furthermore, traditional equipment for extruding and desolventizing medicinal residues is inefficient, and components are prone to wear and clogging, resulting in high maintenance costs and limited processing capacity. Therefore, to address these issues, a continuous treatment method for extracting medicinal residues from traditional Chinese medicine was proposed. Summary of the Invention

[0004] In order to overcome the problems of low solvent recovery efficiency, discontinuous treatment process, poor safety, substandard environmental protection and low resource utilization rate of medicinal residues in the prior art, the present invention proposes a continuous treatment method for medicinal residues extracted from traditional Chinese medicine.

[0005] The technical solution adopted by the present invention to solve the technical problem is: a continuous treatment method for extracting medicinal residues from traditional Chinese medicine, comprising the following steps: S1. Pre-desolventization by spiral extrusion: The wet medicinal residue (containing 60-80% water and 40-70% ethanol) is continuously fed into a twin-screw extruder. The screw diameter reduction structure (gradually changing from Φ200mm to Φ150mm) forms an extrusion pressure of 0.8-1.0MPa. Combined with the forward / reverse thread element combination and zoned temperature control (room temperature in the feeding section, 60°C in the compression section, and 70°C in the melting section), more than 60% of the free solvent is removed to obtain the dissolved medicinal residue (containing ≤35% water) and the ethanol-containing removal liquid.

[0006] S2. Vacuum zone drying: The dissolved medicinal residue enters the vacuum belt dryer and passes through the high temperature zone (70±2℃), medium temperature zone (55±2℃), and low temperature zone (50±2℃) in sequence under a vacuum degree of -0.09MPa. The residence time is controlled at 20-40min by the adjustable belt speed of 0.3-1.2m / min, and the medicinal residue is dried to a moisture content of ≤5%. Nitrogen is introduced throughout the drying process to maintain the residual oxygen content ≤5%.

[0007] S3. Solvent closed-loop recovery: The ethanol-containing removal liquid enters the heat pump solvent recovery tower (tower temperature 63±2℃) after steady flow through the buffer tank, and the solvent is recovered through the first-level condensation (60℃ hot water) and the second-level condensation (circulating water) in sequence. The condensate is dehydrated by TSA temperature-swing adsorption molecular sieve to obtain ethanol with a purity of ≥95% for reuse in the extraction process.

[0008] S4. Safety and environmental control: Explosion-proof control is achieved through an ethanol concentration sensor (triggered at 0.8% LEL), oxygen content monitoring (≤5%), and tower pressure interlock (≤0.12 MPa). The generated wastewater is treated in a UASB anaerobic reactor + A / O aerobic tank, with a COD removal rate of ≥85%.

[0009] S5. Utilization of dry residue: Ultrafine grinding of dry residue to D90≤45μm and use as dietary fiber additive.

[0010] As a preference, the screw elements of the twin-screw extruder in S1 include a large lead conveying element (lead 80 mm), a variable density compression element (lead 60 mm → 30 mm) and a diamond block shear element (shear rate 1500-2000 s -1 ), a 3-5mm anti-clogging drainage hole is opened in the compression section.

[0011] Preferably, the surface of the twin-screw in S1 is welded with a hard alloy wear-resistant layer of HRC ≥ 55, and the bearing group adopts a heavy-duty thrust bearing (withstanding pressure > 1MPa).

[0012] Preferably, the high-temperature zone of the S2 vacuum belt dryer is equipped with a steam coil (pressure 0.3MPa) or an electric heater (power density 8W / cm²), which is equipped with an infrared moisture meter for real-time monitoring (accuracy ±0.5%). When the moisture content of the medicinal residue drops to 30%, the belt speed is automatically adjusted to enter the medium-temperature zone; a hot air auxiliary system with a wind speed of 0.5m / s is added to the medium-temperature zone, and a cooling water circuit (outlet temperature ≤40°C) is provided in the low-temperature zone.

