JPH07502312A - Apparatus and method for producing fibrous starch raw material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Apparatus and method for producing fibrous starch raw material The present invention provides a method for producing fibrous starch, especially paper. and related to equipment and manufacturing methods for manufacturing those used in the manufacture of paperboard. Ru.

An aqueous colloidal dispersion of starch, typically at a concentration of 5 to 40% by weight, is prepared in a non-solvent (e.g. (e.g. ammonium sulfate salt solution), it aggregates and forms gel flakes. is known to form.

U.S. Pat. No. 4,205,025 discloses that a starch containing substantially water-soluble starch is There is. The term “fibril J” refers to a hybrid form between a film and a fiber. is intended to indicate. The film-forming polymer is dissolved in water to form a solution. , this solution is then precipitated while applying shear stress to form fibrils. injection into a solvent, preferably an organic non-solvent, such as an alcohol or a ketone; rice in which the lever fibrils are made more hydrophobic by subsequent treatment in an insolubilizing agent National Patent No. 4,340.422 discloses that in order to improve the hydrophobicity of fibrils, High amylose content (50% A method of forming fibrils using starch insoluble content in water containing ~80% by weight) is listed. The above starch, which is substantially insoluble in water, is It requires a step of dissolving in a potash solution, and this alkaline solution solves various problems during the flocculation step. for the removal of sulfate salts different from the ammonium salts produced in the above steps. This causes problems related to

U.S. Pat. No. 4,139,699 discloses that a copolymer with high amylopectin content A raw material with starch fiber morphology is produced by extruding a loid starch dispersion into a flocculant. describes a method for producing the product. Contains less than about 95% amylopectin When using starch, ensure that the starch is a colloidal dispersion in the aqueous system. starch must be chemically modified to must be dissolved in the presence of chemical substances.

The use of alkaline hydroxides, especially sodium hydroxide, makes it difficult to use ammonium sulfate. Ammonia is produced in the flocculation step carried out using The above method has been used industrially in that it prevents agglomeration and creates disposal problems. make it difficult to apply.

U.S. Patent No. 4,243,480 By conventional papermaking techniques using products manufactured by the methods described in the specifications. Describes the method of manufacturing paper or paperboard. The above product aggregates and moves through the cap 10 to 500 microns in diameter and length manufactured by extruding into a bath. It is in the form of short fibers with a diameter of 0.1 to 3 mm.

U.S. Pat. No. 4,853,168 discloses a colloidal starch application for extrusion. The dispersion is obtained by boiling an aqueous starch dispersion containing an aqueous salt solution for flocculation. A method of the type described in US Pat. No. 4,139,699 is described.

In the above patent literature and practical experience, starch dispersions or suspensions are finely divided. Various known devices, e.g. For example, a spray nozzle, a mixer with an ejector-1 stirrer, a spinneret or a syringe, etc. Can be used. However, the equipment used in this kind of It has been empirically shown that it has a strong influence on the properties of Starch in highly turbulent conditions Conditional agglomeration device (e.g. ejector) or orderly velocity profile If the device does not have a flat scale (rolled up) Otherwise, starch collapses to some extent while forming three-dimensional aggregates.

The dimensions of these non-fibrous products vary with operating conditions and their properties have an influence on In the manufacturing process, fine particles are lost during separation, and These clog the cloth, slowing down the filtration process. used in paper making In some cases, the resulting loss of starch in the paper and increase in COD in paper mill effluents With this, these fine particles are not retained on the flat cloth. On the other hand, giant grains This brings about disadvantages in papers produced without integration with cellulose matrix fibers. vinegar.

Another negative aspect identified in the fibrils obtained by the aforementioned method is that High water retention and solubility values.

A further product obtained by the agglomeration method but having a fibrous morphology is a product whose fibrous structure is Thanks to its affinity with cellulose fibers increases and its lower surface area makes it more Part of the above drawbacks are that it reduces water retention in that it is easy to filter and reduces its solubility. decrease.

