JP2019136639A - Water treatment system - Google Patents

Abstract

To provide a water treatment system in which cavitation is suppressed and loss of flow control and damage to system are prevented.SOLUTION: According to the present invention, provided is a water treatment system 10 for purification-processing water, comprising a first control valve FCV1 and a second control valve FCV2 capable of controlling the opening, a control means 15, and purification means 11,12 and in which the first control valve FCV1, the second control valve FCV2 and the purification means 11,12 are each disposed on a purification line through which water circulates during purification-processing, and the control means 15 performs opening control of at least one of the first control valve FCV1 and the second control valve FCV2 in order to maintain an opening difference, which is a difference between the openings of the first control valve FCV1 and the second control valve FCV2, at constant.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a water treatment apparatus that purifies water.

  A ship such as a tanker usually stores water called ballast water in a ballast tank in order to balance the ship in operation when navigating to the destination again after unloading the crude oil. Such a ship is provided with a water treatment device (ballast water treatment device) for purifying ballast water in order to prevent the destruction of the ecosystem due to the pouring and discharging of ballast water (see Patent Document 1).

JP 2014-227063 A

  By the way, in the ballast water treatment device, depending on dirt or the like of the ballast water, the flow rate of the ballast water to be treated is reduced by restricting the opening of the valve (opening adjustment valve) provided in the pipeline for reliable purification treatment. There is. However, in such a case, cavitation may occur due to a rapid drop in pressure before and after the opening adjustment valve, which may make it impossible to adjust the flow rate, and may damage the valve and other equipment.

  In addition, the problem which arises by restrict | squeezing a valve in this way arises not only in the ballast water treatment apparatus which processes seawater, but in the whole water treatment apparatus which processes water, such as a river, a lake, a pond, and industrial water.

  This invention is made | formed in view of such a situation, and it aims at providing the water treatment apparatus which suppresses cavitation and can prevent that a flow volume adjustment becomes impossible or a facility is damaged. And

  According to the present invention, there is provided a water treatment apparatus for purifying water, comprising a first adjustment valve and a second adjustment valve capable of adjusting an opening, a control means, and a purification means, wherein the first adjustment valve, The second adjustment valve and the purification means are each disposed on a purification line through which water flows during purification treatment, and the control means performs opening control of at least one of the first adjustment valve and the second adjustment valve. A water treatment device is provided that maintains a difference in opening, which is a difference between the opening of the first adjustment valve and the opening of the second adjustment valve, substantially constant.

  According to such a configuration, the control means performs control so that the opening degree of the first adjustment valve and the opening degree of the second adjustment valve are maintained at a constant opening degree difference, so that water flows during the purification process. It is possible to reduce the pressure in the purification line step by step in each regulating valve, and prevent a sudden pressure drop. As a result, the simple control of making the opening difference between the two valves constant makes it possible to suppress cavitation even when the flow rate is reduced, making it impossible to adjust the flow rate, It is possible to prevent damage.

  Hereinafter, various embodiments of the present invention will be exemplified. The following embodiments can be combined with each other.

  Preferably, the control means controls the opening degree of at least one of the first adjustment valve and the second adjustment valve based on the processing capability of the purification means.

  Preferably, the control means adjusts the flow rate of water flowing through the control of either the first adjustment valve or the second adjustment valve, and the other of the first adjustment valve and the second adjustment valve. The opening degree difference is maintained substantially constant by controlling the above.

  Preferably, the first regulating valve is disposed upstream of the second regulating valve, and the control means regulates a flow rate of water flowing under the control of the second regulating valve, and the first regulating valve The opening degree difference is maintained substantially constant by control.

Preferably, the value of the opening degree difference that is maintained substantially constant is determined according to at least one of the following indexes A to D.
A: Maximum flow rate of water flowing through the purification line B: Minimum flow rate of water flowing through the purification line C: Pressure downstream of the first regulating valve D: of the first regulating valve and the second regulating valve Caliber

It is a figure which shows the outline of the ballast apparatus which introduced the water treatment apparatus 10 which concerns on embodiment of this invention. It is a figure which shows the flow path at the time of bypassing the filtration apparatus 11 and the ultraviolet reactor 12 in the water treatment apparatus 10 of FIG. In the water treatment apparatus 10 of FIG. 1, it is a figure which shows the flow path at the time of circulating the filtration apparatus 11 and the ultraviolet reactor 12, and purifying ballast water. It is a figure which shows the flow path at the time of bypassing only the filtration apparatus 11 in the water treatment apparatus 10 of FIG.

