JPS63141568A - Dehydrating and de-fatting treatment of solid material - Google Patents

Abstract

PURPOSE:To improve yield of raw material, to reduce drying energy cost extremely and to make it possible to de-fat and to dehydrate a solid material, by pressing the solid material in a steam atmosphere. CONSTITUTION:In pressing a solid material such as fish meal raw material, etc., heated in a certain degree or heat-treated by a screw pressing machine, centrifugal separator, etc., and extracting contained liquid substances such as water content, fat content, etc., pressing is carried out in a steam atmosphere at 80-90 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for compressing and extracting liquid substances such as water and fat contained in solid substances. More specifically, the present invention relates to improvements in the compression extraction method used when dehydrating and defatting fish meal raw materials or defatting edible or industrial fats from processed food products such as corn, dandelions, and soybeans. . In addition, in this specification, the solid substance mainly means the raw material for fish meal, but it also includes corn, meatballs,
This includes foods such as soybeans, processed products thereof, and all solid materials that are subjected to similar squeeze extraction methods.

(Conventional method) The manufacturing process for producing food materials and feed (fish meal) from raw fish and processed fish product residues (inedible parts) usually consists of boiling raw raw materials in one field and then continuously pressing them. It requires a process to separate water and fish oil, and is then dried and crushed to form a powdered product. The squeezing, dehydration and defatting process of the boiled beans in the production of fishmeal is to separate solids from liquid, and a screw press is generally used to carry out efficient continuous dehydration.

Regarding the compression itself, the pressure and pressurization time are important issues, and rapid application of pressure will suppress the movement of moisture from the center to the periphery, so a method of gradually increasing the pressure and compressing over time is recommended. It is taken.

Therefore, for example, in a conventional screw press machine, a conical screw @ 101 whose diameter is gradually expanded from the raw material population 102 toward the outlet 103 is adopted, and the volume 105 created between the screw shaft 101 and the casing 104 is transferred to the outlet 10.
It is gradually narrowed toward 3, and the compression force is gradually increased to advance the compression. The casing 104 is made of a perforated plate, and has a structure in which squeezed juice passes through a through hole 106, collects in a juice pan 107 at the bottom, and is discharged from an outlet. The basic purpose of pressing in the production of fitschmeal is
This is the separation of components that inhibit product storage, such as moisture and fat, from the solids, and can also be thought of as a preliminary drying operation. Therefore, in the pressing/dewatering process, the dewatering efficiency determines the load conditions in the next drying process, and influences the required energy amount, processing time, unit processing amount, etc.

In addition, in the case of compression for the purpose of degreasing, the deoiling efficiency influences the raw material yield and ultimately the product cost.

Furthermore, the residual crude fat contained in the solid content after dehydration and drying and its value are extremely important issues for the quality standards of the final product. As described above, the dehydration/degreasing process plays an important role in the overall process, and needs to be performed more efficiently in order to improve quality, productivity, cost, etc.

Of course, this is true not only for the production of fishmeal, but also for other food processing, defatting of edible oils from corn or palm, or any other production process that requires similar pressing treatments.

By the way, the raw material supplied to the above-mentioned screw press machine after the boiling process is cooled by natural heat radiation while passing through the separator and being sent on the screw conveyor, but the temperature is still high <80 to 90 degrees Celsius. conditions suitable for dehydration and degreasing.

On the other hand, the compression time with a screw press, that is, the time for the raw material to pass through the screw press, varies depending on the type of screw and processing capacity, but heat is released even during compression, so the material is discharged as a press cake. In many cases, the temperature drops significantly to 50" to 60℃, which reduces press efficiency. Conventionally, the inside of the screw is filled with steam to heat the screw and indirectly heat the raw material from inside. There are also presses that do this.

Further, in order to improve press efficiency and improve quality, the press process may be performed in two stages. This is a method in which the press cake that has been completed in one stage is warmed, poured with liquid juice, and then squeezed again using a press machine.The liquid juice added during the pressing process acts as a priming water, making the press considerably more efficient. .

(Problems to be Solved by the Invention) However, in the case of the former method of indirect heating from inside the screw, high heating temperatures may cause quality deterioration such as burning of the raw material. Moreover, the temperature drop during compression occurs from the outside exposed to the outside air, and indirect heating from inside the screw cannot be said to be effective. In addition, in the case of the latter two-time pressing, there are drawbacks such as two presses being required and a long pressing time.

Therefore, an object of the present invention is to provide an efficient degreasing and dehydration treatment method. More specifically, the present invention includes:
The purpose is to provide a degreasing and dehydration treatment method that is more efficient than conventional methods without increasing the system scale.

(Means for Solving the Problems) In order to achieve the above object quickly, the degreasing and dehydration treatment method of the present invention involves squeezing solid matter in a steam atmosphere.

