JP2001120986A - Batch type supercritical water reaction apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a batch type supercritical water reaction apparatus with which operation is easy. SOLUTION: This batch type supercritical water reaction apparatus 10 is an apparatus for treating hardly pulverizable organic solids by a supercritical water reaction and has first reactors 12A and 12B of a batch type which are connected in series, a second reactor 14 of a continuous type which is connected in series to the first reactor 12B, a water feeding means 16 which feeds supercritical water to the first reactor 12A, a air compressor 18 which feeds air as an oxidizing agent to the first and second reactors 12A and 12B, a reaction product outflow system 20 which subjects the reaction product fluid flowing out of the second reactor 14 to separation of gas from the liquid, and first and second temperature controllers 38A, 38B and 40 which control the temperature in the first and second reactors. The first reaction product fluid containing unrecompensed matter flowing out of the first reactor 12B is subjected to the supercritical water treatment in the second reactor 14, by which the perfect supercritical water treatment of the hardly pulverizable organic solids is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a batch type supercritical water reactor, and more particularly, to an operation which is easy and safe and in which an object to be treated is completely supercritical water so as not to generate undecomposed products. The present invention relates to a batch type supercritical water reactor capable of treating and operating with high thermal efficiency.

[0002]

2. Description of the Related Art With increasing awareness of environmental issues,
Attempts to decompose and detoxify environmental pollutants by utilizing supercritical water reaction, which has high ability to oxidize and decompose organic substances, have attracted attention. That is, harmful hardly decomposable organic substances, such as PCB (polychlorinated biphenyl), dioxin, and organic chlorinated compounds, which were difficult to decompose in the prior art by supercritical water reaction utilizing high reactivity of supercritical water. This is an attempt to decompose a solvent or the like and convert it into harmless products such as carbon dioxide, water, and inorganic salts. As one of the attempts, recently, supercritical water reaction has been applied to the treatment of various liquid and solid wastes such as sewage sludge, municipal waste, industrial wastewater, etc. containing such harmful organic compounds. The use of is being attempted.

[0003] A supercritical water reactor is a device that decomposes organic substances by using high reactivity of supercritical water. For example, harmful organic substances that are hardly decomposable are decomposed and harmless carbon dioxide and water are decomposed. In order to convert the hard-to-decompose high-molecular compounds into useful low-molecular compounds,
Its practical application is being actively studied. Supercritical water refers to water that is in a supercritical state, that is, water that is in a state beyond the critical point of water, and specifically, at a temperature of 374.1 ° C. or more and a pressure of 22.04 MPa or more. A state of water. Supercritical water has a high ability to dissolve organic substances and can completely dissolve non-polar substances, which are abundant in organic compounds, but has a very low ability to dissolve inorganic substances such as metals and salts. The supercritical water can be mixed with a gas such as oxygen or nitrogen at an arbitrary ratio to form a single phase.

Here, the basic configuration of a conventional supercritical water reactor will be described with reference to FIG. FIG. 4 is a flow sheet showing the configuration of a conventional supercritical water reactor. The conventional supercritical water reaction device 90 is a device for treating a fine solid water slurry such as sewage sludge by a supercritical water reaction, and as shown in FIG. A long pressure-resistant sealed reactor 91 having a tubular shape is provided. Further, the supercritical water reactor 90 has a preheater 92 for preheating the reaction fluid upstream of the reactor 91 and a heat exchanger for exchanging heat with the reaction fluid and cooling the reaction product fluid downstream of the reactor 91. An exchanger 93 and a cooler 94 for cooling the reaction product fluid with cooling water are provided.

Further, the supercritical water reactor 90 includes a cooler 9
A pressure gauge 96 for measuring the pressure in the reactor 91 and a pressure regulating valve 97 are provided in the reaction product line 95 downstream of the pressure gauge 4, and the pressure regulating valve 98 controls the pressure based on the measured value of the pressure gauge 96. The pressure in the reactor 91 is controlled by adjusting 97. Further, the supercritical water reactor 90 includes a gas-liquid separator 99 for gas-liquid separation of the reaction product fluid into gas and slurry downstream of the pressure control valve 97, and is further separated by the gas-liquid separator 99. Solid-liquid separator 1 for solid-liquid separation of a slurry-like reaction product to separate inorganic solids from the reaction product
00 is provided. The inorganic solid separated by the solid-liquid separator 100 is mainly an inorganic solid contained in the reaction product, but did not contribute to the reaction. May contain formed salts.