It is therefore suitable for the manufacture of paper and paperboard and in addition to corn or For starch used from low-cost starch such as starch from potatoes, an alkaline solution of starch is added. have dimensions, size distribution and physicochemical properties that could be obtained without It would be desirable to produce a product that has a fiber morphology that

In view of this objective, the subject of the present invention is a dispersion of a starch raw material in a brine flocculant or A method for producing a fibrous starch raw material by extrusion of an aqueous solution, comprising: - forming a microporous tubular wall; Surrounding the starch raw material concentrically with the above micropore walls in such a way as to obtain a flux of extrusion Pushing the dispersion or aqueous solution through a microporous tubular wall in a ring-wound chamber operations and - pressing by supplying a flow of flocculant into an annular chamber parallel to the extrusion surface; Operation to aggregate the performance This method is characterized by the following.

Another object of the invention is - a tubular member consisting of a first inlet means for supplying a flux of starch raw material; , - a supply means for starch raw material connecting said first inlet means; - an annular outlet for starch raw material; room, - arranged coaxially with said outlet chamber and inserted between the tubular member and the supply chamber; The needles of various starch raw materials are extruded through the fine wall in the exit chamber to tubular having a pore wall applied to form an envelope around the tubular member element, A second inlet means and part connecting one outlet chamber for supplying the aggregate flow Textile manufacturing equipment, characterized in that it consists of a discharge means located downstream from the outlet chamber. It is a place.

By using the method and apparatus of the present invention, it is possible to [Anthrone test] e5t) Has water solubility and water retention of less than about 2% as measured by J (described below) We have found that it is possible to obtain the product. Method, device and invention of the invention Further advantages and characteristics of the product obtained are explained in detail on the basis of the attached drawings. I will clarify.

FIG. 1 shows a flowchart of a plant implementing the method of the invention, and FIG. FIG. 3 is a cross-sectional view of another embodiment of the fiber manufacturing device. 4 is an enlarged detail of a portion of FIGS. 2 and 3; FIG.

In Figure 1, 1 is typically 5 to 50% by weight, preferably 10 to 40% by weight. Dispersion in the If-state for producing starch suspensions in water having a dry weight of % Indicates liquid. The starch used to make the suspension is 30 to 100% amylopectin. natural starches with a high content of minerals, such as corn, rice, tapioca, and potato; Starch is preferred. Particularly preferred is 64 to 80% by weight of typical amino acids. It is a corn starch that is widely sold in the market and contains lopectin content.

Within the scope of the invention, starches with a high amylose content, such as amylomized and chemically or physically modified starches can be used.

The starch suspension may also contain additives such as salts (e.g. U.S. Pat. No. 4.853.1). brine flocculants as described in Specification No. 68), alkaline agents, bulking agents or minerals. , crosslinking agent, plasticizer, polyoxyethylene, polyvinyl alcohol, ionic polymerization copolymers of egg ash and acrylic acid and/or maleic anhydride , polyacrylates, polyamides, lubricants such as lecithin, fatty acids, fatty acids It can also contain esters and amides.

The suspension held in the disperser under stirring at ambient temperature is then pumped through gear pump 2. through the jet steamer t(i (denoted as 3)), where the desired steam Mix in co-current with water vapor in such a way that boiling temperature is reached. The jet steaming method , is known per se, and immediately heats the aqueous suspension in the process stream and then and holding the Itn hot liquid for a predetermined period of time. Generally steaming at 90 to 180°C. The boiling temperature is selected depending on the particular starch used during this process. In particular, temperature, application It is possible to obtain a dispersion close to complete gelation by reliably reducing the shearing time and holding time. While ensuring that Must be careful.

At the outlet of the jet steamer, the starch dispersion or solution to be steamed is Stir in a container and collect while circulating water at a temperature of about 100"C inside the casing. do. A filter is added to release excess water vapor and return the starch/water concentration to near the initial concentration. Do a rush.

