JP2016019942A - Fluid processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid processing apparatus capable of reducing frequency of maintenance of a reaction tank while maintaining high processing efficiency, and reducing running costs and labor.SOLUTION: Inside a body 42 of a reaction tank, a cylindrical catalyst member 50 along the inner diameter of the reaction tank is arranged. The catalyst member 50 is constituted by stacking catalyst members 50a, 50b, 50c in a non-fixed state. Each of catalyst members 50a, 50b, 50c is formed by covering a substrate in which a corrugated plate has a cylindrical shape with a catalyst layer. Thereby, a surface area of the catalyst member 50 is larger than that of the reaction tank corresponding to the catalyst member, and catalyst performance is improved. Since there is space between the inner peripheral surface of the reaction tank and the catalyst member 50, heat of reaction generated in the surface of the catalyst member 50 is hardly moved through the reaction tank, compared to a configuration in which a catalyst is directed covered on the inner peripheral surface of the reaction tank. When the catalyst member is thermally expanded, distortion is absorbed in a bending part, and damage due to deformation of the catalyst member 50 is prevented.SELECTED DRAWING: Figure 3

Description

  The present invention treats a fluid to be treated (including the concept of purification) by mixing the fluid to be treated such as waste water with an oxidant and oxidizing and decomposing organic matter in the fluid to be treated under high temperature and high pressure conditions. More specifically, the present invention relates to a fluid processing apparatus that promotes oxidative decomposition using a catalyst.

Conventionally, it is a supercritical material that decomposes and renders harmless organic substances such as dioxins and PCBs (polychlorinated biphenyls), organic processing fluids such as human waste, sewage, livestock manure, and wastewater from food factories. Hydrolysis equipment is known.
For example, using a supercritical water and an oxidant, a hydrothermal oxidative decomposition treatment device or supercritical decomposition treatment that converts a process target fluid containing organic substances into an innocuous substance such as carbon dioxide, water, and inorganic salt by oxidizing it. An apparatus is known (Patent Documents 1 and 2).
In such an apparatus, typical reaction conditions are a pressure of 25 to 50 MPa and a temperature of about 500 to 700 ° C.

In such an apparatus, an apparatus configuration that can withstand high temperature and high pressure conditions of about 25 to 50 MPa and about 500 to 700 ° C. is necessary, and an increase in the size and cost of the processing system cannot be avoided.
There is also known an apparatus that promotes an oxidation reaction by bringing a fluid, which is heated to a temperature higher than the critical temperature of water and added with an oxidizing agent into high-temperature and high-pressure water having a pressure lower than the critical pressure of water, into contact with a catalyst in a reaction tank ( Patent Document 3).
According to the system using the above catalyst, even a hardly decomposable organic substance can be satisfactorily oxidatively decomposed at a relatively low temperature of about 250 to 500 ° C.
Since the treatment target fluid can be treated under conditions (for example, 0.5 to 20 MPa, 100 to 500 ° C.) that are milder than the reaction conditions of the supercritical water oxidation treatment apparatus, it contributes to the compactness and cost reduction of the treatment system.

As the arrangement method of the catalyst, as shown in FIG. 9 (a), a cylindrical reaction vessel 100 filled with a granular catalyst 102 in a mesh container or the like so as to intersect the fluid moving direction is used. A system is known in which the gap is moved in the axial direction (longitudinal direction) of the reaction tank while the fluid is in contact with the catalyst 102.
In this method, since the flow resistance is large and the processing efficiency is low, in order to cope with this, as shown in FIG. 9B, a catalyst layer (not shown) is provided inside and outside the reaction vessel 100, and the fluid is There is also known a system in which a honeycomb-structured catalyst 106 in which a plurality of tubes 104 extending in the moving direction are coupled is arranged.
In the catalyst having a honeycomb structure, since the fluid moves in each pipe, the flow resistance is small as compared with the method in which the granular catalyst is arranged.

By the way, the processing target fluid handled by this type of fluid processing apparatus often contains inorganic substances such as metals and salts (including the concept of inorganic solids; the same applies hereinafter), and these inorganic substances are contained in the reaction tank. It becomes a solid and precipitates.
Examples of inorganic substances include alumina, silica, zirconia, phosphate, nitrate, and sulfate.
Superheated steam and supercritical water have a high ability to dissolve organic substances, but have a low ability to dissolve inorganic substances.

In the reaction tank filled with the granular catalyst, the mixed fluid flows in the intergranular space formed between the individual catalysts.
Among the infinite number of granular catalysts filled in the reaction tank, inorganic solids are intensively fixed and deposited on the catalyst group located on the most upstream side in the fluid movement direction and grow.
Eventually, the deposit of inorganic solids clogs the intergranular space around the catalyst group located on the most upstream side.

In the catalyst having a honeycomb structure, as shown in FIG. 10A, since a plurality of tubular spaces are secured, clogging is less likely than in a system in which a granular catalyst is filled.
However, since the end face on the upstream side in the fluid movement direction is located at right angles to the fluid movement direction in the entire area of the catalyst, the inorganic solid material 110 is concentrated.
As shown in FIG. 10B, the deposit of the inorganic solid material 110 attached to the upstream end face grows toward the center of each opening.