The preheater 92 includes an inner pipe through which a reactant composed of an organic substance containing an inorganic solid substance to be treated by the supercritical water reaction, for example, sewage sludge, and air as an oxidizing agent flows, and a heating medium for heating the reactant. It is configured as a double tube heat exchanger consisting of a flowing outer tube. The reactor 91 is a long tube-shaped reactor in order to secure the reaction time of the supercritical water reaction on the reactants, and supercritical water is retained in the entire area thereof to form a supercritical water region. are doing. The reaction fluid preheated to the reaction temperature enters the reactor 91 from the reactor inlet near the preheater 92, undergoes supercritical water reaction, and flows out of the reactor outlet as a reaction product fluid.

[0007] The heat exchanger 93 is a double tube heat exchanger comprising an inner tube through which the reaction product fluid flowing out of the reactor 91 flows, and an outer tube through which a heat medium heated by the reaction product fluid flows. The cooler 94 is a double-pipe heat exchanger composed of an inner pipe through which the reaction product fluid whose temperature has dropped through the heat exchanger 93 flows, and an outer pipe through which a cooling medium for cooling the reaction product fluid flows. ,It is configured. The outer tube of the heat exchanger 93 and the outer tube of the preheater 92 are connected to the heat medium so that the heat medium heated by the reaction product fluid in the heat exchanger 93 enters the preheater 92 and preheats the reactant fluid. They are connected by a pipe 101.

A liquid line to be treated 102 for feeding a reactant fluid, for example, sewage sludge, is connected to the inner pipe of the preheater 92, and an oxidizing agent for oxidizing organic substances, for example, air is fed to the liquid line for treatment 102. The air lines 103 are joined.
The sewage sludge is pressed into the liquid line 102 and the air line 103 by the sewage sludge pump 104 and the air by the air compressor 105, respectively. The reactant fluid composed of sewage sludge and air is preheated in a preheater 92 to the temperature at which the supercritical hydroxylation reaction starts, and then enters the reactor 91 and flows through the reactor 91 from the inlet to the outlet. The organic matter in the physical fluid is mainly converted into water, nitrogen, and carbon dioxide by the supercritical water reaction, and flows out of the reactor 91 as a reaction product. The length of the reactor 91 is determined so that the heating from the reaction start temperature to the reaction temperature is covered by the heat of oxidation of the organic matter in the sewage sludge, and thereafter, the time required for the complete decomposition reaction is provided. The reaction product fluid enters the inner tube of the heat exchanger 93, heats the heat medium, lowers its own temperature, then flows into the inner tube of the cooler 94, and is cooled by a coolant, for example, cooling water, and flows out. .

A reaction product line 95 is connected to an outlet of an inner tube of the cooler 94, and is connected to a gas-liquid separator 99 via a pressure control valve 97. In the gas-liquid separator 99, the reaction product is gas-liquid separated, and separated into a gaseous reaction product and a slurry-like reaction product. The gaseous reaction product is released to the atmosphere or goes to the next processing step, and the slurry-like reaction product is introduced into the solid-liquid separator 100. The reaction product in the form of a slurry is solid-liquid separated into a liquid processing liquid and an inorganic solid by the solid-liquid separator 100, and each is sent to the outside.

[0010]

The supercritical water reactor which has been put into practical use conventionally is, as described above, a continuous type reactor, and is practically used except for experimental devices such as bench scales. At present, a typical batch type supercritical water reactor has not been realized due to various technical problems. On the other hand, the objects to be treated with supercritical water have become various in proportion to the spread of environmental pollution in recent years, and contaminated solids and contaminated soil that cannot be treated by a continuous reaction device are required. Also need to be dealt with.

When solids are treated in a continuous reactor, it is necessary to grind the contaminated solids into a slurry, but some of the contaminated solids are technically difficult to grind. is there. Even if the contaminated solids could be slurried by grinding, there are the following problems inherent to the slurry. First, it is often difficult to stably feed a solid water slurry to a continuous reaction apparatus because the ground solids settle and separate or float and separate. Secondly, when the solid is treated, the inorganic matter contained in the solid does not participate in the supercritical water reaction as described above, and therefore, it is important that the solid is discharged together with the treatment liquid in order to continue the continuous operation. However, in a continuous reactor, inorganic substances,
Or it is not easy to discharge inorganic salts derived from inorganic substances. Third
However, there is a problem that a special device is required as a device for handling the slurry, and there is no commercially available product. Furthermore, the device for handling the slurry is severely damaged, and thus has a problem in economical efficiency due to a short life.

