Deodorizing method for wool fat by flashing

Abstract

This invention discloses a flash deodorization method for lanolin, belonging to the field of lanolin refining technology. The method includes: S101: dissolving crude lanolin in 4-6 times its volume of anhydrous hot ethanol, then sending it to the upper part of a vacuum flash evaporator and spraying it downwards; S102: introducing hot nitrogen gas at a temperature of 95-105℃ into the lower part of the vacuum flash evaporator, with the nitrogen gas in countercurrent contact with the crude lanolin spray solution; S103: after circulating and spraying the crude lanolin in the vacuum flash evaporator for a certain period, sending it to a first oil-water separator for cooling, separating the ethanol to obtain lanolin. The exhaust gas from the vacuum flash evaporator is sequentially sent to a power wave tower, a condenser, a gas-liquid separator, and a vacuum device; anhydrous ethanol is circulated and sprayed in the power wave tower, with the spray solution temperature at 45-50℃. This patented method can deodorize lanolin to odorless levels and also has the advantages of significantly reducing color and achieving a high yield.

Description

Technical Field

[0001] This invention belongs to the field of lanolin refining technology, and specifically relates to a flash evaporation deodorization method for lanolin. Background Technology

[0002] Lanolin is a mixture of esters, hydrocarbons, and lipids secreted by the sebaceous glands of sheep and adhering to their fur. Lanolin and its modified forms are widely used in the cosmetics, leather, and pharmaceutical industries.

[0003] Crude lanolin is recovered from wool scouring wastewater. While its sources are abundant, it contains a high water content, a dark color, a strong odor, and numerous impurities that affect the quality of lanolin, such as dust, sand, plant matter, inorganic salts from sheep sweat, protein decomposition products from feces, urine, blood, and these oxides, pigments, and decomposition products of low-ester components—free fatty acids and free alcohols. Therefore, crude lanolin cannot be directly used in the cosmetics industry and requires refining. Lanolin is typically refined through deacidification, decolorization, deodorization, and / or chromatography. Deodorization commonly uses steam deodorization or vacuum deodorization.

[0004] For example, patent application number CN202110816593.9 uses vacuum deodorization for deodorization. Similarly, patent publication number CN87100677A also uses vacuum deodorization for deodorization.

[0005] Compared to ordinary oils, lanolin has a more complex composition and is more difficult to deodorize. With current technology, it is difficult to deodorize lanolin to the point of being odorless. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a flash deodorization method for lanolin, utilizing the properties of lanolin being insoluble in low-temperature ethanol but soluble in hot ethanol, the volatility of ethanol itself, and the ease of distillation of ethanol. The technical solution is as follows:

[0007] See Figure 2 This invention provides a flash deodorization method for lanolin, the method comprising:

[0008] S101: Dissolve crude lanolin in 4-6 times its volume of anhydrous hot ethanol, then send it to the upper part of the vacuum flash evaporation equipment and spray it downwards.

[0009] S102: Hot nitrogen gas is introduced into the lower part of the vacuum flash evaporation equipment. The temperature of the hot nitrogen gas is 95-105℃ and it comes into countercurrent contact with the crude lanolin spray liquid, which has several functions: first, to heat the crude lanolin; second, to remove odor substances; and third, to evaporate ethanol (with multiple functions: first, to reduce the amount of ethanol; second, to remove some impurities; third, to facilitate the subsequent recovery of lanolin; and fourth, to reduce the amount of liquid carried over by the lanolin).

[0010] S103: Crude lanolin is circulated and sprayed in a vacuum flash evaporator for a certain period of time (specifically 2-5 hours) and then sent to the first oil-water separator for cooling (specifically, reduced to below 25°C). After separating the ethanol, lanolin is obtained.