From the reactor 4, the starch is pumped via pump 5 into a heat exchanger where about Temperature of 20 to +00°C, preferably 4o to 70"C. Heat exchanger However, the starch is also injected with the brine flocculant described below as described in Figures 2 and 3. supply to type fiber manufacturing equipment. Salts that can be used within the scope of the invention include ammonium sulfate aluminum, magnesium sulfate, aluminum sulfate, ammonium phosphate, sodium chloride lJ +’7m, sodium sulfate, sodium carbonate, sodium bicarbonate and ammonium chloride It is Monium.

reach the saturation level of the above salts and use at concentrations below the saturation level is equally possible, but the aqueous salt solution is a saturated solution of ammonium sulfate.

The starch fiber obtained from the fiber manufacturing equipment is aged and subsequently decanted. The reactor is collected in a stirred reactor 8 for the purpose of recovery. Once decantation is performed, the clarified material condenses. Mixed with a saturated aqueous salt solution of the binder.

The clarified material that circulates in the equipment as a flocculant is a saline solution and, due to its small size, cannot be recycled. Contains undecanted fine fibers in the container.

The fiber mass from reactor 8 is pumped by bomb 10 over Filter II. It will be done. The fibers are then collected in container 12, while the filtrate is fed into container 13, where Subsequently to recover the aqueous brine solution applied to feed the fiber manufacturing device 7 The sulfate is added and then mixed with the clarified material from the pump 9.

By using an appropriate number of ripening and decantation reactors 8, It is possible to carry out the method of the invention continuously, thereby directly applying the A starch is obtained which can be washed or easily filtered and subsequently washed.

The fiber manufacturing bag ft7 in the embodiment of FIG. 2 is capable of supplying starch raw material under normal conditions. at least one inlet 15 for supplying flocculant, an inlet 16 for the purpose of supplying flocculant and and an outlet 17 for discharging the starch fibers produced after agglomeration.

A wall 19 with radial holes is provided from the middle to allow the starch raw material to enter from the inlet 15. It is immersed into the tubular duct 18 in which it is located. Perforated wall member 19 provides starch feed stream It acts as a distributor sending in the direction of room 21.

22, the starch raw material is extruded from the supply chamber 21 into the annular chamber 23 coaxially therewith. A tubular element having microporous walls suitable for use is shown. room 23 is of element 22 The radial outer surface and the radial inner surface of member 14 are separated.

Tubular member 22 is porous with a pore size distribution preferably between 10 and 500 microns. It consists of a sintered metal body.

Alternatively, the tubular element 22 is obtained by mechanical manipulation and preferably Numerous radial through holes with openings having dimensions from 0 to 500 microns It may also be a member made of a metal material, such as stainless steel. Preferably, The radial holes have narrow openings, typically IO to 500 microns. Portion of inlet 24 for starch raw material and opening of larger size, preferably 0. It has a cross section with a portion above the outlet of the starch raw material having a diameter of 5 to 1.5 mm.

Opening density on the extrusion surface (intended as the surface of the tubular element in contact with the flocculant) ) is 4 to 0.05 holes/mm'' expressed as the ratio of the number of holes to the surface area.

The flocculant fed through the inlet opening 16 acts as a distributor. flows through an annular element 26 having a crown of axial holes 27 to a first annular chamber defined by a tubular element coaxial with the wall 14 and the member 29; be done. From the chamber 28, the flow is directed to an outlet 2 parallel to the radial outer surface of the microporous element 22. 3 into an annular chamber where the flow of flocculant interacts with the extrusion flow of starch raw material. let

The flow velocity of the salt water flocculant in the annular cross section of the exit chamber 23 is maintained at 1 to 15 m/s. It is preferable to do so.

Flow rate of flocculant in the annular cross section of chamber 23 and starch source at the exit of the hole in the micropore wall The intended withdrawal ratio is determined by the ratio of the starch raw material flow rate to the exit hole. (defined as the ratio of the total cross-sectional area to the total cross-sectional area) is generally! -1000. Preferably 100 -1000. such that a starch material residence time of 5 to 15 milliseconds is obtained. The axial length of the exit chamber is preferred. In any case, room 2 where the starch raw material is extracted The axial length of No. 3 must be such that stretching of the starch raw material occurs and complete phase transformation occurs at the same time. Must be.

