JPH0611261A - Drying control method for agricultural/marine product - Google Patents

Abstract

PURPOSE:To dry agricultural/marine products with high moisture quickly without deteriorating the quality by controlling the operation of a moisture-discharge damper which is totally opened, or intermittently opened/closed and totally closed based under a condition setting in response to the drying characteristics, and by an automatic temperature ascending control for the drying hot air. CONSTITUTION:The drying processes are divided into four periods of a constant rate of drying period, lapse rate of drying forward period, lapse rate of drying latter period and equilibrium drying period, and in the constant rate of drying period, a drying hot air at a set temperature is one-way blown in a drying chamber 2 of which a moisture-discharge damper 14 is totally opened, and the moisture-discharge operation is promoted. In the lapse rate of drying forward period and lapse rate of drying latter period, a drying hot air which is automatically heated in order based on respective previously set equations is circulated in the drying chamber 2 of which the moisture- discharge damper 14 is intermittently made to give an alternate opening/closing motions depending on the absolute humidity of the drying chamber, and in the equilibrium drying period, a drying hot air with a specified temperature is circulated in the drying chamber 2 of which the moisture-discharge damper 14 is totally closed, to dry agricultural/marine products.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to dried gourd, shiitake mushrooms, vegetables,
The present invention relates to a method for controlling drying of agricultural and marine products, which can efficiently dry agricultural products such as straw and straw grass, or marine products such as kelp, seaweed, and fish without damaging the quality.

[0002]

2. Description of the Related Art Conventionally, agricultural products such as dried gourd, shiitake mushrooms, vegetables, straw, and straw grass, or marine products such as kelp, seaweed, and fish are placed in a drying chamber of a dryer equipped with a moisture-exhausting damper, a moisture-absorbing damper, and a hot air generator. After being stored, the agricultural and marine products were dried to a predetermined water content while adjusting the temperature and humidity in the drying chamber to match the appropriate drying conditions by the circulating hot dry air circulation function and the opening / closing adjustment function of the moisture removal damper and the moisture absorption damper. The method for controlling the drying of agricultural and marine products is generally used and well-known, without exemplifying it.

[0003]

By the way, in the conventional method for drying this type of agricultural and marine products, when the high moisture content material to be dried contained in the drying chamber is efficiently dried to a predetermined moisture content without damaging the quality. In order to adapt to the drying characteristics of the material to be dried, the drying hot air of a predetermined temperature is blown into the drying chamber, and the temperature and humidity inside the drying chamber are adjusted so that the proper conditions for drying are met. It was intended to promote the drying while appropriately adjusting the opening and closing by the manual operation and intuition of the worker.

However, when the opening / closing adjustment of the moisture exhaust damper and the moisture absorbent damper is performed by the manual operation or intuition of the worker as described above, the temperature and humidity in the drying chamber cannot be accurately maintained for the labor. . Therefore, there has been a problem that the cell membrane is destroyed or corroded by bacteria due to abrupt temperature change or humidity change in the drying chamber during the drying operation, resulting in deterioration of quality.

According to the present invention, the condition setting according to the drying characteristic of the material to be dried can be easily achieved by the automatic opening / closing control and the automatic temperature raising control of the exhaust damper, and the rapid temperature and humidity change in the drying chamber during the drying operation. It is an object of the present invention to provide a method for controlling the drying of agricultural and marine products in which high-quality dried products can be obtained in a short time while saving fuel consumption.

[0006]

In order to achieve the above object, in the method for drying agricultural and marine products of the present invention, from the start of drying to the end of drying, the constant rate drying period, the rate-decreasing drying period, and the rate-decreasing drying period are set. And the equilibrium drying period. In the constant rate drying period, dry hot air of a preset temperature is blown into the drying chamber with the moisture exhaust damper fully opened during the drying time to dry the material to be dried. During the first period of reduced-rate drying and the latter period of reduced-rate drying, the dry hot air that is automatically heated in sequence based on the preset calculation formulas during each drying period is used, and the moisture exhaust damper is intermittently operated by the absolute humidity of the drying chamber. In the equilibrium drying period, dry hot air at a predetermined temperature is used during the equilibrium drying period, and the moisture exhaust damper is fully closed. Circulate circulation to Were those dried while the eye.

