Device for efficiently removing plasticizer in astaxanthin grease and processing technology thereof

Abstract

The invention relates to the technical field of astaxanthin grease purification, in particular to a device for efficiently removing plasticizer content in astaxanthin grease and a processing technology thereof.The device comprises a vertical concentration tank, a jacket heating layer is arranged on the outer wall of the concentration tank, the concentration tank is filled with heat conduction oil, and an electric heating wire is installed in the jacket heating layer; a plurality of microporous gas distributors are annularly and radially embedded in the bottom of the concentration tank; the condensation recovery towers are connected with the top of the concentration tank through pipelines, the refrigeration temperatures in the condensation recovery towers are different, and the temperature in the towers away from the concentration tank is lower. According to the invention, the double-layer microporous gas distributor arranged at the bottom of the concentration tank pumps gas into the tank, and the double-layer microporous gas distributor cooperates with the rotary film scraping mechanism to complete dynamic updating of a gas-liquid interface, so that the removal rate of a plasticizer in grease is increased, and the retention rate of astaxanthin is increased; through the boiling point fractional condensation design of the three-stage gradient condensation recovery tower, directional separation of the plasticizer and the solvent is completed, and the solvent recovery rate and the exhaust gas standard are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of astaxanthin oil purification, and specifically to a device and its processing technology for efficiently removing the content of plasticizers in astaxanthin oil. Background Art

[0002] As a strong antioxidant, the oil extract of astaxanthin is widely used in the food and pharmaceutical fields. The astaxanthin extraction process is easily contaminated by plasticizers dissolved from pipelines and heavy metals brought in by raw materials. For example, phthalate substances such as DEHP and DBP are released from PVC pipelines and plastic storage tanks contacted during the production process; for example, heavy metal pollution comes from the absorption of lead and mercury in water by microalgae cultured from raw materials, and the corrosion of equipment, namely the residues of chromium and nickel in stainless steel.

[0003] In the prior art, fat-soluble solvents such as ethyl acetate, ethanol, and acetone are usually used to extract astaxanthin. Traditional purification technologies have significant defects: the molecular distillation method requires high-temperature operation, resulting in thermal degradation and loss of astaxanthin, and has a low removal rate of plasticizers; although the activated carbon adsorption method can remove some impurities, its adsorption capacity is low and it cannot simultaneously remove heavy metals. Therefore, developing an integrated system for low-loss and synergistic removal of multiple pollutants has become an urgent need in the industry. Summary of the Invention

[0004] In order to overcome the defects in the prior art, the purpose of the present invention is to provide a device and its processing technology for efficiently removing the content of plasticizers in astaxanthin oil, so as to solve the problems proposed in the above background art.

[0005] To achieve the above purpose, on the one hand, the present invention provides a device for efficiently removing the content of plasticizers in astaxanthin oil, including a vertical concentration tank, the inner wall of which is provided with a polytetrafluoroethylene coating, the outer wall is provided with a jacket heating layer filled with heat-conducting oil, and an electric heating wire is installed in the jacket heating layer; the bottom of the concentration tank is radially embedded with a number of microporous gas distributors in a circular shape, the microporous gas distributors are composed of double-layer sintered metal filters, and pores with a diameter of 50-100 μm are opened on the top surfaces of the two layers of filters; a pulse pump for pumping nitrogen into a number of microporous gas distributors is installed on one side of the top of the concentration tank;

[0006] A number of condensation recovery towers are connected to the top of the concentration tank through pipelines. The internal refrigeration temperatures of the a number of condensation recovery towers are different, and the temperature in the tower farther away from the concentration tank is lower. An activated carbon adsorption layer is provided inside the outermost condensation recovery tower;

[0007] A heavy metal trap is connected in series to the outlet of the concentration tank and is filled with a mercapto-modified MIL-101(Cr) adsorbent, which is a three-dimensional mesoporous framework with a pore diameter of 2.9×3.4 nm, and the uncoordinated carboxylic acid oxygen atoms provide heavy metal adsorption sites;

[0008] The on-line monitoring system includes an infrared spectrum probe embedded in the middle of the concentration tank and an inductively coupled plasma probe embedded in the heavy metal trap, and is connected to a PLC controller.