[0013] Preferably, the belt surface of the vacuum belt dryer in S2 is Teflon coating + 304 stainless steel mesh belt (air permeability 30%), the thickness of the material is controlled as follows: high temperature zone ≤ 50mm, medium and low temperature zone ≤ 30mm, and the CV value (coefficient of variation) of the moisture content of the medicinal residue after drying is <5%.

[0014] As a preferred option, the heat pump system of the heat pump solvent recovery tower in S3 recovers the latent heat of the dryer exhaust (40-50°C), and after raising the temperature, it supplements the heat source in the high-temperature zone, achieving an annual energy saving of 30% in steam; the 60°C hot water generated by the first-stage condensation is used to preheat the wet slag before screw extrusion (preheated to 40±2°C) through the heat exchange pipeline, and circulating water is used for the second-stage condensation.

[0015] Preferably, the TSA molecular sieve dehydration in S3 adopts a dynamic adsorption-regeneration cycle: the adsorption stage is at a pressure of 0.3MPa and a temperature of 25°C, and the regeneration stage is purged with 120°C hot air (air volume 500m³ / h), with a regeneration cycle of 8h, to ensure that the ethanol purity is stable at 95-98%.

[0016] Preferably, the explosion-proof control in S4 also includes: the solvent recovery tower is equipped with a double pressure relief device (0.15MPa bursting disc + 0.12MPa spring safety valve), the emergency cooling system response time is less than 2s (cooling water flow ≥10m³ / h), and the tower body static grounding resistance is less than 4Ω.

[0017] Preferably, the air inlet pressure of the nitrogen protection system in S2 is ≥0.4MPa, and oxygen content monitoring points (accuracy ±0.3%) are set at the feed end, middle section of the medium temperature zone and discharge end of the dryer. When the oxygen content at any monitoring point is greater than 5%, the nitrogen injection rate is automatically increased to 25m³ / h.

[0018] The system for realizing the continuous processing of any Chinese herbal medicine extraction residue includes: a twin-screw extruder (including frequency conversion control, zoned temperature control jacket, vacuum dehydration component), a vacuum belt dryer (including three-zone heating, nitrogen pipeline, online moisture meter), a heat pump recovery tower, a two-stage condenser, a TSA dehydration device, a safety control unit (ethanol / oxygen sensor, safety PLC, nitrogen inerting system), a UASB+A / O wastewater treatment unit and ultrafine grinding equipment.

[0019] The present invention is beneficial in that: 1. This invention utilizes a twin-screw extruder with a variable screw diameter (gradually changing from 200mm to 150mm), a combination of forward and reverse screw elements (a large-lead conveying element + a variable-density compression element + a diamond-shaped shearing element), and a zoned temperature control design to achieve continuous and efficient removal of more than 60% of the free solvent in wet medicinal residue. This solves the low efficiency and discontinuity issues of traditional desolventizing methods and improves the efficiency and continuity of solvent pre-removal. 2. This invention utilizes the vacuum belt dryer's three-zone temperature gradient (high temperature zone 70±2°C, medium temperature zone 55±2°C, low temperature zone 50±2°C), adjustable belt speed (0.3-1.2m / min), and nitrogen protection system to achieve precise temperature-controlled drying of medicinal residues from a moisture content of ≤35% to ≤5%. This solves the problems of high energy consumption and large moisture content fluctuations associated with traditional drying, and improves the quality stability of the dried medicinal residues (CV value <5%).

[0020] 3. This invention utilizes a heat pump solvent recovery tower with two-stage condensation (first stage 60°C hot water, second stage circulating water) combined with a closed-loop TSA temperature swing adsorption molecular sieve design to achieve efficient recovery and dehydration of ethanol solvents. This solves the problems of low solvent recovery and insufficient purity, and improves ethanol reuse rate (purity ≥ 95%) and resource utilization.

