JPH051885A - Dehumidifying drier - Google Patents

Abstract

PURPOSE:To restrict the releasing of much amount of dust to the outside of the title drier and prevent the contamination of atmosphere while avoiding the deterioration of drying efficiency of grains. CONSTITUTION:A dehumidifying drier is provided with a ventilating means B, ventilating dehumidifying air into a drying unit 1, and an air discharging means C, discharging air in the drying unit 1. The air discharging means C is controlled so that the discharging amount of air of the same becomes smaller than the ventilating amount of the ventilating means B by a predetermined amount.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dehumidifying dryer, and more particularly, to a blowing means for blowing dehumidifying air to a drying section for containing grains for drying, and an exhaust air for discharging the air in the drying section. And a dehumidifying dryer having a means.

[0002]

2. Description of the Related Art In a conventional dehumidifying dryer, a drying operation is carried out without considering whether or not the mutual relationship between the amount of air blown by an air blower and the amount of air exhausted by an air exhauster is appropriate.

[0003]

The grain in the drying section of the conventional dehumidifying dryer is usually dried while being switched between a circulating state in which the circulating movement is carried out in the drying section and a stationary state in which the circulating movement is stopped. However, when the blown air amount is smaller than the exhausted air amount in the stationary state, the pressure inside the drying section becomes low, so that the outside air enters the drying section through the gap of the casing. When such invasion of external air occurs, there is a problem that the humidity in the drying section becomes high and the drying efficiency of grains decreases. On the other hand, when the amount of air blown is considerably larger than the amount of exhausted air in the stationary state, the pressure in the drying section becomes extremely high, so that the air in the drying section easily leaks out from the gap of the casing, and Although a large amount of dust is likely to be emitted to the outside, it is desirable to avoid such dust emission because it pollutes the outside air. The present invention has been made in view of such circumstances, and a dehumidifying dryer capable of avoiding a large amount of the dust discharged to the outside so as not to pollute the outside air while solving the problem that the drying efficiency of grains is reduced. It is intended to be provided.

[0004]

The dehumidifying / drying machine according to the present invention is characterized in that the exhaust air amount of the exhaust air device is smaller than the air flow amount of the air blowing device by a predetermined amount. ..

[0005]

In such a dehumidifying dryer, the pressure of each part in the drying section can be made higher than the external atmospheric pressure by reducing the exhaust air amount by a predetermined amount less than the blown air amount.
External air is prevented from entering the drying section. Therefore,
It is possible to prevent the humidity in the drying unit from increasing due to the invasion of the outside air, and to avoid the decrease in the grain drying efficiency due to the decrease in the humidity. It should be noted that the predetermined amount is set so as to suppress the leakage of air in the drying section which induces the dust emission from becoming so large that the outside air pollution due to the dust emission becomes a problem.

[0006]

As described above, according to the present invention, it is possible to prevent the pollution of the outside air by preventing a large amount of the dust from being discharged to the outside, while solving the conventional problem that the efficiency of drying grain is lowered. it can.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of a dehumidifying dryer of the present invention. The grain dryer is a dehumidifying device 2 (blowing means B) for blowing dehumidified air to a drying section 1 that contains grains for drying. And an exhaust fan 3 (an example of the exhaust means C) that sucks and discharges the air in the drying unit 1 and exhausts the air. Further, a circulation device 4 for circulating and moving the grain in the drying unit 1, a control unit 5 for controlling each unit, and the like are also provided. The drying unit 1 and the dehumidifying device 2 are connected via a duct 6 for blowing air, and a drag-type first air amount sensor S1 as a blowing amount detecting means and air flowing through the duct 6 are connected to the duct 6. A blower thermometer 37 for measuring the temperature of the above and a heater 38 for heating the air flowing therethrough as necessary are provided. Further, the drying section 1 and the exhaust fan 3 are connected via a duct 8 for exhaust air, and the duct 8
In addition, the drag type second air flow sensor S as exhaust air flow rate detection means
Two are provided.