[0011] The exhaust gas from the vacuum flash evaporator is sequentially sent to the power wave tower (with the pipeline between it and the vacuum flash evaporator kept as short as possible), condenser, gas-liquid separator, and vacuum equipment. Anhydrous ethanol is circulated and sprayed within the power wave tower, and the temperature of the sprayed liquid is maintained at 45-50℃ (the temperature is controlled by adjusting the spray volume to prevent rapid ethanol evaporation and to prevent lanolin solidification). Specifically, exhaust gas enters from the top of the power wave tower and flows downwards. Liquid is sprayed upwards through power wave nozzles in the upper or middle part of the power wave tower (to reduce liquid carryover). Gas and liquid come into countercurrent contact, and the liquid circulates within the power wave tower. Gas is discharged from the bottom of the power wave tower. Preferably, an overflow weir is installed in the upper part of the power wave tower, overflowing liquid to the inner wall of the power wave tower to prevent grease from solidifying on the inner wall. Part of the liquid at the bottom of the power wave tower is sent to the power wave nozzles inside the tower, and the other part is sent to the overflow weir. The vacuum degree of the vacuum flash evaporator is -60 to -30 kPa. Specifically, the spray volume of the vacuum flash evaporation equipment must ensure that, after deodorization, the crude lanolin contains at least one volume of anhydrous ethanol, and the flow rate of hot nitrogen must be greater than 1.0 m³ / h. 3 / h (for a vacuum flash evaporator with a volume of 100L).

[0012] The heating reactor is connected to the vacuum flash evaporation equipment to form a circulating spray system. The heating reactor is equipped with a stirrer and a first heater, etc. The heating temperature of the heating reactor is 50-60℃. Anhydrous hot ethanol and crude lanolin are added to the heating reactor according to the formula.

[0013] The ethanol separated in the first oil-water separator is decolorized with activated carbon and then distilled before being sent to a heated reaction vessel for reuse. The decolorization conditions are 30-40℃, the amount of activated carbon is 3-6% of the weight of lanolin, and the decolorization time is 30-60 minutes. The applicant found that the ethanol separated in the first oil-water separator is darker in color, while the ethanol recovered from the power wave tower and condenser is lighter in color (basically colorless). To simplify the ethanol distillation process, the ethanol separated in the first oil-water separator is decolorized to reduce the difficulty of distillation.

[0014] The liquid output from the vacuum flash evaporator is first filtered (specifically, by a pipeline filter, which is hot filtration) before being sent to the first oil-water separator.

[0015] After a predetermined time, the spray liquid in the power wave tower is output to the second oil-water separator; in the second oil-water separator, the temperature of the liquid is reduced to below 30°C and the lower grease is separated, and the grease (solidified) is sent to the heated reaction vessel for reuse.

[0016] Furthermore, the condensate (mainly ethanol) separated by the condenser and the liquid phase separated by the gas-liquid separator are sent to the power wave tower (while fresh anhydrous ethanol is replenished periodically or as needed). The ethanol separated by the second oil-water separator is then distilled and sent to the heated reaction vessel for reuse.

[0017] Furthermore, the vacuum flash evaporator is equipped with a demister at the top to reduce the entry of grease into subsequent equipment, and a second heater is provided at the bottom to prevent lanolin from solidifying (e.g., heating to 40-50°C). The bottom of the heater is connected to the heating reactor and the first oil-water separator via pipelines.

[0018] Specifically, the condenser has a condensation temperature of 0-10℃ and can adopt a multi-stage structure. The first stage uses circulating water for condensation, and the second stage can use ice-salt water for condensation.

[0019] Specifically, embodiments of the present invention provide a flash deodorization method for lanolin, the method comprising:

[0020] S101: Dissolve crude lanolin in 4-6 times its volume of anhydrous hot ethanol, then send it to the upper part of the vacuum flash evaporation equipment and spray it downwards. The temperature of the spray liquid is 50-60℃.

[0021] S102: Hot nitrogen gas is introduced into the lower part of the vacuum flash evaporator. The temperature of the hot nitrogen gas is 95-105℃ and it is in countercurrent contact with the crude lanolin spray liquid. The vacuum degree of the vacuum flash evaporator is -60 to -30 kPa.

[0022] S103: Crude lanolin is circulated and sprayed in a vacuum flash evaporator for 2-5 hours and then sent to the first oil-water separator for cooling. After separating the ethanol, lanolin is obtained.

[0023] S104: The ethanol separated by the first oil-water separator is decolorized with activated carbon and then distilled before being sent to the heated reactor for reuse. After a predetermined time, the spray liquid in the power wave tower is output to the second oil-water separator; in the second oil-water separator, the liquid temperature is reduced to below 30°C and the lower grease is separated, and the grease is sent to the heated reactor for reuse. The condensate separated by the condenser and the liquid phase separated by the gas-liquid separator are sent to the power wave tower, and the ethanol separated by the second oil-water separator is distilled before being sent to the heated reactor for reuse.