When the openings are not so large, the plurality of openings are closed early, blocking the flow of the mixed fluid into the catalyst of the honeycomb structure.
In particular, when the oxidative decomposition treatment is performed under the condition where water is present as superheated steam, the density of the fluid is smaller than when it is present as a subcritical fluid, and it becomes difficult to push the fixed inorganic substance downstream.
That is, it is known that inorganic substances are easily deposited in the direction of gravity action.

When an inorganic substance accumulates in the reaction tank, it is necessary to clean the reaction tank.
Specifically, after the treatment reaction is stopped and cooled to room temperature, a process is required in which the worker opens the reaction tank and removes the inorganic substances fixed inside the reaction tank.
In particular, the smaller the inner diameter of the reaction vessel, the more frequently the inorganic material is deposited, and the more frequently the reaction vessel is maintained.

When the maintenance of the reaction tank needs to be performed frequently, the processing efficiency is lowered, the running cost is significantly increased, and a great deal of labor is imposed on the operator.
When the adhesion between the inorganic substance and the catalyst is large, it may be impossible to remove the inorganic substance in the reaction tank.
In such a case, the reaction tank can be regenerated by removing the catalyst layer to which the inorganic substance is fixed and providing a new catalyst layer. However, the running cost of the catalyst increases and the processing time is also increased. There is a problem that it requires.

Patent Document 4 discloses a reaction tube for a microreactor in which an inner peripheral surface is coated with a thin film of a catalyst.
The inner diameter of the reaction tube is defined as 1 mm or less.
According to the structure of this reaction tube, theoretically, the catalyst is located on the outer peripheral surface side of the flow path of the fluid to be treated, and therefore there is no factor for depositing an inorganic substance in the flow path.

The reason why the inner diameter of the microreactor reaction tube is defined as 1 mm or less is that, as described in “0002” of Patent Document 4, it is intended to obtain a prompt and highly efficient interface reaction. .
In the flow path having an inner diameter of 1 mm or less, since the ratio of the inner surface area (the area of the inner peripheral surface of the reaction tube) to the internal volume (the flow volume of the reaction tube) is large, almost all of the processing target fluid that has flowed into the reaction tube An interfacial reaction with the catalyst occurs.
In other words, since the inner diameter is too fine, almost all of the fluid to be treated is in contact with the catalyst at the same time.

However, in the configuration in which the inner wall of a tube having an inner diameter of 1 mm or less is coated and disposed, an inorganic substance that cannot be oxidatively decomposed may be deposited and fixed on the surface of the catalyst, thereby blocking the internal space (flow path) of the tube. is there.
For example, inorganic substances such as alumina, silica, zirconia, and phosphorus, which are part of the final product resulting from oxidative decomposition of organic substances, precipitate as solids, adhere to the catalyst, and increase the thickness in the radial direction of the tube. Block the road.
In order to avoid the blockage of the flow path by the inorganic substance and to increase the processing amount, a method of enlarging the reaction tube and enlarging the diameter can be considered.

However, when the reaction tube is increased in size, the surface area of the catalyst with respect to the workpiece flowing in per unit time decreases.
When the reaction tube is enlarged without changing the shape, the area in the tube increases in proportion to the square of the dimension, but the volume is proportional to the cube of the size, so a catalyst is required to promote the chemical reaction of the workpiece. There is a risk of insufficient area.
If the catalyst area is insufficient, the processing efficiency decreases.

  The present invention has been made in view of such a current situation, and can reduce the maintenance frequency of the reaction tank while maintaining good processing efficiency, and can contribute to reduction of running cost and labor. The main purpose is provision.

  In order to achieve the above object, the fluid processing apparatus of the present invention decomposes an organic substance in the processing target fluid by an oxidation reaction under a heated and pressurized state of a mixed fluid of the processing target fluid and an oxidizing agent, and performs the processing. A cylindrical reaction tank for treating the target fluid is provided, and a cylindrical catalyst member along the inner diameter of the reaction tank is disposed inside the reaction tank, and the surface area of the catalyst member is equal to that of the catalyst member. It has a shape larger than the corresponding surface area in the reaction vessel.

  According to the present invention, it is possible to reduce the maintenance frequency of the reaction tank while maintaining good processing efficiency, and it is possible to contribute to reduction of running cost and labor.

1 is a schematic configuration diagram of a fluid processing apparatus according to a first embodiment of the present invention. It is a general | schematic longitudinal cross-sectional view of a reaction tank. It is a perspective view of a catalyst member. FIG. 3 is a schematic sectional view taken along line XX in FIG. 2. It is a figure which shows the modification of a corrugated sheet shape. It is a top view of the catalyst member in a 2nd embodiment. It is a principal part perspective view of the catalyst member in 3rd Embodiment. It is a general | schematic longitudinal cross-sectional view of the reaction tank which shows arrangement | positioning of the catalyst member of the comparative example in the performance experiment of a catalyst member. It is a figure which shows the arrangement configuration of the catalyst in the conventional reaction tank, (a) is a general | schematic cross-sectional view which shows the arrangement configuration of a granular catalyst, (b) is a general | schematic cross-sectional view which shows the arrangement configuration of the catalyst of a honeycomb structure. . It is a principal part perspective view which shows the adhering state and the deposition state of the inorganic substance in the catalyst of a honeycomb structure.