A storage space K for storing grains for drying is formed inside the drying unit 1, and the storage space K communicates with a duct 6 for blowing air and a duct 8 for exhausting air. A plurality of ventilation paths 7 are formed. Each ventilation passage 7
Is configured by arranging a frame having a mountain shape with an open bottom in a cross-sectional shape. In addition, in the drying unit 1,
Pressure gauges (not shown) for measuring the static pressures of the spaces inside the drying section 1 formed above and below the storage space K are also provided.

In the storage space K, there are provided an equalizer 10 for evenly distributing grains from above and a rotary valve 12 arranged in a gap between the inclined plates 11 for discharging grains little by little from the gap. There is. When the rotary valve 12 is driven, the grains in the storage space K are cut out and discharged downward. The amount of grains discharged is balanced with the amount of grains distributed and supplied from the leveling device 10. Come to do. That is, the rotary valve 12 constitutes a part of the circulation device 4, and when it is driven, the grain in the drying section 1 is maintained in a state of circulating movement while maintaining the balanced state (circulation state). It When it is desired to stop the circulation movement and switch the grain in the drying unit 1 to a stationary state (stationary state), the drive of the rotary valve 12 is stopped.

The circulation device 4 has a lower screw conveyor 2 for laterally conveying grains discharged from the storage space K at appropriate intervals by intermittently driving the rotary valve 12.
5, an elevator 26 for hoisting the grains laterally conveyed by the lower screw conveyor 25, an upper screw conveyor 27 for laterally conveying the grains hoisted by the elevator 26, and the like.

The dehumidified air from the dehumidifying device 2 is supplied to the ventilation passage 7 via the air supply frame 13 and exhausted from the ventilation passage 7 to the outside via the exhaust frame 14. In the air supply frame 13,
A plurality of shutoff valves 15 as shutoff means for selectively shutting off the flow of dehumidified air to a part of the drying unit 1 are provided as means for preventing blowout of dehumidified air supplied to grain. That is, when the amount of grain input into the drying unit 1 is large and the air passage 7 is full of grains, all the plurality of shutoff valves 15 are opened, and when the amount of grain input is small and there is almost no grain in the air passage 7. All of the plurality of shutoff valves 15 are closed, and when the grain input amount is between the two cases described above, the upper one of the plurality of shutoff valves 15 is closed and the lower one is opened according to the grain input amount. In this state, the dehumidified air is supplied to the grain while the blow-through is prevented.

In the figure, 30 is a dust removing device and 31 is a storage space K.
Is a full-scale meter for detecting whether or not the grains are stored in a full state, 32 is a grain thermometer for detecting the temperature of the grain, and 33 is a single-grain moisture meter for measuring the moisture of the grain in the drying unit 1. Is.

The inside of the dehumidifier 2 is divided into upper and lower parts, and a condenser 16 and a first blower fan 17 are provided in an upper part 2A, and an evaporator 18, a second blower fan 19 and a compressor 22 are provided in a lower part 2B. Each is provided and a heat pump circuit is configured. And capacitor 1
6 has a function of heating the outside air, and the evaporator 18 has a function of dehumidifying the outside air.

Vent 2 that connects the upper part 2A and the lower part 2B.
The dampers 20A and 21A for adjusting the amount of dehumidified air flowing from the lower portion 2B to the upper portion 2A through the vent holes 20 are provided at the exhaust port 21 of the 0 and the lower portion 2B, respectively. These dampers 20A and 21A are configured to be opened and closed in an anti-reverse manner, and when one damper 21A is fully closed, the other damper 20A is fully opened and the evaporator 18
All of the dehumidified air that has been cooled and dehumidified in 1 is added to the upper portion 2A via the ventilation port 20. Further, when the damper 21A is fully opened, the damper 20A is fully closed, and all the air that has been cooled and dehumidified by the evaporator 18 is discharged to the outside, and only the air heated by the condenser 16 is sent to the duct 6. Become.

