JP5124521B2 - Fumigation device and fumigation method - Google Patents

Description

  The present invention relates to a fumigation apparatus and a fumigation method. More specifically, the present invention relates to a fumigation apparatus and a fumigation method capable of treating raw plants, grains, wood or feed in a short period of time with a gas containing a high concentration of hydrogen phosphide.

Conventionally, hydrogen phosphide has been used for warehouse fumigation, silo fumigation, container fumigation, etc. of raw plants, grains, wood or feed. However, hydrogen phosphide is a very dangerous gas that may spontaneously ignite at low concentrations (about 1.5% by volume).
As fumigation with hydrogen phosphide, a method is known in which aluminum phosphide tablets are placed in a fumigation chamber and hydrogen phosphide is generated by reaction between aluminum phosphide and moisture in the air. However, the reaction between aluminum phosphide and moisture in the air takes time. For this reason, there is a drawback that it becomes a long-term fumigation and cannot be used for short-time fumigation requiring freshness.
Patent Document 1 and Patent Document 2 propose a hydrogen phosphide generator that generates hydrogen phosphide at a low concentration to the extent that hydrogen phosphide does not ignite. However, these proposals are not suitable for short-time fumigation that requires freshness.

On the other hand, a method of filling a cylinder with hydrogen phosphide and using it for fumigation is also known. However, since hydrogen phosphide is extremely flammable and dangerous, high concentration hydrogen phosphide is diluted to about 1.5% by volume with an inert gas and filled in a cylinder for use in fumigation. . In this method, since a low concentration hydrogen phosphide-containing gas is used, a long fumigation time is required, and there is a disadvantage that it cannot be used for those requiring freshness.
Furthermore, as a method for improving this defect, Patent Document 3 proposes a fumigation device that prevents ignition by using a mixture of high concentration hydrogen phosphide and methyl bromide and that can be fumigated in a short time. . In this proposed apparatus, hydrogen phosphide filled in a cylinder is used as the high concentration hydrogen phosphide. However, hydrogen phosphide cylinders belong to special high-pressure gas, and strict handling is required for their storage, transportation and use.
Further, Patent Document 4 proposes a method that can easily and safely provide a high concentration hydrogen phosphide gas in a fumigation place without using a cylinder and can be fumigated in a short period of time. However, the decomposition rate is not stable due to the change in the temperature of the added water due to the outside air temperature, so that it is difficult to manage the amount of generation over time, and it can only be introduced into one fumigation chamber in a single treatment. In addition, the method using dilute sulfuric acid is regulated because the dilute sulfuric acid corresponds to a deleterious substance under the Poisonous and Deleterious Substances Control Law, and it is necessary to ensure the safety of the user.

Japanese National Patent Publication No. 6-500761 European Patent Application No. 03184040 JP-A-5-161444 Japanese Patent No. 3587401

An object of the present invention is to provide a fumigation apparatus that can stably and quantitatively obtain a high concentration hydrogen phosphide gas at a fumigation place. Another object of the present invention is to provide a fumigation device that can kill live plant, grain, wood or feed pests in a short period of time safely without fear of ignition. Another object of the present invention is to provide a method for fumigating stably and quantitatively with a high concentration of hydrogen phosphide gas at a fumigation site. Another object of the present invention is to provide a fumigation method that can safely kill live plant, grain, wood or feed pests in a short period of time without fear of ignition.
As a result of intensive research that the present inventor has achieved this object, the hydrogen phosphide-containing gas can be stably and quantitatively added by quantitatively adding warm water maintained at a constant temperature to a specific metal phosphide compound. I found out that Further, the present inventors have found that hydrogen phosphide-containing gas can be quantitatively supplied to a plurality of fumigation chambers by utilizing the fact that hydrogen phosphide-containing gas can be obtained stably and quantitatively.

  That is, according to the present invention, the following inventions are provided.