[0024] The exhaust gas from the vacuum flash evaporator is sequentially sent to the power wave tower, condenser, gas-liquid separator, and vacuum equipment. Anhydrous ethanol is circulated and sprayed within the power wave tower, and the temperature of the sprayed liquid is 45-50℃.

[0025] The beneficial effects of the technical solution provided by the embodiments of the present invention are as follows:

[0026] (1) It can deodorize lanolin to the point of being odorless;

[0027] (2) While deodorizing, it can significantly reduce the color of lanolin; for lanolin with low requirements, it can be used directly without decolorization.

[0028] (3) The power wave tower has three functions: first, to cool down lanolin, facilitating subsequent condensation (small condensation temperature difference); second, to recover lanolin (the recovered lanolin is sent to the heated reactor for reuse), increasing the lanolin yield to over 97% (similar to conventional technology); and third, to separate lanolin, preventing it from condensing on the condenser and pipelines, thus avoiding blockages and poor condensation. The condenser recovers the ethanol distilled from the vacuum flash evaporation equipment and the power wave tower. The gas-liquid separator is used to separate the liquid carried over from the power wave tower and the condensate from the condenser.

[0029] (4) It can significantly reduce the solid content of lanolin, dissolve the solid content and make it easier to filter;

[0030] (5) No ethanol discharge. Compared to lanolin, ethanol is very easy to distill and recycle. The ethanol after simple distillation does not contain the pigments and odors contained in lanolin. Usually only a small amount of ethanol needs to be added, and lanolin usually does not contain ethanol. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the flash deodorization system for lanolin provided in an embodiment of the present invention;

[0032] Figure 2 This is a flowchart of the flash evaporation deodorization method for lanolin provided in an embodiment of the present invention. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings.

[0034] Example 1

[0035] Example 1 discloses a flash evaporation deodorization method for lanolin, the method comprising:

[0036] S101: Dissolve 30 kg of crude lanolin (color 14.7, strong odor, brown in color, volume 32 L) in 5 times its volume of anhydrous hot ethanol, then send it to the upper part of the vacuum flash evaporation equipment and spray it downwards at a spray temperature of 57℃.

[0037] S102: Hot nitrogen gas with a temperature of 98℃ is introduced into the lower part of the vacuum flash evaporation equipment and comes into countercurrent contact with the crude lanolin spray liquid. The flow rate of the hot nitrogen gas is 1.5m³. 3 The vacuum degree of the vacuum flash evaporation equipment is -55 kPa per hour. The exhaust gas from the vacuum flash evaporation equipment is sequentially sent to the power wave tower, condenser, gas-liquid separator, and vacuum equipment; anhydrous ethanol is circulated and sprayed inside the power wave tower, and the temperature of the spray liquid inside is 48°C.

[0038] S103: After circulating and spraying crude lanolin in a vacuum flash evaporator for 4 hours, it is filtered and then sent to the first oil-water separator for cooling. After separating ethanol (approximately 46L), 29.2kg of lanolin is obtained.

[0039] S104: The ethanol separated by the first oil-water separator is decolorized with activated carbon and then distilled before being sent to step S101 for reuse. After a predetermined time, the spray liquid in the power wave tower is output to the second oil-water separator; in the second oil-water separator, the liquid temperature is reduced to 20°C and the lower grease is separated, and the grease is sent to step S101 for reuse. The condensate separated by the condenser is sent to the power wave tower, and the ethanol separated by the second oil-water separator is distilled before being sent to step S101 for reuse.

[0040] The treated lanolin has a color index of 8.8, a pale yellow color, no odor, and a melting point of 39.2℃.

[0041] Example 2

[0042] Example 2 discloses a flash evaporation deodorization method for lanolin, the method comprising:

[0043] S101: Dissolve 30 kg of crude lanolin (color 14.7, strong odor, brown in color) in 5.5 times its volume of anhydrous hot ethanol, then send it to the upper part of the vacuum flash evaporation equipment and spray it downwards at a spray temperature of 55℃.

[0044] S102: Hot nitrogen gas with a temperature of 100℃ is introduced into the lower part of the vacuum flash evaporation equipment and comes into countercurrent contact with the crude lanolin spray liquid. The flow rate of the hot nitrogen gas is 1.4 m³ / h. 3 The vacuum degree of the vacuum flash evaporator is -45 kPa. The exhaust gas from the vacuum flash evaporator is sequentially sent to the power wave tower, condenser, gas-liquid separator and vacuum equipment; anhydrous ethanol is circulated and sprayed in the power wave tower and the temperature of the spray liquid inside is 48°C.