Embodiments of the present invention will be described below with reference to the drawings.
1 to 4 show a first embodiment.
First, based on FIG. 1, the outline | summary of the whole structure of the fluid processing apparatus (processing system) which concerns on this embodiment is demonstrated.
The fluid processing apparatus 1 includes a processing target fluid supply unit 2, an oxidant supply unit 3, a reaction tank 4, a heat exchange unit 5, a solid separation unit 6, a gas-liquid separation unit 7, a control unit (not shown), and the like. It has.
Each configuration will be specifically described below.

The processing target fluid supply unit 2 includes a raw water tank 8, and the processing target fluid W containing organic substances is stored in the raw water tank 8 in an unprocessed state.
The processing target fluid W is agitated by the stirrer 9, whereby the suspended solids SS (Suspended solids) contained in the processing target fluid is evenly dispersed, and the organic substance concentration is made uniform.
The stirred target fluid W is pumped toward the reaction tank 4 by the raw water supply pump 10.
In the process in which the processing target fluid W is pumped, the raw water pressure gauge 11 detects the pressure and the raw water flow meter 12 detects the flow rate.

The flow rate of the processing target fluid W can be adjusted by the raw water inlet valve 13.
The raw water inlet valve 13 plays a role of a check valve, and allows the processing target fluid W sent from the raw water supply pump 10 to flow from the raw water supply pump 10 side to the reaction tank 4 side, but in the reverse direction. Block the flow of
The processing target fluid W that has passed through the raw water inlet valve 13 is preheated by the raw water preheater 14 serving as a heating means disposed so as to surround the flow path of the processing target fluid W.

The oxidant supply unit 3 includes an oxidant pressure feed pump 15 formed of a compressor.
The oxidant pump 15 pumps the air A taken as an oxidant toward the reaction tank 4 while compressing the air A to a pressure comparable to the pressure of the processing target fluid W.
In the process of pressure-feeding the air A, the pressure is detected by the oxidant pressure gauge 16 and the flow rate is detected by the oxidant flow meter 17.
The oxidant inlet valve 18 plays a role of a check valve, and allows the air A fed from the oxidant pressure feed pump 15 to flow from the oxidant pressure feed pump 15 side to the reaction tank 4 side. Block the reverse flow.
The air A that has passed through the oxidant inlet valve 18 is preheated by an oxidant preheater 20 serving as a heating means disposed so as to surround the flow path of the air A.

The processing target fluid W preheated by the raw water preheater 14 and the air A preheated by the oxidant preheater 20 merge and are put into the reaction tank 4 as a mixed fluid.
Therefore, the raw water preheater 14 is located on the upstream side in the charging direction of the processing target fluid W with respect to the reaction tank 4.
The pressure of the processing target fluid W and the pressure of the air A are adjusted so as to be substantially the same as the pressure in the reaction tank 4.
In FIG. 1, a route for mixing before entering the reaction tank 4 is used, but in reality, the fluid to be treated and the oxidant are introduced into the reaction tank 4 through separate paths to form a mixed fluid in the reaction tank.

The amount of air pumped by driving the oxidant pump 15 is determined based on the stoichiometric amount of oxygen necessary to completely oxidize the organic matter in the processing target fluid W.
More specifically, based on the TOC (Total Organic Carbon), Total Nitrogen (TN), Total Phosphorus (TP), etc. of the fluid to be treated, such as the organic substance concentration, nitrogen concentration, phosphorus concentration, etc. The amount of oxygen necessary for complete oxidation of the organic matter is calculated.
Based on the calculation result, the pumping amount of the air A is set.
Specifically, the oxygen amount is set to 1.0 to 3.0 times the amount of oxygen necessary for complete oxidation of the organic matter.
As the oxidizing agent, in addition to air, any one of oxygen, liquid oxygen, ozone, and hydrogen peroxide water, or a mixture of two or more of them can be used.

Examples of the pressure applied to the mixed fluid in the reaction tank 4 include a range of 0.5 to 30 MPa (desirably 5 to 15 MPa).
The pressure in the reaction tank 4 is adjusted by an outlet valve 34 described later. When the pressure in the reaction tank 4 becomes higher than the threshold value, the outlet valve 34 automatically opens the valve and discharges the mixed fluid in the reaction tank 4 to the outside, thereby maintaining the pressure in the reaction tank 4 near the threshold value. To do.

The mixed fluid in the reaction tank 4 is heated by heat generated by the oxidative decomposition of the organic matter.
When the processing target fluid W contains an organic substance at a high concentration, the mixed fluid may be heated to a desired temperature only with a large amount of heat generated when a large amount of the organic substance is oxidized and decomposed.
In this case, only when the apparatus is started up, the raw water preheater 14 and the oxidant preheater 20 are heated, and after the oxidative decomposition is started, the energization to these can be turned off.

Examples of the temperature of the mixed fluid in the reaction tank 4 include 100 to 600 ° C. (desirably 200 to 550 ° C.).
The temperature is adjusted by adjusting the outputs of the raw water preheater 14 and the oxidant preheater 20.

