Recycling treatment method of traditional Chinese medicine alcohol precipitation precipitate

Abstract

The invention provides a recovery treatment method of traditional Chinese medicine alcohol precipitation precipitates, and aims to efficiently recover ethanol in precipitates generated in a traditional Chinese medicine water extraction and alcohol precipitation process and carry out solid-liquid separation treatment on the precipitates. The method comprises the following steps: adjusting the pH value of a precipitate, and adding a proper amount of NaOH to reduce the viscosity; diatomite is added to improve fluidity; after stirring and mixing, realizing solid-liquid separation by adopting membrane filter pressing; and carrying out vacuum concentration on the filter-pressed liquid to recover the ethanol, and rectifying and purifying the recovered ethanol through a rectifying tower to achieve the ethanol concentration of 95% or above. And the recovered solid precipitate and other medicine residues are treated together, so that centralized transportation and discharge are facilitated. The method can avoid precipitate gelatinization, improve the recovery rate of ethanol, reduce the production cost and realize resource utilization of wastes. The method has the characteristics of simplicity in operation, environmental protection and energy conservation, and is suitable for treatment of precipitates generated by water extraction and alcohol precipitation and ethanol recovery in the traditional Chinese medicine production process.

Description

Technical Field

[0001] The invention belongs to the technical field of pharmaceuticals and relates to a recovery and treatment method for alcohol precipitation of traditional Chinese medicine. Background Art

[0002] In the production process of Chinese patent medicine, water extraction and alcohol precipitation are usually used to remove some impurities that are not effective ingredients, so as to achieve the purpose of refining. However, in the process of water extraction and alcohol precipitation, a large amount of ethanol-insoluble precipitates will be produced. The dry and wet state and the amount of precipitation vary greatly depending on the variety, but these precipitates are not effective ingredients and need to be removed. Because the precipitate also contains a large amount of ethanol, direct discharge will not only cause a waste of resources, but also cause pollution and damage the ecological environment.

[0003] At present, most Chinese medicine production companies are facing this technical problem. The usual method is to discharge directly or vacuum-concentrate the precipitate and then collect a small amount of alcohol. However, neither of these two methods can really solve the problem, because the alcohol precipitation of Chinese medicine contains a lot of alcohol. Direct discharge to the sewage treatment station will cause a sharp increase in the COD value of the sewage, and it will not be able to properly treat the production waste water, which will bring serious environmental problems. At the same time, it will also cause the alcohol in the precipitate to be wasted. There are many flocculent substances in the precipitate, which contain a large amount of polysaccharides and starch substances. It is easy to gelatinize when directly concentrated and recovered by vacuum, and the alcohol in the precipitate cannot be well separated. After recovery, a large amount of gelatinized starch and sugar substances stick to the vacuum concentrator, which is difficult to clean. The recovery efficiency is low and the production cost is high. The precipitate paste after recovery is still in a liquid state and still cannot be discharged directly.

[0004] Based on the above reasons, it is urgent to find a method for treating the precipitate produced in the water extraction and alcohol precipitation process. The method needs to ensure that the ethanol in the precipitate can be recycled and reused while protecting the environment, truly turning waste into treasure and saving energy and reducing emissions. Summary of the invention

[0005] In view of this, the purpose of the present invention is to solve the above-mentioned problems and provide a recovery and treatment method for traditional Chinese medicine alcohol precipitation, which can maximize the recovery and utilization of ethanol in the precipitate produced during the water extraction and alcohol precipitation of traditional Chinese medicine, and at the same time, solidify the truly useless precipitate to achieve solid-liquid separation, facilitate transportation and treatment, and ultimately achieve the purpose of turning waste into treasure and saving energy and reducing emissions.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A method for recovering and treating a Chinese medicine alcohol precipitation precipitate, comprising the following steps:

[0008] S1. Adjust the pH value: transfer the precipitate into a mixing tank with a stirring paddle, adjust the pH value of the precipitate with an appropriate amount of NaOH, stir while adding, and reduce the viscosity of the precipitate;

[0009] S2. Add diatomaceous earth: Add appropriate amount of diatomaceous earth to increase the filterability of precipitation;

[0010] S3, mixing: fully stir the precipitate with NaOH and diatomaceous earth, turn on the stirring paddle, control the stirring speed at 35-60 rpm, stir for 10 minutes to mix it evenly;