The squeezing process is basically separation of solid content and liquid, but the liquid is mixed with water and oil and fat. Moisture contains components that are soluble in hot water, and the conditions for its outflow are thought to be related to temperature. Regarding fats and oils, the melting point of the fatty acid that forms the bottom of the fat varies depending on the number of carbon atoms; the higher the number of carbon atoms, the higher the melting point. As shown in Figure 2, the maximum temperature for common food ingredients is around 85°C.

Furthermore, as shown in Figure 3, the viscosity and specific gravity of fish oil also show large changes in relation to temperature. In order for the fats and oils to easily flow out of the raw material, it is desirable that the raw material should be melted from a solid state to a liquid state, and it is advantageous for the viscosity to be low and the specific gravity to be light. It can be understood that the higher the value, the more effective it is. If the fatty acid at the @ point had started to solidify due to the temperature drop, it would be difficult for it to liquefy and flow out. These physical properties of fish fats and oils indicate that it is desirable to maintain the temperature of the entire raw material at around 85° to 90° C. during the degreasing and dehydration steps from the start of the pressing to the end.

Furthermore, by adding a small amount of water, which acts as a priming element, during the stage of compression, liquid outflow becomes easier.

Direct heating with live steam has a humidifying element at first glance, but the temperature of the raw material at the beginning of compression is almost the same as the heating temperature, and if there is no temperature drop, no raw material will be consumed for heating the raw material. on the other hand,
Heat radiation from the screw press body is consumed, but this can be minimized by keeping the outside of the body warm. Although the condensed water from the heat-consuming steam mixes into the juice, the amount is small and the benefit of increasing the press efficiency of the squeezing process is far greater.

From the start to the end of compression in the screw press machine, steam at a temperature of about 90°C is stably supplied from the outside of the casing to keep the raw material temperature at around 90°C, and the raw material is surrounded by a steam atmosphere during compression. As a result, the fat content in the raw material remains molten, and subsequent degreasing by pressing becomes easy, making it possible to achieve a more efficient pressing effect.

(Example) Hereinafter, the method of the present invention will be explained in detail based on the experimental example shown in the drawings.

FIG. 1 schematically shows a screw press machine as an example of a device for carrying out the method of the present invention. This screw press machine consists of a screw 1, a compression body (hereinafter referred to as a casing) 2 made of a perforated plate, and a cover 3 that covers the casing 2 and makes it gas-solid. On the other hand, the press cake is discharged from the downstream outlet 4.

The steam is supplied to the space 5 provided between the casing 2 and the cover 3 and is filled with nucleons, thereby penetrating into the solid material/fish meal raw material being squeezed. The steam is supplied to the raw material population 6 in the space 5.
It is carried out from the steam injection pipe (sparsi vibe) 7 installed between the outlet 4 and the outlet 4. After the steam is reduced to an extremely low pressure by the pressure reducing valve 12, it further passes through the temperature control valve 13 to be at a very low pressure, and the amount of steam is controlled to produce a predetermined temperature. Incidentally, a steam temperature of less than 100° C. can be easily produced by known pressure manipulation even under atmospheric pressure.

In addition, the steam is subjected to steam and water separation in a steam and water separator 11,
Prevent condensed water in piping from blowing out during steam injection. Usually, the supervibe 7 is a pipe with small holes drilled at regular intervals on the surface.

In addition, in this embodiment, the outside of the casing 2 is surrounded by a cover 3 to form a space 5, and a steam atmosphere is created within the space to prevent the raw materials and solids between the screw 1 and the casing 2. Although the steam is provided so as to penetrate between the casing 2 and the casing 2, the steam may be directly injected into the casing 2.

In this embodiment, the space 5 formed between the casing 2 and the cover 3, which is directly heated by steam, is made of an S structure that completely surrounds the casing 2, but is not limited to this. If there is no opening 7 located at a higher level than the level required to secure the amount of steam necessary to satisfy a predetermined temperature, the steam will not be released to the outside or leak, so it is completely sealed. It is not necessary, and a structure that covers at least the upper half is sufficient. The raw material supply port 6 provided on the upstream side of the compression barrel opens upward, but during warm-up, a partition plate 14 is inserted to prevent leakage, and under normal operating conditions, the raw material itself There is no problem as it serves as a seal.

If a sensor/thermostat 8 is installed to control the temperature control valve 13 in order to maintain the steam atmosphere at a predetermined temperature, the steam will remain stationary in an extremely stable state. Since the air existing in the heating chamber from the beginning has a higher specific gravity than the steam, it moves to the lower part along with the steam supply and is naturally exhausted from the casing 2 having a large number of small holes.

The steam constituting the steam atmosphere is generally harmless, safe, and easily available water vapor, but is not limited to, but is not limited to, harmless vapor consisting of other components or water vapor containing a small amount of other harmless components. It can also be used.

