JP4308474B2 - Hydrothermal reactor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention provides a hydrothermal reactor.In placeIn more detail, the hydrothermal reaction device is configured so that the reactor is not contaminated by the liquid to be treated when the hydrothermal reaction device is shut down.In placeEspecially suitable for supercritical water oxidation equipment for PCBsIn placeIt is related.
[0002]
[Prior art]
  With increasing awareness of the environment, liquids to be treated containing harmful wastes, particularly liquids to be treated containing harmful and hardly decomposable organic substances, are required to be completely decomposed and discharged.
  Therefore, high-temperature high-pressure water, for example, temperature 180℃As described above, attempts have been made to apply the hydrothermal oxidation reaction using hot water having a pressure of 1 MPa or more to the treatment of the liquid to be treated.
[0003]
Among hydrothermal oxidation reactions, a supercritical water oxidation reaction that has a high ability to oxidatively decompose organic substances using the high reactivity of supercritical water has attracted attention.
In the supercritical water oxidation reaction, harmful and hardly decomposable organic substances that were difficult to be decomposed by the prior art, such as PCB (polychlorinated biphenyl), dioxin, organochlorine solvents, etc. are oxidized and decomposed to produce carbon dioxide, It can be converted into harmless products such as nitrogen, water and inorganic salts.
[0004]
The supercritical water oxidation reaction is a reaction that decomposes organic substances using the high reactivity of supercritical water. For example, oxidative decomposition of difficult-to-decompose harmful organic substances is converted into harmless carbon dioxide and water. In order to decompose difficult-to-decompose high-molecular compounds and convert them into useful low-molecular compounds, their practical application is currently being actively studied.
Supercritical water refers to water in a supercritical state, that is, water in a state exceeding the critical point of water, and more specifically, at a temperature of 374.1 ° C. or higher and a pressure of 22.04 MPa or higher. Says water in a certain state. Supercritical water has a high ability to dissolve organic substances, and can completely dissolve non-polar substances that are abundant in organic compounds. Conversely, the ability to dissolve inorganic substances such as metals and salts is extremely low. Supercritical water can be mixed with a gas such as oxygen or nitrogen at an arbitrary ratio to form a single phase.
[0005]
  Here, as one of the hydrothermal oxidation reactors,7The basic configuration of a supercritical water oxidation apparatus that decomposes a liquid to be treated containing an organic chlorine compound such as PCB or dioxin by supercritical water oxidation will be described. Figure7Is a flow sheet showing the configuration of a conventional supercritical water oxidation apparatus.
  The supercritical water oxidation apparatus 10 is an apparatus for treating a liquid to be treated containing an organic chlorine compound by supercritical water oxidation in the presence of supercritical water.7As shown in FIG. 2, a vertical pressure-resistant sealed reactor 12 is provided as a reactor for performing a supercritical water oxidation reaction.
[0006]
  The supercritical water oxidation apparatus 10 serves as a supply system for supplying a reaction liquid to the reactor 12 through a liquid pipe 14 to be processed as a supply system for supplying a reaction material to be supplied to the reactor 12 for the supercritical water oxidation reaction. And an air compressor 20 that feeds air as an oxidant into the reactor 12 through the air supply pipe 18. Figure7Reference numeral 15 denotes an open / close valve provided immediately downstream on the discharge side of the liquid pump 16 to be processed as a main valve of the liquid pipe 14 to be processed. The on-off valve 15 may be a check valve.
  In addition, when the heat energy generated by the supercritical water oxidation reaction of the liquid to be treated is less than the energy necessary for maintaining the supercritical water oxidation reaction, auxiliary fuel is supplied to the reactor 12 and the inside of the reactor 12 is supplied. It is necessary to maintain the supercritical water oxidation reaction. For this purpose, an auxiliary fuel pump 24 for feeding auxiliary fuel into the reactor 12 through the auxiliary fuel supply pipe 22 is provided.
  Furthermore, a replenishment water pipe (not shown) for supplying make-up water or the like to the reactor 12 may be connected to the liquid pipe 14 to be treated.
[0007]
  In addition, the supercritical water oxidation apparatus 10 is a processing fluid system for flowing a processing fluid from the reactor 12 by injecting an alkaline aqueous solution into the processing fluid pipe 26 connected to the processing fluid outlet of the reactor 12. Neutralization quencher 28 for neutralization and quenching, cooler 30 for further cooling the processing fluid, pressure control valve 32 for controlling the pressure in the reactor 12, and gas-liquid separation of the processing fluid into a gas component and a liquid component A gas-liquid separator 34 is sequentially provided.
  A gas outflow pipe 36 through which the separated gas component flows out is connected to the upper part of the gas-liquid separator 34, and a liquid outflow pipe 38 through which the separated liquid component flows out is connected to the lower part.
  The neutralization quencher 28 injects an alkaline aqueous solution into the processing fluid to neutralize hydrochloric acid or the like generated from the organic chlorine compound in the liquid to be processed by supercritical water oxidation in the reactor 12 and cool the processing fluid. To do.
  Furthermore, the figure7As shown in FIG. 2, a cleaning liquid supply pipe 40 with an on-off valve 41 for injecting auxiliary fuel into the processing liquid pipe 14 is provided to clean the processing liquid pipe 14.