[0045] S103: After circulating and spraying the crude lanolin in a vacuum flash evaporator for 4.5 hours, it is filtered and then sent to the first oil-water separator for cooling. After separating the ethanol (approximately 51L), 29.0kg of lanolin is obtained.

[0046] S104: The ethanol separated by the first oil-water separator is decolorized with activated carbon and then distilled before being sent to step S101 for reuse. After a predetermined time, the spray liquid in the power wave tower is output to the second oil-water separator; in the second oil-water separator, the liquid temperature is reduced to 20°C and the lower grease is separated, and the grease is sent to step S101 for reuse. The condensate separated by the condenser is sent to the power wave tower, and the ethanol separated by the second oil-water separator is distilled before being sent to step S101 for reuse.

[0047] The treated lanolin has a color score of 8.9, a pale yellow color, no odor, and a melting point of 39.2℃.

[0048] Verification Example

[0049] The conditions for vacuum deodorization are: vacuum deodorization for 4 hours at a vacuum degree of -65 kPa and a temperature of 90°C.

[0050] The conditions for steam deodorization are: 97℃ and a steam consumption of 0.2 m³ / h. 3 Deodorization was carried out for 4 hours at a concentration of / kg crude lanolin.

[0051] The conditions for nitrogen deodorization are as follows: the crude lanolin is heated to 57°C and sent to a vacuum flash evaporation device, where it is countercurrently contacted with hot nitrogen gas at 98°C, and the vacuum degree is -45 kPa.

[0052] The conditions for ethanol extraction were as follows: lanolin was dissolved in 5 times its volume of hot anhydrous ethanol, the extraction temperature was 57°C, the mixture was stirred for 2 hours, filtered, allowed to stand for 4 hours and cooled to room temperature, and the ethanol was separated.

[0053] The conditions for the composite treatment process are as follows: lanolin is dissolved in 5 times its volume of hot anhydrous ethanol, the extraction temperature is 57°C, the mixture is stirred for 2 hours, filtered, and then allowed to stand for 4 hours and cooled to room temperature to separate the ethanol; then the crude lanolin is heated to 57°C and sent to a vacuum flash evaporation device, where it is contacted countercurrently with hot nitrogen gas at 98°C, and the vacuum degree is -45Kpa.

[0054] The solid content is the solid content detected when lanolin melts, and all samples are tested after being filtered through a pipeline filter.

[0055] Untreated crude lanolin has a color index of 14.7 (APHA color index), a solid content of 1-2%, a strong odor, and is brown in color. + indicates odorless, ++ indicates a slight odor, +++ indicates a distinct odor, and ++++ indicates a strong odor.

[0056] Table 1

[0057]

[0058] As can be seen from Table 1, the deodorization effect of the method of this patent is better than that of the prior art.

[0059] Comparative Example 1

[0060] The process of Comparative Example 1 is basically the same as that of Example 1, except that the exhaust gas from the vacuum flash evaporation equipment in this example is sequentially sent to the condenser, gas-liquid separator, and vacuum equipment. The treated lanolin has a color of 8.8, a pale yellow color, no odor, and a melting point of 39.2°C. The yield is 92.5%. It can be seen that nitrogen gas carries away a large amount of lanolin, resulting in a low lanolin yield.

[0061] Comparative Example 2

[0062] The process of Comparative Example 2 was basically the same as that of Example 1, except that the temperature of the hot nitrogen was 80°C, and the exhaust gas from the vacuum flash evaporator was sequentially sent to the condenser, gas-liquid separator, and vacuum equipment. The treated lanolin had a color of 11.5, a yellow color, a faint odor, a melting point of 39.3°C, and a yield of 94.7%. It can be seen that the lower nitrogen temperature prevented the ethanol from vaporizing quickly, resulting in a higher liquid content of ethanol. At lower temperatures, both decolorization and deodorization were ineffective.

