Protein separation, concentration and recovery system

Abstract

The invention belongs to the technical field of protein recovery, and particularly relates to a protein separation, concentration and recovery system which comprises a stock solution pool, a sedimentation module, a concentration module and a sludge storage barrel, an upper-layer stock solution in the stock solution pool flows into the sedimentation module for sedimentation, a precipitated protein solution in the sedimentation module is conveyed into the sludge storage barrel, and a supernatant in the sedimentation module is conveyed into the concentration module; the concentration module is used for filtering small-particle protein in supernate, filtered filtrate is discharged, and high-concentration protein liquid flows into the sedimentation module again; the concentration module comprises a concentration tank, and a plurality of groups of filtering assemblies are arranged in the concentration tank and are used for filtering small-particle protein in supernate; according to the invention, large-particle proteins are firstly separated through the sedimentation module, then small-particle proteins in the supernatant are separated through the concentration module, and the separated low-concentration protein liquid flows into the sedimentation module again to be continuously precipitated, so that the recovery of the proteins in the supernatant is completed.

Description

Technical Field

[0001] The present invention relates to the technical field of protein recovery, and in particular to a protein separation, concentration and recovery system. Background Art

[0002] During the processing and production of corn starch, after corn kernels are soaked in sulfurous acid, crushed, and separated into germ and bran fiber, wet milling is carried out to form a mixed slurry of corn protein and starch. After centrifugation, starch milk and protein slurry (gluten slurry) can be obtained. The starch milk still contains protein and must be washed with water and then centrifuged again to obtain pure starch milk and supernatant containing small proteins; the protein slurry (gluten slurry) is further centrifuged and concentrated to obtain high-concentration gluten slurry and supernatant containing small proteins. The above process respectively recovers corn starch and corn protein, and the two supernatants in the process are collectively referred to as upper-layer stock solution.

[0003] The traditional recovery method for the upper-layer stock solution of corn adopts precipitation to recover protein, but the recovery efficiency is low. The supernatant after precipitation is generally discharged as wastewater. However, the components in the upper-layer supernatant are complex, and it contains some small particle zein that cannot be separated by centrifugation. Its mass percentage in this solution is about 0.5-1%. Although it is much lower than the content of more than 10% in the corn protein slurry separated by centrifugation, its protein purity is higher and its value is relatively greater. Moreover, for the large-scale corn processing industry, its cumulative total cannot be underestimated; therefore, there is very high social and economic value in recovering zein from the upper-layer supernatant. Summary of the Invention

[0004] In view of the deficiencies of the prior art, the present invention provides a protein separation, concentration and recovery system, which can recover the protein in the supernatant of corn starch through a concentration module, overcoming the deficiency of resource waste caused by the direct discharge of the upper-layer supernatant in the prior art.

[0005] To achieve the above technical purpose, the specific technical solution of the present invention is as follows. The present invention provides a protein separation, concentration and recovery system, including: a stock solution tank, a sedimentation module, a concentration module, and a sludge storage bucket; the upper-layer stock solution in the stock solution tank flows into the sedimentation module for sedimentation. The precipitated protein solution in the sedimentation module is transported to the sludge storage bucket, and the supernatant in the sedimentation module is transported to the concentration module; the concentration module is used for filtering small particle proteins in the supernatant. The filtered filtrate is discharged, and the high-concentration protein solution flows back into the sedimentation module; the concentration module includes: a concentration tank, and a plurality of groups of filtering components are arranged in the concentration tank for filtering small particle proteins in the supernatant; the filtering components include a filtrate suction pipe, a concentrated liquid suction pipe, and a cylindrical filter cartridge. The output ends of the filter cartridges are connected to the filtrate suction pipe and the concentrated liquid suction pipe respectively; the filter cartridges are used for concentrating and filtering the supernatant in the concentration tank. After filtration, the high-concentration protein solution is pumped out through the concentrated liquid suction pipe, and the filtrate is pumped out through the filtrate suction pipe.

[0006] As a preferred technical solution of the present invention, a filtration chamber and a filtrate chamber are provided inside the filter cartridge. An inlet and a concentrated liquid outlet are respectively provided on the filtration chamber. The supernatant enters the filtration chamber through the inlet. A filtrate outlet is provided on the filtrate chamber. Among them, the filtrate outlet is connected to a filtrate extraction pipe, and the concentrated liquid outlet is connected to a concentrated liquid extraction pipe.