1. (I) an inert gas supply means for supplying an inert gas to the hydrogen phosphide generation tank,
(II) Hot water supply means for supplying hot water to the hydrogen phosphide generation tank, and (III) hydrogen phosphide generation means having a hydrogen phosphine generation tank, a conduit and a jet nozzle,
While supplying an inert gas into the hydrogen phosphine generation tank, hot water is supplied to react the metal phosphide compound in the hydrogen phosphide generation tank with the hot water, and the resulting hydrogen phosphide-containing gas is fumigated. A fumigation device that spouts out.
2. The fumigation device according to item 1, wherein the hot water supply means includes a water tank, a heater, and a pump.
3. 2. The fumigation device according to item 1 above, wherein the hydrogen phosphide generating means has a distributor for ejecting the hydrogen phosphide-containing gas into the plurality of fumigation chambers.
4). A method for fumigating a material to be fumigated using the fumigation device according to the preceding item 1,
(I) introducing at least one metal phosphide compound selected from the group consisting of aluminum phosphide and magnesium phosphide into a hydrogen phosphide generation tank;
(Ii) a step of replacing the air in the hydrogen phosphide generation tank and the conduit with an inert gas; and (iii) supplying hot water at 30 to 70 ° C. while supplying the inert gas to the hydrogen phosphine generation tank. Generating a hydrogen fluoride-containing gas and ejecting the obtained hydrogen phosphide-containing gas into the fumigation chamber at a flow rate of 1 m / second or more;
The process of supplying warm water includes the following first to third stages, and the supply amount of warm water in each stage is the following ratio with respect to the total supply amount,
(A) 1st stage 10-40 weight%,
(B) Second stage 0% by weight,
(C) Third stage 60-90% by weight,
The time required for the second stage is 0.5 to 3 times the time required for the first stage.
A fumigation method characterized by that.
5. The fumigation method according to item 4 above, wherein the temperature of the hydrogen phosphide generation tank is 30 to 98 ° C.
6). 5. The fumigation method according to item 4 above, wherein the hydrogen phosphide-containing gas ejected into the fumigation chamber contains 20 to 99.9% by volume of an inert gas.
7. 5. The fumigation method according to item 4, wherein the hydrogen phosphide-containing gas is jetted into the gas circulated from the fumigation chamber.
8). 5. The fumigation method according to item 4 above, wherein the supply amount of hot water in each stage is 30 to 250 ml / min in the first stage, 0 ml / min in the second stage, and 30 to 360 ml / min in the third stage.

  According to the fumigation apparatus of the present invention, a high concentration hydrogen phosphide-containing gas can be obtained stably and quantitatively at a fumigation place. Further, according to the fumigation apparatus of the present invention, it is possible to kill live plants, cereals, wood or feed pests in a short period of time without worrying about ignition.

  According to the fumigation method of the present invention, fumigation can be carried out stably and quantitatively with a high concentration hydrogen phosphide-containing gas at a fumigation place. Further, according to the fumigation method of the present invention, live plants, grains, wood or feed pests can be killed safely in a short period of time without fear of ignition.

1 is a diagram of an apparatus used in Example 1. FIG. It is a figure of the apparatus used in Example 2. FIG. It is a figure which shows the hydrogen phosphide generation amount per unit time of Example 1 and Comparative Example 1. It is a figure which shows hydrogen phosphide generation amount transition after the reaction start of Example 1. FIG. FIG. 4 is a graph showing the amount of hydrogen phosphide generated per unit time in Example 2.

<Fumigation device>
The fumigation apparatus of the present invention will be described with reference to FIGS. FIG. 2 shows a case where a plurality of fumigation chambers are fumigated. The fumigation apparatus of the present invention includes (I) inert gas supply means, (II) hot water supply means, and (III) hydrogen phosphide generation means, while supplying an inert gas into the hydrogen phosphide generation tank 15, This is a fumigation device that supplies hot water and jets a hydrogen phosphide-containing gas obtained by reacting the metal phosphide compound in the hydrogen phosphide generation tank 15 and warm water into the fumigation chamber (25, 31, 32).

