JP5545816B2 - Circulating grain dryer - Google Patents

Description

The present invention relates to a circulation type grain dryer that dries grains such as rice cakes and wheat, and particularly relates to reduction in fuel consumption and energy saving during drying operation.

2. Description of the Related Art Conventionally, a circulation type grain dryer has been known that aims to reduce the consumption of kerosene fuel of a burner that generates hot air when grains are dried (Patent Document 1). The one described in Patent Document 1 performs a pause operation (tempering operation) in which the burner and the like are completely stopped during the drying operation for an arbitrary time, and reduces the amount of kerosene that does not burn during the pause operation. It was a thing.

Japanese Patent Laid-Open No. 11-132657

The thing of the said patent document 1 has the effect of stopping a burner etc. during the said pause operation, and reducing fuel consumption . However, as the condition for deactivating operation, after the start of drying, grain moisture value is reduced to 20% or less, and is intended to perform only a low outside air temperature is most midnight morning time zone, grain moisture value At times other than the time until drying to 20% and the time zone when the outside air temperature is low, no means for reducing the fuel consumption was taken .
In view of the above problems, the present invention has as a technical problem to provide a circulation type grain dryer that further reduces energy consumption by reducing the consumption of kerosene fuel.

In order to solve the above problems, the circulation type grain dryer of the present invention,
A grain storage tank,
A drying section for drying the grain flowing down from the storage tank section by blowing hot air;
A discharge section for discharging grain in the drying section;
A recirculation section for returning to the reservoir tank grain discharged from the outlet portion via the upper transverse conveying means of the upper temperature disembarkation and the reservoir tank,
A grain moisture measuring unit for measuring grain moisture;
An operation control unit that controls drying operation and the like until the grain moisture value measured by the grain moisture measurement unit reaches a set moisture value, and controls operation switching such as hot air drying operation, air blowing operation, and tempering operation;
In the circulating grain dryer with
The operation control unit always calculates a predicted drying rate dV when the blowing operation is performed under the current outside air condition, and determines that drying of the grain proceeds when the predicted drying rate dV is equal to or greater than a predetermined value. Technical measures were taken to switch operation to operation.

The operation control unit determines whether the grain moisture value is larger than a predetermined value when the predicted drying rate dV is less than a predetermined value, and determines the drying rate when the grain moisture value is larger than a predetermined value. It is preferable to switch to a reduced hot air drying operation and to a tempering operation (pause operation) when the grain moisture value is smaller than a predetermined value. Thereby, the energy-saving effect of the reduction of the electric power consumption by the drive stop of an exhaust fan is also acquired by rest driving | operation (all stop).

The circulation type grain dryer of the present invention always calculates the predicted drying rate dV when the air blowing operation is performed under the current outside air conditions (temperature, humidity, etc.) after starting the drying operation, and the predicted drying rate dV is a predetermined value. In the above case, it was judged that the drying of the grain proceeded, and the operation was switched to the blowing operation by the outside air not performing the burner combustion. As a result, even if the outside air conditions such as outside temperature and outside humidity change, switching to the blowing operation is always performed while monitoring whether or not the outside air condition is such that drying proceeds, so the selection of the blowing operation・ Switching is accurate, energy consumption can be reduced by reducing the consumption of kerosene fuel , and quality is maintained without causing mold etc. in grains with high moisture content by ensuring the progress of grain drying. Safe drying. And since the circulation type grain dryer of this invention does not receive the time restriction | limiting at the time of operation switching like the conventional grain dryer, it further improves the energy-saving effect which reduces the consumption of kerosene fuel. Can do.

The front perspective view in the circulation type grain dryer of the present invention is shown. The rear perspective view in the circulation type grain dryer of the present invention is shown. The front longitudinal cross-sectional view in the circulation type grain dryer of this invention is shown. The block diagram in the operation control part of this invention is shown. The flowchart of the energy saving drying operation program in this invention is shown. The list of the calculation formulas related to the energy saving drying operation program of the present invention is shown. Calculation Example 1 related to the energy-saving drying operation program of the present invention is shown. Calculation Example 2 related to the energy-saving drying operation program of the present invention is shown. The graph showing the relationship between the predicted water removal amount W related to the energy-saving drying operation program of this invention and the blowing air water absorption possible amount E is shown.