[0007] As a preferred technical solution of the present invention, a plurality of hollow filter membranes are provided inside the filtration chamber for filtering the supernatant. The upper end of the hollow filter membrane is provided with an open structure and the lower end is provided with a closed structure.

[0008] As a preferred technical solution of the present invention, the upper end of the hollow filter membrane is cast on the top of the filtration chamber and extends into the filtrate chamber, and the lower end of the hollow filter membrane swings freely inside the filtration chamber.

[0009] As a preferred technical solution of the present invention, the filtration chamber is provided with an aeration inlet. Gas enters the filtration chamber through the aeration inlet and is jointly extracted through the concentrated liquid outlet and the high-concentration protein liquid.

[0010] As a preferred technical solution of the present invention, the surface pore size range of the hollow filter membrane is 20nm - 50nm.

[0011] As a preferred technical solution of the present invention, the surface of the hollow filter membrane is provided with hydroxyl and carboxyl groups, and the contact angle between the surface of the hollow filter membrane and water is less than 60 degrees.

[0012] As a preferred technical solution of the present invention, it further includes a pressure filtration module. The high-concentration protein in the sludge storage bucket is transported into the pressure filtration module. The high-concentration protein liquid is pressed into a protein mud cake for recycling through the pressure filtration module, and the filtrate is re-circulated into the original liquid pool.

[0013] The beneficial effects in the present invention are as follows:

[0014] 1. In the present invention, by providing a sedimentation module and a concentration module, the sedimentation module first separates large particle proteins, and then the concentration module separates small particle proteins in the supernatant. The separated low-concentration protein liquid flows back into the sedimentation module to continue precipitation, and the precipitated high-concentration protein is pressed into a filter cake through the pressure filtration module, completing the recovery of proteins in the supernatant.

[0015] 2. The concentration module of the present invention is provided with multiple groups of filtration components. The filtration components are provided with a filter cartridge, a filtrate extraction pipe and a concentrated liquid extraction pipe. A plurality of hollow filter membranes are provided inside the filter cartridge. The hollow filter membranes have a high protein recovery rate and a fast recovery efficiency, and thus can recover the maximum amount of protein molecules in the supernatant. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a protein separation, concentration and recovery system proposed by the present invention.

[0017] Figure 2 This is a schematic structural diagram of the concentration module proposed by the present invention.

[0018] Figure 3 This is a schematic structural diagram of the filtration component of the present invention.

[0019] Figure 4 This is a schematic cross-sectional view of the filter cartridge proposed by the present invention.

[0020] In the figure: 1, raw liquid pool; 2, sedimentation module; 3, concentration module; 31, concentration tank; 32, filtration component; 321, filter cartridge; 3211, filtrate chamber; 3212, concentrated liquid outlet; 3213, clarified liquid outlet; 3214, aeration inlet; 3215, water inlet; 3216, filtration chamber; 3217, hollow filter membrane; 322, clarified liquid suction pipe; 323, concentrated liquid suction pipe; 4, sludge storage bucket; 5, pressure filtration module. Detailed implementation manners

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0022] Embodiment 1: This embodiment discloses a protein separation, concentration and recovery system, as Figure 1 shown, including: a raw liquid pool 1, a sedimentation module 2, a concentration module 3, a sludge storage bucket 4 and a pressure filtration module 5; the upper-layer raw liquid after corn separation is collected in the raw liquid pool 1, and the upper-layer raw liquid in the raw liquid pool 1 flows into the sedimentation module 2 for sedimentation. Among them, the sedimentation module 2 is an inclined plate sedimentation tank or an inclined tube sedimentation tank. Large particles of protein sink to the bottom of the sedimentation module 2 to form a high-concentration precipitated protein solution, and the precipitated protein solution is transported to the sludge storage bucket 4 to form high-concentration protein. Small particles of protein in the sedimentation module 2 are transported to the concentration module 3 along with the supernatant; the concentration module 3 further filters the small particles of protein in the supernatant, and the filtered clarified liquid is directly discharged. After filtration, the small particles of protein adhere together to form large particle flocs, and the large particle flocs flow back into the sedimentation module 2 together with the liquid in the concentration module to form a high-concentration protein solution, and the large particle flocs and large particles of protein are sedimented together to form a cycle; among them, the high-concentration protein in the sludge storage bucket 4 is transported to the pressure filtration module 5, and the pressure filtration module 5 uses a frame plate type filter press. The high-concentration protein is pressed into a protein mud cake for recovery by the pressure filtration module 5, and the filtrate filtered out is re-circulated to the raw liquid pool 1. The filtrate contains a small amount of protein molecules and enters the sedimentation module again for sedimentation to achieve the maximum recovery of protein in the upper-layer raw liquid.