[0008]
  The liquid pipe 14 to be treated, the air supply pipe 18, and the auxiliary fuel supply pipe 22 communicate with the reactor 12 through a three-fluid nozzle 42.
  The three-fluid nozzle 42 is shown in FIG.8As shown in FIG. 2, the inner tube 44, a middle tube 48 provided outside the inner tube 44, and an outer tube 54 provided outside the middle tube 48 are configured as a triple tube body. The three-fluid nozzle 42 has an inner nozzle 46 provided at the tip of the inner tube 44 and an opening of the first annular portion 50 formed between the inner tube 44 and the middle tube 48. And an outer nozzle 58 provided at the tip of the outer tube 54 as an opening of a second annular portion 56 formed between the intermediate tube 48 and the outer tube 54.
  The front ends of the inner nozzle 46, the intermediate nozzle 52, and the outer nozzle 58 are circular openings.
[0009]
The liquid to be processed 14 is connected to the inner pipe 44, and the liquid to be processed that has flowed in from the liquid pipe 14 to be processed flows out from the inner nozzle 46 into the reactor 12. The auxiliary fuel supply pipe 22 is connected to the first annular portion 50, and the auxiliary fuel that has flowed from the auxiliary fuel supply pipe 22 flows out from the intermediate nozzle 52 into the reactor 12. The air supply pipe 18 is connected to the second annular portion 56, and the air flowing in from the air supply pipe 18 flows out from the outer nozzle 58 into the reactor 12 at a high speed.
The air flowing out from the outer nozzle 58 at a high speed atomizes the liquid to be treated flowing out from the inner nozzle 46 and the auxiliary fuel flowing out from the intermediate nozzle 52, and uniformly mixes and disperses them to each other to form a sprayed reactor 12. Let it flow into.
[0010]
  Further, as will be described later, instead of the three-fluid nozzle, an inner nozzle that allows the mixed fluid of the liquid to be processed and the auxiliary fuel to flow in, and an outer side that ejects the air that atomizes the mixed fluid of the liquid to be processed and the auxiliary fuel Some are provided with a two-fluid nozzle composed of a nozzle.
  Furthermore, the figure9As shown in FIG. 2, supercritical water of a type in which an air supply pipe 18 and an auxiliary fuel supply pipe 22 are connected to the liquid pipe 14 to be processed, and the liquid to be processed, air, and auxiliary fuel are fed into the reactor 12 as a mixed fluid. There is also an oxidizer 11.
  In the supercritical water oxidation apparatus 11, since the auxiliary fuel is used as the cleaning liquid for the liquid pipe 14 to be processed, the auxiliary fuel supply pipe 22 is covered immediately downstream of the on-off valve 15 that is the original valve of the liquid pipe 14 to be processed. It is connected to the processing liquid pipe 14.
[0011]
  Figure7When the PCB-water / emulsion is processed using IPA (Isopropyl Alcohol: isopropyl alcohol) as an auxiliary fuel using the above-mentioned supercritical water oxidation device 10 as shown in FIG. In order to prevent complete decomposition, the following procedure is used to perform IPA cleaning of the liquid pipe to be treated, and the supercritical water oxidation apparatus 10 is shut down.
(1) Gradually close the on-off valve 15 of the liquid tube 14 to be treated to gradually reduce the flow rate of PCB-water / emulsion (hereinafter simply referred to as PCB), while increasing the flow rate of IPA as auxiliary fuel. Then, the supercritical water oxidation reaction is maintained without changing the temperature of the reactor 12 by IPA. Instead of the operation using the on-off valve 15, the discharge flow rate itself of the liquid pump 16 to be processed may be reduced. The IPA flow rate can be increased by increasing the rotational speed of the auxiliary fuel pump 24 or by further increasing the opening degree of the open / close valve of the main valve (not shown) of the auxiliary fuel supply pipe 22. .
[0012]
(2) After stopping the liquid pump 16 to be processed, the on-off valve 15 is completely closed to stop the PCB supply. In the case where the on-off valve 15 is a check valve, it has a function as a check effect, so that the valve closing operation is not particularly performed (the same applies hereinafter).
(3) The state where only IPA is being sent to the reactor 12 is maintained for a predetermined time, for example, 1 to 240 minutes. In step (3), the on-off valve 41 is opened, IPA is injected from the cleaning liquid supply pipe 40, and IPA is fed into the reactor 12 while replacing the liquid to be processed in the liquid pipe 14 to be processed with IPA. To do.
(4) Stop the auxiliary fuel pump 24 to stop the IPA reactor feeding.
(5) The temperature of the reactor 12 is decreased by stopping the auxiliary fuel pump 24 and the pressure of the reactor 12 is decreased.
[0013]
  In addition, the supercritical water oxidation apparatus 10 described above.TheWhen the PCB is processed using IPA as an auxiliary fuel, when the supercritical water oxidation apparatus 10 is started, the following procedure is performed to prevent incomplete decomposition of the PCB.
(1) The air compressor 20 is started and air is sent to the reactor 12 to increase the pressure of the reactor 12.
(2) The hot makeup water is sent to the reactor 12 to raise the temperature of the reactor 12 to about 400 ° C.
(3) The auxiliary fuel pump 24 is started to send IPA into the reactor 12, and the reactor 12 is heated to the reaction temperature.