  Hereinafter, embodiments of the present invention will be described. Various characteristic items shown in the following embodiments can be combined with each other. The invention is established independently for each feature.

1. Configuration of Ballast Device FIG. 1 is a schematic diagram showing a state in which a water treatment device (ballast water treatment device) 10 according to an embodiment of the present invention is introduced into a ballast device of a ship. The ballast device includes a ballast operation for taking inboard water such as seawater from the sea chest SC1 into the ship and injecting water into the ballast tank 2, and a deballast for discharging the ballast water stored in the ballast tank 2 from the outboard outlet SC2. Operation. As shown in FIG. 1, the ballast device of the present embodiment mainly includes a pump 1 that pumps ballast water that circulates in the ship, a water treatment device 10, and a ballast tank 2. Hereinafter, the configuration of the water treatment apparatus 10 will be mainly described.

  As for “ballast water” in this specification, all the water taken into the ship is “ballast water” regardless of whether it is introduced (inflowed) into the ballast tank 2 or discharged (outflowed) from the ballast tank 2. It expresses. The ballast water taken into the ship includes seawater, fresh water, brackish water, and the like.

2. Configuration of the water treatment apparatus 10 The water treatment apparatus 10 is introduced to reduce the content of microorganisms / foreign substances contained in the ballast water by treating the ballast water taken into the ship and discharged from the ship. . As shown in FIG. 1, the water treatment apparatus 10 is provided between the pump 1 and the ballast tank 2 (or the outboard discharge port SC2). Here, in the water treatment apparatus 10, the connection part on the pump 1 side is the upstream connection part P1, and the connection part on the ballast tank 2 side is the downstream connection part P2.

  The water treatment device 10 of the present embodiment includes a filtration device 11 that filters ballast water using a filter, an ultraviolet reactor 12 that sterilizes microorganisms by irradiating the ballast water with ultraviolet rays, and a flow meter that measures the flow rate of the ballast water. 13, a pressure gauge 14 that measures the water pressure of the ballast water, and a control unit 15 that controls the circulation of the ballast water that circulates in the water treatment apparatus 10. The filtration device 11 and the ultraviolet reactor 12 are also referred to as purification means. In this embodiment, known configurations are used for the filtering device 11 and the ultraviolet reactor 12. In this embodiment, the water treatment device 10 is provided between the pump 1 and the ballast tank 2 (or the outboard discharge port SC2).

  Moreover, the water treatment apparatus 10 is provided with several lines L1-L5 which connect each component and distribute | circulate ballast water. “Line” is a general term for lines capable of flowing fluid such as flow paths, paths, and pipelines. The water treatment apparatus 10 also includes on-off valves V1 to V5, and a first adjustment valve FCV1 and a second adjustment valve FCV2 that can adjust the opening degree. In addition, about the line L1 of the water treatment apparatus 10, you may use the existing line in a ship as some pipe lines. Therefore, in the water treatment apparatus 10, the line L1 is not an essential configuration. Moreover, it is also possible to use the existing line in a ship partially about the line L2-line L5.

  Specifically, as shown in FIG. 1, the line L1 is a line that bypasses the filtration device 11 and the ultraviolet reactor 12 and connects the upstream side connection portion P1 and the downstream side connection portion P2, and includes an on-off valve V1. The line L2 is a line connecting the line L1 and the filtration device 11, and includes an on-off valve V2. The line L3 is a line that connects the filtering device 11 and the ultraviolet reactor 12, and includes an on-off valve V3. The line L4 has one end connected to a position downstream of the connection position of the line L1 with the line L2 and upstream of the on-off valve V1, and the other end connected to the on-off valve V3 of the line L3. Connected to a downstream position. The line L4 has an on-off valve V4. One end of the line L5 is connected to the ultraviolet reactor 12, and the other end is connected to a position downstream of the on-off valve V1 of the line L1. In the present embodiment, the flow meter 13 is installed on the line L5, and the pressure gauge 14 is installed on the upstream side of the connection position of the line L1 with the line L4.

  In addition, the water treatment device 10 of the present embodiment is provided with a first adjustment valve FCV1 whose opening degree can be adjusted at a position upstream of the connection position of the line L1 with the line L2, and from the flow meter 13 of the line L5. Also, a second adjustment valve FCV2 capable of adjusting the opening degree is provided at a downstream position.