[0063] Comparative Example 3

[0064] The process of Comparative Example 3 was basically the same as that of Example 1, except that the spray temperature of the vacuum flash evaporator was 65°C, and the exhaust gas from the vacuum flash evaporator was sequentially sent to the condenser, gas-liquid separator, and vacuum equipment. After treatment, 3L of ethanol was separated by the first oil-water separator. The treated lanolin had a color of 10.3, was yellow, had a slight odor, a melting point of 39.3°C, and a yield of 94.3%. It can be seen that the high temperature of the spray liquid made the ethanol easily vaporize, resulting in a low ethanol content in the spray liquid in the later stages of processing. This not only resulted in a high proportion of lanolin in the exhaust liquid but also poor decolorization and deodorization effects.

[0065] Comparative Example 4

[0066] The process of Comparative Example 4 was basically the same as that of Example 1, except that: crude lanolin (dissolved in hot ethanol) at 57°C was directly sprayed into a vacuum flash evaporation device without the introduction of hot nitrogen gas. The exhaust gas from the vacuum flash evaporation device was sequentially sent to the condenser, gas-liquid separator, and vacuum equipment. The treated lanolin had a color of 12.1, a yellow color, a slight odor, a melting point of 39.3°C, and a yield of 92.3%. The absence of nitrogen gas presents three problems: first, it cannot remove odorous and pigmented substances in a timely manner; second, the slow ethanol evaporation rate results in a large liquid load and affects the deodorization and decolorization effects; and third, the low temperature leads to poor deodorization and decolorization effects. This results in a deodorization effect that is even worse than vacuum deodorization.

[0067] Comparative Example 5

[0068] The process of Comparative Example 5 was basically the same as that of Example 1, except that: crude lanolin (dissolved in hot ethanol) at 65°C was directly sprayed into a vacuum flash evaporation device (the heating effect was similar to that of hot nitrogen), without introducing hot nitrogen. The exhaust gas from the vacuum flash evaporation device was sequentially sent to the condenser, gas-liquid separator, and vacuum device. In less than three hours, the ethanol was almost completely evaporated; the treated lanolin had a color of 11.5, a yellow color, a slight odor, a melting point of 39.3°C, and a yield of 95.1%. The deodorization effect was similar to that of vacuum deodorization, but the decolorization effect was much worse.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A flash evaporation deodorization method for lanolin, characterized in that, The method includes: S101: Dissolve crude lanolin in 4-6 times its volume of anhydrous hot ethanol, then send it to the upper part of the vacuum flash evaporation equipment and spray it downwards. The temperature of the spray liquid is 50-60℃. S102: Hot nitrogen gas is introduced into the lower part of the vacuum flash evaporation equipment. The temperature of the hot nitrogen gas is 95-105℃ and it is in countercurrent contact with the crude lanolin spray liquid. S103: After circulating and spraying crude lanolin in a vacuum flash evaporation device for 2-5 hours, it is filtered and sent to the first oil-water separator for cooling. After separating ethanol, lanolin is obtained. The heating reactor and the vacuum flash evaporation equipment are connected to form a circulating spray system. The heating reactor is equipped with a stirrer and a first heater. The heating temperature of the heating reactor is 50-60℃. Anhydrous thermal ethanol and crude lanolin are added to the heating reactor according to the formula. The exhaust gas from the vacuum flash evaporation equipment is sequentially sent to the power wave tower, condenser, gas-liquid separator and vacuum equipment. Anhydrous ethanol is circulated and sprayed in the power wave tower, and the temperature of the spray liquid inside is 45-50℃. The vacuum degree of the vacuum flash evaporation equipment is -60 to -30 kPa. The ethanol separated by the first oil-water separator is decolorized by activated carbon and distilled before being sent to a heated reaction vessel for reuse. After the predetermined time, the spray liquid in the power wave tower is output to the second oil-water separator; in the second oil-water separator, the temperature of the liquid is reduced to below 30°C and the lower oil is separated, and the oil is sent to the heating reactor for reuse. The ethanol separated by the second oil-water separator is distilled and then sent to the heating reactor for reuse.

2. The flash deodorization method for lanolin according to claim 1, characterized in that, The condensate separated by the condenser is sent to the power wave tower.

3. The flash deodorization method for lanolin according to claim 1, characterized in that, The vacuum flash evaporation equipment is equipped with a demister at the top and a second heater at the bottom to prevent lanolin from solidifying. Its bottom is connected to the heating reaction vessel and the first oil-water separator through pipelines.

4. The flash deodorization method for lanolin according to claim 1, characterized in that, The condenser has a condensation temperature of 0-10℃.

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