[0009] As a further improvement of this technical solution, the nitrogen gas passing rate of the microporous gas distributor and the grease volume ratio are (0.8 - 1.2):1 (L / min·L), and the pulse frequency of the pulse pump is 10 - 20 Hz.

[0010] As a further improvement of this technical solution, the temperature of the condensation recovery tower is divided into primary condensation: ethanol cooling at -5 to 0 °C; secondary condensation: ethylene glycol cooling at -20 to -15 °C.

[0011] As a further improvement of this technical solution, the height-to-diameter ratio of the heavy metal trap is 3:1, and the operating temperature is 40 - 50 °C.

[0012] As a further improvement of this technical solution, a rotating shaft is provided at the center of the bottom of the concentration tank, and a number of sector-shaped scrapers are radially arranged at the top of the rotating shaft. The gap between the edge of the sector-shaped scraper and the tank wall is 0.3 - 0.5 mm, and the outer surface is provided with a PTFE coating.

[0013] On the other hand, the present invention provides a processing technology for efficiently removing the phthalate content in astaxanthin grease. Using the above-mentioned device for efficiently removing the phthalate content in astaxanthin grease, it includes the following steps:

[0014] S1. Heat the phthalate-containing grease in the concentration tank to 40 - 60 °C;

[0015] S2. Start the pulse pump to introduce pulsed nitrogen through a number of microporous distributors, and maintain the vacuum degree at -0.08 to -0.095 MPa;

[0016] S3. The water vapor volatilized from the concentration tank is first captured by the secondary condensation of a number of condensation recovery towers to capture high-boiling phthalates and macromolecular fat-soluble impurities, then capture low-boiling organic solvents and trace phthalates, and finally purified and discharged through activated carbon adsorption of aerosol particles;

[0017] S4. The degassed grease in the concentration tank flows through the heavy metal trap, and the concentration of heavy metal ions is reduced through the specific adsorption of the thiol-modified MIL-101(Cr) adsorbent to achieve phase separation treatment of pollutants;

[0018] S5. At the same time, the infrared spectrum probe penetrates the grease sample through the diamond crystal total reflection probe, collects spectral data every 30 seconds, and when the peak area decline rate at 1725 cm-1 < 0.5% / min, trigger the PLC to adjust the nitrogen gas flow rate of the pulse pump;

[0019] S6. At the same time, the inductively coupled plasma probe detects Pb 2When + > 0.1 ppm or Hg2+ > 0.05 ppm, activate the heating wire of the heavy metal trap to 50 °C, enhance the adsorption kinetics, reduce the vacuum degree of the concentration tank to -0.08 MPa, and extend the residence time.

[0020] As a further improvement of this technical solution, when the infrared spectroscopy probe detects that the peak intensity at 1725 cm-1 decreases by ≥ 95%, stop the air stripping.

[0021] As a further improvement of this technical solution, the regeneration of the heavy metal trap is eluted with a mixed solution of 0.5 M nitric acid and thiourea.

[0022] As a further improvement of this technical solution, the PLC controller executes the fuzzy PID algorithm, and the response time < 5 seconds.

[0023] As a further improvement of this technical solution, the processed oil meets the requirements that the phthalate esters < 0.05 ppm, the lead and mercury contents < 0.1 ppm, and the astaxanthin retention rate > 98%.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] 1. For the device and its processing technology for efficiently removing the plasticizer content in astaxanthin oil, pump gas into the tank through the double-layer microporous gas distributor set at the bottom of the concentration tank, and cooperate with the rotary scraping film mechanism to complete the dynamic update of the gas-liquid interface, improve the removal rate of plasticizer in the oil and increase the astaxanthin retention rate; through the boiling point fractional condensation design of the three-stage gradient condensation recovery tower, complete the directional separation of the plasticizer and the solvent, and improve the solvent recovery rate and the emission gas standard.

