Ozone supply device and method for operating ozone supply device

Abstract

Provided is an ozone supply device comprising: a plurality of ozone generators (3a, 3b, 3c) that generate ozone from supplied oxygen; adsorption devices (41a, 41b) that are provided in a smaller number than the total number of the ozone generators (3a, 3b, 3c) and that separate, from a mixed gas that is supplied from the ozone generators (3a, 3b, 3c) and that is composed of oxygen and ozone, oxygen contained in the mixed gas by adsorbing ozone; oxygen transfer devices (42) that are provided in a smaller number than the total number of the ozone generators (3a, 3b, 3c) and that transfer oxygen separated from the mixed gas by the adsorption devices (41a, 41b) to the ozone generators (3a, 3b, 3c); first shared piping (10a) for connecting, in a shared manner, the outlet side of the oxygen transfer devices (42) and the inlet side of the ozone generators; and second shared piping (10b) for connecting, in a shared manner, the inlet side of the adsorption devices (41a, 41b) and the outlet side of the ozone generators.

Description

Ozone supply device and method for operating the ozone supply device

[0001] The present disclosure relates to an ozone supply device and a method for operating an ozone supply device.

[0002] The amount of ozone injected for the purpose of ozone treatment at a water purification plant is calculated by multiplying the ozone injection rate by the amount of water to be treated. For example, when reducing precursors of trihalomethanes (THMs) at a water purification plant, these compounds are concentrated in the summer, requiring a high ozone injection rate. Furthermore, the amount of water to be treated is typically large in the summer. Therefore, the maximum ozone injection rate, which is the design value for determining the capacity and number of ozone generators, is set by multiplying the amount of water to be treated by the ozone injection rate based on the summer season, taking into account daily water volume fluctuations and a margin of error.

[0003] On the other hand, in actual operation outside of summer, a low ozone injection amount is sufficient, so it is common for a system of multiple ozone supply devices to be operated at a low load and with a low number of ozone generators relative to the total equipment capacity. Also, in ozone supply devices that use conventional oxygen recycling technology, the oxygen recycling equipment capacity and number of devices are equivalent to those of the ozone generators.

[0004] Furthermore, a conventional ozone supplying apparatus including related equipment is disclosed in Patent Document 1. That is, an ozone supplying apparatus including an ozone generator that generates ozone, an adsorption / desorption tower that adsorbs and desorbs the ozone, an ozonated gas transfer circuit that transfers the ozonated gas generated in the ozone generator to the adsorption / desorption tower, a pressurization mechanism that introduces a pressurized carrier gas into the adsorption / desorption tower or a depressurization mechanism that depressurizes the adsorption / desorption tower, an ozone buffer device that contains an adsorbent that adsorbs the ozone and suppresses fluctuations in the concentration of the introduced ozone, and a desorption gas transfer circuit that transfers the ozone desorbed from the adsorption / desorption tower to the ozone buffer device and then supplies the ozone to a supply target (see, for example, Patent Document 1).

[0005] Patent No. 7292554

[0006] However, with ozone supply equipment that applies conventional oxygen recycling technology, the oxygen recycling equipment capacity and number of units must be equivalent to that of ozone generators. This means that, particularly at power stations where there are large fluctuations in the concentration of the material being treated and in the amount of treated water, the actual operational load and operating rate are low compared to the equipment capacity of the entire system, and there are economic issues such as the energy-saving effect of oxygen recovery being low compared to the cost of installing the oxygen recycling equipment.

[0007] Furthermore, in the past, ozone generators and oxygen recycling equipment were often installed in a one-to-one correspondence, so even if the oxygen recycling equipment broke down, backup operation was possible using another ozone generator and oxygen recycling equipment if one was available. However, in such cases, the installation of multiple oxygen recycling equipment increased the installation space for the ozone supply device, and the maintenance costs increased due to the complexity of the equipment. On the other hand, when oxygen recycling equipment was shared by multiple ozone generators, there was a problem that backup operation became difficult if the oxygen recycling equipment broke down.