At the outlet of chamber 23, the displaced flow increases rapidly in the flow direction. It is supplied to the annular chamber 30 in the cross section shown in FIG.

In the embodiment of the fiber manufacturing apparatus shown in FIG. is fed into an annular chamber 32 defined by the wall of the member 14 and the microporous wall tubular element 33. It will be done. The flow of starch raw material flows radially inwardly through the walls of the element 33 and into the tube element 33. It flows into an annular outlet chamber 35 consisting of a central core 35 coaxial with the member. The flocculant flow is flows across the inlet 36 and into the prechamber 37 and across the hole 39 in the annular element 38. flows into chamber 40 and has a narrow cross-section in the flow direction from chamber 40. Flows into exit chamber 34.

In this embodiment, the cross-section of the holes in the microporous elements 33 remains the same as in FIG. this place However, the flow of starch raw material proceeds from a large cross section to a small cross section, and the starch flow rate increases. and necking down of starch needles. bring about wn). The raw material leaving the hole is flocculated by the flocculant in the annular chamber 34. Ru. If the best conditions for agglomeration are a withdrawal ratio of preferably 1 to 150, The release ratio of the starch raw material from the hole into the micropore wall 33 is 0. 1 to 1 m/s.

The fiber manufacturing apparatus main body of the present invention provides distinct advantages, for example as follows.

That is, A product with a fibrous structure is provided through the agglomeration of starch raw materials.

- Its structure with cylindrical symmetry ensures non-uniformity of the hydrodynamic conditions and therefore possible Eliminate sexual border effects.

- Its dimensions and shape are completely known and therefore the project evaluation criteria are valid. Ru.

1) The knowledge of the above evaluation criteria recognizes the expansion of its scale.

The following examples highlight further advantages brought about by using the above textile manufacturing equipment: 1 Using the plant shown in Figure 1, corn starch fibers were produced under the following conditions: obtained by operation.

- Starch concentration in dispersion: 15% by weight (anhydrous starch) - Maximum in jet steamer Steaming temperature: 115°C (preferred temperature range is 100-130°C) - Starch temperature at the inlet of the fiber manufacturing equipment, 60°C - At the inlet of the fiber manufacturing equipment Temperature of the salt aqueous solution and maximum speed of the salt aqueous solution in the exit chamber of the 2-pi C-i fiber manufacturing equipment Degree 7m/s - Flow rate of starch after steaming: 48L/h - Extrusion sintering made of sintered metal with porosity (average diameter of pores) of 40 microns A fiber manufacturing device as shown in FIG. 2 with a body - an exit chamber (23 , 24) Length/IOcm - Average aging time before filtration: 4 hours.

By performing the method according to the above conditions, the viewer The following size distribution (expressed in weight %) measured according to the er　McNejt) apparatus ) was obtained.

595 μm (28 mesh)%: 0.3297 ttmc40 mesh)%: 31149 μm (+00 mesh)% 68.574 μm (200 mesh %: 21.3 Above 200 mesh x 100: 6.8 Measurements of solubility and characteristics of the resulting fibers were performed using the following method: Cleaning the filtration panel from runt: 100 g of filter cake was mechanically stirred using a glass anchor stirrer under the following conditions. Disperse in water (500 ml) by stirring.

Becker with a diameter of 10 cm and a height of 20 cm: mechanical Glass anchor stirrer (length = 40 cm, with stirring blades of length 8 cm, height = 8cm) Temperature = 20°C: Stirring time 30 minutes 1 rotation speed 500 rpm).

The resulting dispersion was placed on a Bruckner with a diameter of 30 cm. , in the presence of a paper filter under a vacuum of 10 mm Hg.

Filter the liquid twice on the same panel. The panels were then washed with 500ml of 820. Purify. The ratio of starch to water in the washing liquid is l:10.