When temperature = 374.2 ° C. or higher and pressure = 22.1 MPa or higher are adopted as temperature and pressure conditions, the critical temperature and critical pressure of water are exceeded, and the critical temperature and critical pressure of air are also exceeded. State.
For this reason, the mixed fluid becomes a supercritical fluid having an intermediate property between liquid and gas.
In the supercritical fluid, the organic matter is well dissolved in the supercritical fluid and is in good contact with air, so that the oxidative decomposition of the organic matter proceeds rapidly.
As conditions of temperature and pressure, a temperature = 200 ° C. or higher (preferably 374.2 ° C. or higher), a pressure = less than 22.1 MPa (preferably 10 MPa or higher), a temperature below saturated steam, and a relatively high pressure. It is possible to adopt superheated steam as the processing target fluid in the mixed fluid in the reaction tank 4.
The temperature of the mixed fluid in the reaction vessel 4 is 100 to 700 ° C, desirably 200 to 550 ° C.

In the reaction tank 4, the mixed fluid is brought into a high temperature and high pressure state to promote oxidative decomposition of organic matter and ammonia nitrogen in the mixed fluid.
The mixed fluid that has moved to the end of the catalyst layer (described later) in the fluid conveyance direction (fluid movement direction) in the reaction tank 4 is in a state in which organic substances are almost completely oxidized and decomposed.

The treated fluid exiting from the reaction tank 4 flows into the heat exchanger 22 of the heat exchange unit 5.
A heat medium tank 23 is provided in the heat exchange unit 5, and a heat exchange fluid TF is stored in the heat medium tank 23.
The heat exchange fluid TF is supplied to the heat exchanger 22 by the heat exchange pump 24.
The heat exchange fluid heated through the heat exchanger 22 is sent to a heat energy utilization facility through a pipe (not shown).

A generator can be illustrated as an example of thermal energy utilization equipment.
In the generator, power generation is performed by rotating the turbine by an air flow generated when the heat exchange fluid whose pressure is increased by being heated is changed from a liquid to a gas state.
A part of the heat exchange fluid that has passed through the heat exchanger 22 may be fed by a branch pipe and used for preheating the processing target fluid W and the air A.

Since the processed fluid is deprived of heat by the heat exchanger 22, its moisture is cooled and the aspect changes from the supercritical state or the superheated vapor state to the liquid state, and enters the solid separation unit 6 in the liquid state.
On the other hand, the aspect of oxygen and nitrogen in the mixed fluid changes from a supercritical state to a gaseous state.

The solid separation unit 6 includes a first separation system 25 and a second separation system 26.
The first separation system 25 includes a first branch valve 27, a first separation filter 28, a first drain valve 29, and the like.
Similarly, the second separation system 26 includes a second branch valve 30, a second separation filter 31, a second drain valve 32, and the like.
The oxide as solid matter deposited in the reaction tank 4 is supplemented by the first separation filter 28 or the second separation filter 31.

The first separation system 25 and the second separation system 26 are used alternately.
That is, when the first separation system 25 is used, each valve of the second separation system 26 is closed, and when the second separation system 26 is used, each valve of the first separation system 25 is closed. It is done.
When the first separation filter 28 or the second separation filter 31 is clogged, the pressure measured by the outlet pressure gauge 33 changes. Based on this, the first separation filter 28 or the second separation filter 31 is washed or replaced. Done.

The gas-liquid separator 7 includes an outlet valve 34, a gas-liquid separator 35, and the like.
The mixed fluid that has passed through the solid separator 6 is separated into treated water and gas by the gas-liquid separator 35.
The composition of the gas separated by the gas-liquid separator 35 is detected by the gas chromatograph 36.

When an undecomposed substance is detected by the gas chromatograph 36, an alarm is issued in response to an output signal from the gas chromatograph 36.
The TOC concentration of the liquid separated by the gas-liquid separator 35 is detected by the TOC analyzer 37.
When the TOC analyzer 37 detects total organic carbon having a concentration exceeding the threshold value, an alarm is issued in response to an output signal from the TOC analyzer 37.

The treated water contains almost no suspended solids or organic matter because very low molecular weight organic matter that cannot be removed by biological treatment with activated sludge has been almost completely oxidized and decomposed.
Even as it is, it can be reused as industrial water depending on the application.
Further, if a filtration process using an ultrafiltration membrane is performed, it can be diverted to an LSI cleaning liquid or the like.
The gas separated by the gas-liquid separator 35 is mainly composed of carbon dioxide, nitrogen gas, and oxygen.

Immediately downstream of the heat exchanger 22, a heat exchanger outlet thermometer (not shown) for detecting the temperature of the liquid is provided.
The drive of the heat exchange pump 24 is controlled so that the detection result by the heat exchanger outlet thermometer is maintained within a predetermined numerical range.
Specifically, when the detection result by the heat exchanger outlet thermometer reaches a predetermined upper limit temperature, the drive amount of the heat exchange pump 24 is increased to increase the supply amount of the heat exchange fluid to the heat exchanger 22, The cooling function by the heat exchanger 22 is enhanced.
When the detection result of the heat exchanger outlet thermometer reaches a predetermined lower limit temperature, the amount of heat exchange fluid supplied to the heat exchanger 22 is reduced by reducing the drive amount of the heat exchange pump 24, and the heat exchanger 22 Reduce cooling function.

