JP2019095029A - Gas supply device and gas supply method - Google Patents

Abstract

To reduce troublesomeness of work performed by a maintenance person and reduce a risk of a stop of gas supply as a whole.SOLUTION: A liquefied gas supply source 11a includes: a gas container 111a filled with liquefied gas; a pressure-reducing valve 112a for controlling a gas supply amount from the gas container 111a to a consumption facility 100; and a weight detector 113a for substantially measuring a residual amount of the liquefied gas remaining in the gas container 111a by measuring a weight of the gas container 111a. Also, a liquefied gas supply source 11b has the same configuration. In accordance with procedures in a flow chart, a control section 21A controls an opening/closing degree of each of the pressure-reducing valve 112a and a pressure-reducing valve 112b, on the basis of the weight measured by each of the weight detector 113a and a weight detector 113b. Thus, a gas consumption rate of the liquefied gas supply source 11a and a gas consumption rate of the liquefied gas supply source 11b can be made substantially equal to each other.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gas supply apparatus and a gas supply method.

  In a system for supplying gas to customers (consumer equipment), instead of connecting a plurality of gas containers as one (one) supply source, a plurality of gas supply sources (cylinder cabinets etc.) ) (Multiple points) By connecting to the consumption equipment in parallel as it makes possible to increase the supplyable amount, and because there are multiple control systems and piping systems according to the number of parallels, Even if a failure occurs and the system can not be supplied, the other systems compensate for the failure as a whole to make it resistant to the risk of failure. This is employed in both liquefied gas and compressed gas supply devices.

  FIG. 6 (a) shows an example where there are two gas supply sources. Specifically, two of the gas supply source 101a and the gas supply source 101b are connected in parallel to the consumption facility 100. Here, the gas supply source 101a includes a gas container 1011a and a pressure reducing valve 1012a, and the gas supply source 101b includes a gas container 1011b and a pressure reducing valve 1012b. In addition, although the case where the number of consumption facilities is one is shown in this example, there are also cases where gas is supplied to a plurality of consumption facilities from a plurality of gas supply sources (many to many).

  However, in the above-described prior art, even if each supply pressure is initially set identically by each pressure reducing valve in anticipation of supplying gas from each gas supply source equally, consumption equipment from each gas supply source Due to the difference in the distance to the point, etc., even when the supply pressure is set, the gas changes little by little with the gas consumption. Therefore, the supply pressure will be gradually different in each gas supply source, and in such a situation, the gas supply amount from the gas supply source having a relatively higher supply pressure than the gas supply source having a low supply pressure As a result, a so-called "one-stream" state occurs (Fig. 6 (b)). In other words, the load may be biased to a particular gas source.

  In such a case, the cycle of container replacement is different for each gas supply source, and the work of replacement maintenance becomes complicated. On the other hand, in order to avoid the risk of stopping the gas supply, even if the gas amounts of the respective gas supply sources are initially set to be different so as to shift the time of container replacement at each gas supply source, There is also a possibility that a situation may occur in which the supply of gas is stopped.

  In order to cope with such a situation, it is necessary for the operator to grasp the remaining amount of gas of each gas supply source and the transition of gas consumption and to adjust the pressure reducing valve one by one, which often causes a burden on facility management.

  Here, there is a technology disclosed in Patent Document 1 as a technology capable of partially solving the above-mentioned problems. In the technique disclosed in the document, the gas supply valve associated with the gas container with the smallest remaining amount of gas is closed or opened so that the residual amount difference is always within a predetermined range for a plurality of gas containers. I have control.

Patent No. 5111962 gazette Patent No. 5722186 gazette Patent No. 5792608

  According to the technique of Patent Document 1, the replacement period is the same for each gas container, and the remaining amount difference is controlled within the predetermined range, so the problem caused by the proposal of the technique of the document, ie, At the time of replacement, the problem that the remaining amount is different among the gas containers and the gas is wasted (the first half of paragraph [0005]) can be solved.

  However, in Patent Document 1, although the gas supply from the gas container with the smallest remaining amount of gas is intermittently “stopped”, it is assumed that the supply from the remaining gas containers is interrupted due to a failure. For example, the risk of stopping the gas supply will increase.