[0023] As Figures 2-3As shown in the figure, the concentration module 3 includes: a concentration tank 31, the bottom of the concentration tank 31 is in a funnel shape, and multiple groups of filter components 32 are arranged in the concentration tank 31 for filtering small particle proteins in the supernatant; the filter component 32 includes a filtrate extraction pipe 322, a concentrated liquid extraction pipe 323, and a cylindrical filter cartridge 321. The output ends of the filter cartridges 321 are all connected to the filtrate extraction pipe 322 and the concentrated liquid extraction pipe 323. Both the filtrate extraction pipe 322 and the concentrated liquid extraction pipe 323 are connected to an external water pump to provide power through the water pump; among them, the filter cartridge 321 is used for concentrating and filtering the supernatant in the concentration tank 31. After filtration, the high-concentration protein liquid is extracted through the concentrated liquid extraction pipe 323, and the filtrate is extracted through the filtrate extraction pipe 322. After the high-concentration protein liquid is extracted, it is transported to the sedimentation module 2 for further sedimentation, and the filtrate is directly discharged after being extracted.

[0024] As Figure 4 shown in the figure, a filtration chamber 3216 and a filtrate chamber 3211 are arranged in the filter cartridge 321. The filtrate chamber 3211 is arranged above the filtration chamber 3216. Several hollow filter membranes 3217 are arranged in the filtration chamber 3216 for filtering the supernatant. The cross-section of the hollow filter membrane 3217 is circular. Hydroxyl and carboxyl groups are arranged on the surface of the hollow filter membrane 3217. The contact angle between the surface of the hollow filter membrane 3217 and water is lower than 60 degrees, which can prevent protein adhesion and pollution and avoid blocking the pores on the surface of the hollow filter membrane 3217. The upper end of the hollow filter membrane 3217 is an open structure, and the lower end is a closed structure. The upper end of the hollow filter membrane 3217 is cast on the top of the filtration chamber 3216 and extends into the filtrate chamber 3211, and the lower end of the hollow filter membrane 3217 swings freely in the filtration chamber 3216. The method for closing the hollow filter membrane 3217 can be hot melt pressing sealing or the method of dripping PVDF organic solution and then soaking in water for curing; among them, the length of the hollow filter membrane 3217 is about 1 meter, the surface pore diameter is 20 - 50nm, and the hollow filter membrane 3217 can withstand a water temperature of not less than 55°C; an inlet 3215 and a concentrated liquid outlet 3212 are respectively arranged on the filtration chamber 3216, and a filtrate outlet 3213 is arranged on the filtrate chamber 3211. Among them, the filtrate outlet 3213 is connected to the filtrate extraction pipe 322, and the concentrated liquid outlet 3212 is connected to the concentrated liquid extraction pipe 323; the supernatant enters the filtration chamber 3216 through the inlet 3215, and the supernatant flows from bottom to top in the filtration chamber 3216. During the flowing process, the supernatant is filtered through the hollow filter membrane 3217. After filtration, the filtrate enters the filtrate chamber 3211 from the upper end opening of the hollow filter membrane 3217, and small particle proteins adhere to the surface of the hollow filter membrane 3217 to form larger flocs, which are extracted from the concentrated liquid outlet 3212 through the concentrated liquid extraction pipe 323 at regular intervals.

[0025] Preferably, the filtration chamber 3216 is provided with an aeration inlet 3214, which is connected to an external air pipe. Gas enters the filtration chamber 3216 through the aeration inlet 3214 and is withdrawn together with the high-concentration protein solution through the concentrated liquid outlet 3212. Among them, the liquid protein content in the supernatant after concentration entering the sedimentation module 2 is not less than 2%, and finally it is discharged into the sludge storage bucket 4. Finally, the liquid containing high-concentration protein particles in the sludge storage bucket 4 is pumped into a plate and frame filter press to be pressed into a mud cake, and the protein separation, concentration and recovery process is completed.