By controlling in this way, the amount of heat exchange can be adjusted appropriately and the temperature of the processed fluid can be maintained within a certain range.
The heat exchanger 22 may be directly attached to the reaction tank 4.

When the organic matter concentration in the processing target fluid W is relatively high, a large amount of heat is generated by oxidative decomposition of the organic matter.
For this reason, although the raw water preheater 14 and the oxidant preheater 20 are operated in the initial stage of operation, after the oxidative decomposition of the organic matter is started, the control is performed using the heat generated by the oxidative decomposition of the organic matter.
In other words, the temperature of the mixed fluid of the processing target fluid W and the air A may naturally rise to a desired temperature due to heat generated by oxidative decomposition of the organic matter.
When the detection result by the reaction vessel thermometer 38 that detects the temperature of the reaction vessel 4 is higher than a predetermined temperature, the control unit is configured to use the raw water preheater 14 and the oxidant preheater as heating means. Adjust 20 outputs.
Thereby, useless energy consumption can be suppressed.

It is good also as a structure which provides the heater which heats reaction tank itself on the outer surface of the reaction tank 4. FIG.
By heating the reaction tank, it is possible to suppress the heat transfer of the oxidation reaction heat generated in the reaction tank through the reaction tank, and thus the decrease in the heat exchange rate in the heat exchange section.

A raw water preheater 14, an oxidant preheater 20, a reaction tank thermometer 38, a raw water supply pump 10, and an oxidant pressure feed pump 15 are connected to the control unit.
The control unit is also equipped with a touch panel (not shown) as an operation / display device, which allows you to display the status of temperature, pressure, flow rate, etc., display warnings and details of malfunctions, and enter / change set values, etc. It has become.
When an abnormality occurs, interlock control is performed by driving the pump, turning off the heater, and closing the inlet valve.
Abnormal contents include equipment failure, clogging in the flow path, leakage, etc., and abnormal pressure and temperature can be judged by the control unit and monitored by the touch panel.
The pressure in the reaction tank (from the inlet valve to the outlet valve) is adjusted by the outlet valve 34 (back pressure valve) without going through the control unit.

Based on FIG. 2, the structure of the reaction tank 4 is demonstrated in detail.
The reaction tank 4 has an introduction port on one end side and a discharge port on the other end side, and heats and pressurizes the mixed fluid of the treatment target fluid and the oxidant to oxidize organic matter in the treatment target fluid by an oxidation reaction. It is for decomposing and processing the fluid to be processed.

The vertical reaction tank 4 includes a cylindrical reaction tank main body 42 that is integrally provided with an upper flange portion 40 and a lower flange portion 41.
An upper lid member 44 having an introduction port 43 for introducing a fluid into the reaction tank 4 is fixed to the upper flange portion 40, and a bottom lid member having a discharge port 45 for discharging a processed fluid to the lower flange portion 41. 46 is fixed.
The upper lid member 44 and the bottom lid member 46 may be integrated with the reaction tank main body 42, but in order to perform maintenance such as cleaning, it is better that either one has a detachable structure.
In the present embodiment, the upper lid member 44 is detachable.
The reaction tank 4 is provided with a space that maintains a high temperature and a high pressure to ensure a reaction time.

The introduction port 43 is inserted into the processing target fluid inflow pipe 47 for introducing the processing target fluid W into the reaction tank 4 and the processing target fluid inflow pipe 47 to introduce the air A into the reaction tank 4. It has a double pipe structure including a small-diameter oxidant inflow pipe 48.
The oxidant inflow pipe 48 has a longer entry length into the reaction tank 4 than the processing target fluid inflow pipe 47.
The processing target fluid W pumped by the raw water supply pump 10 flows into the reaction tank 4 through the processing target fluid inflow pipe 47, and moves in the reaction tank from the top to the bottom along the longitudinal direction thereof.
The air A pumped by the oxidant pump 15 flows into the reaction tank 4 through the oxidant inflow pipe 48 and is mixed with the processing target fluid W.
The mixed fluid that has moved downward in the reaction tank is in a state in which organic substances are almost completely oxidized and decomposed, and is discharged from the discharge port 45 as a processed mixed fluid.

Depending on the type of the processing target fluid W, hydrochloric acid derived from the chloro group of organic chloride or sulfuric acid derived from a sulfonyl group such as amino acid may be generated, and the inner wall of the reaction tank may be placed under strong acidity.
For this reason, as an example of the structure of the reaction vessel, a double structure including an outer cylinder excellent in pressure resistance and an inner cylinder excellent in corrosion resistance housed inside thereof can be shown.
An example of the inner cylinder is a cylinder made of titanium having excellent corrosion resistance.
The inner cylinder may be made of Ta, Au, Pt, Ir, Rh, or Pd instead of titanium.
The inner cylinder may be made of an alloy containing at least one of Ti, Ta, Au, Pt, Ir, Rh, and Pd.

On the other hand, the outer cylinder can be exemplified by a thick cylinder made of a metal material having excellent strength, such as stainless steel (SUS304, SUS316), Inconel 625, and the like.
If the thermal expansion coefficients of the outer cylinder and the inner cylinder are significantly different, a gap (not shown) is provided between the outer cylinder and the inner cylinder so that the pressure is equal to the inside of the inner cylinder. A structure called a pressure balance type that can be filled with water may be used.