[0021] 4. The present invention realizes the resource utilization function of the medicinal residue through the process design of ultrafine grinding of dry medicinal residue to D90≤45μm, solves the problem of solid waste disposal of medicinal residue, and improves the economic value of the medicinal residue (as a dietary fiber additive).

[0022] 5. This invention utilizes an ethanol concentration sensor (triggered at 0.8% LEL), oxygen content monitoring (≤5%), a tower pressure interlock (≤0.12 MPa), and a dual pressure relief device to achieve explosion-proof safety control during the treatment process, addressing potential safety hazards during ethanol treatment and improving production safety. The wastewater treatment system, comprising a UASB anaerobic reactor and an A / O aerobic tank, achieves efficient purification of high-COD wastewater, addressing environmental pollution during the treatment process and improving environmental compliance rates. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 is a process flow chart of the present invention; Figure 2 This is a schematic diagram of the structure distribution of the twin-screw extruder of the present invention; Figure 3 This is a schematic diagram of temperature zones of the vacuum belt dryer of the present invention; Figure 4 This is a schematic diagram of the explosion-proof control system for a solvent recovery tower of the present invention. DETAILED DESCRIPTION

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] The following is combined with Figure 1-4To further explain this application, The present application discloses a method for continuously processing the residues of traditional Chinese medicine extraction. Figures 1 to 4 A continuous processing method for extracting Chinese medicine residues comprises the following steps: S1. Pre-desolventization by spiral extrusion: The wet medicinal residue (containing 60-80% water and 40-70% ethanol) is continuously fed into a twin-screw extruder. The screw diameter reduction structure (gradually changing from Φ200mm to Φ150mm) forms an extrusion pressure of 0.8-1.0MPa. Combined with the forward / reverse thread element combination and zoned temperature control (room temperature in the feeding section, 60°C in the compression section, and 70°C in the melting section), more than 60% of the free solvent is removed to obtain the dissolved medicinal residue (containing ≤35% water) and the ethanol-containing removal liquid.

[0027] The twin-screw surface is welded with a hard alloy wear-resistant layer of HRC ≥ 55, and the bearing group adopts heavy-duty thrust bearings (withstand pressure > 1MPa).

[0028] S2. Vacuum zone drying: The dissolved medicinal residue enters the vacuum belt dryer and passes through the high temperature zone (70±2℃), medium temperature zone (55±2℃), and low temperature zone (50±2℃) in sequence under a vacuum degree of -0.09MPa. The residence time is controlled at 20-40min by the adjustable belt speed of 0.3-1.2m / min, and the medicinal residue is dried to a moisture content of ≤5%. Nitrogen is introduced throughout the drying process to maintain the residual oxygen content ≤5%.

[0029] The high-temperature zone of the vacuum belt dryer is equipped with a steam coil (pressure 0.3 MPa) or an electric heater (power density 8 W / cm²), and an infrared moisture meter provides real-time monitoring (accuracy ±0.5%). When the moisture content of the medicinal residue drops to 30%, the belt speed is automatically adjusted to enter the medium-temperature zone. A hot air auxiliary system with a wind speed of 0.5 m / s is added to the medium-temperature zone, and a cooling water circuit is installed in the low-temperature zone (outlet temperature ≤ 40°C). The belt surface of the vacuum belt dryer is a Teflon-coated 304 stainless steel mesh belt (air permeability 30%). The material thickness is controlled to be ≤50 mm in the high-temperature zone and ≤30 mm in the medium-low temperature zone. The CV value (coefficient of variation) of the moisture content of the medicinal residue after drying is less than 5%. The air inlet pressure of the nitrogen protection system is ≥0.4 MPa. Oxygen content monitoring points (accuracy ±0.3%) are set at the dryer feed end, the middle section of the medium-temperature zone, and the discharge end. When the oxygen content at any monitoring point exceeds 5%, the nitrogen injection rate is automatically increased to 25 m³ / h.