(4) The liquid pump 16 to be treated is started and the on-off valve 15 is opened (if the on-off valve 15 is a check valve, this operation is not necessary (the same applies hereinafter)), and the liquid to be treated is supplied to the reactor 12. And the IPA is switched to the liquid to be treated so as not to change the temperature of the reactor 12 by decreasing the flow rate of the IPA.
  Instead of the operation using the on-off valve 15, the discharge flow rate of the liquid pump 16 to be processed may be increased.
(5) The auxiliary fuel pump 24 is stopped and the supercritical water oxidation apparatus 10 is switched to steady operation.
  The operation start and operation stop of another conventional supercritical water oxidation apparatus 11 are substantially the same.
[0014]
The supercritical water oxidation apparatuses 10 and 11 can oxidize and decompose the organochlorine compound in the liquid to be treated almost completely to bring the concentration of the organochlorine compound in the treatment liquid to a reference value or less.
For example, when the PCBs and dioxins are processed, the supercritical water oxidation apparatuses 10 and 11 should set the PCB concentration of the processing solution to 3 μg / liter or less of the standard, and the dioxin concentration of the processing solution to 10 pgTEQ / liter or less of the standard. Can do.
[0015]
[Problems to be solved by the invention]
Conventionally, when the operation is stopped, PCB is washed away by IPA in step (3), washed, and replaced, but a small amount of PCB may remain in the replaced IPA. As a result, in step (4) and subsequent steps following step (3), contaminated IPA in the liquid pipe to be treated and further in the three-fluid nozzle in the reactor flows into or drops into the reactor whose temperature has dropped. In addition, harmful organochlorine compounds may be generated due to incomplete decomposition of PCB.
In the above description, the concern about the generation of harmful undegraded products when processing a harmful liquid to be treated was explained by taking the supercritical water oxidation treatment of PCB-water / emulsion as an example. However, the present invention is not limited to the above, and is a problem generally applicable to a hydrothermal reaction apparatus that processes a harmful liquid to be treated and a method of operating the hydrothermal reaction apparatus.
[0016]
  So bookIn the statementIn the case of shutdown, no undecomposed of harmful liquid to be treatedFor referenceHydrothermal reactor and operation method thereofIs described.
[0017]
Reference hydrothermal reactor
  To achieve the above objective,For referenceHydrothermal reactorIsA reaction liquid pump that feeds the liquid to be treated into the reactor through the liquid pipe to be treated connected to the reactor, and sends the liquid to the reactor by the liquid pump to react. In the hydrothermal reactor that treats the liquid to be treated by hydrothermal reaction in the vessel
  Provided with gas feeding means for feeding a flushing gas into a liquid pipe downstream of the liquid pump to be processed, when the operation of the hydrothermal reactor is stopped, the liquid pump is stopped or downstream of the liquid pump After closing the main valve of the liquid pipe to be treated and stopping the supply of the liquid to be treated to the reactor, the gas feeding means is started and the flushing gas is fed to the reactor through the liquid pipe to be treated. It is characterized by doing so.
[0018]
  Preferably, the gas for flushing is supplied by connecting a gas feeding means to the liquid pipe to be processed immediately downstream of the liquid pump to be processed or immediately downstream of the main valve provided in the liquid pipe to be processed downstream of the liquid pump to be processed. Introduce and flush the liquid pipes to be treated as wide as possible.
  Reference hydrothermal reactorThen, when the operation of the hydrothermal reactor is stopped, the liquid pump to be processed is stopped or the main valve provided in the liquid pipe to be processed downstream of the liquid pump to be processed is closed to supply the liquid to the reactor to be processed. After the supply is stopped, before the reaction temperature and reaction pressure of the reactor are reduced from the steady operating conditions by the process of injecting auxiliary fuel, the gas for flushing is sent to the reactor through the liquid tube to be treated by the gas feeding means. Then, by flushing the liquid tube to be processed, the liquid to be processed in the liquid tube to be processed or the fluid in which the liquid to be processed is replaced can be poured into the reactor.
  As a result, the liquid to be processed remaining in the liquid pipe to be processed or the liquid to be processed dissolved in the fluid replacing the liquid to be processed flows into the reactor as a result, and the liquid to be processed is in an undecomposed state. To prevent the possibility that it will occur in conventional hydrothermal reactors that flow out together with the process fluid or stop in the middle of the supercritical hydroxylation reaction and are converted into harmful intermediates and flow out with the processing fluid. be able to.
[0019]
First reference driving method
  First reference driving methodIs a method of operating a hydrothermal reactor that feeds the liquid to be treated into the reactor and treats the liquid to be treated by a hydrothermal reaction in the reactor, and when the hydrothermal reactor is shut down,
  Reaction of the liquid to be treated is stopped by stopping the liquid pump to be treated for feeding the liquid to be treated or by closing the main valve provided in the liquid pipe for liquid to be fed to the reactor. Stopping the supply to the vessel;
  A step of feeding the flushing gas into the reactor through the liquid tube to be treated by gas feeding means for feeding the flushing gas into the liquid tube to be treated;
  It is characterized by having.
