JPH03277224A - Fumigation silo and operation thereof - Google Patents

Abstract

PURPOSE:To provide the title silo easy to fill fumigating gas therein and resistant to fumigation leakage in the radial direction, so designed that intermediate pipings are opened in a space between the respective outer surfaces of hollow standing truncated conical guide cones fixed at the intermediate section within the silo main body and the inner surface of said silo main body. CONSTITUTION:When the silo main body 20 is to be charged with e.g. a feed 23, the feed 23 is introduced through intermediate pipings 2-7 located in the space between the guide cones 25 and the inner surface of the main body 20. Therefore, the load of the feed does act on the guide cones 25; that is, since part of such load is supported by the guide cone 25, each feed is subjected to only part of the own weight of the feed 23 on and above-said feed; thereby, mitigating vertical densification of the feed 23, leading to smooth passage of a fumigating gas and reducing radial deviation of the grain size of the feed, thus doing away with fumigation leakage.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a fumigation silo and a method of operating the same.

[Prior art and problems to be solved by the invention]
As a fumigation silo for fumigating pests lurking in stored materials such as food and grain, conventionally, silos with pipes opened at the bottom and top of the silo body have been used.

In this smoked grass silo, after feeding the feed into the silo,
Even if you attempt to fill the entire area of the silo with fumigation gas by discharging fumigation gas from the bottom piping and suctioning it from the top piping, the weight of the feed will densify the feed at the bottom of the silo, resulting in a large pressure loss. 4' There was a problem that the sg gas was not sufficiently circulated, and therefore the entire area of the silo could not be sufficiently filled with fumigation residue.6 On the other hand, a blower with a high discharge pressure was used to circulate the fumigation gas. However, there was a problem in that the strength of the silo body and piping had to be strengthened, and the costs of the silo body, piping, blower, etc. were rising.

In addition, when feed is put into the conventional fumigation silo, coarse feed has small corners, so the radius of the silo is 11.
7 Uneven distribution 1 Due to the short length of the feed, the LLH is unevenly distributed in the center in the radial direction.As a result, even if the feed is fumigated, the fumigation gas will only pass through the feed in the periphery of the silo and will not reach the center of the silo. Another problem was that the feed portion could not be sufficiently fumigated.

Due to these problems, conventional silos can fumigate particulate feed such as corn by filling it with fumigation gas such as methyl bromide, but cannot fumigate powdered feed such as soybean meal. Unable to use the same method, hostoxin tablets are mixed into the feed - their decomposition causes fumigation of the feed.

However, this method had problems such as requiring a long time for fumigation, temperature restrictions, and tablet residue, so fumigation using fumigation gas was proposed based on the request of 8.2. Is this the reduced pressure silo disclosed in Japanese Patent Publication No. 578588?

This method requires the process of evacuating the silo prior to the process of filling it with fumigation gas, so looking only at the process of filling it with fumigation gas, the permeation of fumigation gas into the feed becomes faster. On the contrary, the overall process is becoming more complicated. Furthermore, since fumigation gas is generally adjusted to a constant concentration by vaporizing the liquefied fumigant and then mixing it with air, it does not seem to be meaningful to initially reduce the pressure and exhaust the air.

In addition, a method has been proposed for destroying feed bridges by vacuum breaking the vacuum silo, but it would be time-consuming and labor-intensive to seal the silo and evacuate the entire silo every time a bridge occurs. Not practical 6 Furthermore, it is actually quite difficult to break a large volume of vacuum in a short enough time to apply a shock.In other words, if the vacuum is broken with a small diameter valve, the pressure will slowly increase. It is mechanically difficult to open a large-diameter valve (for example, the shutter of a feed outlet) instantly.

In view of the above problems, it is an object of the present invention to provide a fumigation silo that allows the silo to be easily filled with fumigation gas and that is less likely to cause fumigation leakage in the radial direction, and to provide a method for operating the fumigation silo. purpose.

[Means for Solving the Problems] The present invention comprises a fumigation silo in multiple stages in the height direction, a guide cone in the shape of a hollow inverted truncated cone is fixed to each stage, and the outer surface of the guide cone and the silo body are connected to each other. The above objective was achieved by opening the intermediate piping into the gap between the inner surface and the inner surface, and based on this mechanical configuration, the flexibility of the fumigation silo operating method was greatly increased as shown below. The above objective was achieved by increasing the efficiency of the project.