In the figure, 34 is a temperature sensor for detecting the dry-bulb temperature of the outside air, and 35 is a humidity sensor for detecting the humidity of the outside air. Although not described in detail, these sensors 34, 35
The opening degrees of the dampers 20A and 21A are determined based on the information of.

The control unit 5 is composed of a combination of a first control unit 5A provided in the lower portion of the drying unit 1 and a second control unit 5B provided in the upper portion of the dehumidifying device 2. Sensing information from each of the above-mentioned sensors is as shown in FIG.
It is input to the control unit 5 (first control unit 5A or second control unit 5B). Then, the first control unit 5A controls the exhaust fan 3
While controlling the rotary valve 12 and the like, the second control unit 5
B controls the shutoff valve 15, the first blower fan 17, the second blower fan 19, the dampers 20A, 21A, and the like. By the way, the input amount information of the grain to the drying unit 1 (the weight of the grain input to the drying unit 1 and the like) is also set and input to the second control unit 5B. The input amount information is the first input via the signal line. It is also transmitted to the control unit 5A.

The controller 5 controls the exhaust fan 3 and the blower fans 17, 1 to adjust the blown air amount and the exhausted air amount.
This is done by controlling the operation of 9. In particular,
The control unit 5 first opens and closes a plurality of shutoff valves 15 to prevent blow-through of the dehumidified air on the basis of the input amount information, and blows the air according to the input amount information (for example, 0.3 m ^3). / S · ton), the operation control of the blower fans 17 and 19 is performed based on the input information from the first air flow sensor S1, and the dehumidification is performed while maintaining the blown air volume obtained by the control. Dehumidified air is blown from the device 2 to the drying unit 1. Moreover, by using the input information from the second air flow sensor S2, the exhaust fan 3
Is operated so that the exhaust air amount is smaller than the air blowing amount by a predetermined amount. It should be noted that the predetermined amount is such an amount that the leakage of the air in the drying unit 1 that induces the dust emission to the outside is suppressed to such an extent that the outside air pollution due to the dust emission becomes a problem.

The control for reducing the exhaust air amount by the predetermined amount from the air blowing amount is specifically performed as described below. That is, the static pressures of the spaces above and below the storage space K are measured as described above and input to the controller 5.
The control unit 5 uses the input information to control the operation of the exhaust fan 3 and the blower fans 17 and 19 so that the static pressure falls within the lowest set pressure (for example, 0 to ₅ mmH ₂ O). .. This is because if the static pressure is set to the lowest possible set pressure as described above, a large amount of dust is suppressed from being discharged.

Next, another embodiment will be described. As means for obtaining information on the amount of grain input to the drying section 1, there is the following means in addition to using the information set and input to the control section 5 as in the above-described embodiment. For example,
A means for detecting the amount of stored grains in the drying section 1 (for example, a large number of sensors arranged at appropriate intervals in the vertical direction of the storage space K) is provided in the drying section 1 and directly obtained by the detection information. It is also conceivable to obtain information regarding the grain storage amount as the input amount information.

Further, the specific structure of each part can be variously changed, for example, the blocking means 15 is constituted by a vertically sliding type blocking member. Further, the present invention can be applied to a dehumidifying dryer in which the structure of the drying unit 1 is not of the grain circulation type as described above but of the grain storage type.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing a grain dryer according to the present invention.

[Explanation of symbols]

 1 Drying section B Blower means C Blower means

Claims (1)

Claim: What is claimed is: 1. A blower (B) for blowing dehumidified air to a drying section (1) for storing grains for drying, and an exhaust for discharging the air of the drying section (1). A dehumidifying / drying machine provided with an air blower (C), wherein the amount of air blown out of the air blower (C) is smaller than the amount of air blown by the air blower (B) by a predetermined amount. Machine.