[0020]
Second reference driving method
  Second reference driving methodIs a method of operating a hydrothermal reactor in which a liquid to be treated and auxiliary fuel are fed into a reactor, and the liquid to be treated is treated by a hydrothermal reaction in the reactor. When stopping,
  The liquid pipe to be processed which stops the liquid pump to be processed or sends the liquid to be processed to the reactor while increasing the flow rate of the auxiliary fuel so that the reaction temperature and reaction pressure of the reactor do not deviate from the steady operation conditions. Closing the main valve provided in the step, and stopping the supply of the liquid to be treated to the reactor;
  While adjusting the total flow rate of the auxiliary fuel so that the reaction temperature and reaction pressure of the reactor do not deviate from the steady operating conditions, the auxiliary fuel is fed into the liquid tube to be processed as a cleaning liquid, and the liquid to be processed in the liquid tube to be processed is Substituting with auxiliary fuel and washing the liquid pipe to be treated with auxiliary fuel;
  Before the reaction temperature and reaction pressure of the reactor drop from the steady operating conditions, the gas feeding means for feeding the flushing gas into the liquid tube to be treated is activated to react the flushing gas through the liquid tube to be treated. The step of sending it to the vessel,
  Stopping the auxiliary fuel delivery and lowering the reactor temperature;
  It is characterized by having.
[0021]
  First and secondReference drivingPreferably, in the method, flushing is performed by connecting a gas feeding means to the liquid pipe to be processed immediately downstream of the liquid pump to be processed or immediately downstream of the main valve provided in the liquid pipe to be processed downstream of the liquid pump to be processed. The working gas is introduced and the liquid pipes to be treated are flushed as wide as possible.
  Also the secondReference drivingWhen the liquid to be treated in the liquid pipe to be treated is replaced with auxiliary fuel by the method, and the liquid pipe to be treated is cleaned, the injection point of the auxiliary fuel for cleaning is immediately downstream of the liquid pump to be treated or the liquid pump to be treated. The liquid pipe to be processed is located immediately downstream of the original valve provided in the liquid pipe to be processed at the downstream, and the liquid pipe to be processed in a wide range as much as possible is replaced and cleaned. However, it is important that the flushing gas injection point is upstream of the auxiliary fuel injection point in order to flush the injected auxiliary fuel and remove the liquid to be treated dissolved in the auxiliary fuel.
[0022]
  First and secondReference drivingThe method involves flushing the liquid tube to be treated, or substituting the liquid to be treated with auxiliary fuel, and further flushing, before the reactor temperature and pressure drop from the steady operating conditions. The liquid to be treated or the fluid in which the liquid to be treated is replaced can be poured into the reactor.
  As a result, the liquid to be processed remaining in the liquid pipe to be processed or the liquid to be processed dissolved in the fluid that has replaced the liquid to be processed flows into the reactor as a result, and the liquid to be processed is processed in an undecomposed state. Prevents the occurrence of a conventional hydrothermal reactor that flows out together with the fluid, or that stops the progress of the decomposition reaction of the liquid to be treated and turns into a harmful intermediate and flows out along with the processing fluid. can do.
[0023]
  Reference hydrothermal reactor, And the first and secondReference drivingThe method is not limited to a hydrothermal reactor having a reactor provided with a two-fluid nozzle or a three-fluid nozzle, and an air supply pipe or an auxiliary fuel supply pipe is connected to a liquid pipe to be treated, and a fluid nozzle is not provided. The present invention can also be applied to a hydrothermal reaction apparatus in which a mixed fluid obtained by mixing a liquid to be treated and air, and further auxiliary fuel flows into the reactor. Further, the present invention can also be applied to a hydrothermal reactor in which a liquid pipe to be processed, an auxiliary fuel pipe, and an air supply pipe are individually connected to a reactor without using a two-fluid nozzle or a three-fluid nozzle.
  In particular,Reference hydrothermal reactorAnd the first and secondReference drivingIn the method, the hydrothermal reactor is a supercritical water oxidation device, the liquid to be treated is PCB-water / emulsion, the auxiliary fuel is IPA (Isopropyl Alchohol, isopropyl alcohol), and the flushing gas is an oxidation of the supercritical water oxidation reaction. The present invention can be suitably applied when the air is supplied as an agent.
[0024]
The present invention
  By the way, in order to eliminate the possibility of harmful substances flowing out from the reactor, it is possible to employ means for reliably closing the inlet of the liquid to be treated to the reactor.
[0025]
  Therefore, the present inventionProvides the following hydrothermal reactors 1 and 2.
1. A liquid to be treated; a liquid pipe for supplying a liquid to be processed to the reactor; an auxiliary fuel supply pipe for supplying auxiliary fuel to the reactor; and an air supply pipe for supplying air to the reactor. The pipe, the auxiliary fuel supply pipe, and the air supply pipe are hydrothermal reactors that communicate with the reactor via a three-fluid nozzle having a flow path connected to each pipe,
A hydrothermal reactor characterized in that an on-off valve capable of freely opening and closing the opening in the reactor of the liquid pipe to be treated is provided in the vicinity of the opening in the reactor.
2. A reactor, a liquid tube to be processed for supplying a mixed fluid of the liquid to be processed and auxiliary fuel to the reactor, and an air supply pipe for supplying air to the reactor; A hydrothermal reactor communicating with the reactor via a two-fluid nozzle having a flow path connected to each pipe;
A hydrothermal reactor characterized in that an on-off valve capable of freely opening and closing the opening in the reactor of the liquid pipe to be treated is provided in the vicinity of the opening in the reactor.
[0026]
  BookIn the invention, the on-off valve is provided at the opening in the reactor of the liquid tube to be processed, so that the inflow of the liquid to be processed can be freely controlled.