[Example] Examples of the present invention will be described below with reference to the drawings.6 Fig. 1 is a schematic longitudinal cross-sectional view showing a first example of the present invention. A feed inlet 21 is formed at the top of the main body 20, and a top pipe 8 is opened. Further, a feed outlet 22 is formed at the bottom of the silo main body 20, and the bottom pipe 1 covered with an inlet cover is opened at the upper part of the opening.

Six guide cones 25 are installed inside the silo body 20, and each guide cone 25 is formed in the shape of a hollow inverted a-head cone. Fixed. A ring-shaped circular tube 26 having an opening around the entire circumference is fixed in the gap between the outer surface of each guide cone 25 and the inner surface of the silo body 20. Each of the six circular pipes 26 protected by the cone 25 has, in order from the bottom, an intermediate pipe 2, an intermediate pipe 3, and a pipe 2, which penetrate the side wall of the silo body 20. 6 to which the intermediate piping 7 is connected, the bottom piping 1, the intermediate piping 2 to 7, and the top piping 8 are connected to the discharge header A via valves IA to 8A, respectively,
It is also connected to the discharge header B via valves IB to 8B. The discharge header A has a valve 1 at the discharge port of the blower 30.
0, and is connected via a valve 13 to a pressure accumulation tank 36 in which pressure is accumulated by a compressor 35. The discharge header B has a valve 11 at the intake port of the blower 30.
A fumigation gas supply device 31 is connected to the discharge port of the 610-warmer 30 which is connected to the atmosphere through the valve 14 and communicates with the atmosphere through the valve 14.
is connected to the air via valve 15, and the inlet of the blower 30 communicates with the atmosphere via valve 12.
, IB: 2A, 2B.

. . .: 8A and 8B may each be configured with a three-way switching valve7. The present embodiment is configured as described above, and the operation of this fumigation silo will be described below. The operating modes of a fumigation silo can be broadly divided into feeding, filling with fumigation gas,
There are five operating modes: fumigation, fumigation gas discharge, and feed dispensing. Among these, the fumigation mode is a mode in which the silo is simply opened at a predetermined time after filling the silo with base gas.
Since the operation mode of 4N is simply fumigated by leaving it for a long time), we will discuss the other 4N operation modes.6 First, in the feed input mode, the input port 2 of the silo body 20
1, the feed 23 is introduced. Since this embodiment is constructed as described above, the following two effects can be obtained when feeding the feed.

The first is to reduce the densification of the feed 23 in the height direction. When the structure of a conventional silo is uniform in the height direction, the weight of the feed above it acts on the feed at each height, so the feed becomes more dense toward the bottom. occurs significantly. In contrast, in this embodiment, a guide cone 25 is introduced, and the load of the feed necessarily acts on the guide cone. In other words, since a portion of the load of each feed is supported by the guide cone, only a portion of the weight of the feed above it acts on each feed, thus reducing the densification of the feed in the height direction. Ru.

Second, normally when feed is put into a silo, coarse feed is unevenly distributed in the radial periphery of the silo due to its small angle of repose, while fine feed is unevenly distributed in the radial center of the silo due to its large angle of repose. However, the guide cone 25 acts in a direction to neutralize this grain size (14).In other words, since the slope of the guide cone is inclined toward the center of the silo, the slope of the guide cone Of the feed that falls during transfer, coarse particles tend to reach further away, near the center of the silo, and fine particles tend to remain at the periphery of the silo, resulting in a reduction in uneven distribution of particle size in the radial direction as a whole. Ru.

As described above, since the densification of the feed is reduced in the height direction, the passage of fumigation gas is improved, and in the radial direction, uneven distribution of particle sizes is reduced, so fumigation leakage can be eliminated.

In the above explanation, the blower 30 was not used when feeding feed, but even better effects can be obtained by operating the blower 30. That is, as shown in Table 1, first, valve 12.10 and LA are opened, blower 30 is operated, and feed is introduced while discharging air from bottom pipe 1.
Next, when it is confirmed by a level switch (not shown) installed in the silo that the feed has accumulated near the guide cone 25 at the bottom of the grain, the valve IA is closed and the valve 2A is opened to discharge air from the intermediate piping 2. After feeding the feed, air is sequentially discharged from the upper pipe according to the height of the feed placed in the silo.Finally, the valve 7A is opened and air is discharged from the middle pipe 7 while the silo is closed. Add feed to the top.