Figure 1 is a front perspective view of a circulating type grain dryer 1 of the present invention, FIG. 2 is a rear perspective view of the upper same, FIG. 3 is a longitudinal sectional view seen from the front side of the upper same . Circulating type grain dryer 1, reservoir 2 for storing grain, the take-out portion 4 and eject the by ventilating dry air undergoing drying section 3 and the air to dry the cereal grains to the outside of the apparatus a heavy set to configure, further, the the take-out portion 4 connects grain recirculation means 5 for recirculating Installing issued cereal in the reservoir 2. The grain recirculation means 5 refers to the elevator 5a and the upper transport unit 5b. A grain dispersal device 5c facing the storage unit 2 is disposed at the conveyance end of the upper conveyance unit 5b. The storage part 2 is formed by being surrounded by a ceiling wall or a side wall. The drying unit 3 includes a hot wind tunnel 6 installed in the center of the machine body , drying chambers (grain flow passages) 7 , 7 that are horizontally installed on both sides of the hot wind drum 6 and are formed with perforated walls , and the drying chamber 7. The exhaust wind tunnels 8 and 8 are installed horizontally on the sides. A hot air generating means (burner) 9 is connected to one end opening of the hot air drum 6 so as to supply hot air. Hot air generated by the heat air generating means 9, Neppudo 6, a drying chamber 7, 7 and Haifudo 8, 8 and ventilation, suction exhaust fan 10 connected to the air discharge port of Haifudo 8, 8 The air is exhausted by the action . Incidentally, the side walls forming the body of the drying unit 3 are equipped with lid 3a for you include your grain.

The take-out unit 4 includes a rotary valve 11 horizontally installed at a central position where the lower ends of the left and right drying chambers 7 , 7 intersect, and a funnel-shaped collection of grains that is positioned below the rotary valve 11 and collects grains. It consists of boards (dashboards) 13 and 13 and a lower transport section 12 below the grain collection boards 13 and 13 . Then, the fed out from the rotary valve 11 grain is adapted to be transported out of the apparatus being AtsumariKoku to the lower transport section 12. In addition, the conveyance termination | terminus side of the said lower conveyance part 12 is connected with the conveyance start end side of the said elevator 5a, and the conveyed grain is conveyed by the said elevator 5a. A known grain moisture meter 15 is disposed on the side of the elevator 5a. Reference numeral 14 denotes an operation control unit that controls the operation of the circulation type grain dryer.

Next, a detailed description of the construction of the prior SL operation control unit 14. Figure 4 is a block diagram showing an example of the operation control unit 14. OPERATION control unit 14, together constitute a central unit (hereinafter referred to as "the CPU") 19, the CPU19 and input-output circuit (hereinafter referred to as "I / O") electrically connected respectively 20, write-only memory part 21 is constructed from (hereinafter "ROM" hereinafter) and a write-read combined storage section 22 (hereinafter referred to as "RAM") and. Before SL I / O20 drying operation buttons and Chokomi operation button, various operating operation buttons 23 consisting Chokomi amount setting dial and finishing moisture value setting dial and the like are electrically connected. This is driving operation button 23, conventional drying operation buttons or other blowing operation buttons, Ru Tei with an energy-saving drying operation mode button with the present invention. The addition the I / O20, the grain moisture meter 15 and the hot air generator 9, the elevators 5a and a rotary valve 11 the motors (not shown) power system driving circuit for driving the like 24, a drying operation conditions In addition to the input setting unit 18 for input setting, an outside air temperature sensor 16 and an outside air humidity sensor 17 described later are electrically connected. The operation control unit 14 also has a clock function.

The operation control unit 14 is provided with an outside air temperature sensor 16 and an outside air humidity sensor 17 at arbitrary locations such as in the vicinity of the operation control unit 14 , and these outside air temperature sensor 16 and outside air humidity sensor 17. As described above, a detection signal is sent to the operation control unit 14.

The ROM 21 of the operation control unit 14 stores an example of a so-called energy-saving drying operation program that is a characteristic configuration of the present invention (see the flowchart of FIG. 5) .

Action:
Next, the operation of the circulation type grain dryer 1 having the above configuration will be described. Before starting the energy saving drying operation of the present invention, the circulation type grain dryer 1 inputs and sets a dry finish moisture value, a grain tension amount, and the like from the input setting unit 18 and inputs other setting conditions. Set. Thereafter, when the energy saving drying operation mode button of the operation operation button 23 is pressed, execution of the energy saving drying operation program by the operation control unit 14 is started. In addition , cereal is already pasted.

Step 1, 2:
The energy saving drying operation mode button (driving operation button 23) is pressed to start execution of the energy saving drying operation program. When the execution of the energy saving drying operation program is started, first, the grain recirculation means 5, the rotary valve 11, the lower conveyance unit 12, etc., which are the circulation system of the circulation type grain dryer 1, are driven to start the operation.