(Inert gas supply means)
The inert gas supply means is means for supplying an inert gas to the hydrogen phosphide generation tank 15. The inert gas supply means preferably has a cylinder 1, a pressure adjustment valve 2, a conduit 10 and a flow rate controller 3. The inert gas supply means is a means for replacing the air in the hydrogen phosphine generation tank 15 and the conduit 18 with an inert gas in advance in order to prevent ignition of hydrogen phosphide. Further, the inert gas and the generated hydrogen phosphide gas are mixed and jetted into the fumigation chamber (25, 31, 32) as a hydrogen phosphide-containing gas having a predetermined flow rate. Examples of the inert gas include carbon dioxide gas and nitrogen gas.

(Hot water supply means)
The hot water supply means is means for supplying hot water to the hydrogen phosphide generation tank 15. The hot water supply means preferably has a water tank 4, a heater 5, and a pump 7. Moreover, it is preferable to have the water meter 35, the water amount regulator 36, the nozzle 12, the circulation line 9, the three-way valve 8, and the thermometer 39. The nozzle 12 is preferably a spray nozzle having a full conical shape. The hot water supply means is means for supplying hot water to the hydrogen phosphide generation tank 15. The warm water in the water tank 4 is preferably supplied to the hydrogen phosphide generation tank 15 while being maintained at a constant temperature by the heater 5 while being circulated through the circulation line 9. The pump 7 is used for circulation and liquid feeding to the hydrogen phosphide generation tank 15.

(Hydrogen phosphide generation means)
The hydrogen phosphine generating means includes a hydrogen phosphine generating tank 15, a conduit 18 and a jet nozzle 20. The hydrogen phosphide generating means preferably includes a thermometer 13, a pressure gauge 14, a heater 16, a metal phosphide compound inlet 17, a valve 19, and an ejection nozzle 20.
The shape of the ejection nozzle 20 is preferably a shape that allows a flow rate of 1 m / second or more when a hydrogen phosphide-containing gas is ejected, and a circular cylindrical one is often used.
The hydrogen phosphide generating means is means for reacting water and a metal phosphide compound. Further, the generated hydrogen phosphide and an inert gas are mixed to form a hydrogen phosphide-containing gas. Further, it is a means for jetting the obtained hydrogen phosphide-containing gas into the fumigation chamber at a predetermined flow rate. The hydrogen phosphide-containing gas can be ejected to the plurality of fumigation chambers (25, 31, 32) via the distributor 27. The hydrogen phosphide generation tank 15 is preferably charged with a metal phosphide compound 26 selected from the group consisting of aluminum phosphide and magnesium phosphide.

<Fumigation method>
The fumigation method of the present invention is a method for fumigating the material to be fumigated using the above apparatus.

(Fumigation)
In the fumigation method of the present invention, as fumigated products, fruits and vegetables such as banana, pineapple, lemon, grapefruit, orange, kiwifruit and avocado, lettuce, okra, asparagus, peas and other vegetables, chrysanthemum, carnation, orchid, Cut ferns, bulbs such as tulips and gladiolus, seedlings such as orchids, raw plants including ears, seeds, etc., cereals such as rice, wheat and soybeans, feed and rice materials such as oil lees and alfalfa pellets, southern ocean Examples thereof include wood.
The fumigation method of the present invention includes the following steps (i) to (iii).

(Process (i))
Step (i) is a step of introducing at least one metal phosphide compound selected from the group consisting of aluminum phosphide and magnesium phosphide into the hydrogen phosphide generation tank 15. The metal phosphide compound is introduced from the metal phosphide compound inlet 17. The amount of the metal phosphide compound is preferably 50 to 6000 g.

(Step (ii))
Step (ii) is a step of replacing the air in the hydrogen phosphide generation tank 15 and the conduit 18 with an inert gas. The inert gas flows from the cylinder 1 through the conduit 10 through the conduit 10 to the hydrogen phosphine generation tank 15 and the conduit 18 by the aforementioned inert gas supply means, and the air in these is replaced with the inert gas. It is preferable for safety to replace the air in the hydrogen phosphide generation tank 15 and the conduit 18 with an inert gas in advance.