[0011] S4, diaphragm filter pressing: The mixed precipitate is transferred to the filter press feed pump through a pneumatic diaphragm pump and transported into each filter chamber for diaphragm filter pressing to achieve solid-liquid separation;

[0012] S5, vacuum recovery: the liquid filtered out by the diaphragm is concentrated and ethanol is recovered by a vacuum concentrator, the vacuum pressure of the vacuum concentrator is controlled at -0.04~-0.08Mpa, and the steam pressure is ≤0.2Mpa;

[0013] S6, distillation: the recovered ethanol is transferred to a distillation tower for distillation to remove impurities. During the distillation process, the steam pressure is controlled to be below 0.15MPa, the temperature is 80-84°C, and the pressure in the kettle is below 0.05MPa. During the operation, the concentration of ethanol after condensation is checked. When the ethanol concentration is ≥95%, it is slowly placed in a high alcohol storage tank through a cooler. If the concentration is not enough, it is refluxed to the kettle through a buffer and then distilled again. The ethanol in the kettle is repeatedly distilled to an alcohol content of less than 10% (20°C) and then discharged;

[0014] S8, slag removal: The solid precipitate residue after membrane filtration, the recovered precipitate residue and the medicinal residue produced by extraction are recovered and discharged together.

[0015] Preferably, in step S1, 15-18 kg of NaOH is used for every 1000 L of precipitation, and the pH value is controlled at 10-12.

[0016] Preferably, in step S2, 16-20 kg of diatomaceous earth is used for every 1000 L of precipitation, and the diatomaceous earth is added while stirring.

[0017] Preferably, in step S4, the pump pressure is controlled at 0.4-0.5 MPa, the pressure between the filter plates is controlled at 22-25 MPa, and the precipitate in the mixing tank needs to be kept stirred by the stirring paddle to prevent uneven stratification and mixing of the precipitate.

[0018] Preferably, in step S6, during the reflux and distillation of ethanol, the interlayer pressure during reflux is controlled to be below 0.05 MPa, and the pressure in the tank is controlled to be below 0.02 MPa.

[0019] The beneficial effects of the present invention are:

[0020] 1. The present invention adopts membrane filter pressing technology, which can fully separate the liquid in the precipitate from the solid, avoiding the gelatinization of the precipitate in the traditional vacuum concentration method. The solid precipitate after filter pressing is a relatively dry solid, which is convenient for transportation and centralized treatment, avoiding the treatment difficulties that may be caused by direct discharge of liquid precipitate. The solid drug residue can be further mixed with other drug residues for recycling and treatment, reducing the total amount of waste and realizing centralized management of waste.

[0021] 2. The present invention adds NaOH and diatomaceous earth during the precipitation process, which effectively reduces the viscosity and gelatinization risk of the precipitate, ensures a smooth filter press process, and uses a mixing tank with a stirring paddle to ensure that the precipitate is evenly mixed to prevent stratification from affecting the filtration efficiency. Through vacuum concentration combined with distillation, the purity of ethanol in the recovery process can reach more than 95%. The pressure and temperature are controlled in the vacuum recovery stage, which effectively avoids the loss of ethanol volatilization and improves the recovery efficiency of ethanol. A circulating reflux system is set during the distillation process to ensure repeated purification of ethanol, reduce ethanol waste, and improve reuse efficiency. High-purity ethanol can be re-invested in the production process, reducing the additional procurement cost of alcohol and reducing enterprise operating expenses.

[0022] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0024] Figure 1 The figure is a schematic flow chart of the recovery and treatment method of the traditional Chinese medicine alcohol precipitation in the present invention. DETAILED DESCRIPTION

[0025] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0026] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0027] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is 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 operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0028] See also Figure 1 , is a process flow of a recovery and treatment method of a traditional Chinese medicine alcohol precipitation, the method comprising the following steps:

[0029] S1. Adjust the pH value: transfer the precipitate into a mixing tank with a stirring paddle, and use an appropriate amount of NaOH to adjust the pH value of the precipitate. Use 15-18 kg of NaOH for every 1000 L of precipitate to control the pH value at 10-12; stir while adding to reduce the viscosity of the precipitate;

[0030] S2. Add diatomaceous earth: Add appropriate amount of diatomaceous earth to increase the filterability of the sedimentation; use 16-20 kg of diatomaceous earth for every 1000 L of sedimentation, and stir while adding.