A catalyst member 50 is disposed in the reaction tank 4 on the downstream side in the fluid movement direction.
In particular, when the purpose of treatment is complete decomposition of organic substances under superheated steam conditions, it is effective to provide a catalyst.
Even if organic matter that is not decomposed or ammonia nitrogen remains, oxidative decomposition can be promoted and it can be completely treated.
In FIG. 2, the code | symbol 56 has shown the sealing member.

The arrangement configuration and material of the catalyst member will be described below.
As shown in FIG. 3, the catalyst member 50 as a whole has a cylindrical shape along the inner diameter of the reaction tank 4.
Specifically, the catalyst member 50 has a configuration in which a plurality of catalyst members 50a, 50b, and 50c having the same shape and the same material are stacked in a fluid moving direction (vertical direction) without being fixed to each other.
That is, the upper catalyst member is simply placed and stacked on the catalyst member positioned below.
Each of the catalyst members 50a, 50b, and 50c is formed by joining a corrugated plate having a triangular bent point in a cylindrical shape.

As shown in FIG. 4, the catalyst member 50 a located at the lowermost position has a downstream end surface in the fluid movement direction placed on a convex portion (stepped portion) 54 provided on the inner peripheral surface of the reaction tank main body 42. Has been placed.
Specifically, on the upper surface of the convex portion 54, the bent portion 50a-1 that protrudes radially outward is placed and arranged.
Only the catalyst member 50 a is directly supported by the reaction vessel main body 42.

The outermost diameter of the catalyst member 50a is set to be slightly larger than the minimum diameter of the convex portion 54 from the normal temperature (when stopped) to the reaction temperature (during operation). Even if there is a diameter change due to, it has a structure that does not fall.
Further, the circumferential width of the convex portion 54 is set to such a length that another bent portion is placed even when the catalyst member 50a is displaced in the circumferential direction.
The convex part 54 is good also as a cyclic | annular protruding edge shape continued in the circumferential direction.

The catalyst member 50 is installed so as to be parallel to the fluid flow direction along the inner wall surface (inner circumferential surface) of the reaction tank, that is, to reduce the flow resistance.
The surface area of the catalyst member 50 formed of corrugated plates is larger than the corresponding surface area in the reaction vessel.
In other words, the surface area of the catalyst member 50 is larger than the area of the inner peripheral surface of the reaction tank that faces the catalyst member 50 at a radial position.
Thereby, catalyst performance (oxidative decomposition promotion performance) is improved.
Since the catalyst member 50 is formed of a corrugated plate in a cylindrical shape, the surface area of the catalyst member 50 compared to the case where a cylindrical catalyst member formed of a flat plate having a uniform thickness is arranged along the inner diameter of the reaction vessel, The cylindrical shape of the flat plate is larger than the surface area of the space occupied in the reaction vessel.

As a method of increasing the surface area, a method of forming fine irregularities on the surface is generally known. However, the catalyst member 50 according to the present embodiment increases the surface area by a bent shape (folded shape), and the surface is increased. It itself is a smooth surface with low resistance to fluid.
In the case of a surface having fine irregularities, there is a possibility that the inorganic substance adheres, but the possibility is extremely low on a smooth surface.
The catalyst member 50 is disposed along the inner diameter of the reaction tank, and there is a space for the inorganic material to fall and move inside.
In other words, a space in which inorganic substances do not adhere and accumulate is secured, and the decrease in catalyst performance due to this is complemented by the increase in surface area due to the corrugated plate shape of the catalyst member 50.

Each of the catalyst members 50a, 50b, and 50c covers a catalyst layer by immersing a base material in which corrugated plates are formed in a cylindrical shape in a plating bath.
As described above, since the catalyst member 50 has a three-part configuration, the vertical dimensions of the catalyst members 50a, 50b, and 50c are as small as one third of the integrated object.
For this reason, it has the merit on manufacture which can produce the catalyst member 50 also with a small plating bath.
In the present embodiment, the catalyst member 50 is divided into three stages, but the number of divisions is not limited to this.

As described above, the catalyst members 50a, 50b, and 50c are placed in a non-fixed state, so that during maintenance, they can be individually taken out and washed with water or ultrasonically. Easy to handle.
When the catalyst is deteriorated, in the configuration in which the catalyst is directly coated on the inner peripheral surface of the reaction tank, it is necessary to activate (recover the catalyst performance by cleaning) or replace the entire reaction tank, but in this embodiment, only the catalyst member 50 is used. It can be easily taken out.
Furthermore, in this embodiment, since the catalyst member 50 has a divided configuration, the catalyst member can be partially replaced.
That is, when the adhesion state of the inorganic substance is different in the entire catalyst member 50, it is possible to clean or replace only the portion where the adhesion amount is large during maintenance.