[0026] 2. For the device and its processing technology for efficiently removing the plasticizer content in astaxanthin oil, through the specific coordination of the mercapto-modified MIL-101(Cr) adsorbent in the heavy metal trap, complete the targeted capture of heavy metal ions, eliminate the Pb 2 + / Hg2+ residues and increase the adsorption capacity.

[0027] 3. For the device and its processing technology for efficiently removing the plasticizer content in astaxanthin oil, monitor the concentration tank by setting an infrared spectroscopy probe. The infrared light penetrates the oil sample through the diamond crystal total reflection probe, collect spectral data every 30 seconds, and trigger the PLC to adjust the nitrogen gas flow rate; monitor the heavy metal trap by setting an inductively coupled plasma probe, activate the heating wire of the heavy metal trap, enhance the adsorption kinetics, and reduce the vacuum degree of the concentration tank to meet the requirements of reducing the heavy metal content and increasing the astaxanthin retention rate. Description of the Drawings

[0028] The attached drawings described herein are for illustrative purposes only and are not intended to limit the scope of the present invention disclosure in any way. Additionally, the shapes and proportional dimensions of the components in the figures are only schematic, used to assist in understanding the present invention, and do not specifically define the shapes and proportional dimensions of the components of the present invention. Those skilled in the art, under the teachings of the present invention, can select various possible shapes and proportional dimensions according to specific circumstances to implement the present invention.

[0029] Figure 1 is a schematic diagram of the overall structure of the present invention;

[0030] Figure 2 is one of the schematic diagrams of the astaxanthin oil processing technology structure of the present invention;

[0031] Figure 3 is the second schematic diagram of the astaxanthin oil processing technology structure of the present invention;

[0032] The meanings of the various reference numerals in the figure are as follows:

[0033] 100, concentration tank; 200, condensation recovery tower; 300, heavy metal trap. Detailed implementation manners

[0034] Combined with the description of the attached drawings and the specific implementation manners of the present invention, the details of the present invention can be more clearly understood. However, the specific implementation manners of the present invention described herein are only for the purpose of explaining the present invention and cannot be understood in any way as a limitation of the present invention. Under the teachings of the present invention, the concepts of those skilled in the art are based on any possible variations of the present invention, and these should all be regarded as belonging to the scope of the present invention. The terms "installation" and "connection" should be understood in a broad sense, either directly connected or indirectly connected through an intermediate medium.

[0035] The orientation or positional relationships indicated by the terms "central axis", "vertical", "horizontal", "front", "rear", "upper", "lower", "left", "right", "top", "bottom", "inner", "outer", etc. used herein are based on the orientation or positional relationships shown in the attached drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation of the present invention. In addition, in the description of the present invention, the meaning of "a number of" is two or more, unless otherwise specifically defined.

[0036] Please refer to Figures 1 - 3As shown in the figure, the present invention provides a device for efficiently removing the plasticizer content in astaxanthin oil, including a vertical concentration tank 100 with a polytetrafluoroethylene coating on its inner wall. The coating thickness is 0.5 - 1 mm, and the surface roughness Ra ≤ 0.8 μm, thus forming an anti - sticking layer; the outer wall is provided with a jacket heating layer filled with heat - conducting oil, and an electric heating wire is installed in the jacket heating layer; the concentration tank 100 is made of 316L stainless steel with a wall thickness of 8 - 12 mm and a design pressure of - 0.1~0.5 Mpa; on one side of the top of the concentration tank 100, a pulse pump is installed to pump nitrogen into several microporous gas distributors; at the bottom of the concentration tank 100, several microporous gas distributors are radially embedded in a ring shape. The microporous gas distributor is composed of a double - layer sintered metal filter element, and pores with a diameter of 50 - 100 μm are opened on the top surfaces of the two layers of filter elements. The pore diameter of the upper layer is 50 - 80 μm, and the pore diameter of the lower layer is 80 - 100 μm; the small holes in the upper layer control the initial size of the bubbles, and the large holes in the lower layer prevent blockage, improving the uniformity of bubble rise compared with a single - layer distributor; nitrogen forms a bubble group of 50 - 100 μm through the double - layer microporous distributor, and the surface turbulence of the solvent is induced through the Marangoni effect, causing the plasticizer to migrate from the oil phase to the gas - liquid interface.