  Moreover, in Patent Document 1, when replacing the gas container, all replacement is strictly required (the latter half of paragraph [0003] and [0005]), and therefore, the "remaining amount difference" is controlled within a predetermined range. ing. Therefore, in patent document 1, in the case of replacement | maintenance maintenance, the subject that the time which can not be supplied with gas inevitably is made occurs.

  Patent Document 2 discloses the following technical contents. That is, in the case of a liquefied gas having a low vapor pressure near normal temperature such as liquefied ammonia, the amount of evaporation gradually decreases when the remaining amount of gas becomes 30% or less of the volume of the gas container, and the flow rate required of the gas use destination Because it becomes difficult to supply the gas, when the remaining amount of gas reaches about 30% of the container volume, the gas container for supplying the gas is switched to replace the liquefied gas container in which the remaining amount of liquefied gas is reduced However, in order to solve such problems, when switching from an old gas container to a new gas container, it is necessary to provide time for both supplies to be supplied redundantly so that all the gas in the old gas container is used up, We are working to improve the efficiency. Moreover, patent document 3 is the improvement technique.

  The present invention has been made in view of the above circumstances, and can reduce the complexity of work of maintenance personnel and can reduce the risk that the gas supply as a whole will stop as a whole. It is to provide a supply method.

In order to solve the above-mentioned subject, the present invention comprises the following composition.
[1] Two or more gas supply sources connected in parallel to a facility to be supplied with gas via piping and capable of simultaneously supplying gas,
A control unit configured to control a gas supply pressure to the equipment of each of two or more of the gas supply sources;
The control unit controls each gas supply pressure so that the gas consumption rate of each of the two or more gas supply sources is substantially the same.
[2] The gas supply device according to claim 1, wherein the control unit controls each gas supply pressure such that a difference in gas consumption of each of the two or more gas supply sources falls within a predetermined range.
[3] The control unit
Initially, a first set supply pressure is set as the gas supply pressure for all two or more of the gas supply sources,
The gas supply pressure relative to the gas supply source at which the difference in gas consumption has reached a first predetermined value as compared to the gas supply source having the smallest gas consumption rate of the two or more gas supply sources. Setting a second set supply pressure lower than the first set supply pressure,
3. The gas supply device according to claim 2, wherein the gas supply pressure is returned to the first set supply pressure when the difference in gas consumption reaches a second predetermined value.
[4] Gas supply to the equipment of two or more gas sources connected in parallel to the equipment to be supplied with gas and capable of simultaneously supplying gas, and each of the two or more gas sources A control unit configured to control a pressure;
The control method controls each gas supply pressure such that the gas consumption rate of each of the two or more gas supply sources is substantially the same.

  According to the gas supply apparatus and the gas supply method of the present invention, it is possible to eliminate the complexity of the maintenance plan and the maintenance work of the replacement maintenance personnel, and to minimize the situation where the gas supply to the consumption facility is stopped.

FIG. 1 is a diagram for explaining an embodiment in the case where the gas to be supplied is based on liquefied gas, (a) is a configuration diagram of the gas supply device, and (b) is an operation of its control unit It is a flowchart which shows a process. FIG. 2 is a diagram for explaining an embodiment in the case where the gas to be supplied is based on compressed gas, (a) is a configuration diagram of the gas supply device, and (b) is an operation of its control unit It is a flowchart which shows a process. FIG. 3 is a block diagram of a gas supply apparatus according to a detailed embodiment. FIG. 4 is a graph showing the temporal transition of the residual gas pressure P and the like. FIG. 5 is a table showing specific numerical values and the like along the temporal flow. FIG. 6 is a diagram for explaining the prior art.

  Hereinafter, the configuration of the gas supply apparatus, which is an embodiment to which the present invention is applied, will be described in detail with reference to the drawings, together with a gas supply method using the gas supply apparatus. In the drawings used in the following description, in order to make the features easy to understand, the features that are the features may be enlarged for the sake of convenience, and the dimensional ratio of each component may be limited to the same as the actual Absent.

1 and 2 are views for explaining an embodiment of the gas supply apparatus and the gas supply method of the present invention.
First, FIG. 1 is a diagram for explaining an embodiment in the case where the gas to be supplied is a liquefied gas, and FIG. 1 (a) is a configuration diagram of the gas supply device, and FIG. 6 is a flowchart showing operation processing of the control unit.