Therefore, it is necessary to charge the liquid to be treated or the substance to be treated into the reactor in a batch system, and to perform a batch-type supercritical water treatment. In addition, the batch reactor is easy to neutralize the liquid to be treated and suppress the corrosion of the reactor accompanying the supercritical water treatment of the liquid to be treated, and since the reaction vessel is opened for each batch, It has an excellent advantage that discharge of residual inorganic substances or inorganic salts is easy. In view of the above, an object of the present invention is to provide a practical batch type supercritical water reactor that is easy to operate.

[0013]

The inventor of the present invention has studied the technical problems that cannot be realized in a practical batch type supercritical water reactor, and as a result, the problems are summarized as follows. I found As a first problem, under supercritical water reaction conditions, for example, at a temperature of 600 ° C. and a pressure of 25 MPa, the density of the supercritical water is about 0.07 g / cm ³ , which is significantly smaller than that of ordinary water. Therefore, the object to be treated, water,
If the oxidizing agent and the auxiliary fuel are initially put into the reactor for processing, an extremely large-volume reaction vessel is required, which increases the equipment cost and raises the problem of economical efficiency of the apparatus.

Second, in the batch type supercritical water treatment for solids, if the amount of solids to be filled is too large,
Since the reaction temperature and reaction pressure of the reactor become too high,
There is a problem associated with the first problem that the amount of solids to be treated must be limited as compared with the capacity of the reactor.

[0015] The third problem is that it is difficult to accurately determine the quantitative balance between the object to be treated and the water to be charged into the reactor. As a result, as described below, it is difficult to control the reaction temperature. The oxidation reaction start temperature is set to TS,
The supercritical water oxidation reaction temperature is TR and the mass of the reactor is Wk
g, the mass of the processing object, water, and oxygen gas charged into the reactor are X kg, Y kg, and Z kg, respectively. Further, the average specific heat of the reactor components is calculated as Cpwkcal / kg.
° C, the average specific heat of the processing object, water, and oxygen gas charged into the reactor are Cpxkcal / kg ° C and Cpykca, respectively.
1 / kg ° C. and Cpzkcal / kg ° C., and the calorific value per unit mass of the object to be treated is Hkcal / kg. The total calorific value XH of the object to be processed has the following equation with the above-mentioned factor. Here, q is the amount of heat radiated from the reactor. XH = (Y · Cpy + X · Cpx + Z · Cpz + W · Cpw)
(TR-TS) + q

Therefore, if heat cannot be released so as to satisfy the above equation, the temperature inside the reactor rises,
There is a high risk of runaway reaction. In other words, it is difficult to control the temperature inside the reactor. Further, in order to increase the amount X of the solid matter to be treated using the same reactor, it is necessary to increase the heat release amount q. However, in a batch type supercritical water reactor, there is little means for externally controlling the progress of the reaction, and the temperature in the reactor is mainly dependent on the progress of the supercritical water reaction. Is extremely technically difficult.

Fourth, as the supercritical water reaction progresses, CO ₂ gas or N ₂ gas or the like is generated, and the pressure in the reactor increases, making it difficult to control the pressure.

Therefore, the inventor of the present invention has found that the first problem is that a semi-batch supercritical water reactor is provided, and the second problem is that a relatively large amount of solids is previously batch-processed in the first reactor. It has been decided to solve the problem by supercritical water treatment and then completely and completely supercritical water treatment of the reaction product fluid containing undecomposed substances flowing out of the first reactor in the second reactor. The third problem is that the temperature of the processing solution flowing out of the reactor is measured and the flow rate of the oxidizing agent is adjusted based on the temperature to control the temperature of the reactor. The point is that the generated CO ₂ gas, N ₂ gas, and the like are caused to flow out together with the processing liquid to solve the problems, and the present invention has been completed through repeated experiments.