  Therefore, at the start of operation, before the reactor reaches the steady operation state, it is possible to prevent the liquid to be processed from flowing in and the liquid to be processed from flowing out of the reactor together with the processing fluid without being decomposed. .
  In addition, even when the operation is stopped, the reaction temperature and reaction pressure of the reactor are reduced from the steady operation conditions, and the liquid to be processed remaining in the liquid tube to be processed or the liquid to which the liquid to be processed is replaced is replaced. The processing liquid flows in and flows out with the processing fluid in a state where the processing liquid is not decomposed, or the progress of the decomposition reaction of the processing liquid stops halfway and is converted into a harmful intermediate, and flows out with the processing fluid. Thus, it is possible to prevent such a situation that has occurred in a conventional hydrothermal reactor.
[0027]
  Although the specification of the on-off valve is not limited as long as the opening in the reactor of the liquid pipe to be processed can be opened and closed, in the preferred embodiment of the present invention, the on-off valve freely opens and closes the opening in the reactor of the liquid pipe to be processed. Always open or close the valve body and reactor openingLikeAn urging means for urging the valve body, and moving the valve body upward or downward relative to the urging means to open or close the opening in the reactor. And a driving device for driving. The on-off valve is preferably of a normally closed type.
  Further, in a preferred embodiment, the opening in the reactor is formed in a nozzle shape, the on-off valve is a needle valve that opens and closes the nozzle tip opening, the urging means is a coil spring, and the drive device is a pneumatic cylinder.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, the present invention will be described in more detail based on exemplary embodiments with reference to the accompanying drawings.
Reference example of hydrothermal reactor
  BookreferenceAn example isFor referenceApplying hydrothermal reactor to supercritical water oxidation systemTaichiAn example is shown in FIG.referenceIt is a flow sheet which shows the composition of an example supercritical water oxidation apparatus.
  BookreferenceThe example supercritical water oxidation apparatus 60 has the same configuration as the conventional supercritical water oxidation apparatus except for the following.
  That is, bookreferenceAs shown in FIG. 1, in addition to the configuration of the conventional supercritical water oxidation apparatus 10, the supercritical water oxidation apparatus 60 of the example includes a liquid pipe 14 for flushing and a three-fluid nozzle 42 at the inlet of the reactor. In order to supply air, the flushing air supply pipe 62 is branched from the air supply pipe 18, immediately after the on-off valve 15 (the on-off valve may be a check valve) and at the junction of the cleaning liquid supply pipe 40. It is provided so as to merge with the liquid pipe 14 to be processed upstream.
  In the supercritical water oxidation apparatus 60, as described in the conventional supercritical water oxidation apparatus 10, the cleaning liquid supply pipe 40 branches from the auxiliary fuel supply pipe 22, and the liquid pipe 14 to be processed downstream of the on-off valve 15. It is connected to the. The cleaning liquid supply pipe 40 and the flushing air supply pipe 62 are provided with first and second on-off valves 41 and 64, respectively.
  BookreferenceIn the example, when the temperature of the reactor 12 is maintained at a predetermined temperature, the PCB in the liquid pipe 14 to be processed is replaced with IPA, and then the liquid to be processed is flushed while replacing the IPA with air. A small amount of PCB adhered to the pipe 14 and the like, PCB contained in IPA etc. adhered to the liquid tube 14 to be treated, etc. are completely fed into the reactor 12, and the three-fluid nozzle 42 is flushed. Thus, the portion of the three-fluid nozzle that ejects the liquid to be processed is dried.
  As a result, a trace amount of PCB is not mixed into the reactor 12 in the operation stop state as in the prior art. Therefore, the processing fluid flowing out from the reactor 12 is not contaminated with PCB.
[0029]
Reference operation method of hydrothermal reactor
  Bookhow to driveIswaterThermal reactorSecond referenceThe driving method described abovereferenceApplied to the supercritical waterTheIt is an example.
  When the PCB-water / emulsion is processed using the supercritical water oxidation apparatus 60 shown in FIG. 1 and IPA as an auxiliary fuel, the operation method of the supercritical water oxidation apparatus of the present example is as follows. Then, the supercritical water oxidation apparatus 60 is stopped.
[0030]
(1) Gradually close the on-off valve 15 which is the original valve of the liquid pipe 14 to be treated, or increase the IPA flow rate while decreasing the PCB flow rate by lowering the rotational speed of the liquid pump 16 to be treated. The temperature of the reactor is maintained at a predetermined temperature by the supercritical water oxidation reaction of the auxiliary fuel IPA. The flow rate of the auxiliary fuel IPA can be increased by increasing the rotational speed of the auxiliary fuel pump 24 or by further increasing the opening degree of the open / close valve (not shown) of the main valve of the auxiliary fuel supply pipe.
(2) After stopping the liquid pump 16 to be processed, the on-off valve 15 is completely closed to stop the PCB supply.
(3) The first on-off valve 41 is opened, and the cleaning IPA is supplied to the liquid pipe 14 to be treated, and this state is maintained for a predetermined time. While supplying the washing IPA, the flow rate of the auxiliary fuel IPA supplied from the auxiliary fuel supply pipe 22 to the reactor 12 is decreased, and the total flow rate of IPA flowing into the reactor 12 is made constant, so that the temperature of the reactor 12 is increased. Do not change.
