JPS608785B2 - Heat pump type tobacco drying device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a clean heat pump type tobacco drying device that does not require any fuel such as petroleum and does not emit environmental pollutants.

Current cigarette drying equipment is a batch-type circulating air drying equipment that consists of a tobacco storage chamber, a ventilation mechanism, a circulating air blower, a heating air blowing chamber equipped with a kerosene furnace for generating hot air, and a temperature/humidity regulator.

Tobacco curing is based on a standard temperature and humidity schedule created according to the variety and the characteristics of the harvested leaves, and the temperature and humidity are set periodically, and the overflow humidity is gradually changed to promote curing, making it ideal for smoking purposes. It is a process for producing adapted leaf tobacco. Therefore, according to changes in the condition of tobacco,
Correct setting of temperature and humidity in the drying chamber is a requirement for tobacco drying.

At the same time, during curing, various substances such as nicotine, ammonia, carbonyl compounds, etc. are dispersed from the tobacco hollyhock as a result of biochemical reactions. Furthermore, since the heat source required for evaporation of water in cigarettes is mainly obtained from the combustion heat of kerosene, there is a disadvantage that combustion gas containing air pollutants such as nitrogen oxides after heat exchange is released into the atmosphere from the chimney. .

Next, the humidity in the drying room is determined by automatically operating the ventilation mechanism through a humidity controller that receives electrical signals from various humidity sensors such as wet bulb temperature, dew point, relative humidity, and wet/dry bulb temperature difference. adjusted.

The ventilation mechanism is a humidity control method that utilizes the phenomenon that the absolute humidity of the air in the drying room is always higher than the absolute humidity of the atmosphere, and at the same time, the humidity in the drying room air that is consumed due to the respiration of cigarettes is contained. It plays the role of supplying oxygen. In this way, cigarette drying equipment uses ventilation as the most economical method to adjust the humidity in the drying room and supply oxygen (in other words, to emit carbon dioxide).As a result, nicotine and other substances that are naturally dispersed from the cigarettes are removed. The disadvantage is that it releases into the atmosphere. The present invention aims to eliminate these conventional drawbacks and provide a tobacco drying device that has excellent controllability of temperature and humidity, which is a requirement for tobacco drying, and has high thermal efficiency.

Hereinafter, embodiments of the present invention will be described based on the figures.
As shown in the figure, a partition wall 2 is provided in a drying chamber 1 to form a tobacco accommodating chamber 3 and a heating and blowing chamber 4, which are vertically aligned with each other.

An inlet 5 and an exhaust port 6 are provided in the upper part of the heating and blowing chamber 4, and a circulation blower 7 and a heat pump condenser 9 are provided inside. Dampers 2 are connected to the intake port 5 and the exhaust port 6, respectively.
1 and 22, and the dampers 21 and 22 transmit the signal from the humidity sensor 16 provided in the tobacco storage chamber 3 to the humidity controller 1.
8, and the humidity in the drying chamber 1 is adjusted by opening/closing the output according to the deviation from the set value. The circulation blower 7 continues to blow air into the tobacco storage chamber 3 during the drying period. Note that the humidity sensor referred to herein refers to a sensor that directly or indirectly senses humidity, such as wet bulb temperature, fog point, relative humidity, and wet/dry bulb temperature difference. An exhaust duct 20 having an outside air intake 19 is carried through the exhaust port 6, and an exhaust fan 13,
A heat pump evaporator 11 and an activated carbon adsorber 14 are provided. The condenser 9 in the heating ventilation chamber 4 and the evaporator 11 in the exhaust duct 20 are connected to a cold soot steam pipe 23 and a cold soot liquid pipe 24.
A compressor 8 and a solenoid valve 12 are provided in the middle of the refrigerant vapor pipe 23, and an expansion valve 10 is provided in the cold soot liquid pipe 24. The temperature controller 17 receives a signal from the dry bulb temperature sensor 15 installed in the tobacco storage chamber 3.
transmits an output according to the deviation from the set value, so for example, if the detected value of the dry bulb temperature sensor 15 does not reach the set value, the solenoid valve 12 provided in the refrigerant vapor pipe 23 opens and the pressure increases. The switch is operated to operate the compressor 8, and high-pressure refrigerant vapor is sent to the condenser 9, thereby heating the circulating air in the drying chamber.

The cold soot liquid flows out from the condenser 9 through the cold soot liquid pipe 24, passes through the expansion valve 10, becomes a low-temperature refrigerant, and enters the evaporator 11.
flows into. The low-temperature cold soot that has flowed into the evaporator 11 is vaporized by obtaining the head heat or latent heat of the mixed gas of outside air and drying room exhaust gas or only the outside air, and is changed into low-pressure refrigerant vapor, which is sent to the compressor 8 again. In this way, the temperature inside the drying chamber is increased. If the heat pump continues to operate, the temperature in the drying room will exceed the set temperature, and the temperature controller 17
The solenoid valve 12 is closed by the signal from the compressor 8, the pressure switch is activated, and the compressor 8 is stopped.

As a result, heat supply from the condenser 9 is stopped.