In order to achieve the above object, based on the above findings, the batch type supercritical water reactor according to the present invention is openable and closable, accommodates the objects to be treated, and is sequentially connected in series. A plurality of first reactors for performing batch type supercritical water treatment, a water supply means for supplying supercritical water to a head reactor of the first reactor, and a tail end of the first reactor A continuous second reactor, into which a fluid containing undecomposed substances flowing out of the reactor is introduced, and further subjected to supercritical water treatment;
An oxidant feeding means for feeding an oxidant to each of the first and second reactors is provided.

According to the present invention, while the supercritical water and the oxidizing agent are fed by the water sending means and the oxidizing agent sending means, the object to be treated accommodated in the first reactor is subjected to the supercritical water treatment. Fluid containing the reaction product of the critical water reaction flows out of the first reactor. Since it is difficult to completely terminate the supercritical water reaction in the first reactor, the fluid flowing out of the first reactor tends to contain undecomposed substances. In the present invention, the undecomposed material refers to a substance that is further decomposed by performing supercritical water treatment to generate nitrogen, carbon dioxide, acid, water, and the like, and may be an environmentally harmful component. Many. Therefore, a second reactor connected in series to the last reactor of the first reactor is provided, and the fluid containing undecomposed substances flowing out of the first reactor is finally completely supercritical in the second reactor. Filling the first reactor with a relatively large amount of solids and completely performing the supercritical water treatment without making the reaction conditions of the supercritical water treatment in the first reactor severe by performing the water treatment Can be. Furthermore, since a plurality of first reactors are provided in series, there is an advantage that undecomposed products generated in the upstream first reactor are treated with supercritical water in the downstream first reactor. In the present invention, the system of the first reactors connected in series does not necessarily have to be one system, and for example, one or more second reactors may be provided in a plurality of first reactors. . In the model of the second reactor,
There is no limitation, and the reactor may be a tubular reactor, a vessel reactor, or a two-zone reactor.

Further, by introducing a fluid mainly containing supercritical water from the upstream first reactor to the downstream first reactor sequentially, the overall flow rate of supercritical water is reduced, The heat balance of the entire supercritical water reactor can be greatly improved.

In a preferred embodiment of the present invention, the second reactor is connected between at least two interconnected first reactors among the plurality of first reactors connected in series. And an oxidizing agent feeding means for feeding an oxidizing agent to the intermediate reactor, and superposing undecomposed substances in the fluid flowing out of the upstream first reactor in the intermediate reactor. The reaction product fluid that has undergone critical water treatment and exits the intermediate reactor is introduced into a first reactor downstream. By treating the fluid flowing out of the upstream first reactor with supercritical water in the intermediate reactor and then introducing the fluid flowing out of the intermediate reactor into the downstream first reactor, the fluid flowing out of the intermediate reactor is Since the supercritical water contains substantially no undecomposed products, the fluid flowing out of the upstream first reactor is not directly used as the supercritical water replenishment water of the downstream first reactor. In addition, the supercritical water reaction in the downstream first reactor can proceed even more effectively.

In a further preferred embodiment of the present invention, a first reactor outlet thermometer for measuring the temperature of the fluid flowing out of each of the first reactors and a temperature measured by the first reactor outlet thermometer are used. A first temperature control device for controlling the flow rate of the fluid flowing out of each of the first reactors to a target temperature by adjusting the flow rate of the oxidant fed into each of the first reactors. A second reactor outlet thermometer that measures the temperature of the fluid flowing out of each of the intermediate reactor and the second reactor;
On the basis of the temperature measured by the second reactor outlet thermometer, the flow rate of the oxidizing agent fed to each of the intermediate reactor and the second reactor is adjusted to adjust the flow rate of each of the intermediate reactor and the second reactor. And a second temperature control device for controlling the temperature of the fluid flowing out of the control unit to the target temperature.

In this embodiment, as described above, the first,
By controlling the temperature of the first, intermediate and second reactors by measuring the temperature of the reaction product fluid flowing out of the intermediate and second reactors and adjusting the flow rate of the oxidizing agent based on the temperatures. I have.

Preferably, a neutralizing and quenching means for feeding an aqueous alkali solution to the reaction product fluid flowing out of the second reactor and neutralizing and quenching the reaction product fluid is provided at an appropriate position. Thus, when the reaction product fluid is acidic, corrosion of the cooling unit, the gas-liquid separation unit, the liquid sending unit, and the like by the reaction product fluid can be prevented.