In the equilibrium drying period, when the moisture content of the material to be dried is dried to 10% or less by the blown dry hot air, the moisture removal damper is controlled to open / close for a predetermined time by the operation of the timer to perform forced moisture removal. Is.

[0008]

[Operation] When you want to dry the harvested high-moisture raw kelp efficiently through the preset constant rate drying period, decreasing rate drying period, decreasing rate drying late period and equilibrium drying period without damaging the quality, first , High-moisture kelp is housed in the drying chamber, and then the hot air generator is operated under the condition that the exhaust damper and the moisture absorbing damper are fully opened, and the obtained dry hot air at the predetermined initial temperature (for example, 40 ° C) is obtained. A constant rate drying period (eg 2
(Time) Medium Drying Spray the kelp while blowing air in one direction. Since most of the heat for drying supplied to the drying chamber is used as latent heat of vaporization, the moisture covering the surface of the kelp is quickly evaporated, or the absorbed hot dry air is discharged outside the drying chamber. Performs work that gets damp.

[0009] Next, when the constant rate drying period has passed and the rate-decreasing drying early period and the rate-decreasing drying late period have come, the amount of heat supplied into the drying chamber is used as sensible heat for raising the material temperature of kelp, The mesophyll gradually becomes dry and fixed, and if the temperature and humidity in the drying chamber change rapidly during this period, the cell membrane is destroyed and the quality is likely to deteriorate due to bacterial corrosion. It must be dried while being subjected to temperature and humidity conditions.

Therefore, in the first period of the rate-decreasing drying and the latter period of the rate-decreasing drying, the temperature of the hot air and the absolute humidity of the drying chamber are detected by the temperature sensor and the absolute humidity sensor during the period, and the respective detection signals are detected by the temperature detection circuit and the absolute humidity. It is sent to the control unit through the humidity circuit, and in the first half of the rate-decreasing drying, a calculation formula that is built in the drying condition setting unit in advance, for example,

[Equation 1] The temperature of the numerical value obtained based on the above is sequentially added to the initial temperature, and the set temperature of the drying hot air is automatically increased in sequence as the drying time elapses. Built-in formulas, for example

[Equation 2] The temperature of the numerical value obtained on the basis of the above is sequentially added to dry the hot air while setting the temperature of the dry hot air sequentially and automatically as the drying time elapses. During 6 hours, or during the drying time in the latter part of the reduced rate drying, for example, 4 hours, the intake damper and the intake damper are intermittently operated so that they are opened for 6 seconds and closed for 3 minutes based on the signal from the damper control circuit, and the intake air amount and exhaust moisture are removed. The humidity is controlled so that the absolute temperature becomes 50 gr / m ² while preventing a rapid change in the amount. Therefore, the dry hot air of the set temperature and the absolute humidity, which are suitable drying conditions, are obtained in the first period of the rate-reduced drying and the latter period of the rate-reduced drying, so that the kelp is dried rapidly without damaging the quality.

[0012] When the drying is in the equilibrium drying phase from the latter part of the rate-decreasing drying, the kelp has reached a substantially equilibrium water content, but some moisture remains in the core of the trunk and the thick wall, so the finishing temperature ( For example, if finish drying is performed while circulating dry circulation of dry hot air of 60 ° C. in a drying chamber in which the exhaust moisture damper and the intake damper are fully closed during the drying time (for example, 4 hours),
The kelp is dried to a predetermined water content (for example, 12%).