According to such an operating method, air is sequentially discharged from the pipes 1 to 7 and is discharged from the feed inlet 21, that is, an upward air current is always generated as a whole, and the feed is introduced into this upward air flow. Since the feed is fluffed in the height direction and does not become dense, it is also randomly deposited in the radial direction, so uneven distribution of grain size can be almost completely prevented. Regarding the detection of the height of the feed, a level transmitter may be used instead of the level switch to take out the analog FZ No. 1 and 2 tables, and the response may be opened and closed in accordance with the signal.

In addition, regarding the discharge of air, instead of the inlet 21, it can be discharged to the atmosphere from the top pipe 8 through the valve 14, or it can be sucked from the top pipe 8 and used with a filter through a blower 30. It can also be circulated. Furthermore, air in the pressure accumulating tank 236 can be used instead of the blower 30.

Next, after feeding the feed as described above, the feed inlet 21 is sealed and the mode shifts to fumigation gas filling mode, but in this embodiment, as described above, the densification of the feed and the uneven distribution of particle sizes are reduced. In addition, if the feed is added while operating the blower, the densification of the feed and uneven distribution of particle sizes will be further reduced, so fumigation gas can be discharged from the bottom pipe 1 as in the conventional method. Even if the air is sucked through the top pipe 8 and circulated, the load on the blower will not become excessive and fumigation leakage will be reduced.

However, when fumigating the feed after a long period of incubation, it is possible that the feed becomes densified. In this case, it is best to fluidize the feed prior to fumigation to improve the passage of the fumigation gas as follows. That is, as shown in Table 2, valves 7A, 8B, and 14 are opened, and valve 13 is opened to form a flow path for discharging from intermediate piping 7 and discharging from top piping 8.
The fluidization of the feed can be achieved by sequentially moving the 6 or less discharge piping that spouts out the air inside to the lower piping and jetting out the air inside the pressure accumulating tank 36.

As mentioned above, before a long period of time has passed after feed is added,
Alternatively, if a long period of time has elapsed, if the feed is fluidized and then filled with fumigation gas, the blower can be The load will not be excessive. However, in this embodiment, since there are intermediate pipes 2 to 7, it is more preferable to utilize these and use the following method.

That is, as shown in Table 3, first, valves 10, 11 and 1
5 is opened, the blower 30 is operated, and valves IA and 2B are opened to form a flow path for discharging fumigation gas from the bottom pipe 1 and suctioning it from the middle pipe 2. Circulate the gas. Next, the valves 1A and 2B are closed, and the valves 2A and 3B are opened to form a flow path from the intermediate pipe 2 to the intermediate pipe 3, and the fumigation gas is circulated for a predetermined period of time. Thereafter, the fumigation gas is similarly circulated in each section divided in the height direction of the silo, so that the entire area of the silo is filled with fumigation gas.

According to this method, firstly, the load on the blower is reduced only in the sections of Tables 3 and 4 divided in the height direction, so the load on the blower is significantly reduced.

Second, when discharging from the bottom piping 1 and suctioning from the top piping 8 as in the past, the fumigation gas flows randomly at the bottom of the silo immediately after discharge and at the top immediately before suction, so that the fumigation gas flows in a radial direction. However, in the middle part of the silo, the influence between the bottom and the top is not transmitted, so fumigation leakage is likely to occur even if there is a slight uneven distribution of particle size.

However, in this example, since the distance between the discharge piping and the suction piping is significantly narrowed, the flow in the area where the fumigation gas circulates remains random, so there is some uneven distribution of particle size. Fumigation leaks are also less likely to occur.

In addition, in Table 3, the fumigation section is raised sequentially, but this is sequentially lowered, that is, step 7, step 6,
・・・・・・It is also possible to fill the fumigation gas in the order of step 1. Also, in Table 3, A is discharged from the lower piping and sucked from the upper piping. Polyphonic 1 It is also possible to discharge from one pipe and suction from a lower pipe.

In Table 3, the discharge piping and the suction piping are adjacent to each other, but when this type of operation is used, the fumigation gas does not pass through the center of the silo, but instead takes a short cut around the silo, causing fumigation leakage into the center of the silo. may occur. If such a risk is a concern, it can be dealt with by adjusting the amount of filtration of the blower, but more simply, it is preferable to circulate the fluid one step at a time, as shown in Table 4. However, in Table 4, only the channels to be formed are shown, and the valves to be opened are omitted. In addition, in Table 4, pure one-step circulation is from process 2 to process 7, and J process 1
Step 8 is a connecting process to ensure fumigation at the bottom of the silo, and Step 8 is a connecting process to ensure final fumigation at the top of the silo.