Practically, the batch type supercritical water reactor according to the present invention comprises a cooling means for cooling a reaction product fluid,
A gas-liquid separation unit for gas-liquid separation of the cooled reaction product fluid; and a liquid component obtained by gas-liquid separation by the gas-liquid separation unit, which is sent to a water supply unit to form at least a part of the supercritical water. Liquid means in place. Thus, a closed system can be configured for the liquid, so that environmental pollution due to drainage or the like does not occur. When the reaction product fluid is neutralized by the alkali agent, the liquid sending means includes an inorganic salt separating device for separating inorganic salts in the liquid component to be sent. Regarding the type of inorganic salt separation device, any type of ion exchange resin device can be suitably used, as long as it can separate the inorganic salt in the liquid component.

[0027]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Embodiment 1 This embodiment is an example of an embodiment of a batch type supercritical water reactor according to the present invention, and FIG. 1 is a view around a reactor of the batch type supercritical water reactor of this embodiment. FIG. 2 is a flow sheet showing the configuration, and FIG. 2 is a flow sheet of a reaction product outflow system of the batch type supercritical water reactor of the present embodiment.
The batch type supercritical water reactor 10 of the present embodiment (hereinafter, referred to as
The reaction device 10) is a device for treating organic solids that are difficult to pulverize in a batch manner by a supercritical water reaction. As shown in FIG. 1, the reaction apparatus 10 includes, as reactors, first reactors 12A and 12B and a first reactor 12B connected in series so as to perform batch-type supercritical water treatment. It has a continuous second reactor 14 that is connected in series, flows in a fluid containing undecomposed substances flowing out of the first reactor 12B, and further performs a supercritical water treatment. In addition, the reactor 10
As shown in FIG. 1 and FIG. 2, a water supply means 16 for supplying supercritical water to the first reactor 12A, a first reactor 12A,
B and an air compressor 18 for feeding air as an oxidant to the second reactor 14, and a reaction product outflow system 20 for cooling the reaction product fluid flowing out of the second reactor 14 and separating it into gas and liquid. ing.

The first reactors 12A and 12B are openable / closable autoclave-type reactors for accommodating an object to be treated and performing a supercritical water treatment, and support the object to be treated inside the reactor. A support plate 21 in the form of a mesh plate through which a reaction product and supercritical water pass, and an inner cylinder 22 which holds the object to be treated on the support plate 21 in one place so as not to be dispersed. The fluid that has flowed out of the first reactor 12A is introduced into the first reactor 12B via the first reactor outlet pipe 24A, and the first reactor 12B
, And the undecomposed matter in the fluid discharged from the first reactor 12A is subjected to the supercritical water treatment in the first reactor 12B. The second reactor 14 is the first reactor 1
This is a continuous reactor connected to the 2B first reactor outlet pipe 24B, and may be a tube type or a container type. The water supply means 16 includes a water tank 26 containing water and a water tank 2.
6 is provided with a water supply pump 28 for supplying the water contained in the reactor 6, and a heating furnace 30 for heating the water supplied by the water supply pump 28, and the supercritical water is supplied to the first reactor 12 through a water supply pipe 32.
Send water to A. Further, a CO concentration meter 66 for measuring the CO concentration in the gas component is provided in the first reactor outlet pipe 24B.

The air compressor 18 is a compressor of a type that can easily control the flow rate of air by adjusting a flow control valve provided on a discharge pipe. The air compressor 18 includes an air supply pipe 34A and a water supply pipe 32. To the first reactor 12A via the air supply pipe 34B and the first reactor outlet pipe 24A, and to the first reactor 12B via the air supply pipe 36B and the first reactor outlet pipe 2
4B, air is supplied to the second reactor 14 as an oxidizing agent. The incoming flow rate of the air compressor 18 is adjusted by the temperature control device based on the temperature of the reaction product fluid, as described below. That is, the reaction device 10
The first reactor 12A and the first reactor 12B control the temperature in the first reactor 12A and the first reactor 12B to control the temperature in the second reactor by controlling the amount of air to be fed into the second reactor 14, respectively. Temperature control devices 38A and 38B and a second temperature control device 40 are provided.