[0030] S3. Solvent closed-loop recovery: The ethanol-containing removal liquid enters the heat pump solvent recovery tower (tower temperature 63±2℃) after steady flow through the buffer tank, and the solvent is recovered through the first-level condensation (60℃ hot water) and the second-level condensation (circulating water) in sequence. The condensate is dehydrated by TSA temperature-swing adsorption molecular sieve to obtain ethanol with a purity of ≥95% for reuse in the extraction process.

[0031] The heat pump system of the heat pump solvent recovery tower recovers the latent heat of the dryer exhaust (40-50°C), and after raising the temperature, it supplements the heat source in the high-temperature zone, achieving an annual energy saving of 30% steam. The 60°C hot water generated by the first-stage condensation is used through the heat exchange pipeline to preheat the wet drug residue before screw extrusion (preheated to 40±2°C). The second-stage condensation uses circulating water, and the TSA molecular sieve dehydration adopts a dynamic adsorption-regeneration cycle: the pressure in the adsorption stage is 0.3MPa and the temperature is 25°C. The regeneration stage is purged with 120°C hot air (air volume 500m³ / h). The regeneration cycle is 8h, ensuring that the ethanol purity is stable at 95-98%.

[0032] S4. Safety and environmental control: Explosion-proof control is achieved through an ethanol concentration sensor (triggered at 0.8% LEL), oxygen content monitoring (≤5%), and tower pressure interlock (≤0.12 MPa). The generated wastewater is treated in a UASB anaerobic reactor + A / O aerobic tank, with a COD removal rate of ≥85%.

[0033] Explosion-proof controls also include: the solvent recovery tower is equipped with a dual pressure relief device (0.15MPa bursting disc + 0.12MPa spring safety valve), the emergency cooling system response time is less than 2s (cooling water flow ≥10m³ / h), and the tower body static grounding resistance is less than 4Ω.

[0034] S5. Utilization of dry residue: Ultrafine grinding of dry residue to D90≤45μm and use as dietary fiber additive.

[0035] As a preference, the screw elements of the twin-screw extruder in S1 include a large lead conveying element (lead 80 mm), a variable density compression element (lead 60 mm → 30 mm) and a diamond block shear element (shear rate 1500-2000 s -1 ), a 3-5mm anti-clogging drainage hole is opened in the compression section.

[0036] A system for realizing a continuous treatment method for any Chinese medicine extraction residue, comprising: Pretreatment unit: twin-screw extruder (including variable frequency motor, graded temperature control jacket, vacuum deliquescence component).

[0037] Drying unit: Vacuum belt dryer (including three-zone heating system, nitrogen protection pipeline, online moisture meter).

[0038] Solvent recovery unit: heat pump recovery tower, two-stage condenser, TSA molecular sieve dehydration device.

[0039] Safety control unit: ethanol concentration sensor, oxygen content analyzer, safety PLC (SIL2 level), nitrogen inerting system, pressure relief cooling assembly.

[0040] Environmental protection unit: UASB reactor, A / O aerobic tank.

[0041] Resource recovery unit: ultrafine grinding equipment (inert gas protection).

[0042] Taking Danshen alcohol extract residue (containing 65% ethanol and 20% water) as an example, the specific steps are as follows: Screw extrusion pre-desolventization: set the extrusion pressure to 0.8 MPa, the feeding section to room temperature, the compression section to 60°C, the melting section to 70°C, the drainage hole vacuum degree to -0.06 MPa, remove 58% of the ethanol, and obtain the dissolved drug residue (32% water content).

[0043] Vacuum belt drying: vacuum degree - 0.09MPa, belt speed 0.8m / min, residence time 35min; high temperature zone 70℃, medium temperature zone 55℃, low temperature zone 50℃, nitrogen residual oxygen content 4%, the moisture content of the dried medicinal residue is 4.7%.

[0044] Solvent recovery: The recovery tower temperature is 63°C, the first-stage condensation hot water preheats the wet drug residue to 40°C, and the VOCs emission concentration after the second-stage condensation is 18mg / m³; the ethanol purity after TSA molecular sieve dehydration is 96.5%.