  The control means 15 controls the flow of ballast water flowing through the water treatment apparatus 10 by controlling the opening / closing of the on-off valves V1 to V5. The control means 15 also performs control for adjusting the opening degree of the first adjustment valve FCV1 and the second adjustment valve FCV2 based on the processing capability of the purification means in order to adjust the flow rate of the ballast water flowing through the purification means. Here, the processing capacity of the purification means is a flow rate that can be processed for each water quality (turbidity) of the ballast water, and includes, for example, an irradiation amount of ultraviolet rays by the ultraviolet reactor 12. Another example is the differential pressure between the primary side and the secondary side of the filter of the filtration device 11.

3. Operation of Water Treatment Device 10 Next, the operation of the water treatment device 10 configured as described above will be described. The following operation is performed under the control of the control means 15.

3.1 Bypass operation Immediately after the pump 1 is driven or when purification of the ballast water is not necessary, the control means 15 opens the on-off valve V1 and the first regulating valve FCV1, and closes the other on-off valves so that the ballast water flows into the line L1. The filter device 11 and the ultraviolet reactor 12 are bypassed (see FIG. 2).

3.2 Purification Operation When the ballast water is purified by the water treatment device 10, the control means 15 closes the on-off valves V1 and V4, and opens the on-off valves V2 and V3, the first regulating valve FCV1 and the second regulating valve FCV2, and ballasts. Water is allowed to flow through the filtering device 11 and the ultraviolet reactor 12 (purifying means) (see FIG. 3). At this time, the control means 15 also outputs start-up commands for the filtration device 11 and the ultraviolet reactor 12. Ballast water is purified by passing through the filtration device 11 and the ultraviolet reactor 12. Here, in the present embodiment, the lines that circulate through the first regulating valve FCV1, the filtering device 11, the ultraviolet reactor 12, and the second regulating valve FCV2 shown in FIG. 3, that is, a part of the line L1 and the lines L2 to L4. Is also called “Purification Line”. When the on-off valve V5 of the ballast device is closed and the on-off valve V6 is opened, the purified ballast water is stored in the ballast tank 2, and when the on-off valve V5 is opened and the on-off valve V6 is closed, the purified ballast Water is discharged out of the ship.

  Here, the control means 15 also controls the flow rate of the ballast water that performs the purification process, that is, the flow rate of the ballast water that flows through the filtration device 11 and the ultraviolet reactor 12. The flow rate of the circulated ballast water is measured by the flow meter 13. Below, the flow control of the ballast water which performs a purification process is demonstrated concretely.

  The control means 15 basically adjusts the flow rate of the ballast water that circulates by controlling the opening degree of the second regulating valve FCV2. That is, when there is a large amount of purifying treatment by the filtration device 11 and the ultraviolet reactor 12, such as when the quality of the ballast water being distributed is good, the flow rate of the ballast water is increased by increasing the opening of the second regulating valve FCV2. On the other hand, when the quality of the circulated ballast water is poor, for example, when the amount that can be purified by the filtration device 11 and the ultraviolet reactor 12 is small, the flow rate of the ballast water is reduced by lowering the opening of the second regulating valve FCV2. In addition, it is preferable to set the flow volume of the ballast water to distribute | circulate to the smaller rated flow volume among the rated flow volume which the filtration apparatus 11 can filter-process, and the rated flow volume which the ultraviolet reactor 12 can kill microorganisms. Thereby, the ballast water appropriately treated by the purifying means can be stored or discharged in the shortest time.

  By the way, in the water treatment apparatus 10, when it is necessary to reduce the flow rate of the ballast water to be purified, if the opening degree of the second regulating valve FCV2 is lowered, the pressure rapidly decreases before and after the second regulating valve FCV2. May cause cavitation, making it impossible to adjust the flow rate or damaging valves and other equipment.

  Therefore, in the water treatment apparatus 10 of the present embodiment, the first regulating valve FCV1 is separately installed, and the flow rate of water flowing through the purification means is reduced (for example, the opening degree of the second regulating valve FCV2 is 30% or less). When the control means 15 controls the opening degree of the second regulating valve FCV2, the opening degree of the first regulating valve FCV1 is simultaneously controlled. Specifically, the control means 15 opens the first adjustment valve FCV1 so that the opening difference, which is the difference in opening between the first adjustment valve FCV1 and the second adjustment valve FCV2, is maintained substantially constant in the low flow rate region. Keeping the degree. That is, the control means 15 keeps the opening degree difference between the first adjustment valve FCV1 and the second adjustment valve FCV2 substantially constant while performing flow rate control. Here, the opening degree difference is more specifically defined as + X% (X is an integer of 0 or more). By doing in this way, a pressure falls in steps at the position of two regulating valves, the 1st regulating valve FCV1 and the 2nd regulating valve FCV2. As a result, a rapid pressure drop at the position of the second regulating valve FCV2 is suppressed, and the occurrence of cavitation can be suppressed. Here, if the opening degree of the first regulating valve FCV1 is reduced, the flow rate of the ballast water flowing through the water treatment device 10 is decreased. In this case, the second flow rate is measured based on the flow rate measured by the flow meter 13. The flow rate of the ballast water can be controlled to an appropriate flow rate by adjusting the opening of the adjustment valve FCV2.