[0031] S3, mixing: fully stir the precipitate with NaOH and diatomaceous earth, turn on the stirring paddle, control the stirring speed at 35-60 rpm, stir for 10 minutes to mix it evenly;

[0032] S4, diaphragm filter press: the mixed precipitate is transferred to the filter press feed pump through a pneumatic diaphragm pump and transported into each filter chamber for diaphragm filter press to achieve solid-liquid separation; during the operation, the pump pressure is controlled at 0.4-0.5Mpa, and the pressure between the filter plates is controlled within 22-25Mpa. The precipitate in the mixing tank needs to be kept in a stirring state with a stirring paddle to prevent uneven stratification and mixing of the precipitate.

[0033] S5, vacuum recovery: the liquid filtered out by the diaphragm is concentrated and ethanol is recovered by a vacuum concentrator, the vacuum pressure of the vacuum concentrator is controlled at -0.04~-0.08Mpa, and the steam pressure is ≤0.2Mpa;

[0034] S6, distillation: the recovered ethanol is transferred to a distillation tower for distillation to remove impurities. During the distillation process, the steam pressure is controlled to be below 0.15MPa, the temperature is 80-84°C, and the pressure in the kettle is below 0.05MPa. During the operation, the concentration of ethanol after condensation is checked. When the ethanol concentration is ≥95%, it is slowly placed in a high alcohol storage tank through a cooler. If the concentration is not enough, it is refluxed to the tower kettle through a buffer and then distilled. During the ethanol reflux and distillation process, the interlayer pressure is controlled to be below 0.05MPa during reflux, and the pressure in the tank is controlled to be below 0.02MPa; the ethanol in the kettle is repeatedly distilled to an alcohol content of less than 10% and then discharged;

[0035] S8, slag removal: The solid precipitate residue after membrane filtration, the recovered precipitate residue and the medicinal residue produced by extraction are recovered and discharged together.

[0036] In the specific implementation process, different parameters were compared with respect to pH value, diatomaceous earth addition ratio, stirring method, and stirring frequency, as shown in the table below.

[0037] Table 1

[0038] serial number Precipitation and NaOH addition ratio pH Solid-liquid separation ratio Recovery rate of ethanol precipitation 1 Not Joined 5～7 Cannot be separated 0 2 1:(0.012～0.014) 7～9 50％ 24％ 3 1:(0.015～0.018) 10～112 70％ 35％

[0039] As shown in Table 1, when no solid NaOH is added, the viscosity of the precipitate is large, the diaphragm filter press resistance is large, the filter press operation cannot be performed, the solid-liquid separation cannot be achieved, and the ethanol recovery rate is the lowest; when solid NaOH is added to the precipitate, the pH value is controlled at 7-9, the ratio of precipitate to solid NaOH is about 1:(0.012-0.014), the viscosity of the precipitate is slightly reduced, the filter press resistance is slightly reduced, the solid-liquid separation ratio is slightly increased, and the precipitated ethanol recovery rate is higher; when solid NaOH is added to the precipitate, the pH value is controlled at 10-12, the ratio of precipitate to solid NaOH is about 1:0.016, the precipitate viscosity is significantly reduced, the filter press resistance is reduced, the solid-liquid separation ratio reaches the maximum, and the precipitated ethanol recovery rate is the highest.

[0040] Table 2

[0041]

[0042]

[0043] As shown in Table 2, when diatomite is not added, the fluidity of the precipitate is poor, the resistance of the membrane filter press is large, the filter press operation cannot be performed, the solid-liquid separation cannot be achieved, and the ethanol recovery rate is the lowest; when the ratio of diatomite added is 1:0.012, the resistance of the membrane filter press is slightly reduced, but the solid-liquid separation ratio is still very low, and the ethanol recovery rate is low; when the ratio of diatomite added is 1:(0.016-0.020), the fluidity of the precipitate is good, the solid-liquid separation ratio of the membrane filter press can reach up to 70%, and the ethanol recovery rate is high; when the diatomite dosage ratio continues to increase to 1:0.025, the solid-liquid separation ratio of the membrane filter press no longer changes significantly, and the ethanol recovery rate in the precipitate no longer increases.