[0045] Safety and environmental protection: The ethanol concentration throughout the process is less than 0.8% LEL, and the oxygen content is 4.2%; the COD value of the wastewater after UASB+A / O treatment is 95mg / L.

[0046] Resource utilization: The dry residue is crushed to D90=42μm, with a salvianolic acid B retention rate of 89.3% (HPLC detection), meeting the standards for dietary fiber additives.

[0047] 1. Process flow chart (including material flow and energy flow) (1) Overall layout: Horizontal flow continuous processing system, from left to right there are four major units: pretreatment, drying, recycling, and resource utilization.

[0048] (2) Material flow (solid arrows): wet drug residue inlet → twin-screw extruder → dissolved drug residue → vacuum belt dryer → dry drug residue → ultrafine grinder → dietary fiber product; extrusion removal liquid → buffer tank → heat pump recovery tower → TSA molecular sieve → 95% ethanol (reuse).

[0049] (3) Energy flow (dashed arrows): dryer exhaust (40-50℃) → heat pump heating → recovery tower heat source; first-stage condensing hot water (60℃) → wet slag preheating (40±2℃).

[0050] (4) Safe and environmentally friendly flow: VOCs recovery tower → secondary condensation → emission standards (<20mg / m³); wastewater → UASB+A / O treatment → COD ≤ 100mg / L.

[0051] 2. Twin-screw extruder structure distribution diagram (1) The diameter-changing structure of the screw from the feed end (left) to the discharge end (right).

[0052] (2) Structural annotation: Feeding section: diameter Φ200mm, large lead conveying element (lead 80mm, blue); Compression section: diameter Φ180mm, variable density compression element (lead 60mm→30mm gradient, orange), 3-5mm drainage hole on the side wall (connected to vacuum pump); Melting section: diameter Φ150mm, diamond-shaped shear element (red, marked shear rate 1500-2000s⁻¹).

[0053] (3) Auxiliary annotation: Wear-resistant layer: Screw surface is surfacing with hard alloy (partial enlarged image, marked HRC≥55); Vacuum interface: the arrow points to the drain hole (marked "-0.06MPa"); Temperature control jacket: zone marking (feeding section: room temperature; compression section: 60°C; melting section: 70°C).

[0054] 3. Temperature Zone Segmentation Diagram of Vacuum Belt Dryer (1) Display the direction of mesh belt movement (left to right) and the layout of three temperature zones.

[0055] (2) Partition marking: High temperature zone: 40% of the length, steam coil / electric heater icon, material thickness ≤50mm, temperature 70±2℃.

[0056] Medium temperature zone: Length accounts for 30%, hot air circulation icon (wind speed 0.5m / s), material thickness ≤30mm, temperature 55±2℃.

[0057] Low temperature zone: Length accounts for 30%, cooling water pipeline icon, outlet temperature ≤40℃, temperature 50±2℃.

[0058] (3) Common components: Mesh belt: Teflon coating + 304 stainless steel (marked air permeability 30%).

[0059] Nitrogen pipe: runs through three zones and connects to three oxygen analyzers (monitoring points P1-P3).

[0060] 4. Schematic diagram of the explosion-proof control system of the solvent recovery tower (1) Layered structure diagram: From top to bottom, it is divided into monitoring layer, tower layer, and emergency layer.

[0061] (2) Core components: Monitoring layer: ethanol concentration sensor (labeled "≥0.8%LEL trigger"), temperature sensor (labeled "70℃ trigger"), pressure sensor (labeled "0.12MPa trigger").

[0062] Tower layer: Heat pump icon (recovering 40-50℃ exhaust from dryer), two-stage condenser (first stage: 60℃ hot water; second stage: circulating water).