As a matter of course, when the number of intermediate pipes is one, the circulation that skips one stage means the circulation from the bottom pipe to the top pipe, which is the same as a conventional filling method. Therefore, for one-step circulation in the method of the present invention, it is necessary to have a plurality of intermediate pipes. Also, as in the case of Table 3, the order of the steps in Table 4 can be reversed and filled in the order of step 8, step 7, ..., step 1, or it can be filled in the order of step 8, step 7, etc. The above cycle is also possible.

When using the fumigation gas filling method shown in Table 3 or Table 4 as shown above, the filling section is short, so the load on the blower is reduced and fumigation leakage is less likely to occur. It is also possible to fumigate several zones at the same time if there is sufficient load capacity. Among these methods of simultaneously filling multiple sections with fumigation gas,
Tables 5 and 6 show examples where the discharge piping and suction piping are adjacent to each other, and Table 7 shows examples where the discharge piping and suction piping are basically one step apart. When such a filling method is used, it is possible to shorten the filling time with fumigation gas.

Next, after filling the entire area of the silo with fumigation gas,
Fumigation is carried out for a predetermined period of time, and then the fumigation residue is discharged. This fumigation gas discharge mode should be given the same consideration as the Pi vapor gas filling mode, taking into account the reduction of the blower load and the reduction of fumigation gas discharge leakage, and therefore the valve 10.11 and 15 instead of opening valves 12.10 and 14, the third
It is preferable to operate the valves as shown in Table 7.

After finally discharging the fumigation gas, feed f423 is discharged if necessary. As described above, in this embodiment, the density of the feed t4 in the height direction is reduced in the feeding mode of feed [1], so the situation where a bridge is formed when discharging RFl is originally reduced. . When a long period of time has passed after fumigation, it is preferable to fluidize the feed according to Table 2 before discharging the feed. After that, if a bridge is formed during feed dispensing and the feed cannot be dispensed, it is preferable to destroy the bridge in the following manner by utilizing the intermediate pipes 2 to 7.

That is, as shown in Table 8, the valve 13 is opened, and the valve IA is opened to cause the accumulated air in the tank 36 to be blown out from the bottom pipe, and then sequentially to be blown out from the intermediate pipes 2 to 7. , f&, air is blown out from the top pipe 8. However, the order of ejection does not necessarily have to be from the lower piping to the -L piping; it may be the reverse, or it may be in a completely random order. In addition, when the bridge is destroyed and feed dispensing is resumed, it is not necessary to continue with the subsequent process.In addition to the destruction of the bridge, it is necessary to detect the occurrence of the feed by using a detection means such as a health switch. It is also possible to detect the height of the feed and blow out air from a pipe corresponding to the height to destroy the bridge.

Table 8 Also, in this embodiment, the pressure accumulator tank 36 is connected to the discharge header A, but this is connected to the discharge header B, and the valve l
It is also possible to open valves IB to 8B in place of A to 8A.6 Next, FIG. A conical second guide cone 28 is fixed to the lower part of the lowermost guide cone, the upper part of the uppermost guide cone, and the space between each guide cone.

As mentioned above, in the conventional silo, coarse particles are unevenly distributed around the radial direction of the silo, and in order to neutralize this, the guide cone 25 is introduced in the first embodiment, but only the guide cone is used. If used, there is a risk that excessive neutralization will occur, that is, coarse particles will be excessively concentrated in the center of the silo, causing the particle size to become unevenly distributed again. When such a possibility is a concern, as in this embodiment, the second guide cone 2
8 is preferably introduced to redistribute the particle size.

Also, is the guide cone 25 effective in reducing feed densification in the radial peripheral area?
8 acts to prevent the feed from becoming denser in the center, so the structure of the second embodiment almost completely prevents the feed from becoming denser in the height direction. The preferred operating method of this second embodiment is the same as that of the first embodiment.6 [Effects of the Invention] Since the fumigation silo according to the present invention has a kite cone,
The densification of feed in the height direction and uneven distribution of particle size in the radial direction are reduced, and therefore, in addition to granular feed such as corn, powdered feed such as soybean meal can also be processed using the fumigated silo according to the present invention. Fumigation can be carried out using fumigating gas such as methyl bromide.