(Process (iii))
In step (iii), while supplying an inert gas to the hydrogen phosphide generation tank 15, hot water of 30 to 70 ° C. is supplied to generate hydrogen phosphide, and the obtained hydrogen phosphide-containing gas is 1 m in the fumigation chamber. This is a step of jetting at a flow rate of at least / sec.
The inert gas is supplied from the cylinder 1 through the conduit 10 to the hydrogen phosphide generation tank 15 by the aforementioned inert gas supply means. The supply amount of the inert gas is such that the ejection speed from the ejection nozzle 20 with the inert gas alone is 1 m / second or more, preferably 1 to 25 m / second, more preferably 1 to 5 m / second.

Hot water is supplied from the water tank 4 through the conduit 11 to the hydrogen phosphide generation tank 15 by the above-described hot water supply means. The supplied hot water reacts with the metal phosphide compound 26 in the hydrogen phosphide generation tank 15 to generate hydrogen phosphide gas. The shape of the nozzle 12 is preferably a spray nozzle having a full conical shape. The cylindrical nozzle is not stable because the spraying range of the supplied hot water is narrow and the generation of gas is slow.
The hot water temperature is in the range of 30 to 70 ° C, preferably 35 to 45 ° C. When the hot water temperature is lower than 30 ° C., the generation of hydrogen phosphide-containing gas becomes too slow, and when it is higher than 70 ° C., the generation of hydrogen phosphide-containing gas becomes too fast and it is difficult to generate stable hydrogen phosphide-containing gas. Become.

The supply of warm water includes the following first to third stages, and the supply amount of warm water in each stage is the following ratio with respect to the total supply amount.
(A) 1st stage 10-40 weight%,
(B) Second stage 0% by weight,
(C) Third stage 60-90% by weight,
When the supply amount of warm water is less than 10% by weight in the first stage and when the supply amount of warm water is less than 60% by weight in the third stage, the reaction is slow and it is difficult to achieve the object of the present invention. In addition, when the supply amount of hot water exceeds 40% by weight in the first stage, and when the supply amount of hot water exceeds 90% by weight in the third stage, the reaction becomes too fast and the risk of ignition increases, making stable supply difficult. Become.
The total amount of hot water supplied is preferably 100 to 800 ml, more preferably 440 to 630 ml, per 100 g of the metal phosphide compound.

The time required for the second stage is 0.5 to 3 times, preferably 1 to 3 times, more preferably 1 to 2 times the time required for the first stage. By providing a time during which the second stage of warm water is not supplied, rapid generation of hydrogen phosphide gas can be suppressed and stable fumigation can be achieved.
The time required for the third stage is 0.5 to 3 times, preferably 1 to 3 times, more preferably 1.3 to 3 times the time required for the first stage.
The supply amount of hot water is preferably 30 to 250 ml / min in the first stage, 0 ml / min in the second stage, and 30 to 360 ml / min in the third stage. More preferably, it is 60 m to 200 ml / min in the first stage and 60 to 260 ml / min in the third stage. If it is less than 30 ml / min in the first and third stages, the reaction rate becomes slow and it is difficult to achieve the object of the present invention, and if it exceeds 250 ml / min in the first stage and 360 ml / min in the third stage, the reaction becomes too fast. The risk of ignition increases and stable supply becomes difficult.

The temperature in the hydrogen phosphide generation tank 15 is preferably 30 to 98 ° C, more preferably 40 to 85 ° C. If the temperature is lower than 30 ° C., the progress of the reaction becomes insufficient. If the temperature is higher than 98 ° C., the reaction is vigorous and cannot be controlled.
The contact reaction between the metal phosphide compound and hot water is preferably carried out batchwise. The reason is that the batch system is suitable for obtaining a specific amount of high concentration hydrogen phosphide gas at the fumigation location, corresponding to the size of the fumigation chamber and the quantity and type of objects to be fumigated. .
The generated hydrogen phosphide gas and the inert gas are mixed in the hydrogen phosphide generation tank 15 to become a hydrogen phosphide-containing gas. The inert gas content in the hydrogen phosphide-containing gas is preferably 20 to 99.9% by volume, more preferably 40 to 99.9% by volume. Ignition of hydrogen phosphide is suppressed by the inert gas.
The obtained hydrogen phosphide-containing gas is ejected into the fumigation chamber 25 through the conduit 18 at a predetermined flow rate. The hydrogen phosphide-containing gas is preferably ejected to the circulation line 24 of the fumigation chamber.