[0063] Emergency floor: Nitrogen inerting valve (response time 0.3s, marked "residual oxygen ≤ 5%"), bursting disc (0.15MPa) + safety valve (0.12MPa), emergency cooling water (flow rate ≥ 10m³ / h, with the pipeline arrow pointing to the tower body) (3) Interlocking logic: sensor → SIL2 safety PLC → actuator (nitrogen valve / cooling water valve), electrostatic grounding mark (marked "resistance <4Ω").

[0064] Working Principle: Through the continuous and coordinated operation of five core units: pretreatment - drying - solvent recovery - safety and environmental protection control - resource utilization, the system can achieve efficient recovery of solvents from Chinese herbal medicine residues, reduce the amount of residues, and reuse them as resources. Its core principles include: Continuous desolventizing and drying: Pre-removal of free solvents through twin-screw extrusion, combined with vacuum zone drying to reduce the moisture gradient of the residue and reduce subsequent energy consumption.

[0065] Closed-loop solvent recovery: Utilize heat pump energy-saving technology to recover solvents, combined with temperature swing adsorption dehydration, to achieve ethanol recycling.

[0066] Integration of safety and environmental protection: Explosion-proof control is achieved through multi-parameter monitoring (ethanol concentration, oxygen content, pressure), and a supporting wastewater treatment system ensures discharge meets standards.

[0067] Energy cascade utilization: Recover the latent heat of drying exhaust and waste heat of condensation to reduce overall energy consumption.

[0068] Resource value-added: Dry medicinal residues can be ultra-finely ground and used as dietary fiber additives to realize solid waste resource utilization.

[0069] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and modifications fall within the scope of the invention as claimed.

Claims

1. A continuous processing method for extracting medicinal residues from traditional Chinese medicine, characterized in that: The following steps are involved: S1. Pre-desolventization by spiral extrusion: Wet medicinal residue (60-80% water content, 40-70% ethanol content) is continuously fed into a twin-screw extruder. The screw diameter reduction structure (gradually changing from Φ200mm to Φ150mm) forms an extrusion pressure of 0.8-1.0MPa. Combined with a combination of forward / reverse screw elements and zoned temperature control (room temperature in the feeding section, 60°C in the compression section, and 70°C in the melting section), more than 60% of the free solvent is removed to obtain dissolved medicinal residue (water content ≤35%) and ethanol-containing desolventizing liquid. S2. Vacuum zone drying: The dissolved medicinal residue enters the vacuum belt dryer and passes through the high temperature zone (70±2℃), medium temperature zone (55±2℃), and low temperature zone (50±2℃) in sequence under a vacuum degree of -0.09MPa. The residence time is controlled by the adjustable belt speed of 0.3-1.2m / min for 20-40min, and the dry medicinal residue is dried to a moisture content of ≤5%. Nitrogen is introduced throughout the drying process to maintain the residual oxygen content ≤5%; S3, solvent closed-loop recovery: The ethanol-containing desorbed liquid flows steadily through the buffer tank and enters the heat pump solvent recovery tower (tower temperature 63±2°C). The solvent is recovered through the first condensation (60°C hot water) and the second condensation (circulating water). The condensate is dehydrated by TSA temperature swing adsorption molecular sieve to obtain ethanol with a purity of ≥95% and reused in the extraction process. S4. Safety and environmental control: Explosion-proof control is achieved through an ethanol concentration sensor (triggered at 0.8% LEL), oxygen content monitoring (≤5%), and tower pressure interlock (≤0.12 MPa). The generated wastewater is treated in a UASB anaerobic reactor + A / O aerobic tank, with a COD removal rate of ≥85%; S5. Utilization of dry residue: Ultrafine grinding of dry residue to D90≤45μm and use as dietary fiber additive.

2. The continuous processing method for extracting medicinal residues from traditional Chinese medicine according to claim 1, wherein: The screw elements of the twin-screw extruder in S1 include a large-lead conveying element (lead 80mm), a variable-density compression element (lead 60mm→30mm) and a diamond-shaped shear element (shear rate 1500-2000s⁻¹). The compression section has a 3-5mm anti-clogging drainage hole.