  As shown to Fig.1 (a), 1 A of gas supply apparatuses are provided with the liquefied gas supply source 11a and the liquefied gas supply source 11b which were piping-connected in parallel with the consumption installation 100, and the control part 21A. Here, the liquefied gas supply source 11a includes a gas container 111a filled with liquefied gas, a pressure reducing valve 112a for controlling a gas supply amount from the gas container 111a to the consumption facility 100, and a weight of the gas container 111a. And a weight detector 113a that substantially measures the remaining amount of the liquefied gas remaining in the gas container 111a by measuring Wa. Similarly, the liquefied gas supply source 11b includes a gas container 111b filled with liquefied gas, a pressure reducing valve 112b for controlling the amount of gas supplied from the gas container 111b to the consumption facility 100, and a weight Wb of the gas container 111b. And a weight detector 113b that substantially measures the remaining amount of liquefied gas remaining in the gas container 111b. Further, the control unit 21A adjusts the open / close degree of each of the pressure reducing valve 112a and the pressure reducing valve 112b based on the weights Wa and Wb measured by the weight detector 113a and the weight detector 113b.

  Here, it does not matter how much liquefied gas is filled in the gas container 111a and the gas container 111b initially. Rather, it is preferable to have a difference in the remaining amount in order to avoid simultaneous replacement. In the present invention, attention is paid to the difference in consumption, and the consumption rate is controlled to be substantially (globally) identical.

  In addition, as a concept of one supply source as shown to the liquefied gas supply source 11a and the liquefied gas supply source 11b, it is not limited to the concept of a gas container, a cylinder cabinet, a tank etc. All those controlled by one pressure reducing valve are conceivable, such as single substances or combinations of plural ones thereof. In that sense, the configurations of the liquefied gas supply source 11a and the liquefied gas supply source 11b are an example, and can be regarded as a schematic diagram. Further, the installation places of the liquefied gas supply source 11a and the liquefied gas supply source 11b are optional in the present invention, and may be physically close or distant, but they may be separated from each other. There are also cases where they are installed separately in consideration of loss due to factors etc.

Next, the control procedure of the control unit 21A will be described with reference to the flowchart of FIG. 1 (b).
The control unit 21A initially reduces the pressure at which the gas supply pressure is both set to the first set supply pressure SP1 (monitored by the pressure instruction controller (not shown) attached to each of the pressure reducing valve 112a and the pressure reducing valve 112b). The opening degree of 112a and the pressure-reduction valve 112b is adjusted (step S11).

  From this point on, the “monitoring period” starts, and the control unit 21A monitors the reduction amounts ΔWa and ΔWb of the gas weight corresponding to the gas consumption from the liquefied gas supply source 11a and the liquefied gas supply source 11b from this point. start. Then, the control unit 21A constantly checks whether “| ΔWa−ΔWb |”, which is the difference between the decrease amounts (consumption amounts), has reached the first threshold, which is the control start set value (step S12). ).

  Therefore, monitoring is continued if the first threshold (the first predetermined value) is not reached (negative determination in step S12), and if it is determined that the first threshold is reached (positive determination in step S12) The monitoring period is ended, and the degree of opening adjustment corresponding to the second set supply pressure SP2 smaller than the first set supply pressure SP1 is performed on the pressure reducing valve with the faster gas decrease (step S13).

  The "control period" starts from this point. In addition, when the supply pressure of one liquefied gas supply source is reduced in this way, while the gas consumption amount from the reduced liquefied gas supply source decreases, the liquefied gas supply source of the one whose supply pressure is not changed is Since the gas is preferentially supplied by the pressure difference, the gas supply amount increases.

  The control unit 21A continues to monitor the reduction amounts ΔWa and ΔWb of the gas weight corresponding to the gas consumption from the liquefied gas supply source 11a and the liquefied gas supply source 11b from the start of the monitoring period also during the control period. During the control period, has the second threshold (the second predetermined value), which is the control cancellation set value, smaller than the first threshold, “| ΔWa−ΔWb |”, which is the difference between the decrease amounts (consumption amounts)? It is checked whether or not it is (step S14).