The first temperature control device 38A is connected to the first air supply pipe 34A on the discharge side of the air compressor 18 based on the temperature measured by the first thermometer 42A provided on the first reactor outlet pipe 24A. The opening degree of the provided first flow control valve 44A is adjusted to adjust the flow rate of the air to be supplied to the first reactor 12A, and the temperature inside the first reactor 12A is controlled to a predetermined temperature. That is,
When the temperature measurement value of the first thermometer 42A is higher than the predetermined temperature, the flow rate of air is reduced to suppress the progress of the supercritical water reaction in the first reactor 12A, and the temperature measurement value of the first thermometer 42A is reduced. When the temperature is lower than the predetermined temperature, the flow rate of air is increased to promote the progress of the supercritical water reaction. Usually, the first reactor 12
The target temperature of A is 500 to 550 ° C. The first temperature control device 38B is configured to control the air compressor 1 based on a temperature measurement value of a first thermometer 42B provided in the first reactor outlet pipe 24B.
8 to adjust the flow rate of the air to be fed into the first reactor 12B by adjusting the valve opening of the first flow control valve 44B provided in the first air supply pipe 34B on the discharge side. Is controlled to a predetermined temperature.

The second temperature control device 40 is connected to the second air supply pipe 36 on the discharge side of the air compressor 18 based on the temperature measured by the second thermometer 48 provided on the second reactor outlet pipe 46. The flow rate of the air fed into the second reactor 14 is adjusted by adjusting the valve opening of the second flow control valve 50 provided, and the second reactor 14
Is controlled to a predetermined temperature. That is, the second thermometer 48
Is higher than the predetermined temperature, the flow rate of air is reduced to suppress the progress of the supercritical water reaction, and the second thermometer 4
When the temperature measured in Step 8 is lower than the predetermined temperature, the flow rate of air is increased to complete the supercritical water reaction. Second reactor 1
The target temperature of No. 4 is about 600 to 650 ° C., and auxiliary fuel may be externally supplied as needed.

As shown in FIG. 2, the reaction product effluent system 20 is provided in a second reactor outlet pipe 46 for discharging a fluid from the second reactor 14, and the reaction product effluent flowing out of the second reactor 14. A cooler 52 for cooling the body, a gas-liquid separator 54 provided downstream of the cooler 52, and a pressure of the gas-liquid separator 54, and thus indirectly the second reactor 14 and further the first reactor 12A , B, and a liquid level control device 58 for controlling the liquid level of the gas-liquid separator 54.

The gas-liquid separator 54 separates the reaction product fluid flowing out of the second reactor 14 into a gas component and a water component by gas-liquid separation. The gas component is discharged to the atmosphere via a gas discharge pipe 60 connected to the top of the gas-liquid separator 54. The pressure control device 56 includes a pressure gauge 6 provided on the gas discharge pipe 60.
The valve opening of the pressure control valve 64 is adjusted based on the measurement value of 2, and the pressure of the gas-liquid separator 54 is controlled to be a predetermined pressure. Further, the gas discharge pipe 60 may be provided with a CO concentration meter 67 for measuring the concentration of CO gas in the gas component.

The liquid level control device 58 controls the liquid level of the gas-liquid separator 54 by adjusting the valve opening of a flow control valve 70 provided in a liquid outflow pipe 68 through which a water component flows out of the gas-liquid separator 54. Control. The reaction product effluent system 20 includes a booster pump 72 and an inorganic salt separator 74 in the liquid effluent pipes 68 upstream and downstream of the flow control valve 70, respectively. The water component therein is sent to the inorganic salt separator 74, where the inorganic salt is separated, and then sent to the water pipe 32 via the circulation pipe 76. The inorganic salt separation device 74 is a device that separates an inorganic salt in a liquid, and is, for example, an ion exchange resin device.

Further, as shown in FIG. 1, the reactor 10 is provided with a facility for injecting an alkaline aqueous solution into the outlet pipe 46 of the second reactor. The facility for injecting the alkaline aqueous solution includes an alkaline aqueous solution tank 78
And an alkaline aqueous solution injection pipe 82 connected to the second reactor outlet pipe 46. The alkaline aqueous solution pump 80 pumps an alkaline aqueous solution from an alkaline aqueous solution tank 78, and the second reactor Inject into outlet tube 46. By injecting the alkaline aqueous solution, the reaction product fluid can be neutralized and rapidly cooled. In particular, when the reaction product fluid flowing out of the second reactor 14 is acidic, it is preferable to inject an alkali aqueous solution to neutralize and rapidly cool.