[0008] This disclosure discloses a technology for solving the above-mentioned problems, and aims to improve energy savings through oxygen recovery by configuring an apparatus that can share equipment for separating and transporting oxygen, thereby increasing the load or operating rate of the oxygen recycling equipment even when operating with a small amount of ozone injected. Furthermore, by sharing the oxygen recycling equipment, it is possible to simplify the ozone supply device, reduce equipment installation costs, maintenance costs, and installation space, thereby improving investment effectiveness.

[0009] The ozone supply device of the present disclosure is characterized by comprising: a plurality of ozone generators that generate ozone from oxygen; adsorption devices, the number of which is less than the total number of the ozone generators, that separate oxygen contained in a mixed gas composed of oxygen and the ozone and supplied from the ozone generators by adsorbing the ozone from the mixed gas; oxygen transfer devices, the number of which is less than the total number of the ozone generators, that transfer the oxygen separated from the mixed gas by the adsorption devices to the ozone generators; a first shared pipe that connects, in common, an outlet side of the oxygen transfer device from which oxygen is delivered and an inlet side of the ozone generator to which oxygen is supplied; and a second shared pipe that connects, in common, an inlet side of the adsorption device to which the mixed gas is supplied and an outlet side of the ozone generator to which the mixed gas is delivered.

[0010] According to the ozone supplying device of the present disclosure, by configuring the device so that the equipment for separating and transporting oxygen can be shared, the load on the oxygen recycling equipment or the operating rate can be increased even when operating with a small amount of ozone injected, thereby improving energy savings through oxygen recovery. Furthermore, by sharing the oxygen recycling equipment, the ozone supplying device can be simplified, and the equipment installation costs, maintenance costs, and installation space can be reduced, thereby improving investment effectiveness.

[0011] FIG. 1 is a system diagram showing an example of an ozone supplying apparatus according to embodiment 1. FIG. 2 is a system diagram showing in detail main parts of the ozone supplying apparatus according to embodiment 1. FIG. 3 is a diagram for systematically explaining an example of an ozone supplying apparatus according to embodiment 1 during ozone adsorption. FIG. 4 is a diagram for systematically explaining an example of an ozone supplying apparatus according to embodiment 1 during ozone desorption. FIG. 5 is a system diagram showing an example of an ozone supplying apparatus according to embodiment 2. FIG. 6 is a flowchart showing an operating method of the ozone supplying apparatus according to embodiment 2. FIG. 7 is a system diagram showing an example of an ozone supplying apparatus according to embodiment 3. FIG. 8 is a flowchart showing an operating method of the ozone supplying apparatus according to embodiment 3.

[0012] The present disclosure relates to an ozone supplying device and an operating method of the ozone supplying device, which are provided with an oxygen recycling facility that selectively adsorbs ozone from ozone-containing oxygen gas output from multiple ozone generators using an adsorbent, and reuses the oxygen that is not adsorbed and separated as a raw material for the ozone generator, in public water supply and sewerage systems and private wastewater treatment plants for the purpose of ozone treatment.

[0013] In particular, the present invention relates to an ozone supplying apparatus equipped with an oxygen recycling facility that reuses unadsorbed oxygen as a raw material for the ozone generator, and characterized in that the oxygen recycling facility is shared by the entire ozone supplying apparatus consisting of a plurality of ozone generators.

[0014] First Embodiment An example of an ozone supplying apparatus according to a first embodiment will be described below with reference to the block diagrams of FIGS.