[0031]
(4) The first on-off valve 41 is closed to stop the supply of the cleaning IPA in the liquid pipe 14 to be processed, and then the second on-off valve 64 is opened to supply flushing air to the liquid pipe 14 to be processed. Then, the liquid tube 14 to be treated is flushed. When stopping the washing IPA, the flow rate of the auxiliary fuel IPA is increased so that the total flow rate of IPA flowing into the reactor 12 is kept constant so that the temperature of the reactor does not change.
(5) After maintaining the step (4) for a predetermined time, the auxiliary fuel pump 24 is stopped and the supply of IPA is stopped.
(6) The temperature and pressure of the supercritical water oxidation apparatus 60 are reduced.
[0032]
  This exampleThen, when the temperature of the reactor 12 is maintained at a predetermined temperature, the PCB in the liquid tube 14 to be processed is replaced with IPA, and then flushing is performed while replacing the IPA with air. A small amount of PCB adhered to 14 etc. and PCB contained in IPA etc. adhering to the liquid pipe 14 to be treated are completely fed into the reactor 12 and the three-fluid nozzle 42 is flushed. The part which ejects the liquid to be processed in the three-fluid nozzle is brought into a dry state.
  As a result, a trace amount of PCB is not mixed into the reactor 12 in the operation stop state as in the prior art. Therefore, the processing fluid flowing out from the reactor 12 is not contaminated with PCB.
[0033]
Embodiment of hydrothermal reactor
  In this embodiment,BookFIG. 2 is an example of an embodiment in which the hydrothermal reaction apparatus according to the invention is applied to a supercritical water oxidation apparatus, FIG. 2 is a flow sheet showing the configuration of the supercritical water oxidation apparatus of this embodiment, and FIG. 3 is this embodiment. FIG. 4 is a longitudinal sectional view showing a configuration of a three-fluid nozzle provided as an inlet nozzle in a reactor of an example supercritical water oxidation apparatus, and FIG. 4 is a transverse sectional view taken along line II-II in FIG.
  The supercritical water oxidation apparatus 70 of the present embodiment has the same configuration as the conventional supercritical water oxidation apparatus 10 except that the configuration of the three-fluid nozzle 71 provided in the reactor 12 is different.
  The three-fluid nozzle 71 provided as the inlet nozzle of the reactor 12 drives the needle valve 72 and the needle valve 72 that open and close the inner nozzle 46 provided at the tip of the inner tube 44 as shown in FIGS. The three-fluid nozzle 42 is basically the same as the three-fluid nozzle 42 provided in the reactor 12 of the conventional supercritical water oxidation apparatus 10 except that the driving apparatus 73 is provided.
[0034]
The needle valve 72 has a valve pipe 74 and a triangular pyramid-shaped valve body 76 that can be closed by contacting the inner nozzle 46 at its lower end, and is driven by a drive device 73 to move up and down in the valve pipe 74. And a guide ring 80 fixed to the valve pipe 74 and slidably guiding the vertical movement of the valve rod 78 in the valve pipe 74.
The driving device 73 is provided at the lower end of the valve rod 78, and is provided between the pneumatic cylinder 82 that moves the valve rod 78 up and down, the piston plate 86, and the spring support plate 96, and is attached to lower the valve rod 78. And a coil spring 84 to be energized.
[0035]
The pneumatic cylinder 82 is configured as a part of the valve pipe 74, is fixed to the lower end of the valve stem 78, is slid onto the valve pipe 74, and is fixed to the valve pipe 74, and is moved up and down together with the valve stem 78. The spring support plate 96 is provided.
The pneumatic cylinder 82 raises the pressure in the cylinder 82 by causing air to flow into the cylinder 82 and pushes up the piston plate 86, and lowers the pressure in the cylinder 82 by letting air flow out of the cylinder 82. The piston plate 86 is pushed down by 84.
The coil spring 84 has an upper end fixed to the spring support plate 96 and a lower end fixed to the piston plate 86, and always transmits the extending force to the piston plate 86.
[0036]
With the above configuration, in the needle valve 72, the valve element 76 is always positioned above the nozzle opening of the inner nozzle 46 by the bias of the coil spring 84 and closes the nozzle opening of the inner nozzle 46.
When the air in the pneumatic cylinder 82 flows out, the needle valve 72 lowers the valve rod 78 while being guided by the guide ring 80 to bring the valve body 76 into line contact or surface contact with the nozzle opening of the inner nozzle 46. The inner nozzle 46 can be closed.
As the drive device, for example, a hydraulic cylinder such as a hydraulic cylinder or a hydraulic cylinder, or a solenoid can be used instead of the pneumatic cylinder.
[0037]
The three-fluid nozzle 71 is connected to the liquid pipe 14 to be processed, like the conventional three-fluid nozzle 42.
That is, the to-be-processed liquid pipe 14 is connected to the inner pipe 44, and the to-be-processed liquid flowing in from the to-be-processed liquid pipe 14 flows out from the inner nozzle 46 into the reactor 12. The auxiliary fuel supply pipe 22 is connected to the first annular portion 50, and the auxiliary fuel that has flowed from the auxiliary fuel supply pipe 22 flows out from the intermediate nozzle 52 into the reactor 12. The air supply pipe 18 is connected to the second annular portion 56, and the air flowing in from the air supply pipe 18 flows out from the outer nozzle 58 into the reactor 12 at a high speed.