  In addition, when the aperture of the first regulating valve FCV1 and the aperture of the second regulating valve FCV2 are the same, the opening of the first regulating valve FCV1 is preferably larger than the opening of the second regulating valve FCV2. This is because the first regulating valve FCV1 is installed for the purpose of gently adjusting the pressure in the purification line. However, when the aperture of the first adjustment valve FCV1 and the aperture of the second adjustment valve FCV2 are different, or depending on other situations, the opening may be set to a value smaller than the opening of the second adjustment valve FCV2. Moreover, maintaining substantially constant means maintaining the width | variety of the allowable value of an opening degree difference within predetermined. This width can be, for example, within ± 3%, preferably within ± 2%, and more preferably within ± 1%. Note that the substantially constant value also allows a slight time lag that occurs when the first adjustment valve FCV1 follows the opening degree corresponding to the opening degree of the second adjustment valve FCV2.

  By such control, when the opening degree of the second adjustment valve FCV2 is large, that is, when the flow rate of ballast water is large, the opening degree of the first adjustment valve FCV1 is also increased. Is not limited.

  Note that the control for maintaining the opening degree difference substantially constant may be performed only in the low flow rate range, and in other cases than the low flow rate range, for example, the flow rate of the second adjustment valve FCV2 is greater than 30%. The same control may be performed in the area. However, when performing control to maintain the opening degree difference substantially constant in the entire flow rate range, the opening degree difference cannot be maintained substantially constant when one opening degree reaches 100% (or 0%). Therefore, in this case, the opening difference need not be constant.

  As described above, the water treatment apparatus 10 according to the present embodiment is configured by simple control (opening control) that makes the opening difference between the two regulating valves, the first regulating valve FCV1 and the second regulating valve FCV2, constant. Even in a state where the flow rate is reduced, cavitation can be suppressed, and it is possible to prevent the flow rate from being adjusted and the equipment from being damaged. Therefore, it is not essential to provide other detection means such as a pressure sensor, and it is possible to configure the water treatment apparatus 10 that is inexpensive, simple, and highly reliable.

Note that the value of the opening degree difference that is maintained substantially constant is determined according to at least one of the following indexes A to D.
A: Maximum flow rate of ballast water flowing through the purification line B: Minimum flow rate of ballast water flowing through the purification line C: Pressure measured by the pressure gauge 14: Diameters of the first adjustment valve and the second adjustment valve

  Specifically, A: the maximum flow rate of ballast water flowing through the purification line is the maximum flow rate to be processed by the purification means (for example, the smaller of the rated flow rates of the filtering device 11 and the ultraviolet reactor 12). When the opening degree difference is determined based on the maximum flow rate, the opening degree difference is increased when the maximum flow rate is large, and the opening degree difference is decreased when the maximum flow rate is small. B: The minimum flow rate of the ballast water flowing through the purification line is the minimum flow rate to be processed by the purification means. This flow rate is, for example, the minimum flow rate that can ensure the irradiation amount of ultraviolet rays by the ultraviolet reactor 12 even when the turbidity of ballast water is high. When the opening degree difference is determined based on the minimum flow rate, the opening degree difference is increased when the minimum flow rate is large, and the opening degree difference is decreased when the minimum flow rate is small.

  The C: pressure measured by the pressure gauge 14 is a pressure on the downstream side of the first regulating valve FCV1. When determining the opening difference based on the pressure, if the pressure is high with the minimum flow rate flowing, the opening of the first adjustment valve is decreased, and the opening of the second adjustment valve is increased to fit the target pressure. Determine the difference. When the pressure is low, the opening degree of the first adjusting valve is increased, and the opening degree of the second adjusting valve is decreased to determine the opening difference that falls within the target pressure. D: When the opening degree difference is determined by the diameter, when the diameter of the first adjustment valve is larger, the opening degree of the first adjustment valve is reduced, and when the diameter of the second adjustment valve is smaller, Increase the opening of the second adjustment valve.

By appropriately setting the opening degree difference by such an index, it is possible to more effectively suppress the occurrence of cavitation.