[0015] 1 is a processing system diagram illustrating an example of an ozone supplying apparatus according to Embodiment 1. The ozone supplying apparatus of the present disclosure outputs compressed air supplied from multiple compressed air supplying apparatuses 1a, 1b, and 1c (hereinafter also referred to as compressed air supplying apparatuses 1a-1c) to a compressed air header pipe 11a (hereinafter also referred to as third shared piping 11a) shared by these multiple compressed air supplying apparatuses, thereby supplying the compressed air to multiple oxygen supplying apparatuses 2a, 2b, and 2c via this compressed air header pipe 11a. The oxygen supplied from these multiple oxygen supplying apparatuses 2a-2c is supplied to multiple ozone generators 3a, 3b, and 3c (hereinafter also referred to as ozone generators 3a-3c) via an oxygen header pipe 10a (hereinafter also referred to as first shared piping 10a) shared by these multiple oxygen supplying apparatuses 2a-2c. Next, these ozone generators 3a to 3c generate ozone from the supplied oxygen, and the ozone and excess oxygen are transferred as a mixed gas to an ozonized-oxygen header pipe 10b shared by the ozone generators 3a to 3c. This mixed gas contains at least the generated ozone and the excess oxygen. The ozone and oxygen are then sent to the oxygen recycling facility 4 via the ozonized-oxygen header pipe 10b. In the oxygen recycling facility 4, the ozone is adsorbed, and only the oxygen is returned to the oxygen header pipe 10a for recycling. Each of the ozone generators 3a to 3c has a power supply unit (a combination of an inverter and a step-up transformer; not shown) that supplies power to the electrodes housed therein. By changing the voltage and frequency with this power supply unit, the power supplied to the electrodes can be adjusted, thereby increasing or decreasing the concentration of generated ozone. In addition, the first shared piping 10a connects the outlet side of the oxygen transfer device, which is the side from which oxygen is sent out from the oxygen transfer device, and the inlet side of the ozone generator, which is the side from which oxygen is supplied to the ozone generator, and is shared among multiple ozone generators.

[0016] On the other hand, compressed air supplied from a plurality of compressed air supply facilities 1a to 1c is sent to the oxygen recycling facility 4 and used to desorb ozone adsorbed in the oxygen recycling facility 4. After that, the desorbed ozone and compressed air are supplied via a supply ozone header pipe 11b (hereinafter also referred to as a fourth shared pipe 11b) to a plurality of air diffusers 51a, 51b, 51c, and 51d provided in the ozone contact tank 5 storing the treated water 50. The supply ozone header pipe 11b is shared by the air diffusers 51a to 51d.

[0017] Here, the functions of the above four types of header pipes (compressed air header pipe 11a, oxygen header pipe 10a, ozonized oxygen header pipe 10b, and supply ozone header pipe 11b, in order from the left in FIG. 1) will be described in detail below.

[0018] First, the compressed air header pipe 11a serves as a circuit for supplying compressed air from the compressed air supply facility to the oxygen supply facility and for supplying compressed air to the adsorption tower (hereinafter also referred to as the adsorption device) of the oxygen recycling facility to desorb ozone adsorbed in the adsorption device. The oxygen header pipe serves as a circuit for supplying oxygen from the oxygen supply facility to the ozone generator and for returning oxygen recovered in the oxygen recycling facility to the ozone generator inlet. The ozonized-oxygen header pipe serves as a circuit for supplying ozonized oxygen (ozone and oxygen) from each ozone generator to a common (shared) oxygen recycling facility. Finally, the supply ozone header pipe serves as a circuit for supplying desorbed ozonized air (ozone and compressed air) from the oxygen recycling facility to the ozone contact tank.

[0019] Each header pipe, such as an oxygen header pipe, is connected in parallel to multiple pieces of equipment with the same name, but the pressure differences between the pieces of equipment with the same name are averaged, and the time required for this averaging is negligible in the present disclosure.

[0020] The ozone contact tank is a tank where ozone gas and treated water are brought into contact with each other and reacted. The ozone generator is equipped with a power supply, and the inverter of this power supply can adjust the ozone generation concentration. Furthermore, the adsorption performance is monitored by the oxygen concentration at the outlet of the adsorption tower. If the oxygen concentration drops, for example, it is determined that there is a "possible malfunction." A detection device is also installed to prevent gas leaks.