[0026] Example 2: Using the recovery system of Example 1 of the present invention above, the upper-layer stock solution in the process of a corn starch production enterprise was experimented on. A hollow filter membrane 3217 with a pore size of 50 nm was used to filter the upper-layer stock solution. Equal weights of the upper-layer stock solution (the total dry matter content in the upper-layer stock solution is about 1.9 - 2.4%, among which, the zein accounts for 0.3 - 1%; the saccharide substances account for 0.5 - 0.8%, and the rest are fat, salt, lactic acid, amino acids, etc.) and the filtrate were taken respectively, and after drying treatment, the dry matter was obtained. Multiple groups of experiments were carried out, and the percentage of the dry matter content was detected to obtain M in and M out , and the difference M p =M in -M out (M p is the mass percentage of zein concentrated and separated from the upper-layer stock solution). Multiple groups of experimental data are shown in Table 1 below. Table 1 is the experimental data of the zein recovery amount: Table 1 Serial number <![CDATA[Original solution dry matter M in (%)]]> <![CDATA[Filtered liquid dry matter M out (%)]]> <![CDATA[Recovery amount M p (%)]]> 1 3.1 2.3 0.8 2 2.75 2.11 0.64 3 2.7 2.47 0.23 4 3.06 2.74 0.32 5 2.61 2.26 0.35 6 2.98 2.09 0.89 7 2.9 2.2 0.7 8 2.92 2.18 0.74 9 2.51 2.07 0.44 10 3.1 2.7 0.4 11 3.4 2.3 1.1 12 3.41 2.4 1.01 13 3.47 2.59 0.88 14 3 2.7 0.3 15 3 2.6 0.4 16 3 2.3 0.7 17 3.27 2.96 0.31 18 3.01 2.7 0.31 19 2.8 2.4 0.4 20 3.4 3 0.4 21 3.8 2.7 1.1 22 2.4 2 0.4 23 2.3 2 0.3 24 2.3 1.7 0.6 25 2.2 1.7 0.5 26 2.3 1.9 0.4 27 2.3 1.6 0.7 28 2.4 2 0.4 29 2.3 1.6 0.7 30 2.4 2 0.4 31 2.35 2.12 0.23 32 3.5 2.7 0.8 33 3.3 2.5 0.8 34 3.07 2.56 0.51 35 3 2.5 0.5 36 3.1 2.3 0.8 37 2.4 1.6 0.8 38 2.7 2.2 0.5 39 2.34 2.07 0.27 40 2.6 2.1 0.5 From the above Table 1, it can be calculated that by using the recovery system of the present invention, the average value of the recovery rate M p of zein is about 0.56%, which is equivalent to recovering about 5.6 kg of zein per ton of the upper-layer stock solution, which not only solves the problem of resource waste but also solves the problem of environmental pollution.

[0027] Example 3: Using the recovery system of Example 2 of the present invention above, a hollow filter membrane 3217 with a pore size of 50 nm was used to filter the upper-layer stock solution, and then equal weights of the upper-layer stock solution and the filtrate were taken and filtered repeatedly until a filter cake was formed and the filtered water was clear. Multiple groups of experiments were carried out, and the filter cake after the upper-layer stock solution was dried and the weight W in was recorded, and the filter cake after the filtrate was filtered was dried and the weight W f was recorded. The recovery rate is Rec, where, The experimental data are shown in Table 2 below. Table 2 is the experimental data of the zein recovery rate: Table 2 Serial number <![CDATA[Weight of gliadin in the stock solution (g / ml) W in > <![CDATA[Weight (g / ml) of gliadin in the filtrate W f > <![CDATA[Recovery rate R ec (W in -W f ) / W in * 100%]]> 1 0.0305 0.0029 99.62 2 0.248 0.0081 96.73 3 0.0316 0.0102 98.71 4 0.0502 0.0206 98.36 5 0.0986 0.0073 99.70 6 0.0498 0.004 99.68 7 0.0453 0.0065 99.43 8 0.032 0.0099 98.76 9 0.0597 0.0069 99.54 10 0.0552 0.0229 98.34 11 0.0772 0.0063 99.67 12 0.0213 0.0284 94.67 13 0.0456 0.0063 99.45 14 0.0341 0.0032 99.62 15 0.03217 0.004 99.55 16 0.0596 0.0066 99.56 17 0.0586 0.0039 99.73 18 0.0328 0.013 98.41 19 0.0497 0.0083 99.33 20 0.0268 0.0035 99.48 21 0.0244 0.0034 99.44 22 0.025 0.0041 99.34 23 0.0264 0.0102 98.45 24 0.0323 0.0103 98.72 25 0.0331 0.0102 98.77 26 0.0217 0.0064 98.82 27 0.0188 0.0037 99.21 As can be calculated from Table 2 above, the average recovery rate of the upper-layer stock solution alcohol-soluble protein using the recovery system of the present invention is about 99%, and the recovery efficiency of the protein is extremely high.