The flow rate of the hydrogen phosphide-containing gas ejected into the fumigation chamber is 1 m / second or more, preferably 1 to 50 m / second, more preferably 1 to 5 m / second. When the flow rate is slower than 1 m / sec, hydrogen phosphide is likely to ignite, which is not preferable.
Live plants, grains, wood or feed is fumigated by the hydrogen phosphide-containing gas blown into the fumigation chamber.
The hydrogen phosphide-containing gas is preferably ejected into the gas circulated from the fumigation chamber and introduced into the fumigation chamber or chambers directly or via a distributor. If the jet nozzle diameter is large and the flow rate of the hydrogen phosphide-containing gas cannot be maintained and there is a risk of ignition, the hydrogen phosphide-containing gas is jetted into the gas circulated from the fumigation chamber and mixed to contain hydrogen phosphide It becomes possible to rapidly dilute the hydrogen phosphide concentration in the gas to a concentration that does not ignite.

Example 1
A hydrogen phosphide-containing gas was obtained by the following method using the apparatus shown in FIG.
After putting about 8 liters of water into the water tank 4, when the water supply pump 7 was operated, the three-way valve 8 was operated so that water was circulated to the water tank 4 via the circulation line 9. Subsequently, the warm water in the water tank 4 was heated by the heater 5 so that the temperature became 40 ° C., and the water supply pump 7 was operated.

(Process (i))
The hydrogen phosphide generation tank 15 having a capacity of about 40 liters was previously heated by the heater 16 until the indicated value of the thermometer 13 reached 40 ° C. After the indicated value of the thermometer 13 reached 40 ° C., 300 g of an aluminum phosphide agent 26 (Epifume (registered trademark) sold by Ikeda Kogyo Co., Ltd.) was introduced from the inlet 17.

(Step (ii))
The pressure was adjusted to 0.3 MPa with the pressure control valve 2, the flow rate was adjusted to 30 liters / minute with the flow rate controller 3, and nitrogen gas was introduced from the nitrogen gas cylinder 1 into the hydrogen phosphide generation tank 15 through the conduit 10. . At this time, the valves 19 and 38 were closed.
The pressure in the hydrogen phosphating tank 15 is confirmed with the pressure gauge 14, and nitrogen gas is sealed until the indicated value reaches 0.04 MPa. When the pressure reaches 0.04 MPa, the nitrogen gas sealing is stopped and the valve 19 is opened. The gas was removed and the pressure in the hydrogen phosphide generation tank 15 was returned to atmospheric pressure. The nitrogen gas filling and degassing operations were repeated 5 times.

(Process (iii))
Then, as a result of measuring the oxygen concentration in the hydrogen phosphine generating tank 15 from the sampling port (A) with an oxygen concentration meter while introducing nitrogen gas into the hydrogen phosphide generating tank 15 at a flow rate of 30 liters / minute, 0.9. %Met.

First stage After opening the valves 22 and 23 and operating the blower 21, it is confirmed by the thermometer 39 that the water temperature of the water tank 4 has reached 40 ° C., and the three-way valve 8 is operated to connect the nozzle 12 through the conduit 11. Hot water was introduced into the hydrogen phosphide generation tank 15 to start the reaction. At this time, the flow rate of the warm water was adjusted to 192 ml / min by the water amount controller 36.
The hydrogen phosphide obtained in the hydrogen phosphine generating tank 15 was mixed with nitrogen gas and other gases and jetted from the jet nozzle 20 into the piping of the circulation line 24 through the conduit 18. The air in the fumigation chamber 25 was circulated by opening the valves 22 and 23 and operating the blower 21 before the start of water addition.

Second stage One minute after the start of the reaction, the water amount controller 36 was operated to adjust the amount of hot water to 0 ml / min. This state was continued for 2 minutes.