Furthermore, since the present invention has an intermediate pipe in addition to the bottom pipe and the top pipe, the flexibility of each operation mode of feeding feed, filling fumigation gas, discharging fumigation scum, and discharging feed can be dramatically increased. I was able to increase 6

[Brief explanation of drawings]

FIG. 1 is a schematic vertical sectional view of a first embodiment of the present invention, and FIG. 2 is a schematic reduced sectional view of a second embodiment Q.

Claims (11)

[Claims] (1) Bottom piping and top piping are opened at the bottom and top of the silo body, respectively, and a guide cone shaped like a hollow inverted truncated cone is fixed to the middle part of the silo body, and each outer surface of the guide cone is fixed to the middle part of the silo body. A fumigation silo with intermediate piping opened in the gap between the inner surface of the silo body and the inner surface of the silo body. (2) The intermediate piping includes a ring-shaped piping with an opening fixed in the gap between the outer surface of the guide cone and the inner surface of the silo body, and another piping that is connected to the piping and passes through the silo body. 2. The fumigation silo according to claim 1, comprising: piping. (3) A conical second guide cone is fixed to at least one of the lower part of the lowermost guide cone, the upper part of the uppermost guide cone, and between each guide cone. The fumigation silo according to 1 or 2. (4) A method for charging stored material into a fumigation silo according to claim 1, 2, or 3, comprising: discharging air from one of the pipes, and connecting the pipe for discharging the air to the stored material that has been introduced into the silo body. A method of operating a fumigation silo in which stored material is transferred to the upper pipes in sequence according to the height of the pipe. (5) A method for fluidizing the accumulated material put into the fumigation silo according to claim 1, 2 or 3, which comprises blowing out the accumulated air from one of the piping and discharging it from the top piping, and A method of operating a fumigation silo that fluidizes the accumulated material by sequentially moving the piping that spews out water to the lower piping. (6) A method for filling the fumigation silo with fumigation gas according to claim 1, 2 or 3, comprising: discharging fumigation gas from one of the pipes, and discharging the fumigation gas from a pipe located above the one pipe. A method of operating a fumigation silo, in which the entire area of the silo body is filled with fumigation gas by circulating fumigation gas by suctioning the gas, and sequentially moving at least one of the discharge piping and the suction piping. (7) A method for filling the fumigation silo with fumigation gas according to claim 1, 2 or 3, wherein the fumigation gas is discharged simultaneously from a plurality of the pipes that are not adjacent to each other, and the fumigation gas is discharged between each discharge pipe and at the top. The fumigation gas is circulated by suctioning fumigation gas simultaneously from the same number of pipes as the plurality of pipes located at the top of the pipes, and at least one of the discharge pipes and suction pipes is sequentially transferred to the silo main body. How to operate a fumigation silo that fills the entire area with fumigation gas. (8) A method for discharging fumigation gas from a fumigation silo according to claim 1, 2 or 3, comprising discharging air from one of the pipes and discharging fumigation gas from a pipe located above the one pipe. A method for operating a fumigation silo, in which fumigation gas is discharged from the entire area of the silo body by sequentially moving at least one of the discharge piping and the discharge piping. (9) A method for discharging fumigation gas from a fumigation silo according to claim 1, 2, or 3, comprising simultaneously discharging air from a plurality of pipes that are not adjacent to each other, and discharging air between each discharge pipe and the top discharge pipe. Fumigation in which fumigation gas is simultaneously discharged from the same number of pipes as the plurality of pipes located at the top of the silo, and at least one of the discharge pipes and discharge pipes is sequentially transferred to discharge the fumigation gas from the entire area of the silo body. How to operate a silo. (10) A method for destroying a bridge of accumulated material in a fumigation silo according to claim 1, 2 or 3, wherein the accumulated air is ejected from one of the pipes, and the pipes ejecting the air are sequentially transferred. How to operate a fumigation silo to destroy the storage bridge. (11) A method for destroying a bridge of accumulated material in a fumigation silo according to claim 1, 2 or 3, wherein the accumulated air is blown out from the pipe corresponding to the height of the accumulated material that has caused the bridge. How to operate a fumigation silo to destroy the storage bridge.