[0021] Next, the oxygen recycling facility 4 will be described in more detail with reference to Fig. 2. Fig. 2 shows in detail the internal configuration of the oxygen recycling facility 4 in the treatment system diagram of the ozone supplying apparatus according to the first embodiment shown in Fig. 1.

[0022] As shown within the dotted line frame in FIG. 2 , the oxygen recycling facility 4 is composed of a NOx removal device 40, a plurality of adsorption towers 41 a and 41 b each having an ozone adsorption function and an ozone desorption function, an oxygen transfer device 42 to which oxygen is transferred from these adsorption towers 41 a and 41 b, a cooler 45 that removes the heat of compression of the oxygen gas whose temperature has been increased by adiabatic compression, a decompression mechanism 43 (specifically, a vacuum blower, for example) that decompresses and transfers the compressed air transferred to the adsorption towers 41 a and 41 b and the ozone desorbed in the adsorption towers 41 a and 41 b to the ozone contact tank 5 via the supply ozone header pipe 11 b, and an ozone buffer device 44.

[0023] Here, ozone and oxygen transferred from the ozone generator through the ozonized-oxygen header pipe 10b are separately supplied to the adsorption towers 41a and 41b, and after the ozone is adsorbed by the ozone adsorbent provided therein, the separated oxygen is transferred to the oxygen transfer device 42. The ozone buffer device 44 has the function of suppressing fluctuations in the concentration of ozone supplied to the ozone contact tank.

[0024] In FIG. 2, ozone and oxygen are completely separated by the ozone adsorbent provided in the adsorption tower 41a or 41b, and therefore the oxygen separated in the adsorption tower 41a or 41b is entirely recycled as a raw material for the ozone generator.

[0025] 2, the basic role of the cooler 45 is to prevent thermal decomposition of ozone in the ozone generator due to the temperature of the oxygen gas being handled rising to approximately 100° C., and prevents thermal decomposition by cooling the temperature of the gas that has risen to about 40° C. Without this cooler 45, high-temperature oxygen gas would be supplied to the ozone generator, raising the concern that the generated ozone would be thermally decomposed.

[0026] Next, gas transfer during ozone adsorption in the oxygen recycle facility 4 will be systematically explained in detail using FIG. 3, and gas transfer during ozone desorption in the oxygen recycle facility 4 will be systematically explained in detail using FIG. 4.

[0027] First, gas transfer during ozone adsorption in the oxygen recycling facility 4 will be described with reference to Figure 3. In Figure 3, the area enclosed by a dashed-dotted line frame corresponds to the above-mentioned oxygen recycling facility 4. The ozone and oxygen discharged from the ozonation-oxygen header pipe 10b are transferred from the NOx removal device 40 to the adsorption tower 41a or 41b for adsorbing ozone, and after the ozone is adsorbed in these adsorption devices, the separated oxygen passes through the oxygen transfer device 42, cooler 45, and then passes through the oxygen header pipe 10a to be supplied to each of the ozone generators 3a to 3c, where it is recycled.

[0028] Next, gas transfer during ozone desorption in the oxygen recycle system 4 will be systematically described with reference to Figure 4. In Figure 4, the area enclosed by a dashed-dotted line corresponds to the oxygen recycle system 4. Compressed air supplied from a plurality of compressed air supply systems is collected in a compressed air header pipe 11a and then passed through an adsorption tower 41a or an adsorption tower 41b by a pressure reduction mechanism 43. Meanwhile, the ozone adsorbed in the adsorption tower 41a or an adsorption tower 41b is desorbed and, together with the compressed air, passes through the pressure reduction mechanism 43, which is a vacuum blower, and an ozone buffer device 44 from the adsorption tower 41a or the adsorption tower 41b, before being transferred to the ozone contact tank 5 via the supply ozone header pipe.

