JP2004166587A - Soil sterilizing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a soil sterilizing machine for sterilizing soil with low consumption energy while maintaining moderate moisture content of the soil. <P>SOLUTION: The soil sterilizing machine works as follows. Soil 7 is held in a sterilizing tank 1 encircled with a thermal insulation wall and equipped with a hot air discharge pipe 4 at the bottom and the opening of the tank is covered with a thermal insulation cover 8. Air is then fed into the hot air discharge pipe 4 by a blower 2 while heating the air with an electric air heater 3, and the resulting hot air is blown via the discharge port 5 of the pipe 4 into the soil 7 and returned from the upper space via a suction pipe 6 to the blower 2. In this way, the soil 7 is sterilized while circulating the hot air in the sterilizing tank 1. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a soil disinfecting machine for killing harmful soil bacteria and weed seeds living in soil for horticultural use.
[0002]
[Prior art]
As a method for killing harmful soil bacteria and weed seeds in soil, a method using a soil disinfectant such as methyl bromide has been conventionally known. However, the method using a soil disinfectant has a problem of environmental protection such that methyl bromide leads to destruction of the ozone layer of the earth and will soon be banned.
[0003]
On the other hand, as a soil disinfecting machine not using a soil disinfectant, there is a soil disinfecting machine using high-temperature steam as shown in FIG. In FIG. 3, reference numeral 10 denotes a disinfection tank, 11 denotes a boiler, 12 denotes a steam ejection pipe, 13 denotes an ejection hole, 14 denotes soil, and 15 denotes a cover sheet.
[0004]
A steam ejection pipe 12 having a large number of ejection holes 13 is provided at the bottom of the disinfection tank 10, and a boiler 11 is connected to an outer end thereof. The soil 14 to be disinfected is put into such a disinfection tank 10, and the steam generated by the boiler 11 is sent to a steam ejection pipe 12 to be ejected from the ejection hole 13 into the disinfection tank 10. Discharge from the gap to the outside. As a result, the soil 14 is heated by the steam, and harmful soil bacteria and weed seeds contained therein are killed.
[0005]
In addition, the following is a conventional document related to such a soil disinfection machine.
[Patent Document 1]
Japanese Utility Model Publication No. Sho 62-136154
[Problems to be solved by the invention]
However, the conventional soil disinfecting machine has a problem that the soil 14 becomes excessively moist due to the passage of steam and becomes sticky, and it takes time to dry the soil after disinfection. In addition, there is also a problem that energy loss increases because the steam after passing through the soil is discharged to the outside and discarded.
[0007]
In view of such problems, an object of the present invention is to make it possible to disinfect soil with low energy loss while maintaining an appropriate water content without imposing a burden on the environment.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, a soil disinfecting machine of the present invention includes a disinfecting tank surrounded by a heat insulating wall and containing soil therein, a hot air discharge pipe disposed at the bottom of the disinfecting tank, and a hot air discharge pipe. A blower that feeds air to the blower, an air heater that heats the air sent by the blower, a heat insulating cover that covers an opening of the disinfection tank, and a suction pipe that communicates the upper space of the disinfection tank with the blower. It is characterized by the following. In this way, the soil can be disinfected with a small energy loss while maintaining an appropriate water content without imposing a burden on the environment.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing an embodiment of the present invention. In FIG. 1, 1 is a disinfection tank, 2 is a blower, 3 is an air heater, 4 is a hot air discharge pipe, 5 is a discharge hole, 6 is a suction pipe, 7 is soil, 8 is a heat insulating cover, and 9 is a temperature sensor.
[0010]
The disinfection tank 1 is surrounded by a heat insulating wall filled with a heat insulating material such as glass wool between steel plates at the bottom and the periphery, and a hot air discharge pipe 4 having a large number of discharge holes 5 is arranged on the inner bottom. Is established. The hot-air discharge pipe 4 is connected to the blower 2 via an electric heat type air heater 3, and the blower 2 communicates with the upper space of the disinfection tank 1 by a suction pipe 6. In addition, a door 1a that opens and closes in a double-opening manner is provided on the side surface of the disinfection tank 1 so that the soil 7 can be put in and out of the bucket truck.