  Therefore, control is continued when the second threshold is not reached (negative determination in step S14), and when it is determined that the second threshold is reached (positive determination in step S14), the control period is ended. Returning to step S11, with respect to the pressure reducing valve whose opening degree is adjusted corresponding to the second set supply pressure SP2, opening degree recovery corresponding to the first set supply pressure SP1 is performed.

  From this point on, the monitoring period restarts, and the control unit 21A starts monitoring the gas weights ΔWa and ΔWb corresponding to the gas consumption from the liquefied gas supply source 11a and the liquefied gas supply source 11b again.

  By the above control, the gas consumption rate of the liquefied gas supply source 11a and the gas consumption rate of the liquefied gas supply source 11b can be made substantially (generally) the same. Therefore, the gas piping replacement cycle in each gas supply source Can be identical, and replacement maintenance personnel can perform replacement maintenance systematically. In addition, at the same time the risk of gas supply outages due to out of gas is also eliminated, which is more effective as the gas loadings are initially different.

  Next, FIG. 2 is a diagram for explaining an embodiment in the case where the gas to be supplied is a compressed gas, (a) is a configuration diagram of the gas supply device, and (b) is a control thereof It is a flowchart which shows the operation processing of a part.

  In FIG. 2A, the gas supply device 1B includes a compressed gas supply source 12a and a gas container 121b, which are connected by piping in parallel with the consumption facility 100, and a control unit 21B. Here, the compressed gas supply source 12a includes a gas container 121a filled with compressed gas, a pressure reducing valve 122a for controlling the amount of gas supplied from the gas container 121a to the consumption facility 100, and the remainder of the gas container 121a. And a pressure detector 123a that measures the gas pressure Pa. Similarly, the compressed gas supply source 12b includes a gas container 121b filled with compressed gas, a pressure reducing valve 122b for controlling the amount of gas supplied from the gas container 121b to the consumption facility 100, and the remaining gas of the gas container 121b. And a pressure detector 123b that measures the pressure Pb. Further, the control unit 21B adjusts the open / close degree of each of the pressure reducing valve 122a and the pressure reducing valve 122b based on the residual gas pressure Pa and Pb respectively measured by the pressure detector 123a and the pressure sensor 123b.

  Here, it does not matter what amount of compressed gas is charged into the gas container 121a and the gas container 121b initially. Rather, it is preferable to have a difference in the remaining amount in order to avoid simultaneous replacement. In the present invention, attention is paid to the difference in consumption, and the consumption rate is controlled to be substantially (globally) identical.

Next, the control procedure of the control unit 21B will be described with reference to the flowchart of FIG. 2 (b).
The control unit 21B initially reduces both the supply pressure of the gas to the first set supply pressure SP1 (monitored by the pressure instruction controller (not shown) attached to each of the pressure reducing valve 122a and the pressure reducing valve 122b). The opening degree of the pressure reducing valve 122b is adjusted (step S21).

  From this time point, the “monitoring period” starts, and the control unit 21B monitors the reduction amounts ΔPa and ΔPb of the residual gas pressure corresponding to the gas consumption from the compressed gas supply source 12a and the compressed gas supply source 12b from this time. Get started. Then, the control unit 21B constantly determines whether “| ΔPa−ΔPb |”, which is the difference between the decrease amounts (consumption amounts), has reached the first threshold (the first predetermined value), which is the control start set value. It is checked (step S22).

  Therefore, monitoring is continued when the first threshold (first predetermined value) is not reached (negative determination in step S22), and when it is determined that the first threshold is reached (positive determination in step S22) The monitoring period is ended, and the degree of opening adjustment corresponding to the second set supply pressure SP2 smaller than the first set supply pressure SP1 is performed on the pressure reducing valve with the faster gas decrease (step S23).

  The "control period" starts from this point. In addition, when the supply pressure of one compressed gas supply source is reduced as described above, the gas consumption amount from the reduced compressed gas supply source is reduced, while the compressed gas supply source of the one which does not change the supply pressure is Since the gas is preferentially supplied by the pressure difference, the gas supply amount increases.

  The control unit 21B continues to monitor the reduction amounts ΔPa and ΔPb of the residual gas pressure corresponding to the gas consumption from the compressed gas supply source 12a and the compressed gas supply source 12b from the start of the monitoring period also during the control period, In this control period, “| ΔPa−ΔPb |”, which is the difference between the decrease amounts (consumption amounts), has reached the second threshold (second predetermined value), which is the control cancellation setting value, smaller than the first threshold. It is checked whether or not it is (step S24).