[0029] As described above, according to the ozone supplying apparatus of the first embodiment, by configuring the apparatus so that the equipment for separating or transporting oxygen can be shared, the load or availability of the oxygen recycling equipment can be increased even when operating with a low ozone injection amount, thereby improving energy savings through oxygen recovery. Furthermore, by sharing the oxygen recycling equipment, the ozone supplying apparatus can be simplified, and the equipment introduction cost, maintenance cost, and installation space can be reduced, thereby improving investment effectiveness.

[0030] Furthermore, in the case of a large-scale water purification plant where multiple ozone generators with a capacity of 10 kg / h or more are installed, it is possible to reduce costs or facility space by approximately 30%.

[0031] Embodiment 2 An ozone supplying device according to embodiment 2 will be described below with reference to Figures 5 and 6. The ozone supplying device according to embodiment 2 differs from the ozone supplying device according to embodiment 1 in that the oxygen recycling facility 4 includes a control device for controlling a plurality of components arranged inside and outside the facility, and signal lines connecting this control device to each component (signal lines for sending signals from the control device to each component, and signal lines for sending signals from each component to the control device).

[0032] In addition to the piping connecting the multiple units for separating and transporting oxygen, the system also includes a piping branching from the ozonated-oxygen header pipe 10b and directly connecting to the supply ozone header pipe 11b (hereinafter referred to as the bypass piping), and a bypass valve 31 for controlling (opening and closing) the gas flow in the bypass piping 30. Another difference is that the piping connecting the ozonated-oxygen header pipe 10b (hereinafter also referred to as the second shared piping 10b) to the adsorption towers 41a and 41b includes an adsorption tower inlet valve 21 for controlling (opening and closing) the gas flow in the piping connecting the ozonated-oxygen header pipe 10b (hereinafter also referred to as the second shared piping 10b) to the adsorption towers 41a and 41b, and that ozone concentration meters 46a, 46b, and 46c are installed at the outlet sides of the ozone generators (see FIG. 5 ). The second shared piping 10b is shared between the inlets of the adsorption units, which supply the mixed gas to the adsorption units, and the outlets of the ozone generators, which discharge the mixed gas from the ozone generators.

[0033] Next, the configuration of the ozone supplying apparatus according to the second embodiment will be described in more detail below with reference to FIG. 5, focusing on the control device 6, which is a difference from the ozone supplying apparatus according to the first embodiment.

[0034] As shown in Fig. 5, the control device 6 is a component of the oxygen recycling facility 4. The control device 6 receives signals from the oxygen transfer device 42, which is another component other than the device itself, via signal line 61d, and from the pressure reducing mechanism 43 via signal line 61e. The control device 6 also receives signals from ozone concentration meters 46a to 46c, which are installed on the outlet sides of the ozone generators 3a to 3c, which are other components of the ozone supply device than the oxygen recycling facility 4, via signal lines 61a, 61b, and 61c corresponding to each concentration meter.

[0035] On the other hand, the control device 6 transmits a signal to the adsorption tower inlet valve 21 via a signal line 60g and to the bypass valve 31 via a signal line 60h. Furthermore, signals are transmitted to the oxygen supply facilities 2a to 2c via signal lines 60d to 60f, respectively, and to the ozone generators 3a to 3c via signal lines 60a to 60c, respectively.

[0036] If an abnormality occurs in the oxygen separation and transfer equipment, the ozone generator is operated at a lower airflow rate than its rated airflow rate (here, the rated airflow rate is defined as the rated ozone generation rate / rated ozone concentration per ozone generator). This rate can be adjusted using an inverter or other device. Abnormalities are detected by the oxygen transfer device and pressure reduction mechanism. Each of these mechanisms is equipped with an inverter, and the abnormality is detected based on the speed, current, torque, power consumption, etc. of the driving motor.