  In the above description, an example in which ballast water is circulated through both the filtration device 11 and the ultraviolet reactor 12 for purification is described. However, for example, during the deballast operation, the on-off valves V2 and V3 are closed and the on-off valve V4 is closed. It is also possible to bypass the filtration device 11 by opening and perform only the processing of the ultraviolet reactor 12 (see FIG. 4). In the ballast device, during the deballast operation, the ballast water stored in the ballast tank 2 flows into the water treatment device 10 via the line L6 and the pump 1 by opening the on-off valve V7. Also at this time, by controlling the first regulating valve FCV1 and the second regulating valve FCV2 by the control means 15, it is possible to suppress the occurrence of cavitation even when the flow rate is reduced.

4). Modifications The present invention can also be implemented in the following modes.
In the above embodiment, the controller 15 controls both the first regulator valve FCV1 and the second regulator valve FCV2, but the second regulator valve FCV2 is not controlled by the controller, for example, manually operated It is also possible to do. In this case, the control means 15 acquires the opening degree of the second regulating valve FCV2 and controls the opening degree of the first regulating valve FCV1.
In the above embodiment, the first regulating valve FCV1 is disposed upstream of the filtering device 11, and the second regulating valve FCV2 is disposed downstream of the ultraviolet reactor 12. However, the first regulating valve FCV1 and the first regulating valve FCV1 The 2 regulating valve FCV2 can be installed at an arbitrary position on the purification line (lines L2, L3, L5). For example, both the first regulating valve FCV1 and the second regulating valve FCV2 are arranged upstream of the filtering device 11, and both the first regulating valve FCV1 and the second regulating valve FCV2 are arranged downstream of the ultraviolet reactor 12. It is also possible to do. Further, one or both of the first regulating valve FCV1 and the second regulating valve FCV2 can be arranged at a position between the filtering device 11 and the ultraviolet reactor 12. It is also possible to arrange the second adjustment valve FCV2 for mainly adjusting the opening degree on the upstream side of the first adjustment valve FCV1.
In the above embodiment, the water treatment device 10 includes the two purification means of the filtration device 11 and the ultraviolet reactor 12, but the configuration including only the purification device of the filtration device 11 and the ultraviolet reactor 12, It is also possible to adopt a configuration using purification means.
-Although the example which applied the water treatment apparatus 10 to the ballast apparatus was shown in the said embodiment, the water treatment apparatus 10 of this invention is not only a ballast apparatus but various waters, such as a river, a lake, a pond, and industrial water. It can be used as a water treatment device for treating water.

1: Pump 2: Ballast tank 10: Water treatment device 11: Filtration device (purification means)
12: UV reactor (purification means)
13: Flow meter 14: Pressure gauge 15: Control means FCV1: First adjustment valve FCV2: Second adjustment valves L1 to L6: Line P1: Upstream side connection P2: Downstream side connection SC1: Sea chest SC2: Outboard discharge Outlets V1 to V7: Open / close valve

Claims (5)

A water treatment device for purifying water,
A first adjustment valve and a second adjustment valve capable of adjusting the opening, a control means, and a purification means;
The first regulating valve, the second regulating valve, and the purification means are each disposed on a purification line through which water flows during purification processing,
The control means performs opening control of at least one of the first adjustment valve and the second adjustment valve, and calculates an opening difference that is a difference between the opening of the first adjustment valve and the opening of the second adjustment valve. A water treatment device that maintains a constant level. The water treatment device according to claim 1,
The said control means is a water treatment apparatus which performs the opening degree control of at least one of the said 1st regulating valve and the said 2nd regulating valve based on the processing capacity of the said purification | cleaning means. The water treatment device according to claim 1,
The control means adjusts a flow rate of water flowing through control of either the first control valve or the second control valve, and controls either of the first control valve or the second control valve. A water treatment apparatus that maintains the opening degree difference substantially constant. The water treatment device according to claim 1,
The first regulating valve is disposed upstream of the second regulating valve;
The said control means is a water treatment apparatus which adjusts the flow volume of the water distribute | circulated by control of the said 2nd regulating valve, and maintains the said opening degree difference substantially constant by control of the said 1st regulating valve. The water treatment device according to any one of claims 1 to 3,
The value of the difference in opening degree maintained substantially constant is determined according to at least one index of A to D below.
A: Maximum flow rate of water flowing through the purification line B: Minimum flow rate of water flowing through the purification line C: Pressure downstream of the first regulating valve D: of the first regulating valve and the second regulating valve Caliber