JP6398338B2 - Ammonia storage equipment - Google Patents

Description

  The present invention relates to an ammonia storage facility.

  Conventionally, ammonia storage facilities including storage tanks for storing liquefied ammonia or aqueous ammonia have been installed in factories that use ammonia. In such an ammonia storage facility, for example, as shown in Patent Document 1, in the unlikely event that ammonia leaks, a watering facility for preventing the diffusion of ammonia is installed. Ammonia dissolves quickly in water. For this reason, it can suppress that ammonia is discharge | released in air | atmosphere by sprinkling dilution water with watering equipment and dissolving ammonia in this dilution water.

JP 2001-327978 A

  However, in the conventional method, when ammonia leakage is detected, water is sprayed on the entire storage tank even if the leakage location is local. For this reason, much of the sprinkled water is drained without contact with ammonia. This is equivalent to sprinkling excess dilution water, and wastes industrial water. Also, if a large amount of diluted water is sprinkled, it will take a lot of time to drain the diluted water, which may increase the power consumption due to the operation of the pump, etc. It becomes.

  On the other hand, it is possible to reduce the amount of dilution water used by limiting the watering area. However, since it is not easy for an operator to approach the leaked location, it is difficult to specify the leaked location, and conventionally, it has been difficult to limit the watering area.

  The present invention has been made in view of the above-described problems, and in an ammonia storage facility, if leakage from an ammonia storage tank should occur, the location of ammonia leakage can be identified without performing a confirmation operation by an operator. And it aims at reducing the amount of watering by limiting a watering area further.

  The present invention adopts the following configuration as means for solving the above-described problems.

  The first invention is an ammonia storage facility, wherein the storage tank has a partition wall for storing ammonia and dividing the storage space into a plurality of sections in the horizontal direction, and a plurality of tanks are installed above the storage tank in plan view and A watering nozzle capable of sprinkling water toward the storage tank, a weight measuring unit that is installed in a plurality of locations with respect to the storage tank in a plan view, and that measures the weight of the storage, and based on the measurement result of the weight measuring unit A configuration is adopted in which a leakage portion of ammonia is specified, and a control unit that sprays water from the watering nozzle located above the leakage portion is adopted.

  According to a second aspect of the present invention, in the first aspect of the present invention, a water receiving unit is provided below the storage tank and receives water sprayed from the water spray nozzle, and the water receiving unit defines the water receiving area of the storage tank. A configuration is adopted in which partition walls are defined in accordance with the above-described partitions.

  According to a third invention, in the first or second invention, a configuration is adopted in which the weight measuring unit is installed for each of the compartments provided in the storage tank.

  4th invention is equipped with the ammonia concentration meter installed in the said storage tank in any one of said 1st-3rd invention, The said control part is based on the measurement result of the said ammonia concentration meter, from the said watering nozzle. Adopt a configuration to set the amount of water spray.

  5th invention employ | adopts the structure provided with the drain installed for every said division provided in the said storage tank in the said any one of 1st-4th invention.

  6th invention employ | adopts the structure that the partition of the said storage tank is provided in the clearance gap with respect to the ceiling of the said storage tank in any one of the said 1st-5th invention.

  According to the present invention, the storage space of the storage tank is divided into a plurality of sections by the partition walls. For this reason, when ammonia leaks from any part of the storage tank, the ammonia is reduced in the section connected to the leakage part, the weight balance of the storage tank is lost, and the measurement results of the plurality of weight measuring units are different. Since the way in which the weight balance of the storage tank collapses differs depending on the position of the section where ammonia is reduced, the location of ammonia leakage can be roughly identified from the measurement results of the plurality of weight measuring units. In this invention, a control part specifies the leakage location of ammonia from the measurement result of a some weight measurement part, and limits a watering area based on this specified leakage location. For this reason, the amount of watering as a whole can be reduced. Therefore, according to the present invention, in the case of an ammonia storage facility, in the unlikely event that leakage of ammonia from the storage tank occurs, the location of ammonia leakage is identified and the water spray area is limited without performing confirmation work by an operator. It becomes possible to reduce the amount of watering.