[0037] The rated airflow rate of the ozone generator can be adjusted by controlling the number of oxygen supply units or by operating the oxygen supply unit using an inverter to adjust the oxygen airflow rate supplied to the ozone generator.

[0038] Next, how to adjust the oxygen flow rate supplied to the ozone generator by the oxygen supply equipment when an abnormality occurs will be specifically explained below with reference to FIG. 6 based on the adjustment method and the adjustment amount.

[0039] FIG. 6 is a flowchart illustrating the operation (operating method) of the ozone supplying apparatus when the control device receives a failure signal via a signal line from the oxygen transfer device 42 or the pressure reduction mechanism 43, which are facilities for separating and transferring oxygen.

[0040] First, when the control device 6 receives a failure signal from the oxygen transfer device 42 via the signal line 61d or from the pressure reduction mechanism 43 via the signal line 61e (step S1), the control device 6 transmits a close signal to the adsorption tower inlet valve 21 and an open signal to the bypass valve 31 (step S2; see FIG. 5).

[0041] Next, the control device 6 transmits an output increase signal to the ozone generator via signal lines 60a, 60b, and 60c (step S3; see FIG. 5). At this time, the amount of increase is given as a command value, which is given by multiplying the rated ozone concentration by z. Here, z is the output increase rate relative to the rated concentration of the ozone generator. The value of z is usually set within the range of 1<z≦1.5 and is determined to an appropriate value depending on the abnormality status of the device. The upper limit of z is determined based on the ozone concentration that the ozone generator can output.

[0042] Finally, the control device 6 issues an output reduction signal to the oxygen supply equipment 2a, 2b, and 2c via signal lines 60d, 60e, and 60f, respectively (step S4; see FIG. 5). At this time, the amount to be increased is given as a command value, which is given by dividing the rated ozone concentration by z, where z is the same as that described above (details will not be repeated here).

[0043] As described above, according to the ozone supplying apparatus of the second embodiment, even if the shared equipment for separating or transporting oxygen breaks down, the apparatus is configured to be able to operate the equipment as a bypass, thereby preventing the supply of ozone to the ozone contact tank from being stopped, thereby improving the reliability of the ozone supplying apparatus and stabilizing the quality of the treated water.

[0044] Furthermore, during normal operation, oxygen can be reused, so there is no need to supply an oxygen flow rate corresponding to the rated airflow rate of the ozone generator from the oxygen supply equipment. Furthermore, in the event of a breakdown in the oxygen separation or transport equipment, oxygen cannot be reused, so an oxygen flow rate corresponding to the rated airflow rate of the ozone generator must be supplied from the oxygen supply equipment. Conventionally, however, oxygen supply equipment has been provided with a capacity equivalent to the rated airflow rate of the ozone generator as a backup in the event of a breakdown. In contrast, the ozone supply device of the second embodiment can operate at an airflow rate lower than the rated airflow rate of the ozone generator in the event of a breakdown, which is expected to reduce the introduction cost of the oxygen supply equipment or to save energy during operation in the event of a breakdown.

[0045] Furthermore, in the event of an abnormality in the oxygen separation or transport equipment, the capacity of the oxygen supply equipment can be reduced by operating at a generated ozone concentration higher than the rated ozone concentration. For example, as mentioned above, since the maximum value of z is 1.5 (which indicates that the generated ozone concentration can be increased to 1.5 times the rated generated ozone concentration in the event of a malfunction), it can be seen that in the event of a malfunction, the oxygen flow rate supplied from the oxygen supply equipment to the ozone generator can be reduced to approximately 0.67 times the rated flow rate. In other words, a reduction of more than 30% in the capacity of the oxygen supply equipment can be expected. However, care must be taken because the power consumption of the ozone generator increases as the generated ozone concentration increases.