Next, a method of operating the batch type supercritical water reactor 10 of the embodiment will be described with reference to FIGS. First, the first reactors 12A and 12B are opened, and the object to be treated for one batch operation is transferred to the support plate 21 in the inner cylinder 22.
On top, the first reactors 12A, B are closed. When the object to be treated is a slurry-like fluid, the first reactors 12A and 12B can be filled as it is via the water pipe 32 without opening the first reactors 12A and 12B. Next, the water pump 28
Is started, water is sent from the water tank 26 to the heating furnace 30 via the water pipe 32, heated, and supplied to the first reactor 12A. Water flowing out of the first reactor 12A is supplied to the first reactor 1A.
2B, the second reactor 14, and the gas-liquid separator 54 through the cooler 52. Next, the water extracted from the gas-liquid separator 54 is combined with the water from the water supply pump 28 by the booster pump 72 and the circulation pipe 76, heated in the heating furnace 30 and put into the reactor 12, and the circulation is gradually started. . As the amount of circulating water increases, the amount of water supplied by the water supply pump 28 is reduced, and finally, the amount of water flowing out of the system together with the gas from the gas discharge pipe 60 is supplemented by the water supply pump 28.

The temperature measured by the first thermometers 42A and 42B is 3
When the temperature reaches 70 ° C., the air compressor 18 is started,
Air is supplied to the first reactors 12A and 12B via the first air supply pipes 34A and 34B and the water supply pipe 32. In addition, air is also supplied from the first air supply pipe 36 to the second reactor 14. In order to keep the system pressure constant, the air compressor 18 may be operated from the start-up. Next, the first temperature control devices 38A and 38B are operated to
The valve openings of the first flow control valves 44A, B are adjusted so that the temperatures measured by the thermometers 42A, B become a predetermined temperature, and the amount of air sent to the first reactors 12A, B is adjusted. .

When the conditions in the first reactor 12 reach the conditions for the supercritical water reaction, the supercritical water reaction is started and proceeds gradually. Since undecomposed products remain in the reaction product fluid flowing out of the first reactor 12B, the reaction product fluid is further subjected to supercritical water treatment in the second reactor 14. The fluid flowing out of the second reactor outlet pipe 46 with the progress of the supercritical water reaction accompanies a gas component, for example, CO ₂ gas, and is cooled by the cooler 52 and then separated by the gas-liquid separator 54. The gas discharge pipe 60 is controlled under the control of the pressure control device 56.
Is released via

When the CO gas concentration is no longer detected in the CO gas concentration meter 66 provided in the first reactor outlet pipe 24B, it can be determined that the supercritical water reaction in the first reactors 12A and 12B has reached the end point. . Alternatively, a reaction test can be separately performed in advance using a small basic tester, and the reaction termination time can be predicted from the result. In addition, it is preferable to confirm that there is no CO gas in the released gas from the CO concentration 67 provided in the gas release pipe 60. When the supercritical water reaction reaches the end point, the batch type supercritical water reactor 10
The overall pressure is reduced, then the first reactor 12 is opened.

Embodiment 2 This embodiment is another embodiment of the batch type supercritical water reactor according to the present invention, and FIG. 3 is a batch type supercritical water reactor of this embodiment. 2 is a flow sheet showing the configuration of FIG. Batch type supercritical water reactor 86 of this embodiment
The reaction device 86 (hereinafter, referred to as a reaction device 86) is a device that batch-processes an organic solid that is difficult to pulverize by a supercritical water reaction, as in the first embodiment. As shown in FIG. 3, the reactor 86 has a configuration in which the second reactor 14A is provided between the first reactor 12A and the first reactor 12B in addition to the configuration of the reactor 10 of the first embodiment. The second reactor 14A includes a temperature controller 40A having the same configuration as the temperature controller 40 of the second reactor 14 of the first embodiment. In FIG. 3,
The components related to the second reactor 14 of the first embodiment are denoted by a suffix B for distinction.

[0041]

According to the present invention, by providing a batch-type reactor for performing supercritical water treatment and a continuous-type reactor downstream of the batch-type reactor, an object to be treated is pretreated by the batch-type reactor. It is possible to carry out a supercritical water treatment as a treatment and then to carry out a supercritical water treatment completely by a continuous reactor so that no undecomposed products remain. In addition, by sequentially introducing a fluid mainly containing supercritical water from the upstream first reactor to the downstream first reactor, the overall inflow rate of the supercritical water is reduced, and the supercritical water is reduced. The heat balance of the entire reactor can be greatly improved. Further, based on the temperature measurement value of the fluid flowing out of the first reactor, the flow rate of the oxidizing agent to the first reactor is adjusted by the temperature control device so that the temperature of the fluid becomes the target temperature. By controlling the temperature in the first reactor, an easy and safe batch type supercritical water reactor is realized.