Solubility measurements are performed on the filtered product to separate the product from water and Wash to remove flocculant. Disperse the product in water in a conventional laboratory pulper ( Dry concentration 0.2%, rotation speed 3000 rpm). sample after 4 hours and 8 minutes. Removed after filtration on Kron filter paper, the starch was added to the solution using the reagent "ANT". HRONE) J (0.2% Anthrone solution in 96% H2SO2) Measurement was carried out according to the above method on the filter panel of the fiber obtained according to the example. The determined solubility values are 1. It is less than 5%.

The morphological characteristics of the obtained fibers are shown in FIG.

Example 2 Microporous sintering constructed in the case of sintered metal tubes with pores having an average diameter of 100 μm The test according to Example 1 was repeated, changing only the characteristics of the filter. expressed in weight% Fibers with the following size distribution were obtained.

595 μm (28 mesh)%/0.3297 μm (40 mesh)%: 0 ．． 9149 μm (100 mesh)%: 6374 μm (200 mesh )%: 25.2 Above 200 mesh X100: 10. The result is the average diameter of the pores does not affect the proper method of fiber distribution, i.e. 100 to 200 mesh It shows that it is held in yu.

The solubility values obtained by the method of Example 1 were again less than 1.5% as in the previous case. Ru.

Example 3 (loaf, shaft side) The characteristics of the fiber obtained by the method of Example 1 can be transferred to another M&fiber mold manufacturing apparatus, especially an ishi-up machine. and compared with fibrets obtained by spinnerets.

Process conditions are the same as in Example 1.

The first fiber manufacturing device has eight holes with a diameter of 1 mm and an ejector shaft arranged in a groove. It consists of an ejector fitted with a starch inlet having an inclination of 45°. Ru. The speed of FL collector (ammonium sulfate) on the thin 101 side is 3! m/s to equal, and the withdrawal ratio (ratio between the maximum velocity of sulfate and that of starch leaving the hole) ) is equal to 47.

The second fiber manufacturing device is a spinning machine equipped with 113 holes with a diameter of 0.5 mm. Consists of a cap. This spinneret has a circulation duct separated from the outer surface of the spinneret. and annular crown, and the inner wall of the circulation duct is a flocculant, sulfuric acid. Supply Monium. Rate of ammonium sulfate and rate of starch raw material coming out of the hole are parallel. At the hole exit, the starch raw material comes into contact with the flocculant. then formed The suspended liquid is passed through a tapered nozzle (convergent) where highly turbulent flow completes the aggregation. (with a minimum diameter of 4 mm, corresponding to 30 m/s).

Table 1 reports a comparison of fiber distribution for various products and, as noted, There is a high percentage of fine particles (80%) for the Reduced when passed through a cap or tubular object. The distribution curves of these two types of fibers The fiber manufacturing equipment is different. That is, for tubular objects it is very narrow (90% (100 to 200 mesh molecules), wider range for spinnerets.

This size distribution depends on the particle shape (e.g. fibers with a significant shape ratio for tubular objects). Similarly, the spinneret has a high film content and is curled. , and the preferred method) are two types in papermaking together with cellulose fibers. in response to different behavior of the products. At this time, tubular fiber manufacturing equipment was installed in the laboratory. does not cause any problems in sheet manufacturing (forming and dry storage); Surface defects starting from a certain percentage when using the product from the spinneret It has been demonstrated that a sheet with a tendency to harden on the sheet forming plate is obtained. Confirmed experimentally.

Table 2 shows that after cellulose dispersion, Rapid-Keoth en) starch paste held on a sheet of paper produced in the laboratory using a device (at ambient temperature at 3000 rpm for 2 hours in the pulper) Starch raw material paste (10% of the latter)). As stated, the highest retention rate was obtained from tubular fibers. This is the case for products from manufacturing equipment.

Finally, Table 3 shows the scrubbing after flocculation and washing until ammonium sulfate is removed with tJF. Two types of filtering from slurry (slurry concentration and aging time are equal) The foreign matter shows twice the productivity of spinning 1'' gold.