Third stage Thereafter, the water amount controller 36 was operated again to adjust the amount of hot water to 252 ml / min. After adding water for 3 minutes at a warm water volume of 252 ml / min, the water volume was adjusted to 0 ml / min with the water volume controller 36 and the water addition was completed.
The amount of warm water added by the water meter 35 was measured and found to be 948 ml. The time required from the start of water addition to the end of addition was 6 minutes.
30 minutes after the start of the reaction, the valve 19 was closed, and the ejection of the hydrogen phosphide-containing gas from the ejection nozzle 20 was stopped. Further, the nitrogen gas flow rate was adjusted to 0 liter / min with the nitrogen gas flow rate controller 3 almost simultaneously with the closing of the valve 19. Thereafter, the operation of the blower 21 was stopped, and the valves 22 and 23 were closed.
After starting the reaction, the hydrogen phosphide-containing gas was sampled from the sampling port (A) 37 at regular intervals, and the hydrogen phosphide concentration was measured by a predetermined method. The amount of hydrogen phosphide generated per unit time was calculated from the measurement results and shown in FIG. The transition of the amount of hydrogen phosphide generated after the start of the reaction is shown in FIG.
Calculating the flow velocity at the time of ejection from the ejection nozzle 20, since nitrogen gas is flowing at a flow rate of 30 liters / minute from the beginning to the end of the reaction, the amount of nitrogen gas is 30000 ml ÷ the ejection nozzle 20 (inner diameter 20 mm). The cross-sectional area of 3.14 cm ² = 9554 cm, that is, 95.54 m nitrogen gas flows in one minute. When this is converted per second, it becomes 1.59 m / sec. That is, the hydrogen phosphide-containing gas is ejected from the ejection nozzle at a minimum speed of 1.59 m / sec.

(Comparative Example 1)
The same operation as in Example 1 was performed except that water was added to the hydrogen phosphide generation tank all at once without using the heater 5. The temperature of water was 15 ° C. The amount of water added was 948 ml, the same as in Example 1. The time required for water addition was 2 minutes and 35 seconds.
The hydrogen phosphine generation conditions and hydrogen phosphine generation status of Example 1 and Comparative Example 1 are summarized in Table 1, and the amount of hydrogen phosphide generated per unit time is summarized in FIG. According to the present invention, hydrogen phosphide is generated immediately after the addition of water, and the generation amount is gradually increased. The rate of increase is almost the same, and there is no sudden increase in the amount of generation as shown in Comparative Example 1, and it is stable. Moreover, after the generation amount reaches a peak, it gradually decreases, and this point is also different from Comparative Example 1. It can be seen that the fumigation method according to the present invention is more gradual and stable than the conventional method. Therefore, it is possible to easily perform gas injection into a plurality of fumigation chambers by time management. In contrast, in the conventional fumigation method, the temperature of the added water is not affected by the outside air and is not constant, so it is unstable at which timing rapid hydrogen phosphine generation occurs after the start of water addition. It is difficult to put into the room.

(Example 2)
A hydrogen phosphide-containing gas was obtained by the following method using the apparatus shown in FIG.
After putting about 8 liters of water into the water tank 4, when the water supply pump 7 was operated, the three-way valve 8 was operated so that water was circulated to the water tank 4 via the circulation line 9. Subsequently, it heated with the warmer 5 so that the water of the water tank 4 might be 40 degreeC, and the water supply pump 7 was act | operated.
The hydrogen phosphide generation tank 15 having a capacity of about 40 liters was previously heated by the heater 16 until the indicated value of the thermometer 13 reached 40 ° C.

(Process (i))
After the indicated value of the thermometer 13 reaches 40 ° C., 300 g 26 of an aluminum phosphide agent (epifume sold by Ikeda Kogyo Co., Ltd.) is introduced from the inlet 17 and the pressure is adjusted to 0.3 MPa by the pressure regulating valve 2. Then, the flow rate was adjusted to 30 liters / minute with the flow rate controller 3, and nitrogen gas was introduced from the nitrogen gas cylinder 1 into the hydrogen phosphine generation tank 15 through the conduit 10. At this time, the valves 19 and 38 were closed.

(Step (ii))
The pressure in the hydrogen phosphating tank 15 is confirmed with the pressure gauge 14, and nitrogen gas is sealed until the indicated value reaches 0.04 MPa. When the pressure reaches 0.04 MPa, the nitrogen gas sealing is stopped and the valve 19 is opened. The gas was removed and the pressure in the hydrogen phosphide generation tank 15 was returned to atmospheric pressure. The nitrogen gas filling and degassing operations were repeated 5 times.