[0037] Further, the ratio of the nitrogen inlet rate of the microporous gas distributor to the oil volume is (0.8 - 1.2):1 (L / min·L), which means 0.8 - 1.2 liters of gas are introduced per liter of oil per minute; the pulse frequency of the pulse pump is 10 - 20 Hz; the aperture of the gas distributor adapted to the concentration tank 100 and the liquid layer height are 1 - 1.5 m to prevent gas short - circuit or flooding. For example, when treating 1000 L of astaxanthin oil, the gas inlet rate:

[0038] Lower limit: 0.8 L / (min·L)×1000 L = 800 L / min;

[0039] Upper limit: 1.2 L / (min·L)×1000 L = 1200 L / min.

[0040] Further, a rotating shaft is provided at the center of the bottom of the concentration tank 100, and several fan - shaped scrapers are radially arranged at the top of the rotating shaft. The gap between the edge of the fan - shaped scraper and the tank wall is 0.3 - 0.5 mm, and the outer surface is provided with a PTFE coating; the rotating scraper continuously removes the film formed on the tank wall, exposing the surface of the fresh solvent. Combining with the low - surface - energy characteristics of the PTFE coating, it prevents the secondary adsorption of the plasticizer, making the surface renewal efficiency higher than that of the traditional static method.

[0041] Specifically, several condensation recovery towers 200 are connected to the top of the concentration tank 100 through pipelines. The internal refrigeration temperatures of the several condensation recovery towers 200 are different, and the temperature inside the tower farther away from the concentration tank 100 is lower. An activated carbon adsorption layer is provided inside the condensation recovery tower 200 closer to the outside.

[0042] The temperature of the condensation recovery tower 200 is divided into primary condensation: ethanol cooling at -5 to 0 °C; secondary condensation: ethylene glycol cooling at -20 to -15 °C. The plasticizer / solvent vapor carried by the gas is fractionally condensed in the primary and secondary condensation towers according to the boiling point difference. High-boiling plasticizers: phthalates - DEHP has a boiling point of 386 °C, DBP has a boiling point of 340 °C. Macromolecular fat-soluble impurities: oxidation products of oils and fats, i.e., aldehyde and ketone compounds, are trapped at low temperature by ethanol in the primary condensation. Low-boiling organic solvents: ethyl acetate has a boiling point of 77 °C, ethanol has a boiling point of 78 °C. Trace plasticizers: plasticizers not condensed in the primary condensation are trapped at low temperature by ethanol in the secondary condensation. Primary high-temperature condensation preferentially removes high-boiling plasticizers to avoid fouling in the low-temperature section; secondary deep cooling traps solvents to prevent them from entering the activated carbon section and causing adsorption saturation. Advantage of phase separation: During the stripping process, the plasticizer is transferred from the liquid oil to the gas phase, while heavy metals always remain in the liquid phase, realizing the separate treatment of pollutants by phase.

[0043] Specifically, the heavy metal trap 300 is connected in series to the outlet of the concentration tank 100 and is filled with a mercapto-modified MIL-101(Cr) adsorbent, which is a three-dimensional mesoporous framework, i.e., the MOF framework, and has a pore size of 2.9×3.4 nm, Cr 3 + nodes: form strong coordination bonds with organic ligands (terephthalic acid), and the thermal stability reaches 350 °C; the uncoordinated carboxylic acid oxygen atoms provide heavy metal adsorption sites; the mercapto-modified MOF material forms strong coordination with Pb through -SH 2 + with a binding energy > 200 kJ / mol, realizing specific capture of heavy metals; the mercapto loading > 2.5 mmol / g, and the adsorption capacity for Pb 2 + reaches 480 mg / g.