When it is desired to dry the kelp to a water content of 10% or less, hot dry air having a finishing temperature (for example, 60 ° C.) is blown into the drying chamber, and the moisture removal damper and the intake damper are used for 3 minutes during the drying time. If the forced dehumidification work is performed by repeatedly controlling the moisture damper and the intake damper to be closed for 1 hour, the kelp is dried so that the moisture content is 10% or less.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of an agricultural and marine product drying apparatus for carrying out the method according to the present invention will be described with reference to the drawings. In FIG. 1 and FIG. 2, reference numeral 1 denotes a drying device capable of efficiently drying agricultural products such as dried gourd, shiitake mushrooms, vegetables, straw, and straw grass, or marine products such as kelp, seaweed, and fish without damaging the quality. The drying device 1 is provided with a drying chamber 2 that can appropriately store agricultural and marine products and a ventilation chamber 3 that can blow dry hot air of a predetermined temperature in the drying chamber 2 so that they can communicate with each other at the upper and lower portions. It is composed. A heat exchange type hot air generator 4 including a burner 5 and a blower 6 is housed and installed in the air blowing chamber 3, and hot air blowing of the hot air generator 4 at the bottom of the drying chamber 2 is provided. A temperature sensor 8 for detecting the temperature in the drying chamber 2 and an absolute humidity sensor 9 for detecting the absolute humidity in the drying chamber 2 are arranged in the drying chamber 2 near the outlet 7. Reference numeral 10 denotes an intake window opened on one side of the drying chamber 2 near the upper side of the blower chamber 3, and 11
Is a moisture exhaust window that is open at one side of the upper part of the drying chamber 2 facing the intake window 10. The intake window 10 and the moisture exhaust window 11 are simultaneously opened and closed by the rotation operation of the damper drive motor 21. Intake damper 13 and dehumidification damper 14
Is rotatably mounted to circulate the heated dry hot air in the drying chamber 2 or to partially inhale and partially exhaust it.

FIG. 2 shows a control block circuit 15 for carrying out the method for drying agricultural and marine products. In the control block circuit 15, 16 is a control unit, to which the temperature sensor 8 is connected via a temperature detection circuit 17 and the humidity sensor 9 is connected via an absolute humidity detection circuit 18, respectively. There is. Reference numeral 19 is a drying period setting timer, and 20 is a drying condition setting unit.
The drying period setting timer 19 is a constant-rate drying period (for example, 2 hours), a reduced-rate drying early period (for example, 6 hours), a reduced-rate drying late period (for example, 4 hours), and an equilibrium drying period (for example, 4 hours). ) Of the 4th period. The drying condition setting unit 20, for example,

[Equation 3] and

[Equation 4] The temperature data obtained by sequentially adding the temperatures of the numerical values obtained on the basis of the calculation formula is sent to the control unit 16.
Reference numeral 21 denotes a damper drive motor, and the damper drive motor 21 drives the intake damper 13 and the exhaust moisture damper 14 to open and close. The damper drive motor 21 is connected to the control unit 16 via a damper control circuit 22. The burner 5 is connected to a control unit 16 via a burner control circuit 23.

In the constant rate drying period, the control block circuit 15 fully opens the intake damper 13 and the exhaust moisture damper 14, and controls the burner 5 so as to maintain the temperature set by the drying condition setting section 20, thereby drying. Can be continued. Then
During the first period of the rate-decreasing drying and the latter period of the rate-decreasing drying, the burner 5, the intake damper 13, and the exhaust gas are discharged so that the temperature and the absolute humidity detected by the temperature sensor 8 and the humidity sensor 9 maintain the conditions set by the drying condition setting unit 20. The opening of the wet damper 14 is controlled (for example, opened for 6 seconds and closed for 3 minutes) and dried. Next, in the equilibrium drying period, the burner 5 is controlled so as to maintain the dry hot air having the finishing temperature (for example, 60 ° C.) set by the drying condition setting unit 20, and the intake damper 13 and the exhaust damper 14 are fully closed. The damper drive motor 21 is controlled so that When the material to be dried is dried to a water content of 10% or less, the intake damper 13 and the exhaust moisture damper 14 are connected to the damper drive motor 2
1, the forced dehumidification work may be performed by repeatedly controlling the opening for 3 minutes and the closing for 1 hour.

[0016]

EFFECTS OF THE INVENTION Since the present invention uses the drying control method described above, the following effects can be obtained. The period from the start of drying to the end of drying is divided into a constant rate drying period, a rate-decreasing drying period, a rate-decreasing drying period and an equilibrium drying period.
Moreover, in the constant rate drying period, hot dry air of a preset temperature is blown into the drying chamber with the moisture exhaust damper fully opened during the drying time to quickly remove high moisture contained in the material to be dried. Drying control is performed so as to evaporate and then, in the reduced rate drying early period and the reduced rate drying late period, dry hot air that is automatically heated in sequence based on the respective calculation formulas set in advance during each drying period is dried. The moisture exhaust damper is intermittently opened and closed depending on the absolute humidity of the room to circulate and circulate it in the drying room where the humidity inside the drying room is controlled to gradually increase the temperature of the material to be dried and gradually dry and fix it from the thin meat layer. , Good drying while preventing temperature changes in the drying chamber and cell membrane destruction or bacterial corrosion caused by rapid temperature changes, and during the final equilibrium drying period, during the drying period It is possible to efficiently dry the trunk of the material to be dried and the core of the thick wall while circulating the hot dry air at a constant temperature in the drying chamber with the exhaust moisture damper fully closed. In addition to being able to efficiently perform high quality dry matter while shortening the drying time and saving fuel consumption, it is also possible to open and close the moisture removal damper for a predetermined time by operating the timer in the equilibrium drying period. If controlled, the water content of the material to be dried can be dried to 10% or less.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of a drying device for carrying out a drying control method of the present invention.