The air flowing out from the outer nozzle 58 at a high speed atomizes the liquid to be treated flowing out from the inner nozzle 46 and the auxiliary fuel flowing out from the intermediate nozzle 52, and uniformly mixes and disperses them to each other to form a sprayed reactor 12. Let it flow into.
[0038]
Referring to FIG. 2, when the PCB-water / emulsion is processed using IPA as an auxiliary fuel using the supercritical water oxidation apparatus having the three-fluid nozzle of this embodiment, the super The operation procedure when stopping the critical water oxidation apparatus will be described.
(1) The on / off valve 15 which is the original valve of the liquid pipe 14 to be treated is gradually closed to decrease the flow rate of PCB, while increasing the flow rate of IPA, and the reactor by the supercritical water oxidation reaction of the auxiliary fuel IPA Is maintained at a predetermined temperature. The flow rate of the auxiliary fuel IPA can be increased by increasing the rotational speed of the auxiliary fuel pump 24 or by further increasing the opening degree of the open / close valve (not shown) of the main valve of the auxiliary fuel supply pipe.
[0039]
(2) After stopping the liquid pump 16 to be processed, the on-off valve 15 is completely closed to stop the supply of liquid to be processed.
(3) The needle valve 72 is closed.
(4) Stop the auxiliary fuel pump 24 to stop the supply of IPA to the liquid pipe 14 to be processed.
(5) The temperature and pressure of the supercritical water oxidation apparatus 70 are reduced.
[0040]
  Further, when the supercritical water oxidation apparatus 70 is started to operate, it is operated according to the following procedure.
(1) The air compressor 20 is started and air is sent to the reactor 12 to increase the pressure of the reactor 12.
(2) High temperature makeup water is sent to the reactor to raise the temperature of the reactor to about 400 ° C.
(3) The auxiliary fuel pump 24 is started to send IPA into the reactor 12, and the reactor 12 is heated to a predetermined reaction temperature.
(4) NeedleValve 7Open 2 and switch to steady operation.
(5) Open the on-off valve 15 and then start the liquid pump 16 to be processed to send the liquid to be processed to the reactor 12 and reduce the flow rate of IPA so that the temperature of the reactor 12 does not change. Then, the IPA is switched to the liquid to be processed.
[0041]
  In this embodiment, when the operation of the supercritical water oxidation apparatus 70 is stopped, the supply of PCB is stopped while the temperature of the reactor 12 is maintained at a predetermined temperature by IPA, and then three fluids are discharged by the needle valve 72. The inner nozzle 46 of the nozzle 71 is closed to completely shut off the reactor 12 and the liquid tube 14 to be processed. As a result, a trace amount of PCB is not mixed into the reactor in the shutdown state as in the prior art. Therefore, the fluid flowing out from the reactor does not become contaminated with PCB. When the operation of the supercritical water oxidation apparatus 70 is started, the inner nozzle 46 of the three-fluid nozzle 71 is closed by the needle valve 72, and the reactor 12, the liquid pipe 14 to be treated,CompleteIPA is supplied to the reactor 12 in a state of being completely shut off, and PCB is supplied after the temperature of the reactor 12 reaches a predetermined temperature by IPA. As a result, a trace amount of PCB is not mixed into the reactor in the shutdown state as in the prior art. Therefore, the fluid flowing out from the reactor does not become contaminated with PCB.
[0043]
Modification 1 of the embodiment
  In the three-fluid nozzle 94 of this modification,5As shown in FIG. 2, a coil spring 84 is provided at the lower portion of the pneumatic cylinder 82.
  The coil spring 84 that urges the valve rod 78 to descend is a compression spring, and has an upper end fixed to the piston plate 86 and a lower end attached to the guide ring 80. The upper end of the valve rod 78 is fixed to the piston plate 86 and moves up and down together with the valve rod 78 depending on the pressure in the pneumatic cylinder 82.
  When the cylinder pressure of the pneumatic cylinder 82 rises, the valve body 76 of the needle valve 72 descends against the extension force of the coil spring 84, and the inner nozzle 46 is closed. Conversely, when the pressure in the pneumatic cylinder 82 decreases, the valve body 76 of the needle valve 72 rises due to the extension force of the coil spring 84 and opens the inner nozzle 46.
[0044]
Modification 2 of the embodiment
The three-fluid nozzle 98 of this modification is shown in FIG.6As shown in FIG. 2, the needle valve 72 has an inverted triangular pyramid shaped valve body 100 at the lower end of the valve rod 78, pressurizes the pneumatic cylinder 82, and moves the valve rod 78 upward to open the nozzle opening of the inner nozzle 46. The inner nozzle 46 can be closed by bringing the valve body 100 into line contact or surface contact.
  The coil spring 84 is a compression spring that urges the valve rod 78 to move downward.6As shown in (a), the upper end is fixed to the spring support plate 96, and the lower end is attached to the piston plate 86 of the pneumatic cylinder 82. The upper end of the valve rod 78 is fixed to the piston plate 86 and moves up and down together with the valve rod 78 depending on the pressure in the pneumatic cylinder 82.
[0045]
  When the cylinder pressure of the pneumatic cylinder 82 is lowered, the piston rod 86 is lowered by the pressing force of the coil spring 84, the valve body 100 is separated from the inner nozzle 46, and the nozzle opening of the inner nozzle 46 is opened. Conversely, when the cylinder pressure of the pneumatic cylinder 82 rises, the valve rod 78 rises against the pressing force of the coil spring 84, and the valve body 100 contacts the inner nozzle 46 to close the nozzle opening.