[0028] Finally, it should be noted that: in the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "vertical", "upper", "lower", "horizontal", etc. is based on the orientation or positional relationship shown in the drawings, and 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 operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0029] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A protein separation, concentration and recovery system, characterized in that, Including: Raw liquid pool (1), sedimentation module (2), concentration module (3) and sludge storage bucket (4); The upper-layer raw liquid in the raw liquid pool (1) flows into the sedimentation module (2) for sedimentation. The precipitated protein liquid in the sedimentation module (2) is transported into the sludge storage bucket (4), and the supernatant in the sedimentation module (2) is transported into the concentration module (3); The concentration module (3) is used to filter small-particle proteins in the supernatant. The filtered filtrate is discharged, and the high-concentration protein liquid flows back into the sedimentation module (2); The concentration module (3) includes: a concentration pool (31). A plurality of filter components (32) are provided in the concentration pool (31) for filtering small-particle proteins in the supernatant. The filter component (32) includes a filtrate extraction pipe (322), a concentrated liquid extraction pipe (323) and a cylindrical filter cartridge (321). The output ends of the filter cartridges (321) are connected to the filtrate extraction pipe (322) and the concentrated liquid extraction pipe (323); The filter cartridge (321) is used to concentrate and filter the supernatant in the concentration pool (31). After filtration, the high-concentration protein liquid is extracted through the concentrated liquid extraction pipe (323), and the filtrate is extracted through the filtrate extraction pipe (322); A filter chamber (3216) and a filtrate chamber (3211) are provided in the filter cartridge (321). An inlet (3215) and a concentrated liquid outlet (3212) are respectively provided on the filter chamber (3216). The supernatant enters the filter chamber (3216) through the inlet (3215). A filtrate outlet (3213) is provided on the filtrate chamber (3211). Among them, the filtrate outlet (3213) is connected to the filtrate extraction pipe (322), and the concentrated liquid outlet (3212) is connected to the concentrated liquid extraction pipe (323); A number of hollow filter membranes (3217) are provided in the filter chamber (3216) for filtering the supernatant. The upper end of the hollow filter membrane (3217) is of an open structure, and the lower end is of a closed structure.

2. The protein separation, concentration and recovery system according to claim 1, wherein The upper end of the hollow filter membrane (3217) is cast on the top of the filter chamber (3216) and extends into the filtrate chamber (3211), and the lower end of the hollow filter membrane (3217) swings freely in the filter chamber (3216).

3. The protein separation, concentration and recovery system according to claim 2, characterized in that, The filter chamber (3216) is provided with an aeration inlet (3214). Gas enters the filter chamber (3216) through the aeration inlet (3214) and is extracted together with the high-concentration protein liquid through the concentrated liquid outlet (3212).

4. The protein separation, concentration and recovery system according to claim 3, wherein, The surface pore size range of the hollow filter membrane (3217) is 20nm - 50nm.

5. The protein separation, concentration and recovery system according to claim 4, characterized in that, Hydroxyl and carboxyl groups are provided on the surface of the hollow filter membrane (3217), and the contact angle between the surface of the hollow filter membrane (3217) and water is less than 60 degrees.

6. The protein separation, concentration and recovery system according to claim 5, wherein, It further includes a pressure filtration module (5). The high-concentration protein in the sludge storage bucket (4) is transported into the pressure filtration module (5). The high-concentration protein liquid is pressed into a protein mud cake for recovery by the pressure filtration module (5), and the filtrate flows back into the raw liquid pool (1).

Images