It is a schematic structure figure showing the whole ammonia storage equipment in one embodiment of the present invention. It is a top view which shows typically the positional relationship of the storage tank with which the ammonia storage equipment in one Embodiment of this invention is equipped, a load cell, etc. FIG.

  Hereinafter, an embodiment of an ammonia storage facility according to the present invention will be described with reference to the drawings. In the following drawings, the scale of each member is appropriately changed in order to make each member a recognizable size.

  FIG. 1 is a schematic configuration diagram showing the entire ammonia storage facility 1 of the present embodiment. FIG. 2 is a plan view schematically showing the positional relationship between the storage tank 2 and the load cell 5 provided in the ammonia storage facility 1.

  As shown in FIG. 1, the ammonia storage facility 1 includes a storage tank 2, a pedestal unit 3 (water receiving unit), an ammonia feeding unit 4, a load cell 5 (weight measuring unit), a sprinkling facility 6, and an ammonia concentration. A total 7, an emergency drain pump 8, and a control unit 9 are provided.

  The storage tank 2 includes a container body 2a, legs 2b, and a partition wall 2c. The container body 2a is a pressure container that stores liquefied ammonia. The container body 2a has a substantially cylindrical shape whose axis is horizontal and long in the axial direction, and the inside is an ammonia storage space. The leg 2b is connected to the container body 2a and supports the container body 2a. Two such leg portions 2b are arranged in the axial direction of the container body 2a. In the following description, the axial direction (longitudinal direction) of the container body 2a is referred to as the left-right direction. That is, the leg 2b is provided on each of the right side and the left side of the container body 2a.

  The partition wall 2c is provided inside the container body 2a, and divides the inside of the container body 2a, that is, the ammonia storage space into two compartments in the left-right direction (horizontal direction). In the following description, of these two sections, the left section is referred to as section 2d, and the right section is referred to as section 2e. Moreover, the height of the partition wall 2c is set so that a gap is left with respect to the ceiling of the storage tank 2. For example, the height of the partition wall 2c is 70% with respect to the height of the storage tank 2. By thus forming a gap between the partition wall 2c and the ceiling of the storage tank 2, ammonia is supplied to one of the compartments (the compartment 2d or the compartment 2e), and the other compartment is filled with ammonia. The storage tank 2 can be easily filled with ammonia. Further, when the height of the partition wall 2c is about 70% of the height of the storage tank 2, the impact on the bottom of the storage tank 2 can be suppressed when ammonia flows into the adjacent compartment through the gap. Furthermore, by setting the height of the partition wall 2c to 70% of the height of the storage tank 2, when the ammonia filling rate is about 70% or less, leakage of ammonia can be detected as will be described later. A leak can be found.

  Moreover, the storage tank 2 is provided with the drain 2f provided for every division (division 2d and division 2e). These drains 2f are provided with an on-off valve 2g, and the ammonia stored in the connected compartment is discharged to the outside of the storage tank 2 by opening the on-off valve 2g for inspection or the like.

  The base part 3 is disposed below the storage tank 2 and supports the storage tank 2 from below, and has a drainage pit 3b into which water on the floor board 3a flows below the floor board 3a. Moreover, the base part 3 has the liquid-proof bank 3c so that the storage tank 2 may be enclosed in planar view. A region surrounded by the liquid breakwater 3 c is a water receiving region that receives water sprinkled by the water sprinkling equipment 6 with respect to the storage tank 2. That is, the base part 3 functions as a water receiving part that receives water when water is sprinkled from the watering equipment 6.

  Moreover, the base part 3 is equipped with the partition 3d which partitions a water-receiving area | region according to the division 2d of the storage tank 2, and the division 2e. The partition 3d is provided so as to overlap the partition 2c of the storage tank 2 in a plan view, and divides the water receiving area into two sections in the left-right direction. In the following description, of these two sections, the left section is referred to as section 3e, and the right section is referred to as section 3f. The height of the partition 3d is set to be at least higher than the liquid barrier 3c. The partition wall 3d may be higher than the liquid barrier 3c and may be in contact with or close to the lower surface of the storage tank 2.