(Process (iii))
Thereafter, the valve 19 installed in the pipe of the conduit 18 and the valve 30 installed in the distributor 27 are opened, the valve 37 and the valves 28 and 29 installed in the distributor are closed, and nitrogen gas is supplied at 30 liters / minute. As a result of measuring the oxygen concentration in the hydrogen phosphine generating tank 15 from the sampling port (A) with an oxygen concentration meter while introducing it into the hydrogen phosphide generating tank 15 at a flow rate, it was 0.9%.

1st stage It is confirmed by the thermometer 39 that the water temperature of the water tank 4 has reached 40 ° C., the three-way valve 8 is operated, hot water is introduced from the nozzle 12 into the hydrogen phosphide generation tank 15 through the conduit 11, and the reaction is started. did. At this time, the flow rate of the warm water was adjusted to 192 ml / min by the water amount controller 36.
The hydrogen phosphide obtained in the hydrogen phosphine generating tank 15 was mixed with nitrogen gas and other gases and ejected from the ejection nozzle 20 into the fumigation chamber 25 through the conduit 18. The sampling piping valve 40 installed in the fumigation chamber 25 was closed.

Second stage One minute after the start of the reaction, the water amount controller 36 was operated to adjust the amount of hot water to 0 ml / min. This state was continued for 2 minutes.

Third stage Thereafter, the water amount controller 36 was operated again to adjust the amount of hot water to 252 ml / min. After adding water for 3 minutes at a warm water volume of 252 ml / min, the warm water volume was adjusted to 0 ml / min with the water volume controller 36 and the water addition was completed. The amount of warm water added by the water meter 35 was measured and found to be 948 ml. The time required from the start of water addition to the end of water addition was 6 minutes.
After starting the reaction, the hydrogen phosphide-containing gas was sampled from the sampling port (A) 37 at regular intervals, and the hydrogen phosphide concentration was measured by a predetermined method. The amount of hydrogen phosphide generated per unit time was calculated from the measurement results and shown in FIG.

  Gas supply to the fumigation chambers 25, 31, and 32 was carried out by the following method. According to the present invention, the generation of hydrogen phosphide is stable, and the same generation situation is obtained no matter how many times it is repeated. Therefore, it is possible to introduce gas into a plurality of fumigation chambers by time management from the generation amount transition graph. . Since the internal volumes of the fumigation chambers 25, 31, 32 are the same, approximately 56 liters of hydrogen phosphide generated from 300 g of epifume is divided into three equal parts, and 18.7 liters of phosphatization is performed in the fumigation chambers 25, 31, 32, respectively. When the time for supplying hydrogen was determined from FIG. 4 showing the transition of the amount of hydrogen phosphide generated in Example 1, the input time to the fumigation chamber 25 was 8 minutes from the start of the reaction to 8 minutes after the start of the reaction, and input to the fumigation chamber 31. Was found to be 4 minutes from 8 minutes to 12 minutes after the start of the reaction, and 18 minutes from 12 minutes to 30 minutes after the start of the reaction. Therefore, 8 minutes after the start of the reaction, the valve 29 of the distributor 27 was opened and the valve 30 was closed, and the hydrogen phosphide-containing gas was ejected from the ejection nozzle 33 into the fumigation chamber 31. The sampling piping valve 41 was closed. Then, 12 minutes after the start of the reaction, the valve 28 was opened and the valve 29 was closed, and the hydrogen phosphide-containing gas was ejected from the ejection nozzle 34 into the fumigation chamber 32. The sampling piping valve 42 was closed.