Step 3:
Wherein the outside air temperature sensor 16 and the outdoor air humidity sensor 17 measures the outside air temperature and outdoor humidity read values.

Step 4:
Then, the outside air saturated water vapor pressure and the ambient air water vapor pressure based on the outdoor air temperature value and the outdoor air humidity value, for example, determined by calculation expression shown in FIG. 6 (a), then the external air saturated water vapor pressure and the ambient water the vapor pressure based on outside air absolute humidity C and the outdoor air saturated absolute humidity D is also determined. Then, it calculates a difference of the outer air absolute humidity C and the ambient air saturated absolute humidity D, and when blown dry (blast operation) in ambient conditions at that time, air blown water outside air 1kg is water available water absorption future The possible amount E is obtained. These calculations can also be obtained by the calculation formula shown in FIG.

Step 5:
Next, it is determined whether the tempering operation is currently in progress. In the judgment of Step 6 immediately after the start of the energy-saving drying operation program , in addition to the tempering operation (pause operation), the hot air drying operation (burner combustion and blowing) and the blowing operation by the outside air (fan drying: only blowing) are still executed. Since it is not done, the process proceeds to the next step 6. On the other hand, when the tempering operation is in progress, the routine proceeds to step 9.

Step 6:
The grain moisture meter 15 measures grain moisture and reads the value.

Steps 7 and 8:
It is determined whether or not the measured moisture value is the dry finish moisture value.If the measured moisture value is the dry finish moisture value, the drying is terminated, while if the dry finish moisture value is not reached, Proceed to the next step 9.

Step 9:
In this step, the predicted water removal amount W and the predicted dryness reduction rate dV at the time of air drying (air blowing operation) are obtained. The predicted water removal amount W is a predicted value of the amount of water to be removed per hour when air blowing and drying (air blowing operation) is performed under the outdoor air conditions at that time. As shown in FIG. 7, the predicted water removal amount W has a proportional correlation with the blast air water absorption amount E (calculated in step 4) obtained based on the current outside air condition. For this reason, the predicted water removal amount W may be appropriately determined by experimentally creating the relational expression (calculation formula) shown in FIG. 6A in relation to the blast air water absorption possible amount E. . At this time, in FIG. 6A, the coefficient in the calculation formula of the predicted water removal amount W is merely an example. Further, as shown in FIG. 7, the blowable air water absorption amount E varies depending on the grain moisture value (powder moisture) high and low, and is appropriately determined according to the amount of cereal filling. Since it also changes depending on the air volume Q, it is necessary to obtain the predicted water removal amount W taking these items into consideration.

On the other hand, the predicted drying rate dV is a predicted value of the drying rate that is dried per hour when blown and dried (fan operation) under the current outside air conditions. For example, as shown in Calculation Example 1 in FIG. 6B, the predicted dryness reduction rate dV is calculated by taking into consideration the predicted water removal amount W obtained based on the current outside air condition , for one hour. Subsequent estimated drought moisture (estimated grain moisture ) Y = 23.7% is obtained, and then by subtracting 23.7% from the measured moisture value of 24%, in the case of calculation example 1, the predicted drying rate dV is 0. .3% / h. In addition, the predicted dryness reduction rate dV can be similarly obtained for calculation example 2 in FIG.

Step 10:
In this step, it is determined whether or not the predicted dryness rate dV obtained in step 9 is equal to or higher than a predetermined dryness rate, and the degree of progress of the drying action in the case of air drying (air blowing operation) under the current outside air condition is determined. Predict and judge whether to blow and dry. When the predicted drying rate dV is, for example, 0.2% / h or more, it is predicted that the progress of the drying action is ensured under the current outside air condition even if the air blowing operation is performed, and thus the process proceeds to Step 11. To start air drying (air blowing operation). On the other hand, if the predicted drying rate dV is less than 0.2% / h, the process proceeds to step 12.

Step 11:
In this step, execution of blow drying (blow operation) is started. The air blowing operation is an operation of sucking outside air from the front side of the circulation type grain dryer 1 by the action of the exhaust fan 10 and causing the grain to flow through the drying chamber 7 without burning the burner 9. . For this reason, since the burner 9 is not driven during the air blowing operation, the kerosene fuel is not consumed, and energy-saving drying proceeds. At this time, since the predicted drying rate dV is 0.2% / h or more even if the air blowing operation is performed, the grain can be dried without causing mold or the like even if the grain has high moisture. It is possible to proceed with drying that is safe for grain quality.