  The ammonia feeding part 4 discharges ammonia stored in the storage tank 2 toward an external facility during normal operation. The ammonia 4 is connected to the compartment 2d and the compartment 2e of the storage tank 2, and in the middle of the pipe 4a. And an opening / closing valve 4b whose opening / closing is controlled under the control of the control unit 9, and a liquid feed pump 4c connected to the pipe 4a.

  The load cell 5 is interposed between the leg 2b of the storage tank 2 and the pedestal 3, and measures the weight of the storage tank 2 and outputs the measurement result. Two such load cells 5 are provided by being provided for each leg 2 b of the storage tank 2. That is, in the present embodiment, the load cell 5 is provided at a plurality of locations with respect to the storage tank 2 in a plan view, and is installed for each section (section 2d and section 2e) of the storage tank 2. In the following description, the load cell 5 installed below the compartment 2d of the storage tank 2 is called a load cell 5a, and the load cell 5 installed below the compartment 2e of the storage tank 2 is called a load cell 5b.

  The watering facility 6 includes a plurality of watering nozzles 6a, a control valve 6b provided for each watering nozzle 6a, a pipe 6c for guiding water to each watering nozzle 6a, and an on-off valve 6d provided in the middle of the pipe 6c. It has.

  The watering nozzle 6a is disposed above the storage tank 2, and can be sprinkled by supplying water through the pipe 6c. Such a watering nozzle 6 a sprinkles the supplied water toward the storage tank 2. In the present embodiment, a part of the plurality of watering nozzles 6 a is arranged above the section 2 d of the storage tank 2, and the rest is arranged above the section 2 e of the storage tank 2.

  The control valve 6b adjusts the amount of water supplied to each watering nozzle 6a, and changes the valve opening under the control of the control unit 9. The pipe 6c is a flow path connecting the water source side and each watering nozzle 6a. The open / close valve 6d circulates water to the pipe 6c when opened under the control of the control unit 9, and shuts off the water flow to the pipe 6c when closed.

  The ammonia concentration meter 7 is attached to the storage tank 2, measures the concentration of ammonia stored in the storage tank 2, and outputs the measurement result. The emergency drain pump 8 is connected to the drain pit 3b of the pedestal 3, and pumps the ammonia-dissolved water accumulated in the drain pit 3b to an ammonia abatement facility (not shown) in an emergency, that is, when ammonia leaks.

  The control unit 9 comprehensively controls the operation when ammonia leaks from the storage tank 2, and includes an on-off valve 4 b of the ammonia liquid feeding unit 4, a load cell 5, a control valve 6 b of the sprinkling facility 6, and an on-off valve. 6d and the ammonia concentration meter 7 are electrically connected.

  Such a control unit 9 determines the leakage of ammonia based on the measurement result input from the load cell 5. For example, the control unit 9 determines that ammonia leakage has occurred when the weight of the storage tank 2 has changed beyond the weight change caused by feeding ammonia by the ammonia feeding unit 4.

  Moreover, when the liquid level of ammonia in the storage tank 2 is below the upper end of the partition wall 2c, the ammonia is reduced only in the section connected to the leaked portion. For this reason, the control part 9 compares the measurement result of the load cell 5a and the load cell 5b, and specifies a leak location from this comparison result. For example, when the weight measured by the load cell 5a is smaller than the weight measured by the load cell 5b, it can be determined that leakage has occurred in the section on the side where the load cell 5a is provided, that is, the section 2d side. When the weight measured by the load cell 5b is smaller than the weight measured by the load cell 5a, it can be determined that leakage has occurred in the section on the side where the load cell 5b is provided, that is, the section 2e side.