[0044] Mercapto modification mechanism:

[0045] Modification method, post-synthesis modification: 2,5-dimercapto terephthalic acid (DMTA) replaces the original terephthalic acid through ligand exchange;

[0046] Sulfur loading: 2.8 - 3.2 mmol / g is verified by XPS sulfur element quantitative analysis;

[0047] Adsorption mechanism, soft acid-soft base theory: -SH (soft base) forms strong covalent bonds with Pb 2 + / Hg2+ (soft acid) with a binding energy > 250 kJ / mol;

[0048] Pore confinement effect: The 3.4 nm pore size selectively intercepts heavy metal ions, and the hydrated ionic radius: Pb 2 + 0.401 nm, Hg2+ 0.419 nm.

[0049] Experimental data

[0050]

[0051] Furthermore, the height-to-diameter ratio of the heavy metal trap 300 is 3:1. From hydrodynamics, when the height-to-diameter ratio > 3, the radial distribution uniformity of the fluid improves, and the effective utilization rate increases; the operating temperature is 40 - 50 °C. When the temperature < 40 °C: the diffusion rate is limited, D ∝ T / μ, and the viscosity of the oil is high; when the temperature > 50 °C: the vibration of the MOF framework intensifies, and the shedding rate of mercapto groups increases. TGA shows that when the temperature > 60 °C, the sulfur loss rate > 5%; the thermal stability of astaxanthin: the retention rate > 99.5% at 50 °C, detected by HPLC, and the degradation rate suddenly increases to 3.2% at 60 °C; the viscosity of the oil: the viscosity drops from 320 mPa·s at 25 °C to 85 mPa·s at 40 °C, and the fluidity increases.

[0052] Specifically, the on-line monitoring system includes an infrared spectroscopy probe embedded in the middle of the concentration tank 100 and an inductively coupled plasma probe embedded in the heavy metal trap 300, and is connected to a PLC controller; the PLC controller executes a fuzzy PID algorithm, and the response time < 5 seconds.

[0053] The detection principle of the infrared spectroscopy probe uses ATR (attenuated total reflection) Fourier transform infrared spectroscopy technology (FTIR-ICP on-line monitoring): infrared light (4000 - 400 cm-1) penetrates the oil sample through the diamond crystal total reflection probe; spectral data is collected every 30 seconds. When the peak area decline rate at 1725 cm-1 < 0.5% / min, the PLC is triggered to adjust the nitrogen gas flow rate.

[0054] The detection principle of the inductively coupled plasma probe uses a microwave plasma to excite a high-frequency electric field of 2.45 GHz to ionize argon so that the electron temperature > 6000 K; heavy metal atoms emit characteristic spectral lines:

[0055] Pb: 220.353 nm (sensitivity 0.1 ppb), Hg: 253.652 nm (sensitivity 0.05 ppb); when Pb 2 + > 0.1 ppm or Hg2+ > 0.05 ppm:

[0056] Activate the heavy metal trap 300 to heat it to 50 °C, improve the adsorption kinetics, reduce the vacuum degree of the concentration tank 100 to -0.08 MPa, and extend the residence time.

[0057] The present invention also provides a processing technology for efficiently removing the plasticizer content in astaxanthin oil, using the device for efficiently removing the plasticizer content in astaxanthin oil described above, including the following steps:

[0058] S1. Heat the plasticizer-containing oil in the concentration tank 100 to 40 - 60 °C;

[0059] S2. Start the pulse pump to introduce pulsed nitrogen through several microporous distributors, and maintain the vacuum degree at -0.08 to -0.095 MPa;

[0060] S3. The water vapor volatilized from the concentration tank 100 is secondarily condensed by several condensation recovery towers 200 to first capture high-boiling plasticizers and macromolecular fat-soluble impurities, then capture low-boiling organic solvents and trace plasticizers, and finally purified and discharged after adsorbing aerosol particles by activated carbon;