[0044] Table 3

[0045] serial number Mixing method Solid-liquid separation ratio Recovery rate of ethanol precipitation 1 Mixing method 1 Cannot be separated 0 2 Mixing method 2 40％ 20％ 3 Mixing method 3 70％ 35％

[0046] As shown in Table 3, when solid NaOH and diatomaceous earth are added and stirred together for 10 minutes (stirring mode 1), it is found that the stirring resistance is large, the existing equipment cannot stir evenly, the membrane filter pressing operation cannot be completed, and solid-liquid separation cannot be achieved; when the stirring paddle is opened for stirring when solid NaOH and diatomaceous earth are added, stirring is continued for 10 minutes after the diatomaceous earth is added, and stirring is stopped (stirring mode 2), and membrane filter pressing is performed, which can achieve partial solid-liquid separation, but the precipitation in the blending tank begins to settle again without stirring, and the filter pressing effect deteriorates in the later stage, the solid-liquid separation ratio is low, and the precipitated ethanol recovery rate is not high; when the stirring paddle is opened for stirring when solid NaOH and diatomaceous earth are added, stirring is continued for 10 minutes after the diatomaceous earth is added, and the membrane filter pressing is performed. During the filter pressing process, the precipitation in the blending tank is kept in a stirring state (stirring mode 3) until the filter pressing is completed, the filter pressing effect is good, the solid-liquid separation ratio is the highest, and the ethanol recovery rate in the precipitate is also the highest.

[0047] Table 4

[0048] serial number Stirring speed (rpm) Solid-liquid separation ratio Recovery rate of ethanol precipitation 1 35 70％ 35％ 2 45 70％ 35％ 3 55 70％ 35％ 4 60 70％ 35％

[0049] It can be seen from Table 4 that when the rotation speed is controlled between 35 and 60 rpm, the solid-liquid separation ratio of the membrane filter press is very high and the ethanol recovery rate is also consistent, which proves that the stirring frequency can ensure uniform mixing within this range.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A method for recovering and treating a Chinese medicine alcohol precipitation, characterized in that: The steps include: S1. Adjust the pH value: transfer the precipitate into a mixing tank with a stirring paddle, adjust the pH value of the precipitate with an appropriate amount of NaOH, stir while adding, and reduce the viscosity of the precipitate; S2. Add diatomaceous earth: Add appropriate amount of diatomaceous earth to increase the filterability of precipitation; S3, mixing: fully stir the precipitate with NaOH and diatomaceous earth, turn on the stirring paddle, control the stirring speed at 35-60 rpm, stir for 10 minutes to mix it evenly; S4, diaphragm filter pressing: The mixed precipitate is transferred to the filter press feed pump through a pneumatic diaphragm pump and transported into each filter chamber for diaphragm filter pressing to achieve solid-liquid separation; S5, vacuum recovery: the liquid filtered out by the diaphragm is concentrated and ethanol is recovered by a vacuum concentrator, the vacuum pressure of the vacuum concentrator is controlled at -0.04~-0.08Mpa, and the steam pressure is ≤0.2Mpa; S6, distillation: the recovered ethanol is transferred to a distillation tower for distillation to remove impurities. During the distillation process, the steam pressure is controlled to be below 0.15MPa, the temperature is 80-84°C, and the pressure in the kettle is below 0.05MPa. During the operation, the concentration of ethanol after condensation is checked. When the ethanol concentration is ≥95%, it is slowly placed in a high alcohol storage tank through a cooler. If the concentration is not enough, it is refluxed to the tower kettle through a buffer and then distilled again. The ethanol in the kettle is repeatedly distilled to an alcohol content of less than 10% and then discharged; S7, slag removal: The solid precipitate residue after membrane filtration, the recovered precipitate residue and the medicinal residue produced by extraction are recovered and discharged together.

2. The method for recovering the Chinese medicine alcohol precipitation according to claim 1, characterized in that: In step S1, 15-18 kg of NaOH is used for every 1000 L of precipitation, and the pH value is controlled at 10-12.

3. The recovery and treatment method of the Chinese medicine alcohol precipitation according to claim 1, characterized in that: In step S2, 16-20 kg of diatomaceous earth is added for every 1000 L of precipitation while stirring.

4. The method for recovering the Chinese medicine alcohol precipitation according to claim 1, characterized in that: In step S4, during the operation, the pump pressure is controlled at 0.4-0.5 MPa, the pressure between the filter plates is controlled at 22-25 MPa, and the precipitate in the mixing tank needs to be kept stirred by the stirring paddle to prevent uneven stratification and mixing of the precipitate.

5. The method for recovering the Chinese medicine alcohol precipitation according to claim 1, characterized in that: In step S6, during the ethanol reflux and distillation process, the interlayer pressure during reflux is controlled to be below 0.05 MPa, and the pressure in the tank is controlled to be below 0.02 MPa.

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