  Moreover, if the control part 9 specifies the leak location of ammonia, it will sprinkle from the water spray nozzle 6a according to the leak location. For example, when ammonia leaks on the left side section 2d side of the storage tank 2, the control unit 9 opens only the control valve 6b provided in the watering nozzle 6a located above the section 2d, and the section 2e. The control valve 6b provided in the watering nozzle 6a located above is kept closed. Thereby, water is sprayed only on the section 2d side. When ammonia leaks on the right side of the storage tank 2 on the side of the compartment 2e, the control unit 9 opens only the control valve 6b provided in the watering nozzle 6a located above the compartment 2e, and the compartment 2d. The control valve 6b provided in the watering nozzle 6a located above is kept closed. Thereby, water is sprayed only on the section 2e side.

  Further, the concentration of ammonia stored in the storage tank 2 is not necessarily constant. For this reason, when it determines with the ammonia leaking, the control part 9 determines the watering amount from the watering nozzle 6a based on the measurement result of the ammonia concentration meter 7. FIG. Once leakage starts, there is a high possibility that all ammonia in the section (section 2d or section 2e) connected to the leaked part will leak. For this reason, the control unit 9 obtains the amount of ammonia stored in the corresponding section from the measurement result of the load cell 5, further obtains the ammonia concentration from the ammonia concentration meter 7, and can dissolve all the leaked ammonia. Calculate the amount of

  Next, operation | movement when ammonia leaks from the storage tank 2 in the ammonia storage equipment 1 of this embodiment which has such a structure is demonstrated.

  First, when ammonia leaks from the storage tank 2, the measurement result output from the load cell 5 greatly fluctuates. Therefore, the control unit 9 detects this fluctuation and determines that ammonia is leaking. At this time, the control unit 9 closes the on-off valve 4b of the ammonia feeding unit 4 and thereby stops feeding ammonia from the ammonia feeding unit 4.

  Subsequently, the control unit 9 identifies the leak location based on the difference between the measurement result of the load cell 5a and the measurement result of the load cell 5b. Here, the control part 9 specifies whether the leak location is the right side or the left side of the storage tank 2. When the leakage portion is specified in this way, the control unit 9 obtains the necessary water spray amount as described above from the measurement results of the ammonia concentration meter 7 and the load cell 5, and the necessary amount of water spray is generated from the water spray nozzle 6a on the leak portion side. Control valve 6b is controlled as is done. As a result, water is sprayed only from above the leak location.

  The water sprayed from the watering nozzle 6a passes through the leaked portion and flows to the base portion 3 that functions as a water receiving portion. At this time, the leaked ammonia is dissolved in water. In addition, ammonia that has flowed out without being dissolved in water immediately after leaking from the storage tank 2 also flows into the section (section 3e or section 3f) surrounded by the breakwater 3c and the partition wall 2c, and here or in the drain pit 3b, Dissolves in water that pours down from above or water that has been stored earlier. Then, the ammonia-dissolved water stored in the drain pit 3b is sent to the ammonia abatement facility by the emergency drain pump 8.

  In the ammonia storage facility 1 of the present embodiment as described above, the storage space of the storage tank 2 is divided into a plurality of sections (section 2d and section 2e) by the partition wall 2c. For this reason, if ammonia leaks from any part of the storage tank 2, the ammonia is reduced in the section (section 2d or section 2e) connected to the leaked place, the weight balance of the storage tank 2 is lost, and the load cell 5a and the load cell 5b are measured. There will be a difference in the results. The control part 9 specifies the ammonia leak location from the difference between the measurement results, and limits the water spray area based on the specified leak location. For this reason, the amount of watering as a whole can be reduced. Therefore, according to the ammonia storage facility 1 of the present embodiment, in the unlikely event that a leakage of ammonia from the storage tank 2 occurs, the location of ammonia leakage is identified without performing a confirmation operation by an operator, and the watering area is further defined. It becomes possible to reduce the amount of watering by limiting.

  Moreover, in the ammonia storage equipment 1 of this embodiment, it is provided with the base part 3 which functions as a water receiving part which receives the water sprinkled from the watering nozzle 6a, and this base part 3 divides the water receiving area into the compartment ( It has the partition 3d divided according to the division 2d and the division 2e). For this reason, it is possible to prevent the leaked ammonia from spreading beyond the watering area in the water receiving region, and to reliably dissolve all ammonia in water.