[0011]
As the blower 2 and the air heater 3, for example, in a soil disinfecting machine having a processing capacity of 1.2 m ³ , a 0.75 Kw blower and a 4.5 Kw heater can be used.
[0012]
The soil 7 to be disinfected is put in such a disinfection tank 1, and the blower 2 and the air heater 3 are turned on. As a result, the air sent by the blower 2 is heated by the air heater 3, and hot air is discharged into the soil 7 from the discharge holes 5 of the hot air discharge pipe 4. The exhaled hot air rises in the soil 7 and goes out into the upper space of the disinfection tank 1, and then is sucked by the suction pipe 6 and returns to the blower 2. Thus, hot air is circulated in the disinfection tank 1 in the direction indicated by the arrow in FIG.
[0013]
At this time, the upper opening of the disinfection tank 1 is covered with the heat insulating cover 8 without any gap, so that the air in the disinfection tank 1 does not leak to the outside. In this way, the moisture originally contained in the soil 7 is vaporized and circulated in the disinfection tank 1 so that the soil 7 is not dried and has no excess moisture such as steam disinfection. .
[0014]
Further, a temperature sensor 9 is put in the soil 7, and the on / off of the air heater 3 is controlled based on the detected output, so that the temperature of the soil 7 is maintained at 60 ° C to 70 ° C. In this soil disinfection machine, after the temperature of the soil 7 has risen to a predetermined temperature after the start of operation, the temperature can be maintained only by supplementing the heat leaking from the wall of the disinfection tank 1 or the surface of the heat insulating cover 8 with the air heater 3. Moreover, since the disinfecting tank 1 and the heat insulating cover 8 have high heat insulating properties, the amount of heat that leaks out is small, and the energy loss is very small.
[0015]
Further, since an electric heater is used as the air heater 3, unlike the combustion type of kerosene or the like, safe and night-time unmanned operation is possible, and temperature management becomes easy. In addition, there is no smoke emission, oil leakage, etc., and the environment is friendly.
[0016]
When the capacity of the disinfection tank 1 is large, the hot air discharge pipe 4 may be branched from the air heater 3 as shown in FIG. By doing so, the hot air from the blower 2 and the air heater 3 spreads evenly over the soil 7 in the disinfecting tank 1 and uneven heating is reduced. When the capacity of the disinfection tank 1 is even larger, a plurality of blowers 2 and air heaters 3 are provided, and a hot air discharge pipe 4 as shown in FIG. 2 can be connected to each of them.
[0017]
【The invention's effect】
The present invention is configured as described above, and has the following effects.
That is, the soil was contained inside the disinfection tank surrounded by the heat insulating wall, the opening was covered with the heat insulating cover, and the hot air was circulated by the blower and the air heater. The water stays in the disinfection tank as it is, so that the soil can be disinfected without drying the soil and without having excessive moisture while maintaining an appropriate water content. After the temperature of the soil is raised to the specified temperature, the heat generated by the air heater only needs to compensate for the leakage from the walls of the disinfection tank and the surface of the heat insulating cover. Can be. Moreover, it does not emit harmful substances and does not burden the environment.
[Brief description of the drawings]
FIG. 1 is a diagram showing one embodiment of the present invention.
FIG. 2 is a plan view of a hot air discharge pipe.
FIG. 3 is a diagram showing a conventional soil disinfecting machine using steam.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Disinfection tank 2 ... Blower 3 ... Air heater 4 ... Hot air discharge pipe 5 ... Discharge hole 6 ... Suction pipe 7 ... Soil 8 ... Insulation cover 9 ... Temperature sensor

Claims (1)

A disinfecting tank surrounded by heat insulating walls and containing soil therein, a hot air discharge pipe disposed at the bottom of the disinfecting tank, a blower for sending air to the hot air discharge pipe, and heating the air sent by the blower A disinfecting machine comprising: an air heater, a heat insulating cover that covers an opening of the disinfecting tank, and a suction pipe that communicates an upper space of the disinfecting tank with the blower.

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