Although the drawings show a system in which the temperature in the drying chamber is controlled by on/off control by opening and closing the solenoid valve 12, the present invention is not limited to this. For example, the temperature controller 1
It is also effective to provide a temperature controller with a proportional operation in place of the temperature controller 7 and connect a frequency converter, thereby continuously controlling the rotation speed of the compressor 8 according to the deviation from the temperature setting value. In this case, stepless control of the amount of heat supplied from the condenser 9 becomes possible. In addition, in the figure, 25 is a perforated floor plate, 26 is a lifting machine, and 27
indicates a hanging leaf tobacco. The tobacco drying process consists of a yellowing period, a color fixation period, and a bone drying period. During each period, the temperature is maintained at an optimum level, and the content components are changed by enzyme action and moisture evaporates in parallel. It is finished into leaf tobacco that is suitable for use and storage. At the beginning of the yellowing period, it is a preparation stage to raise the temperature to 36 to 38o0, which is enough to cause the tobacco to yellow.Also, at the end of the drying period, the amount of moisture evaporated from the tobacco is small, so the drying process is carried out during these periods. The indoor air is completely circulated, and the dampers 21 and 22 are closed.

At this time, of course, the heat source for evaporating the cold soot cannot depend on the exhaust heat from the drying chamber, so another heat source is required. Normally, tobacco is dried during periods of high temperature, so the heat from the outside air can be used as a heat source.
The exhaust fan 13 in the exhaust duct 20 is constantly rotating, and when the damper 22 is closed, the outside air intake 19
More outside air flows in, and the evaporator 11 is heated by the outside air heat.

When the damper 22 is open, the exhaust air from the drying chamber is mixed with outside air, and the heat is utilized.

As mentioned above, the exhaust gas from the drying room contains healing ingredients such as nicotine, but when it comes into contact with the evaporator 11 and is cooled, it condenses on the surface of the evaporator 11 and is absorbed together with the condensed water. part is removed. The remainder of the thinly dispersed components is adsorbed and removed by the activated carbon adsorber 14 connected to the evaporator 11, making it possible to completely purify the exhaust gas. Partial removal of the barrel components by the evaporator 11 serves to extend the shelf life of the activated carbon in the adsorber 14. As is clear from the above explanation, according to the present invention, the soot condensation heat of the heat pump operated by electricity is used instead of the conventional kerosene-fired furnace as the heat source of the drying chamber, and furthermore, the drying chamber exhaust gas is absorbed, adsorbed and removed. A tobacco drying device that does not emit air pollutants is provided.

Hereinafter, the operational results of the tobacco drying apparatus based on the present invention will be explained.

The tobacco drying device is a panel assembly drying room with a hanging area of 3.3 cm and a heat pump with 8 compressors and an output of 2.2 kW. Based on the air temperature during the tobacco drying period and the maximum temperature setting of the drying room, the evaporation temperature was set to 1000, the condensation temperature was set to 80 qo, and Freon 12 was used as the cold soot. FIG. 2 shows the dry bulb temperature of the air in the drying chamber from the start to the end of drying and the actual measured values for the set values of the fog point, and the temperature and humidity can be controlled reliably and easily.

Next, one of the features of the present invention is that a mixed gas or outside air is used as a heat source for evaporating the refrigerant. Evaporator 11
The air flowing into the
Since exhaust fans 13 and 3 are used, the air volume is constant regardless of whether or not there is exhaust air from the drying room, and if there is exhaust air from the drying room, the amount of outside air intake decreases by that amount, and the drying room exhaust If there is no air, only outside air will be used. The amount dependent on outside air in the total heat recovered by the evaporator 11 during the entire drying period was about 40%, and the mixed gas system functioned effectively in increasing the heat exchange efficiency of the evaporator 11. Furthermore, the performance of the activated carbon adsorber 14 that follows the evaporator 11 was confirmed to be effective through a vague test of the Namiai gas discharged outside the system. Finally, when comparing the energy required for the heat pump type drying device based on the present invention and the conventional kerosene-fired drying device, the kerosene heating method uses 6970 kcal per 9 lbs of dried Aoi tobacco, while the heat pump type uses 1430 kcal, Approximately 1
Drying was possible with an energy of /5.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an embodiment of the drying apparatus of the present invention, and FIG. 2 is a graph showing the temperature course in a drying chamber using the drying apparatus of the present invention. 1... Drying room, 2... Partition wall, 3.
...Tobacco storage room, 4...Heating ventilation room,
5...Inlet, 6...Exhaust port, 7...
...Circulating blower, 8...Compressor, 9...
・Condenser, 10... Expansion valve, 11...
Evaporator, 12... Solenoid valve, 13... Exhaust fan, 14... Activated carbon adsorber, 15... Dry bulb temperature sensor, 16... Humidity sensor , 17・
...Temperature controller, 18...Humidity controller,
19... Outside air intake, 20... Exhaust duct, 21... Damper, 22... Damper, 23... Medium steam pipe, 24... Refrigerant liquid pipe, 25... Perforated floor plate, 26... Hanging machine, 27... Tobacco leaves. Leopard drawing screen 2

Claims (1)

[Scope of Claims] 1. In a circulating air drying device, an exhaust duct having an outside air intake port communicating with the exhaust port is provided, an exhaust fan and a heat pump evaporator are provided in the exhaust duct, and a heat pump condenser is provided in the heating ventilation chamber. It is characterized by controlling the opening and closing of dampers installed at the intake and exhaust ports based on signals from a humidity sensor installed in the drying chamber, and further controlling refrigerant circulation in the heat pump based on signals from a dry bulb temperature sensor. A heat pump type tobacco drying device. 2. In a circulating air drying device, an exhaust duct having an outside air intake port communicating with the exhaust port is provided, an exhaust fan, a heat pump evaporator, and an activated carbon adsorber are provided in the exhaust duct, and a heat pump condenser is installed in the heating ventilation chamber. The damper provided at the intake and exhaust ports is controlled to open and close based on the signal from the humidity sensor installed in the drying chamber, and the refrigerant circulation in the heat pump is controlled based on the signal from the dry bulb temperature sensor. A heat pump type tobacco drying device.