Yet another feature of the invention is a solubility of less than 2% and viewer-machine concentration. After being classified using a Bauer-λ1cNe1.t device, 90% of the Provides the feature of having dimensions ranging from 00 to 200 meshes. This is starch fiber obtained by the above method.

Table 1 SRC distribution using various fiber manufacturing equipment

Claims (14)

[Claims] 1. Extrusion of dispersions or aqueous solutions in streams of starch feedstock in brine flocculants 1. A method for producing a fibrous starch raw material by: ■ pressing of a starch raw material surrounding a microporous tubular wall; A ring-wound part concentrically with the micropore wall in such a way as to obtain a flux. extruding the dispersion or aqueous solution through a microporous tubular wall indoors; and ■ Push by feeding a flow of flocculant into an annular chamber parallel to the extrusion surface. Operation to aggregate the performance A method characterized by: 2. The pore walls have an average diameter of at least 10 to 500 microns and Claim No. 2 providing a part with extruded surface holes of 0.05 holes/mm2 The method described in Section 1. 3. The extrusion through the hole on the micropore wall is carried out with an opening of 10 to 500 microns. from the narrow inlet section having a size of 10 to 100 mm larger than the narrow section. For larger outlets with opening size and 100 to 1000 drawers 3. The method according to claim 2, which is carried out using a ratio. 4. Extrusion through the hole on the micropore wall from the large inlet part for 10 to 50 minutes. a narrow exit section with an opening of 0 microns and smaller than the opening of the larger section; 3. The method of claim 2, wherein the method is carried out at a withdrawal ratio of 1 to 150 minutes per minute. 5. A claim in which the starch raw material is left in the annular chamber for a period of 5 to 15 milliseconds. 4. The method according to any one of 1 to 4. 6. Fiber production equipment, especially equipment for producing starch fibers by extrusion of a flocculant stream But. - a first inlet means (16, 31) for supplying a flux of starch raw material; a tubular member (14) having; - a supply chamber (21, 32) for starch raw material connected to said first inlet means; - starch; an annular outlet chamber (23, 34) for the raw material - coaxially with said outlet chamber (23, 34); said outlet located and inserted between the tubular member and the supply chamber (21, 32); The tubular member is made by extruding needles of various powder raw materials through the micropore wall in the chamber. A tubular element (2) with pore walls applied to form an envelope around the 2,33), - a second inlet hand connecting the outlet chamber for supplying the agglomerate flow; steps (16, 36) and - comprising evacuation means (17, 30) arranged downstream from the annular exit chamber; Fiber manufacturing equipment. 7. Said tubular element (22, 33) with a porous wall of 10 to 500 microns The claim is made of a sintered metal having pores having a size and shape of Fiber manufacturing apparatus according to scope 6. 8. Said tubular element (22, 33) with a porous wall of 10 to 500 microns a plurality of radial through holes having at least one narrow portion having dimensions and shape of ( 2425) Claim 6, characterized in that it is a cylindrical element with a hole-like wall. The fiber manufacturing apparatus described. 9. The holes provide an area on the extruded surface of 4 to 0.05 holes/mm2. The device according to claim 7 or 8. 10. Said annular outlet chamber (23) for starch raw material is coaxial with said supply chamber (21). 9. A device as claimed in claim 8, in which: 11. Provided that the radial holes have an opening size of 10 to 500 microns. Larger than the opening of the part (24) connecting with the room (21) and the above part (24) Claim 10 comprising a part (25) connecting with an exit chamber having a large size. The device described. 12. The annular outlet chamber (34) is coaxial with and exposed to the supply chamber (32). 9. The device of claim 8 in a radial interior. 13. an outlet in which the radial holes have an opening size of 10 to 500 microns; Larger than the opening of the part (24) connecting with the room (34) and the above part (24) Claim 1 comprising a supply chamber (32) having an opening of a large size and a connecting part. 2. The device according to 2. 14. Solubility and and 90% fiber or have dimensions in the range of 100 to 200 mesh. Starch fiber produced by the method according to claims 1 to 5.