Due to the corrugated plate shape of the catalyst member 50, a space exists between the inner peripheral surface of the reaction tank 4 and the catalyst member 50.
For this reason, the reaction heat generated on the surface of the catalyst member 50 is less likely to move through the reaction vessel as compared with the configuration in which the catalyst is directly coated on the inner peripheral surface of the reaction vessel.
Thereby, the heat exchange downstream, that is, the heat exchange rate by the heat exchanger 22 is improved.
In the corrugated catalyst member 50, both the inner peripheral surface and the outer peripheral surface thereof have a shape in which the radial distance between the inner peripheral surface and the inner peripheral surface of the reaction tank changes in the circumferential direction.

The tip of each bent portion of the catalyst member 50 is the portion closest to the inner peripheral surface of the reaction tank and is not in contact with the inner peripheral surface.
Even if the position of the catalyst member is shifted and the tip of the bent portion comes into contact with the inner peripheral surface, line contact is made and the contact range becomes partial, so that the heat exchange rate is hardly lowered.
When the catalyst member is thermally expanded, strain is absorbed by the bent portion, and damage due to deformation of the catalyst member 50 is prevented.
That is, when the base material is to be deformed due to thermal expansion, the outward force can be dispersed in the lateral direction by the waveform.
For this reason, the unexpected situation that the catalyst member cannot be taken out due to thermal deformation at a high temperature in the reaction tank does not occur.

The space between the inner peripheral surface of the reaction tank 4 and the catalyst member 50 is also a space in which the mixed fluid moves (hereinafter referred to as “outer space”).
Since the catalyst member 50 is coated on the inner and outer surfaces with the catalyst layer, the processing target fluid W passing through the outer space is also catalyzed.

Each of the catalyst members 50a, 50b, and 50c is formed by covering a corrugated base material with a catalyst layer made of a catalyst material.
As the catalyst layer, at least the surface thereof is made of a catalyst substance that promotes oxidative decomposition of organic substances.
Examples of such a catalyst substance include Ru, Pd, Rh, Pt, Au, Ir, Os, Fe, Cu, Zn, Ni, Co, Ce, Ti, and Mn, or a compound containing at least one of them. Can be illustrated.
However, since the surface area is inevitably smaller than that of a conventional filling type or the like, it is preferable to select one having a high catalytic ability for the organic substance of the fluid to be treated.

Examples of the material of the base material include an alloy containing at least one of Fe, Ni, Cr, and Mo.
Furthermore, examples include Ti, Ta, Au, Pt, Ir, Rh, Pd, Zr, and V, alloys containing any one, ceramic, quartz glass, and the like.
From these, the necessary conditions, that is, cost and processability, ease of coating of the selected catalytic substance, mechanical strength, heat resistance under reaction conditions, and corrosion resistance may be selected.

In the present embodiment, the shape of the catalyst member 50 is a corrugated plate shape with a bent portion sharpened in a triangular shape, but is not limited thereto.
As shown in FIG. 5, a sine wave shape (FIG. 5A), a sawtooth wave shape (FIG. 5B), a rectangular wave shape (FIG. 5C), or a composite shape thereof may be used.
These shapes can be easily produced by pressing a flat metal plate without requiring welding.
The catalyst member 50 has a higher strength than a flat cylinder and can suppress deformation due to thermal expansion.
Moreover, in this embodiment, although the catalyst member 50 was formed with the corrugated sheet over the whole circumferential direction, it is good also considering at least one part in the circumferential direction as a corrugated sheet shape.

A second embodiment will be described with reference to FIG.
The same parts as those in the above-described embodiment are denoted by the same reference numerals, and the description of the configuration and functions described above will be omitted as appropriate, and only the main parts will be described.
In the above embodiment, the catalyst members 50a, 50b, and 50c are made of the same catalyst material and have the same shape.

In the reaction tank 4, the progress of the process varies depending on the position in the fluid moving direction. On the downstream side, the vaporization of the processing target fluid W proceeds compared to the upstream side.
In the gas phase state, gasification occurs and the mass transfer speed increases, so that the contact probability with respect to the catalyst member 50 located on the inner peripheral surface side away from the central portion of the reaction vessel increases.
That is, since the mass transfer rate of the organic substance in the treatment target fluid increases like a gas molecule, the probability that the organic substance contacts the catalyst layer of the catalyst member 50 is significantly improved.
From this point of view, as described above, the catalyst member 50 is disposed on the downstream side of the reaction tank 4.

In the present embodiment, in order to further improve the catalyst performance of the catalyst member 50, at least one of the catalyst members 50a, 50b, and 50c is made to have a different performance.
Each catalyst member 50c located on the most upstream side has a corrugated plate shape in which the number of bent portions 50c-1 is increased as shown in FIG.
As the number of the bent portions 50c-1 increases, the catalyst area increases and the catalyst performance improves.
You may coat | cover the catalyst substance with large catalyst performance, without changing a shape.
In this way, the oxidative decomposition reaction can be controlled by exchanging a part of the divided catalyst member 50.

In each said embodiment, although the catalyst member was made into the cylinder shape by a corrugated sheet, this invention is not limited to this.
For example, as shown in FIG. 7, it is good also as a structure which formed the groove | channel 58a extended in parallel with a fluid moving direction on the internal peripheral surface of the cylindrical-shaped catalyst member 58 (3rd Embodiment).
The groove 58a may be provided only on the outer peripheral surface, or may be provided on both the inner peripheral surface and the outer peripheral surface.