  Therefore, control is continued when the second threshold is not reached (negative determination in step S24), and when it is determined that the second threshold is reached (positive determination in step S24), the control period is ended. Returning to step S21, with respect to the pressure reducing valve whose opening degree has been adjusted corresponding to the second set supply pressure SP2, opening degree recovery corresponding to the first set supply pressure SP1 is performed.

  From this point on, the monitoring period restarts, and the control unit 21B starts monitoring the reduction amounts ΔPa and ΔPb of the residual gas pressure corresponding to the gas consumption from the compressed gas supply source 12a and the compressed gas supply source 12b again.

  By the above control, even in the case of the compressed gas shown in FIG. 2, the same effect as the effect in the case of the liquefied gas described in FIG. 1 can be obtained.

  Next, further specific embodiments will be described. FIG. 3 is a block diagram of the gas supply apparatus according to the embodiment, FIG. 4 is a graph showing the temporal transition of the residual gas pressure P etc., and FIG. 5 is a specific example along the temporal flow It is a table showing various numerical values and the like.

  As shown in FIG. 3, in the gas supply apparatus according to the present embodiment, two compressed gas supply sources 12a and 12b are connected in parallel to two consumption facilities 100a and 100b. There is. The configuration of each of the compressed gas supply source 12a and the compressed gas supply source 12b is the same as that shown in FIG. 2A, and the control unit 21B is omitted.

  In the present embodiment, the first set supply pressure SP1 and the second set supply pressure SP2 are 0.4 and 0.38, respectively, and the first threshold (control start set value) and the second threshold (control release set value) Are respectively 0.5 and 0.2. Further, referring to FIGS. 4 and 5, initially, residual gas pressures Pa and Pb measured by pressure detector 123a of compressed gas supply source 12a and pressure detector 123b of compressed gas supply source 12b are They are 5.0 and 8.0 respectively. It is preferable that these values be separated to some extent as described above.

  First, the control unit 21B sets both the pressure reducing valve 122a of the compressed gas supply source 12a and the pressure reducing valve 122b of the compressed gas supply source 12b to an opening degree corresponding to 0.4 determined as the first set supply pressure SP1. To start the gas supply. Thus, the monitoring period m1 starts. In the present embodiment, it is assumed that the gas consumption rate of the compressed gas supply source 12a is relatively higher than the gas consumption rate of the compressed gas supply source 12b even at the same set supply pressure.

  The monitoring period m1 continues, and the residual gas pressure Pa measured by the pressure detector 123a for the compressed gas supply source 12a falls from 5.0 to 4.0, and is measured by the pressure detector 123b for the compressed gas supply source 12b. When the residual gas pressure Pb decreases from 8.0 to 7.5, “| ΔPa−ΔPb |” corresponding to the difference in consumption is (5.0−4.0) − (8.0−7.5). Since the first threshold is reached, the control unit 21B determines the opening degree of the pressure reducing valve 122a of the compressed gas supply source 12a as the second set supply pressure SP2 0.38. Change to the opening corresponding to. At this point, the monitoring period m1 ends and the control period c1 starts.

  When the control period c1 continues and the residual gas pressure Pa falls from 4.0 to 3.9 and the residual gas pressure Pb falls from 7.5 to 7.1, the amount of consumption is equivalent to “| ΔPa−ΔPb”. Since the || becomes (5.0−3.9) − (8.0−7.1) = 0.2 = the second threshold and the second threshold is reached, the control unit 21B is configured to supply the compressed gas supply source. The opening degree of the pressure reducing valve 122a of 12a is returned to the opening degree corresponding to 0.4 determined as the first set supply pressure SP1. At this point, the control period c1 ends and the monitoring period m2 starts (the monitoring period resumes).