30 minutes after the start of the reaction, the valve 28 was closed, and the ejection of the hydrogen phosphide-containing gas was completed. Further, the nitrogen gas flow rate was adjusted to 0 liter / min by the nitrogen gas flow rate controller 3 almost simultaneously with closing the valve 28. Thereafter, the hydrogen phosphide-containing gas in the fumigation chambers 25, 31, 32 is sampled from the sampling port (B) 43, the sampling port (C) 44, and the sampling port (D) 45, respectively, and the hydrogen phosphide concentration is determined by a predetermined method. Was measured.
Table 2 shows the hydrogen phosphide generation conditions and hydrogen phosphine generation conditions of Example 2 and the measurement results of the hydrogen phosphide concentration in the fumigation chambers 25, 31, and 32. The concentration of hydrogen phosphide in the fumigation chambers 25, 31, and 32 was almost the same, and the drug could be administered without any problem in workability.

  The fumigation apparatus and fumigation method of the present invention can be used for fumigation of grain, wood, feed, or live plants that require freshness.

DESCRIPTION OF SYMBOLS 1 Nitrogen gas cylinder 2 Pressure control valve 3 Flow controller 4 Water tank 5 Heater 6 Hot water 7 Pump 8 Three-way valve 9 Circulation line 10 Conduit 11 Conduit 12 Nozzle 13 Thermometer 14 Pressure gauge 15 Hydrogen phosphine generation tank 16 Heater 17 Metal phosphide compound inlet 18 Conduit 19 Valve 20 Jet nozzle 21 Circulating blower 22 Valve 23 Valve 24 Circulating line 25 Fumigation chamber 26 Metal phosphide compound 27 Distributor 28 Valve 29 Valve 30 Valve 31 Fumigation chamber 32 Fumigation chamber 33 Jet nozzle 34 Spout nozzle 35 Water meter 36 Water regulator 37 Sampling port (A)
38 Valve 39 Thermometer 40 Valve 41 Valve 42 Valve 43 Sampling port (B)
44 Sampling port (C)
45 Sampling port (D)

Claims (8)

(I) an inert gas supply means for supplying an inert gas to the hydrogen phosphide generation tank,
(II) Hot water supply means for supplying hot water to the hydrogen phosphide generation tank, and (III) hydrogen phosphide generation means having a hydrogen phosphine generation tank, a conduit and a jet nozzle,
While supplying an inert gas into the hydrogen phosphine generation tank, hot water is supplied to react the metal phosphide compound in the hydrogen phosphide generation tank with the hot water, and the resulting hydrogen phosphide-containing gas is fumigated. A fumigation device that spouts out. The fumigation device according to claim 1, wherein the hot water supply means includes a water tank, a heater, and a pump. The fumigation apparatus according to claim 1, wherein the hydrogen phosphide generating means has a distributor for ejecting a hydrogen phosphide-containing gas to a plurality of fumigation chambers. A method for fumigating a material to be fumigated using the fumigation device according to claim 1,
(I) introducing at least one metal phosphide compound selected from the group consisting of aluminum phosphide and magnesium phosphide into a hydrogen phosphide generation tank;
(Ii) a step of replacing the air in the hydrogen phosphide generation tank and the conduit with an inert gas; and (iii) supplying hot water at 30 to 70 ° C. while supplying the inert gas to the hydrogen phosphine generation tank. Generating a hydrogen fluoride-containing gas and ejecting the obtained hydrogen phosphide-containing gas into the fumigation chamber at a flow rate of 1 m / second or more;
The process of supplying warm water includes the following first to third stages, and the supply amount of warm water in each stage is the following ratio with respect to the total supply amount,
(A) 1st stage 10-40 weight%,
(B) Second stage 0% by weight,
(C) Third stage 60-90% by weight,
The time required for the second stage is 0.5 to 3 times the time required for the first stage.
A fumigation method characterized by that. The fumigation method according to claim 4, wherein the temperature of the hydrogen phosphide generation tank is 30 to 98 ° C. The fumigation method according to claim 4, wherein the hydrogen phosphide-containing gas ejected into the fumigation chamber contains 20 to 99.9% by volume of an inert gas. The fumigation method according to claim 4, wherein the hydrogen phosphide-containing gas is jetted into the gas circulated from the fumigation chamber. The fumigation method according to claim 4, wherein the supply amount of hot water in each stage is 30 to 250 ml / min in the first stage, 0 ml / min in the second stage, and 30 to 360 ml / min in the third stage.

Images