Next, an experiment confirming the superiority of the catalyst member having a corrugated shape (uneven shape) will be described.
[Example]
A prototype similar to the catalyst member 50 was made. That is, the wave shape is the triangular shape shown in FIG.
As a base material of the catalyst member, a material made of Ti was used. As the catalyst layer to be coated on the surface of the substrate, a catalyst layer made of Pd was used.
The maximum diameter of the cylinder was 13.9 mm, the cylinder height was 380 mm, the length m of one side of the wave (see FIG. 4) was 10 mm, and the wave angle θ (see FIG. 4) was 90 °.
The surface area of the catalyst member was 6080 cm ² on both sides.

The configuration of the fluid processing apparatus is the same as that shown in FIG.
The catalyst member was disposed in the reaction vessel 4. The operation was performed by setting the pressure in the reaction vessel 4 to 10 MPa and the temperature to 500 ° C.
In this fluid treatment apparatus, depending on the experimental conditions, the treatment target fluid W can be decomposed until the TOC concentration reaches several mg / L. However, in this experiment, the TOC concentration is several hundreds for comparison of the catalyst performance. Temperature conditions were set so as to be mg / L.
As the processing target fluid W, a mixed solution of methanol, silica, and alumina was used.
Its TOC concentration is 24375 mg / L.

Such a processing target fluid W was pumped into the reaction vessel at a flow rate of 20.0 kg / h.
At the same time, air was pumped into the reaction vessel at a flow rate of 12.4 kg / h.
The waste liquid of the treatment target fluid W was collected and its TOC concentration was measured, and it was 552 mg / L. Further, when the pressure upstream and downstream of the operating reaction tank was measured and the clogging of the catalyst was confirmed by the presence or absence of the differential pressure, the clogging of the catalyst was not observed.

[Comparative example]
As the catalyst member, a flat plate was used instead of a corrugated plate, and a cylindrical catalyst member having the same diameter and the same height was prototyped.
The surface area of the catalyst member was 4900 cm ² on both sides.
The cylindrical catalyst member 60 was placed in the reaction tank as shown in FIG. 8, and the operation was performed in the same manner as in the example. The TOC concentration of the drainage was measured and found to be 785 mg / L. No clogging of the catalyst was observed.

  A summary of the experimental results is shown in Table 1.

From the above experimental results, when processing a fluid to be processed using a reaction tank that is large enough to prevent the catalyst member from being blocked, that is, having a large diameter, the catalyst member having a cylindrical corrugated plate shape is more cylindrical. It was confirmed that the catalyst performance was increased as compared with the above case.
If easy cleaning is not considered, the flat cylindrical catalyst member 60 can be regarded as an alternative to the configuration in which the catalyst layer is directly coated on the inner peripheral surface of the reaction tank. It can be said that it has an advantage in comparison with.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to such specific embodiments, and unless specifically limited by the above description, the present invention described in the claims is not limited. Various modifications and changes are possible within the scope of the gist.
The effects described in the embodiments of the present invention are merely examples of the most preferable effects resulting from the present invention, and the effects of the present invention are limited to those described in the embodiments of the present invention. is not.

4 reaction tank 50 catalyst member 50a, 50b, 50c catalyst member 54 convex portion A air as oxidant W fluid to be treated

JP 2002-273194 A JP 2002-186843 A Japanese Patent No. 4838013 Japanese Patent No. 4986174

Claims (8)

A cylindrical reaction tank for treating the processing target fluid by decomposing an organic substance in the processing target fluid by an oxidation reaction under a heated and pressurized state of a mixed fluid of the processing target fluid and an oxidant,
Inside the reaction tank, a cylindrical catalyst member along the inner diameter of the reaction tank is disposed,
The fluid processing apparatus, wherein the catalyst member has a shape in which a surface area thereof is larger than a surface area in the reaction tank corresponding to the catalyst member. The fluid treatment apparatus according to claim 1,
The catalyst member is a fluid processing apparatus in which at least a part in a circumferential direction has a corrugated plate shape. The fluid processing apparatus according to claim 1 or 2,
The said catalyst member is a fluid processing apparatus with which the downstream end surface of a fluid moving direction is mounted in the convex part formed in the said reaction tank, and is fixed. In the fluid treatment apparatus according to any one of claims 1 to 3,
The fluid processing apparatus, wherein the catalyst member has a plurality of catalyst members stacked in a fluid moving direction to form a cylindrical shape as a whole. The fluid processing apparatus according to claim 4.
The fluid processing apparatus, wherein the plurality of catalyst members are not fixed to each other. In the fluid treatment apparatus according to claim 4 or 5,
A fluid processing apparatus, wherein a surface area of at least one of the plurality of catalyst members is different from that of the other catalyst members. In the fluid treatment apparatus according to claim 4 or 5,
A fluid processing apparatus in which at least one catalyst member of the plurality of catalyst members has a catalyst material or catalyst performance different from that of other catalyst members. In the fluid treatment apparatus according to any one of claims 1 to 7,
The fluid processing apparatus, wherein the catalyst member has a shape that forms a line contact when a portion closest to the inner peripheral surface of the reaction tank comes into contact with the inner peripheral surface of the reaction tank.

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