  The monitoring period m2 continues, and when the residual gas pressure Pa falls from 3.9 to 2.9 and the residual gas pressure Pb falls from 7.1 to 6.6, the amount of consumption is equivalent to “| ΔPa−ΔPb”. Becomes | (3.9-2.9)-(7.1-6.6) = 0.5 = 1st threshold, and returns to 1st threshold, control part 21B is compressed gas supply source 12a. The opening degree of the pressure reducing valve 122a is changed again to the opening degree corresponding to 0.38 determined as the second set supply pressure SP2. At this point, the monitoring period m2 ends and the control period c2 starts.

When the control period c2 continues and the residual gas pressure Pa falls from 2.9 to 2.8 and the residual gas pressure Pb falls from 6.6 to 6.2, the amount of consumption is equivalent to “| ΔPa−ΔPb”. Since || becomes (3.9-2.8)-(7.1-6.2) = 0.2 = 2nd threshold value and reaches 2nd threshold value again, control part 21 B supplies compressed gas. The opening degree of the pressure reducing valve 122a of the source 12a is returned to the opening degree corresponding to 0.4 determined as the first set supply pressure SP1. At this point, the control period c2 ends and the next monitoring period starts.
Hereinafter, similarly, the monitoring period and the control period are repeated.

  As mentioned above, also in this embodiment. As can be seen from the change in residual gas pressure of each of the compressed gas supply source 12a and the compressed gas supply source 12b shown in FIG. 4, the difference in consumption, in other words, the consumption rate is substantially the same (generally). I have control. From the microscopic point of view of each period, the difference in consumption is within a certain range.

  In addition, in the above embodiment, although the gas supply apparatus in case the number of gas supply sources was two was demonstrated, it can apply similarly, also when the number of gas supply sources is three or more. That is, based on the gas supply source with the lowest gas consumption rate, the consumption rates of the other gas supply sources are controlled to follow the consumption rate of the gas supply source with the lowest gas consumption rate. As a result, the period of each monitoring period and control period of the other gas supply source will be different depending on the consumption rate.

  As described above, according to the above-described embodiment, the gas consumption rates of the plurality of gas supply sources 11a and 11b (12a and 12b) can be substantially (generally) according to any of the liquefied gas and the compressed gas. By making them identical, the replacement cycle of each gas source can be made the same, which facilitates maintenance plans for maintenance personnel and their work, and it is necessary to replace each gas source at the same time. Since it is not, it is possible to avoid the situation where the gas supply is stopped for the consumption facility.

  The gas supply apparatus and the gas supply method of the present invention may be employed, for example, in the case of installing a plurality of gas supply sources at physically different sites and supplying gas to consumption facilities in parallel. it can.

  1A, 1B: gas supply apparatus 11a, 11b: liquefied gas supply source 12a, 12b: compressed gas supply source 111a, 111b, 121a, 121b: gas container 112a, 112b, 122a, 122b ... pressure reducing valve, 113a, 113b ... weight detector, 123a, 123b ... pressure detector, 21A, 21B ... control unit, 100 ... consumption equipment, 101 ... gas supply source, 1011 ... gas container, 1012 ... pressure reducing valve

Claims (4)

Two or more gas supply sources connected in parallel to the equipment to be supplied with gas via piping, and capable of supplying gas simultaneously;
A control unit configured to control a gas supply pressure to the equipment of each of two or more of the gas supply sources;
The control unit controls each gas supply pressure so that the gas consumption rate of each of the two or more gas supply sources is substantially the same.   The gas supply device according to claim 1, wherein the control unit controls each gas supply pressure such that a difference in gas consumption of each of the two or more gas supply sources falls within a predetermined range. The control unit
Initially, a first set supply pressure is set as the gas supply pressure for all two or more of the gas supply sources,
The gas supply pressure relative to the gas supply source at which the difference in gas consumption has reached a first predetermined value as compared to the gas supply source having the smallest gas consumption rate of the two or more gas supply sources. Setting a second set supply pressure lower than the first set supply pressure,
3. The gas supply device according to claim 2, wherein the gas supply pressure is returned to the first set supply pressure when the difference in gas consumption reaches a second predetermined value. The gas supply pressure to the equipment of two or more gas supply sources connected in parallel to the equipment to be supplied with gas and capable of simultaneously supplying gas, and each of the two or more gas supply sources is controlled A control unit, and a gas supply method in a gas supply apparatus comprising:
The control method controls each gas supply pressure such that the gas consumption rate of each of the two or more gas supply sources is substantially the same.

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