  The vertical order of the coil spring 84 and the pneumatic cylinder 82 is shown in FIG.6As shown in (b), the three-fluid nozzle 98 may be reversed.
[0046]
  EmbodimentExampleThen, even if the needle valve provided on the inner nozzle of the three-fluid nozzle is provided on the inner nozzle of the two-fluid nozzle, the same effect can be obtained.
[0048]
  BookAccording to the invention, since the inflow of the liquid to be treated can be freely controlled by providing an opening / closing valve at the opening in the reactor of the liquid pipe to be treated, the temperature of the reactor and the When the pressure is lower than the steady-state operating condition, the liquid to be processed flows in, and the liquid to be processed flows out together with the processing fluid in an undecomposed state, or the progress of the supercritical water oxidation reaction of the liquid to be processed stops halfway. Into harmful intermediates and with the processing fluidLeakedThus, it is possible to prevent the occurrence of a problem that has occurred in a conventional hydrothermal reactor.
[Brief description of the drawings]
[Figure 1]Reference exampleIt is a flow sheet which shows the structure of this supercritical water oxidation apparatus.
FIG. 2 is a flow sheet showing a configuration of a supercritical water oxidation apparatus according to an embodiment.
FIG. 3 is a longitudinal sectional view showing a configuration of a three-fluid nozzle provided as an inlet nozzle of a reactor of a supercritical water oxidation apparatus according to an embodiment.
4 is a cross-sectional view of the three-fluid nozzle taken along line II-II in FIG.
FIG. 5ExampleModified example1It is sectional drawing which shows the structure of these 3 fluid nozzles.
[Figure66 (a) and 6 (b) respectively show the embodiment.ExampleModified example2It is sectional drawing which shows the structure of these 3 fluid nozzles.
[Figure7A flow sheet showing the configuration of a conventional supercritical water oxidation apparatus.
[Figure8It is a sectional view showing the structure of a three-fluid nozzle provided in a reactor of a conventional supercritical water oxidation apparatus.
[Figure9A flow sheet showing the configuration of another conventional supercritical water oxidation apparatus.
[Explanation of symbols]
10 Conventional supercritical water oxidation equipment
11 Another conventional supercritical water oxidation system
12 Vertical pressure-resistant sealed reactor
14 Liquid pipe to be treated
15 On-off valve
16 Liquid pump to be treated
18 Air supply pipe
20 Air compressor
22 Auxiliary fuel supply pipe
24 Auxiliary fuel pump
26 Processing fluid pipe
28 Neutralization quencher
30 Cooler
32 Pressure control valve
34 Gas-liquid separator
36 Gas outflow pipe
38 Liquid outflow pipe
40 Cleaning liquid supply pipe
41 On-off valve
42 Three-fluid nozzle
44 Inner pipe
46 Inner nozzle
48 Middle pipe
50 1st ring part
52 Intermediate nozzle
54 Outer pipe
56 Second annular part
58 Outer nozzle
60 Supercritical water oxidation apparatus of Embodiment 1
62 Air supply pipe for flushing
64 Second on-off valve
70 Supercritical water oxidation apparatus of Embodiment 2
71 3-fluid nozzle
72 Needle valve
73 Drive unit
74 Valve pipe
76 Disc
78 Valve stem
80 Guide ring
82 Pneumatic cylinder
84 Coil spring
86 Piston plate
88 fixedBoard
94 Modifications13 fluid nozzle
96 Spring support plate
98 variations23 fluid nozzle
100 Valve body with inverted triangular pyramid shape

Claims (4)

A liquid to be treated; a liquid pipe for supplying a liquid to be processed to the reactor; an auxiliary fuel supply pipe for supplying auxiliary fuel to the reactor; and an air supply pipe for supplying air to the reactor. The pipe, the auxiliary fuel supply pipe, and the air supply pipe are hydrothermal reactors that communicate with the reactor via a three-fluid nozzle having a flow path connected to each pipe,
  A hydrothermal reactor characterized in that an on-off valve capable of freely opening and closing the opening in the reactor of the liquid pipe to be treated is provided in the vicinity of the opening in the reactor. A reactor, a liquid tube to be processed for supplying a mixed fluid of the liquid to be processed and auxiliary fuel to the reactor, and an air supply pipe for supplying air to the reactor; A hydrothermal reactor communicating with the reactor via a two-fluid nozzle having a flow path connected to each pipe;
  A hydrothermal reactor characterized in that an on-off valve capable of freely opening and closing the opening in the reactor of the liquid pipe to be treated is provided in the vicinity of the opening in the reactor. The on-off valve freely opens and closes the opening in the reactor of the liquid tube to be treated, the urging means for urging the valve body so as to always open or close the opening in the reactor, and the urging means And a drive device for driving the valve body to move the valve body upward or downward relative to the opening in the reactor to open or close the opening in the reactor. Or the hydrothermal reaction apparatus of 2. 4. The reactor according to claim 3, wherein the opening in the reactor is formed in a nozzle shape, the on-off valve is a needle valve that opens and closes the nozzle tip opening, the urging means is a coil spring, and the driving device is a pneumatic cylinder. The hydrothermal reactor described.

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