[0061] S4. The degassed oil in the concentration tank 100 flows through the heavy metal trap 300, and the concentration of heavy metal ions is reduced through the specific adsorption of the mercapto-modified MIL-101(Cr) adsorbent to achieve phase separation treatment of pollutants; the heavy metal trap 300 is regenerated by eluting with a mixed solution of 0.5 M nitric acid and thiourea;

[0062] S5. At the same time, the infrared spectroscopy probe penetrates the oil sample through the diamond crystal total reflection probe, and collects spectral data every 30 seconds. When the peak area decline rate at 1725 cm-1 < 0.5% / min, trigger the PLC to adjust the nitrogen gas flow rate of the pulse pump; when the infrared spectroscopy probe detects that the peak intensity at 1725 cm-1 drops by ≥ 95%, terminate the air stripping; when the infrared spectroscopy detects a sudden increase in the plasticizer concentration, the PLC immediately raises the primary condensation temperature of the condensation recovery tower 200 to 0 °C to prevent ice blockage, and synchronously increases the output of the secondary condensation cooling capacity;

[0063] S6. At the same time, when the inductively coupled plasma probe detects that Pb 2 + > 0.1 ppm or Hg2+ > 0.05 ppm, activate the heating wire of the heavy metal trap 300 to 50 °C, enhance the adsorption kinetics, reduce the vacuum degree of the concentration tank 100 to -0.08 MPa, and extend the residence time; the treated oil meets the requirements that the phthalate esters < 0.05 ppm, the lead and mercury contents < 0.1 ppm, and the astaxanthin retention rate > 98%.

[0064] During the production line application stage: Add astaxanthin oil containing 15 ppm of DEHP and 2 ppm of Pb 2 + to the concentration tank, and set: temperature 50 °C, vacuum degree -0.09 MPa, nitrogen gas flow rate 1 L / min·L of oil, pulse mode 15 Hz, treatment time 90 minutes;

[0065] After detection: The DEHP residue is 0.03 ppm, the removal rate is 99.8%, and Pb 2 + residue is 0.07 ppm, the astaxanthin retention rate is 99.1%, and the purity of the condensed and recovered plasticizer > 99%.

[0066] In addition, adjust the microporous gas distributor to a single-layer structure, and keep other conditions unchanged. The results are as follows:

[0067] The DEHP removal rate is only 78.5%, and the treatment time is extended to 150 minutes, which proves the key role of the double-layer microporous structure in the bubble uniformity. The experimental data are as follows:

[0068] parameter the present invention traditional distillation method phthalate removal rate 99.8％ 82％ heavy metal residue <0.1 ppm 0.5 ppm energy consumption (kWh / kg) 1.8 4.2 astaxanthin loss ＜2％ 8-12％

[0069] This system has been successfully applied to the astaxanthin production line, and the equipment investment payback period.

[0070] It should be noted that the above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A device for efficiently removing the plasticizer content in astaxanthin oil, characterized in that: The invention comprises a vertical concentrating tank (100), the inner wall of which is provided with a polytetrafluoroethylene coating, the outer wall of which is provided with a jacket heating layer and filled with heat-conducting oil, and an electric heating wire is installed in the jacket heating layer; a plurality of microporous gas distributors are embedded in the bottom of the concentrating tank (100) in an annular radial shape, the microporous gas distributors are composed of a double-layer sintered metal filter element, and the top surfaces of the two layers of filter elements are provided with pores with an aperture of 50-100 μm; a pulse pump for pumping nitrogen into the plurality of microporous gas distributors is installed on one side of the top of the concentrating tank (100); A plurality of condensation recovery towers (200) are connected to the top of the concentration tank (100) through pipelines, the internal refrigeration temperatures of the plurality of condensation recovery towers (200) are different, and the temperature in the tower is lower as it is farther away from the concentration tank (100), and an activated carbon adsorption layer is arranged inside the outer condensation recovery tower (200); A heavy metal collector (300) is connected in series to the discharge port of the concentration tank (100), and contains a mercapto-modified MIL-101 (Cr) adsorbent, which is a three-dimensional mesoporous framework with a pore size of 2.9×3.4 nm, and uncoordinated carboxylic acid oxygen atoms provide heavy metal adsorption sites; The online monitoring system comprises an infrared spectrum probe embedded in the middle of the concentration tank (100) and an inductively coupled plasma probe embedded in the heavy metal collector (300), and is connected to a PLC controller.