[0046] Embodiment 3 An ozone supplying apparatus according to embodiment 3 will be described below with reference to Figures 7 and 8. The ozone supplying apparatus according to embodiment 3 differs from the ozone supplying apparatus according to embodiment 2 in that it further includes an oxygen concentration meter 47 (hereinafter also simply referred to as concentration meter 47) (see Figure 7). This oxygen concentration meter 47 is provided to measure the oxygen concentration at the outlet position of the adsorption apparatus, and if there is an abnormality in the oxygen concentration, an abnormality signal is transmitted to the control device 6 via a signal line 61f.

[0047] Next, the operation (operation method) of the ozone supplying apparatus according to the third embodiment when a failure or abnormality occurs in the ozone supplying apparatus will be described with reference to the flow chart shown in FIG.

[0048] First, when the control device 6 receives a fault signal from the oxygen transfer device 42 via signal line 61d or from the pressure reducing mechanism 43 via signal line 61e, or receives an abnormal signal indicating the oxygen concentration at the adsorption tower outlet via signal line 61f from the oxygen concentration meter 47 (step S5), the control device 6 transmits a close signal to the adsorption tower inlet valve 21 and an open signal to the bypass valve 31 (step S2; see FIG. 6 ). The operations subsequent to the above (steps S3 and S4) and the symbol z in the figure are the same as those described in the operation of the ozone supply device according to the second embodiment, and therefore will not be described here. Since only ozone is used for the reaction in the ozone contact tank, the presence of oxygen in the ozone does not pose a problem.

[0049] As described above, according to the ozone supplying apparatus of the third embodiment, it is possible to detect not only a fault signal of the shared equipment for separating or transporting oxygen, but also an abnormality of the adsorption apparatus, which is the equipment for separating oxygen, from the oxygen concentration.

[0050] While various exemplary embodiments and examples are described herein, the various features, aspects, and functions described in one or more embodiments are not limited to specific embodiments and may be applied to the embodiments individually or in various combinations. Therefore, countless variations not illustrated are contemplated within the scope of the technology disclosed herein. For example, this includes modifying, adding, or omitting at least one component, or even extracting at least one component and combining it with components from other embodiments. Specifically, in the above description, signals exchanged with the control device are described as having different functions for transmission and reception, and are assigned different reference numerals according to their respective functions. However, this is not limited to this. If the components of the ozone supply device that is the destination and destination of the control device are the same, the same physical signal line can perform both transmission and reception, and therefore the same reference numeral may be used. Furthermore, while the signal line is described as being wired, this is not a limitation and the signal line may be wireless.

[0051] DESCRIPTION OF SYMBOLS 1a, 1b, 1c compressed air supply equipment, 2a, 2b, 2c oxygen supply equipment, 3a, 3b, 3c ozone generator, 4 oxygen recycling equipment, 5 ozone contact tank, 10a first shared piping (oxygen header pipe), 10b second shared piping (ozonated oxygen header pipe), 11a third shared piping (compressed air header pipe), 11b fourth shared piping (supply ozone header pipe), 21 adsorption tower inlet valve, 30 bypass piping, 31 bypass valve, 40 NOx removal device, 41a, 41b adsorption tower (adsorption device), 42 oxygen transfer device (blower), 43 pressure reduction mechanism (vacuum blower), 44 ozone buffer device, 45 cooler, 46a, 46b, 46c ozone concentration meter, 47 oxygen concentration meter, 50 treated water, 51a to 51d air diffuser, 60a to 60h Signal lines (transmission signal lines from the control device), 61a to 61e signal lines (reception signal lines of the control device)

Claims

1. An ozone supply system comprising: a plurality of ozone generators that generate ozone from oxygen; adsorption devices, the number of which is less than the total number of the ozone generators, that separate oxygen contained in a mixed gas composed of oxygen and the ozone and supplied from the ozone generators by adsorbing the ozone; oxygen transfer devices, the number of which is less than the total number of the ozone generators, that transfer the oxygen separated from the mixed gas by the adsorption devices to the ozone generators; a first shared pipe that connects, in common, an outlet side of the oxygen transfer device from which oxygen is delivered, to an inlet side of the ozone generator to which oxygen is delivered; and a second shared pipe that connects, in common, an inlet side of the adsorption device to which the mixed gas is delivered, to an outlet side of the ozone generator to which the mixed gas is delivered.