2 is a drying control block circuit diagram for carrying out the drying control method of the present invention. FIG.

FIG. 3 is a graph showing the relationship between drying time and temperature setting.

[Explanation of symbols]

 1 Drying Device 2 Drying Room 3 Air Supply Room 4 Hot Air Generator 5 Burner 8 Temperature Sensor 9 Humidity Sensor 13 Intake Damper 14 Dehumidification Damper 15 Control Block Circuit 16 Control Unit 17 Temperature Detection Circuit 18 Absolute Humidity Detection Circuit 19 Drying Period Setting Timer 20 Drying condition setting circuit 21 Damper drive motor 22 Damper control circuit

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[Procedure amendment]

[Submission date] October 26, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0002

[Correction method] Change

[Correction content]

[0002]

Conventionally, gourd shavings, mushrooms, vegetables, straw, agricultural products such as rush or kelp, seaweed, seafood Moisture removal damper such as fish, drying chamber of the drying apparatus equipped with the air intake damper and a hot air generator, etc., after storing the dry finishing a predetermined moisture while adjusting to meet the drying proper conditions the temperature and humidity in the drying chamber by opening and closing regulating effect of the circulating flow action and moisture removal dampers and inspiratory damper the agricultural marine dry hot air The method for controlling the drying of fermented agricultural and marine products is generally used and well known, without exemplifying it.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

[0003]

By the way, in the conventional method for drying this type of agricultural and marine products, when the high moisture content material to be dried contained in the drying chamber is efficiently dried to a predetermined moisture content without damaging the quality. in is to adapt the drying characteristics of the material to be dried, with the dried hot air pre-determined temperature is blown to the drying chamber, moisture removal dampers and air intake as dry properly condition is satisfied the temperature and humidity of the drying chamber The dampers were opened and closed appropriately by the operator's manual operation and intuition to promote the drying.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

However, when the opening and closing regulation of Moisture removal dampers and air intake damper as described above was carried out by a manual operation and intuition of the operator is able to accurately maintain the temperature and humidity of the drying chamber to divide the labor Can not. Therefore, there has been a problem that the cell membrane is destroyed or corroded by bacteria due to abrupt temperature change or humidity change in the drying chamber during the drying operation, resulting in deterioration of quality.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

[0008]

[Operation] When you want to dry the harvested high-moisture raw kelp efficiently through the preset constant rate drying period, decreasing rate drying period, decreasing rate drying late period and equilibrium drying period without damaging the quality, first , the drying chamber containing the high moisture kelp, then operating the hot-air generator under a state of fully open moisture removal dampers and air intake damper, drying the resulting initial predetermined temperature (e.g. 40 ° C.) Hot air is dried at a constant rate (for example, 2
(Time) Medium Drying Spray the kelp while blowing air in one direction. Since most of the heat for drying supplied to the drying chamber is used as latent heat of vaporization, the moisture covering the surface of the kelp is quickly evaporated, or the absorbed hot dry air is discharged outside the drying chamber. Performs work that gets damp.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