  Moreover, in the ammonia storage facility 1 of the present embodiment, the load cell 5 is installed for each section (section 2d and section 2e) of the storage tank 2. For this reason, it is possible to accurately acquire a change in weight balance for each section (section 2d and section 2e). However, even when two load cells 5 are installed in one section, it is possible to acquire a change in weight balance.

  Moreover, in the ammonia storage equipment 1 of this embodiment, the control part 9 sets the watering amount of the watering nozzle 6a based on the ammonia concentration meter 7 measurement result. For this reason, it is possible to prevent water from being sprayed more than necessary, regardless of the concentration of ammonia stored in the storage tank 2.

  Moreover, in the ammonia storage facility 1 of the present embodiment, a drain 2f is installed for each section (section 2d and section 2e) of the storage tank 2. For this reason, ammonia remaining in the compartment where no leakage occurs can be easily extracted from the storage tank 2 and effectively used.

  Further, in the ammonia storage facility 1 of the present embodiment, the partition wall 2 c of the storage tank 2 is provided with a gap with respect to the ceiling of the storage tank 2. For this reason, when supplying ammonia to the storage tank 2, by making the liquid level of ammonia higher than that of the partition wall 2c, ammonia can be easily supplied to all the sections (section 2d and section 2e).

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the said embodiment. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the spirit of the present invention.

  For example, in the above embodiment, the configuration for measuring the weight of the storage tank 2 using the load cell 5 has been described. However, this invention is not limited to this, You may measure the weight of the storage tank 2 using another weight measurement part.

  Moreover, in the said embodiment, the structure which divides the inside of the storage tank 2 into two was demonstrated. However, the present invention is not limited to this, and a larger number of the interiors of the storage tank 2 may be partitioned by partition walls. For example, it is possible to adopt a configuration in which the inside of the storage tank 2 is divided into four by a cross-shaped partition wall.

  DESCRIPTION OF SYMBOLS 1 ... Ammonia storage equipment, 2 ... Storage tank, 2a ... Container main body, 2b ... Leg part, 2c ... Partition, 2d ... Compartment, 2e ... Compartment, 2f ... Drain, 2g ... On-off valve, 3 ... Stand, 3a ... Floor plate, 3b ... Drainage pit, 3c ... Breakwater, 3d ... Bulkhead, 3e ... Section, 3f ... Section, 4 ... Ammonia liquid feeding section, 4a ... Piping, 4b ... Open / close valve, 4c ... Feed pump, 5 ... Load cell, 5a ... Load cell, 5b ... Load cell, 6 ... Watering equipment, 6a ... Watering nozzle, 6b ... Control valve, 6c ... ... Piping, 6d ... Open / close valve, 7 ... Ammonia concentration meter, 8 ... Emergency drain pump, 9 ... Control unit

Claims (5)

A storage tank having a partition wall for storing ammonia and dividing the storage space into a plurality of sections in the horizontal direction;
A plurality of water spray nozzles installed in plan view above the storage tank and capable of sprinkling water toward the storage tank,
A weight measuring unit that is installed in a plurality of locations with respect to the storage tank in plan view and measures the weight of the storage,
The ammonia leakage point is specified based on the measurement result of the weight measurement unit, and includes a control unit that sprinkles water from the watering nozzle located above the leakage point .
The ammonia storage facility , wherein the weight measuring unit is installed for each of the compartments provided in the storage tank . A water receiving portion is provided below the storage tank and receives water sprayed from the water spray nozzle, and the water receiving portion includes a partition that partitions the water receiving area according to the partition of the storage tank. The ammonia storage facility according to claim 1. An ammonia concentration meter installed in the storage tank,
Wherein the control unit, the ammonia storage facility according to claim 1 or 2, wherein the setting the watering amount from the water spray nozzle on the basis of the measurement result of the ammonia concentration meter. The ammonia storage facility according to any one of claims 1 to 3 , further comprising a drain installed for each of the compartments provided in the storage tank. The ammonia storage facility according to any one of claims 1 to 4 , wherein the partition wall of the storage tank is provided with a gap with respect to the ceiling of the storage tank.

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