2. The ozone supply device according to claim 1, characterized in that it comprises: a bypass pipe branching off from the second shared pipe and connected via a shared pipe separate from the first shared pipe and the second shared pipe to an ozone contact tank to which the ozone and compressed air are supplied and which brings the stored treated water into contact with the ozone; an adsorption tower inlet valve installed in a piping path connected to the second shared pipe and located on the inlet side of the adsorption device; a bypass valve installed in the path of the bypass piping; and a control device having signal lines individually connected to the adsorption device and the oxygen transfer device, and which opens and closes the adsorption tower inlet valve and the bypass valve based on signals transmitted from the adsorption device and the oxygen transfer device via the respective signal lines.

3. The ozone supply device according to claim 1 or 2, characterized in that a cooler for cooling gas passing through the piping installed to transport the separated oxygen from the adsorption device to the first common piping is provided in the path of the piping.

4. The ozone supply device according to claim 2, characterized in that a concentration meter for measuring oxygen concentration is provided in the path of a pipe installed to transport the separated oxygen from the adsorption device to the first common pipe.

5. A plurality of ozone generators that generate ozone from oxygen; adsorption devices that are composed of oxygen and the ozone and that separate the oxygen contained in the mixed gas supplied from the ozone generators by adsorbing the ozone; oxygen transfer devices that transfer the oxygen separated from the mixed gas by the adsorption devices to the ozone generators and that are fewer in number than the total number of the ozone generators; a first shared pipe that connects the outlet side of the oxygen transfer device from which oxygen is delivered to the inlet side of the ozone generator to which oxygen is delivered; a second shared pipe that connects the inlet side of the adsorption device to which the mixed gas is delivered to the outlet side of the ozone generator to which the mixed gas is delivered; a bypass pipe branching off from the second shared pipe and connected via a shared pipe separate from the first and second shared pipes to an ozone contact tank to which the ozone and compressed air are supplied and which brings the ozone into contact with stored treated water for reaction; an adsorption tower inlet valve installed in a piping path that is connected to the second common piping and arranged on the inlet side of the adsorption unit; a bypass valve installed in a bypass piping path; and a control device having signal lines individually connected to the adsorption unit and the oxygen transfer unit, and which opens and closes the adsorption tower inlet valve and the bypass valve based on signals transmitted from the adsorption unit and the oxygen transfer unit via the respective signal lines, wherein, when an abnormality occurs in the adsorption unit or the oxygen transfer unit, the output of an oxygen supply facility that supplies oxygen to the ozone generator is operated at a lower output than a rated air volume of the ozone generator determined by the ratio of the rated ozone generation amount of the ozone generator to the rated ozone concentration of the ozone generator, and the mixed gas is supplied directly from the ozone generator to the ozone contact tank via the bypass piping without passing through the adsorption unit or the oxygen transfer unit.

6. The method for operating an ozone supplying apparatus according to claim 5, characterized in that the ozone generator is operated at an ozone concentration higher than a rated ozone concentration.

7. A method for operating an ozone supplying apparatus according to claim 5 or 6, characterized in that, when the measurement value of a concentration meter provided in a piping route for transporting the separated oxygen from the adsorption apparatus to the first common piping is equal to or less than a predetermined set value, it is determined that there is an abnormality in the adsorption apparatus, the adsorption tower inlet valve is closed and the bypass valve is opened to bypass the transfer of gas to the adsorption apparatus or the oxygen transfer apparatus, and the mixed gas supplied from the ozone generator is directly supplied to the ozone contact tank.

Images