Step 12:
In this step, it is determined whether or not the grain moisture value measured in step 6 is less than 18%. If the grain moisture value is lower than 18%, the process proceeds to step 13 and the tempering operation (stop operation) is performed. If the grain moisture value is higher than 18%, the routine proceeds to step 14 where hot air drying operation is performed.

Step 13:
In this step, tempering operation is performed. The tempering operation stops the driving of the grain recirculation means 5 and the rotary valve 11 which are the circulation system of the circulation type grain dryer 1, and also stops the driving of the exhaust fan 10, and the grain is stored in the storage unit 2. Is tempered. Since both the combustion of the burner 9 and the driving of the blower 10 are stopped by the tempering operation, an energy saving effect is achieved by reducing the amount of kerosene consumed and the amount of power used.

Step 14:
In this step, a hot air drying operation is performed. In the hot air drying operation, the burner 9 is driven to generate hot air having a relatively low temperature while suppressing the amount of burning of kerosene, etc., and is passed through the grains flowing down the drying chamber 7 at a low speed (small drying rate is reduced). The operation is to dry the grain. Thereby, safe drying can be promoted by hot air generation by low fuel consumption with reduced combustion amount and the like so as not to cause mold or the like in dry grains with high moisture content.

  With the above steps, the energy-saving drying operation program of the present invention (FIG. 5) is for the purpose of obtaining energy-saving effect (reducing consumption of kerosene fuel) without performing burner combustion as much as possible while monitoring the current outside air conditions. The operation is switched to one of blow drying (step 11), tempering operation (all stop operation, step 13) and hot air drying (low speed / slow, step 14). Thereafter, returning to Step 3, the same determination and processing as described above are repeated until the grain moisture value becomes the dry finish moisture value. Thereby, even when the outside air temperature and the outside air conditions change, the predicted drying rate dV in the case of the air drying is obtained at any time, and whether to perform the air drying or other operation is accurately determined. Then driving is performed. For this reason, while always monitoring whether or not the outside air conditions are such that the drying proceeds, the switching to the blowing operation is performed accurately, the consumption of kerosene fuel is reduced, energy saving operation is performed, and the quality of the dried grain Safe drying without lowering is possible.

  According to the present invention, the circulation grain dryer according to the present invention switches to the air blowing operation while always judging whether or not the drying action proceeds when air drying is performed based on the current outside air condition. As a result, safe drying can be performed without adversely affecting the quality of high moisture grains, and energy-saving drying with reduced consumption of kerosene fuel can be performed.

DESCRIPTION OF SYMBOLS 1 Circulating grain dryer 2 Storage part 3 Drying part 3a Opening / closing lid 4 Extraction part 5 Grain recirculation means 5a Elevator 5b Upper conveyance part 5c Grain disperser 6 Hot air drum 7 Drying chamber 8 Exhaust air drum 9 Hot air generating means (burner)
DESCRIPTION OF SYMBOLS 10 Air exhaust machine 11 Rotary valve 12 Lower conveyance part 13 Grain collection board 14 Operation control part 15 Grain moisture meter 16 Outside temperature sensor 17 Outside air humidity sensor 18 Input setting part 19 Central processing part (CPU)
20 I / O circuit (I / O)
21 Write-only memory (ROM)
22 Write / read memory unit (RAM)
23 Operation button 24 Power system drive circuit

Claims (2)

A grain storage tank,
A drying section for drying the grain flowing down from the storage tank section by blowing hot air;
A discharge section for discharging grain in the drying section;
A recirculation section for returning to the reservoir tank grain discharged from the outlet portion via the upper transverse conveying means of the upper temperature disembarkation and the reservoir tank,
A grain moisture measuring unit for measuring grain moisture;
An operation control unit that controls the drying operation and the like until the grain moisture value measured by the grain moisture measurement unit reaches a set moisture value, and that controls operation switching between hot air drying operation, air blowing operation, and tempering operation,
In the circulating grain dryer with
The operation control unit always calculates a predicted drying rate dV when the blowing operation is performed under the current outside air condition, and determines that drying of the grain proceeds when the predicted drying rate dV is equal to or greater than a predetermined value. Circulation type grain dryer characterized by switching operation to operation. The operation control unit determines whether or not the grain moisture value is larger than a predetermined value when the predicted drying rate dV is less than a predetermined value, and decreases the drying rate when the grain moisture value is larger than a predetermined value. The circulating grain dryer according to claim 1 , wherein the circulation grain dryer is switched to a hot air drying operation and switched to a tempering operation when the grain moisture value is smaller than a predetermined value.

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