Further, the temperature of the steam is usually adjusted to 80°C or higher and lower than 95°C, preferably 85°C to 90°C, and most preferably 85°C. Furthermore, depending on the raw material, the temperature may exceed 100°C.

Further, the screw 1 has a conical shaft whose diameter gradually increases from the raw material supply port 6 toward the outlet 4 and has scraper blades fixed thereto. In the figure, reference numeral 9 denotes a bottom plate, which is inclined to collect and easily drain the squeezed liquid. Further, reference numeral 15 is a gear.

The screw press constructed in this manner operates as follows.

Warm-up is performed until the inside of the screw press machine is heated by steam injected from the spasive vibrator 7 in the space 5 and introduced into the casing 2 until the set temperature is reached. When the inside of the casing 2 reaches the set temperature, the raw material is introduced from the supply port 6 and is sent to the outlet 4 side by the screw 1, and compression is started. At this time, if the raw material temperature is the same as the set temperature of the device, almost no heat consumption occurs. Heating in a steam atmosphere has a large heat retention factor, and excessive heating of raw materials (overtack) can cause quality deterioration and reduce the efficiency of the pressing and drying processes, so care must be taken to ensure that the temperature does not exceed a certain level. .

(Effects of the Invention) As is clear from the above description, the dehydration and degreasing method of the present invention is such that the solid material is squeezed in a steam atmosphere, so cooling of the solid material due to heat radiation can be prevented. Dehydration and degreasing efficiency can be improved. This pressing in a steam atmosphere may appear to have a humidifying element and is full of contradictions, but it also performs an important action that promotes dehydration and degreasing. Even if moisture were to adhere to the press cake due to direct steam contact, the temperature would be the same as the ambient temperature, and it would be removed by rapid self-evaporation when it exits the press and enters the dryer.

Naturally, the pressure inside the raw material is high during squeezing, and moisture does not penetrate. Rather, the steam filling the outside acts as a priming water equalizer and helps extraction. Therefore, the pressing efficiency is increased, the dewatering rate is improved, and the drying load after the pressing process is significantly reduced.

On the other hand, improved squeezing efficiency means significantly less crude fat remaining in the final product, and at the same time an increase in crude protein.

It has the effect of improving product shelf life, color, and ingredients, improving quality, productivity, and reducing costs. Specifically, as shown in Table 1, the dehydration effect is improved by about 2 to 3%. This improvement in the dewatering rate can only be achieved by passing the material through one more stage of the same type of press. Furthermore, the degreasing effect is improved by about 0.6%. This dramatically improves product quality and cost.

In addition, the experiment in Table 1 was conducted with a processing capacity of 1,000ffg/Hr,
In a screw press machine with a screw size of 470φ x 3,000s, raw fish 1,000 was preheated and kneaded with a press time of 20 to 40 minutes.
3 was pressed for 1 hour at a steaming temperature of 85° C., and samples were taken three times after 15 minutes, 30 minutes, and 45 minutes, and each sample was analyzed. Analysis was conducted using the conventional method and the method of the present invention for press cake and press water, respectively, and the average values were compared.

In this way, according to the method of the present invention, it is possible to improve the yield of raw materials and significantly reduce drying energy costs.

(Kite Chitoko et al.)

[Brief explanation of the drawing]

FIG. 1 is a schematic structural diagram of a screw press machine showing an example of an apparatus for carrying out the dehydration/degreasing method of the present invention.
is a central vertical cross-sectional view, and (B) is a cross-sectional view taken along the line B-B. FIG. 2 is a graph showing the relationship between the melting points of linear saturated fatty acids and their methyl esters, and FIG. 3 is a graph showing the viscosity and specificity of oil and pressed liquid in relation to temperature changes. FIG. 4 is a central vertical sectional view showing the schematic structure of a conventional screw press machine. DESCRIPTION OF SYMBOLS 1...Screw, 2...Casing, 3...Cover, 5...Space part. Patent applicant Furnace Co., Ltd. Nis. Figure 2: Return figure Figure 3: Temperature (・C)

Claims (5)

[Claims] (1) Dehydration of solids characterized by squeezing the solids in a steam atmosphere in a deoiling/dehydration process in which liquid substances contained in solids that have been heated or heated to a certain degree are extracted under pressure.・Degreasing method. (2) The method for dehydrating and defatting a solid material according to claim 1, wherein the solid material is a fish meal raw material. (3) The method for dehydrating and degreasing a solid material according to claim 1 or 2, wherein the steam is steam at a temperature of 80 to 90°C. (4) The method for dewatering and degreasing a solid material according to any one of claims 1 to 3, wherein the pressing is performed using a screw press machine. (5) The method for dehydrating and defatting a solid material according to any one of claims 1 to 3, wherein the pressing is performed using a centrifuge.