3. The continuous processing method for extracting medicinal residues from traditional Chinese medicine according to claim 1, wherein: The twin-screw surface of S1 is welded with a hard alloy wear-resistant layer of HRC ≥ 55, and the bearing group adopts heavy-duty thrust bearings (withstanding pressure > 1MPa).

4. The continuous processing method for extracting medicinal residues from traditional Chinese medicine according to claim 1, wherein: The high-temperature zone of the S2 medium-vacuum belt dryer is equipped with a steam coil (pressure 0.3MPa) or an electric heater (power density 8W / cm²), and is equipped with an infrared moisture meter for real-time monitoring (accuracy ±0.5%). When the moisture content of the medicinal residue drops to 30%, the belt speed is automatically adjusted to enter the medium-temperature zone. A hot air auxiliary system with a wind speed of 0.5m / s is added to the medium-temperature zone, and a cooling water circuit is installed in the low-temperature zone (outlet temperature ≤40℃).

5. The continuous processing method for extracting medicinal residues from traditional Chinese medicine according to claim 1, wherein: The belt surface of the S2 medium vacuum belt dryer is Teflon coated + 304 stainless steel mesh belt (air permeability 30%), and the material thickness is controlled as follows: ≤50mm in high temperature zone, ≤30mm in medium and low temperature zone, and the CV value (coefficient of variation) of the moisture content of the medicinal residue after drying is <5%.

6. The continuous processing method for extracting medicinal residues from traditional Chinese medicine according to claim 1, wherein: The heat pump system of the heat pump solvent recovery tower in S3 recovers the latent heat of the dryer exhaust (40-50℃), and after raising the temperature, it supplements the heat source in the high-temperature zone, achieving an annual energy saving of 30% in steam; the 60℃ hot water generated by the first-stage condensation is preheated through the heat exchange pipeline to preheat the wet drug residue before spiral extrusion (preheated to 40±2℃), and the second-stage condensation uses circulating water.

7. The continuous processing method for extracting medicinal residues from traditional Chinese medicine according to claim 1, wherein: The TSA molecular sieve dehydration in S3 adopts a dynamic adsorption-regeneration cycle: the adsorption stage is at a pressure of 0.3MPa and a temperature of 25°C, and the regeneration stage is purged with 120°C hot air (air volume 500m³ / h). The regeneration cycle is 8h, ensuring that the ethanol purity is stable at 95-98%.

8. The continuous processing method for extracting medicinal residues from traditional Chinese medicine according to claim 1, wherein: Explosion-proof controls in S4 also include: the solvent recovery tower is equipped with a dual pressure relief device (0.15MPa bursting disc + 0.12MPa spring safety valve), the emergency cooling system response time is less than 2s (cooling water flow ≥10m³ / h), and the tower body static grounding resistance is less than 4Ω.

9. The continuous processing method for extracting medicinal residues from traditional Chinese medicine according to claim 1, wherein: The air inlet pressure of the nitrogen protection system in S2 is ≥0.4MPa. Oxygen content monitoring points (accuracy ±0.3%) are set at the feed end, middle section of the medium temperature zone and discharge end of the dryer. When the oxygen content at any monitoring point is greater than 5%, the nitrogen injection rate is automatically increased to 25m³ / h.

10. A system for implementing the continuous processing method of traditional Chinese medicine extraction residues according to any one of claims 1 to 9, characterized in that: include: Twin-screw extruder (with variable frequency control, zoned temperature control jacket, vacuum dehydration assembly), vacuum belt dryer (with three-zone heating, nitrogen piping, online moisture meter), heat pump recovery tower, two-stage condenser, TSA dehydration device, safety control unit (ethanol / oxygen sensor, safety PLC, nitrogen inerting system), UASB+A / O wastewater treatment unit and ultrafine grinding equipment.

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