2. The device for efficiently removing the plasticizer content in astaxanthin oil according to claim 1, characterized in that: The ratio of nitrogen introduction rate to oil volume of the microporous gas distributor is (0.8-1.2):1 (L / min·L), and the pulse frequency of the pulse pump is 10-20 Hz.

3. The device for efficiently removing the plasticizer content in astaxanthin oil according to claim 2, characterized in that: The temperature of the condensation recovery tower (200) is divided into primary condensation: -5 to 0°C ethanol cooling; secondary condensation: -20 to -15°C ethylene glycol cooling.

4. The device for efficiently removing the plasticizer content in astaxanthin oil according to claim 3, characterized in that: The heavy metal collector (300) has a height-to-diameter ratio of 3:1 and an operating temperature of 40-50°C.

5. The device for efficiently removing the plasticizer content in astaxanthin oil according to claim 4, characterized in that: A rotating shaft is arranged at the bottom center of the concentration tank (100), and a plurality of fan-shaped scrapers are radially arranged on the top of the rotating shaft. The gap between the edge of the fan-shaped scraper and the tank wall is 0.3-0.5 mm, and the outer surface is provided with a PTFE coating.

6. A process for efficiently removing the plasticizer content in astaxanthin oil, using the device for efficiently removing the plasticizer content in astaxanthin oil according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1, heating the oil containing plasticizer in the concentration tank (100) to 40-60°C; S2, start the pulse pump to pass pulse nitrogen through several microporous distributors, and maintain the vacuum degree at -0.08~-0.095MPa; S3, the water vapor volatilized from the concentration tank (100) is subjected to secondary condensation in a plurality of condensation recovery towers (200) to first capture high-boiling point plasticizers and large molecular fat-soluble impurities, then capture low-boiling point organic solvents and trace plasticizers, and finally the aerosol particles are adsorbed by activated carbon and purified and discharged; S4, the degassed grease in the concentration tank (100) flows through the heavy metal collector (300), and the concentration of heavy metal ions is reduced through the specific adsorption of the mercapto-modified MIL-101 (Cr) adsorbent, thereby achieving phase separation treatment of pollutants; S5. At the same time, the infrared spectrum probe penetrates the oil sample through the diamond crystal total reflection probe, and collects spectrum data every 30 seconds. When the decrease rate of the 1725cm-1 peak area is less than 0.5% / min, the PLC is triggered to adjust the nitrogen flow rate of the pulse pump; S6, at the same time, the inductively coupled plasma probe detected Pb 2 When Hg2+>0.1ppm or Hg2+>0.05ppm, the heating wire of the heavy metal collector (300) is activated to 50°C, the adsorption kinetics is improved, the vacuum degree of the concentration tank (100) is reduced to -0.08MPa, and the residence time is extended.

7. The process for efficiently removing the plasticizer content in astaxanthin oil according to claim 6, characterized in that: When the infrared spectrum probe detects that the peak intensity of 1725cm-1 decreases by ≥95%, the gas stripping is terminated.

8. The process for efficiently removing the plasticizer content in astaxanthin oil according to claim 7, characterized in that: The heavy metal trap (300) is regenerated by eluting with a mixed solution of 0.5M nitric acid and thiourea.

9. The process for efficiently removing the plasticizer content in astaxanthin oil according to claim 8, characterized in that: The PLC controller executes the fuzzy PID algorithm with a response time of <5 seconds.

10. The process for efficiently removing the plasticizer content in astaxanthin oil according to claim 9, characterized in that: After treatment, the oil meets the requirements of phthalates <0.05ppm, lead and mercury content <0.1ppm, and astaxanthin retention rate >98%.

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