Therefore, in the first period of the rate-decreasing drying and the latter period of the rate-decreasing drying, the temperature of the hot air and the absolute humidity of the drying chamber are detected by the temperature sensor and the absolute humidity sensor during the period, and the respective detection signals are detected by the temperature detection circuit and the absolute humidity. sent to the control unit via the humidity circuit, in the falling rate drying year, formulas that are built into the pre-dried condition setting portion, for example, the a (° C.), the initial temperature setting temperature B
(° C), finishing temperature is C (° C), drying time in the first period of reduced rate drying
Is D (hour), and the elapsed dry time in the previous period of reduced rate drying is E (hour)
Interval), the temperature of the numerical value obtained based on A = B + [{(C−B) / 2} / D] × E is sequentially added to the initial temperature, and dry hot air is added as the drying time elapses. In addition to automatically increasing the set temperature of, in the latter half of the rate-decreasing drying, a calculation formula previously incorporated in the drying condition setting unit, for example,
Furthermore, the drying time in the latter part of the rate-decreasing drying is F (hour)
Assuming that the drying elapsed time in the latter half is G (hour), A = {(C + B) / 2} + [{(C−B) / 2} / F]
The temperature of the numerical value obtained on the basis of × G is sequentially added, and as the drying time elapses, the temperature of the drying hot air is automatically raised while drying, while the absolute humidity in the drying chamber is reduced rate Open the exhaust damper and the intake damper for 6 seconds on the basis of a signal from the damper control circuit, for example, for 6 hours, or for the drying time in the latter part of the reduced rate drying, for example, 4 hours, 3
Min closed and so as to intermittently operate allowed to intake air amount and Moisture removal amount absolute humidity while preventing a sudden change in, for example, 20 g
Humidify to r / m ³ . Therefore, the dry hot air of the set temperature and the absolute humidity, which are suitable drying conditions, are obtained in the first period of the rate-reduced drying and the latter period of the rate-reduced drying, so that the kelp is dried rapidly without damaging the quality.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction content]

When it is desired to dry the kelp to a water content of 10% or less, dry hot air having a finishing temperature (for example, 60 ° C.) is blown into the drying chamber and, for example , the moisture removal damper and the intake air are supplied for 3 minutes during the drying time. If the forced moisture removal work is carried out by repeatedly controlling the moisture damper and the intake damper to be opened for one hour, and drying the kelp, the drying will be promoted so that the moisture content will be 10% or less.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction content]

FIG. 2 shows a control block circuit 15 for carrying out the method for drying agricultural and marine products. In the control block circuit 15, 16 is a control unit, to which the temperature sensor 8 is connected via a temperature detection circuit 17 and the humidity sensor 9 is connected via an absolute humidity detection circuit 18, respectively. There is. Reference numeral 19 is a drying period setting timer, and 20 is a drying condition setting unit.
The drying period setting timer 19 is a constant-rate drying period (for example, 2 hours), a reduced-rate drying early period (for example, 6 hours), a reduced-rate drying late period (for example, 4 hours), and an equilibrium drying period (for example, 4 hours). ) Of the 4th period. The drying condition setting unit 20, for example, A = B + [{(C−B) / 2} / D] × E and A = {(C + B) / 2} + [{(C−B) / 2} / F ]
The temperature data obtained by sequentially adding the temperatures of the numerical values obtained based on the calculation formula of × G is sent to the control unit 16.
Reference numeral 21 denotes a damper drive motor, and the damper drive motor 21 drives the intake damper 13 and the exhaust moisture damper 14 to open and close. The damper drive motor 21 is connected to the control unit 16 via a damper control circuit 22. The burner 5 is connected to a control unit 16 via a burner control circuit 23.

[Procedure Amendment 8]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

Claims (2)

[Claims] 1. From the start of drying to the end of drying, a constant rate drying period, a decreasing rate drying early period, a decreasing rate drying late period and an equilibrium drying period
In the constant rate drying period, dry hot air of a preset temperature is blown into the drying chamber with the moisture exhaust damper fully open during the drying time to dry the material to be dried In the latter half of the rate-decreasing drying, the dry hot air that is automatically heated in sequence based on the respective preset calculation formulas during each drying period is used to intermittently repeat the opening and closing operation of the moisture exhaust damper by the absolute humidity of the drying chamber. In the equilibrium drying period, hot dry air with a predetermined temperature is circulated in the drying chamber with the exhaust moisture damper fully closed during the equilibrium drying period. A method for controlling the drying of agricultural and marine products characterized by being dried. 2. In the equilibrium drying period, when the moisture content of the material to be dried is dried to 10% or less by the dried hot air that has been blown, the moisture removal damper is controlled to open / close for a predetermined period of time to force moisture removal. The method for controlling drying of agricultural and marine products according to claim 1.