[Brief description of the drawings]

FIG. 1 is a flow sheet showing a configuration around a reactor of a batch type supercritical water reactor of Embodiment 1.

FIG. 2 is a flow sheet showing a configuration of a reaction product fluid outflow system of the batch type supercritical water reactor of Embodiment 1.

FIG. 3 is a flow sheet showing a configuration around a reactor of a batch type supercritical water reactor of Embodiment 2.

FIG. 4 is a flow sheet showing a configuration of a conventional supercritical water reactor.

[Explanation of symbols]

 Reference Signs List 10 Batch type supercritical water reactor of Embodiment 1 12A, B First reactor 14, 14A, B Second reactor 16 Water supply means 18 Air compressor 20 Reaction product outflow system 22 Plate-shaped support plate 24A , B first reactor outlet pipe 26 water tank 28 water pump 30 heating furnace 32 water pipe 34A, B first air supply pipe 36A, B second air supply pipe 38A, B first temperature control device 40A, B second temperature Controllers 42A, B First thermometer 44A, B First flow control valve 46A, B Second reactor outlet pipe 48A, B Second thermometer 50 Second flow control valve 52 Cooler 54 Gas-liquid separator 56 Pressure control Device 58 Liquid level control device 60 Gas discharge pipe 62 Pressure gauge 64 Pressure control valve 66, 67 CO concentration meter 68 Liquid outflow pipe 70 Flow control valve 72 Booster pump 74 Inorganic salt separation device 76 Circulation Tube 78 Alkaline aqueous solution tank 80 Alkaline aqueous solution pump 82 Alkaline aqueous solution injection tube 86 Supercritical water reactor of Embodiment 2 90 Conventional continuous supercritical water reactor 91 Pressure-resistant closed reactor 92 Preheater 93 Heat exchanger 94 Cooling Apparatus 95 Reaction product line 96 Pressure gauge 97 Pressure control valve 98 Pressure controller 99 Gas-liquid separator 100 Solid-liquid separator 101 Heat medium pipe 102 Liquid line to be treated 103 Air line 104 Sewage sludge pump 105 Air compressor

Continued on the front page F-term (reference) 4D004 AA02 AB06 AB07 AC04 CA22 CA36 CA39 CB04 CB31 CC02 DA02 DA06 4D050 AA13 AA15 AB19 BB01 BC01 BC02 BD02 BD06 BD08 CA01 CA08 CA13 CA20 4D059 AA03 BC01 DA01 DA47 EA08 EA20 AEB A37 AEB EB20 BA06 BD15 CA02 CA65 CA66 DA01 EB01

Claims (6)

[Claims] 1. A plurality of first reactors, each of which is openable and closable, accommodates an object to be treated, is sequentially connected in series, and performs batch type supercritical water treatment; A water supply means for supplying supercritical water to the head reactor of one reactor, a fluid containing undecomposed substances flowing out of the tail reactor of the first reactor, and further performing supercritical water treatment; A batch type supercritical water reactor, comprising: a second reactor of a type; and an oxidizing agent feeding means for feeding an oxidizing agent to each of the first reactor and the second reactor. 2. An intermediate reactor having the same configuration as the second reactor, between at least two interconnected first reactors among a plurality of first reactors connected in series. And an oxidizing agent feeding means feeds the oxidizing agent into the intermediate reactor, treats undecomposed substances in the fluid flowing out of the upstream first reactor with supercritical water in the intermediate reactor, and performs the intermediate reaction. The batch type supercritical water reactor according to claim 1, wherein the reaction product fluid flowing out of the reactor is introduced into a first reactor downstream. 3. A first reactor outlet thermometer for measuring a temperature of a fluid flowing out of each of the first reactors, and each of the first reactors based on a temperature measured by the first reactor outlet thermometer. A first temperature control device for controlling a flow rate of a fluid flowing out of each of the first reactors to a target temperature by adjusting a flow rate of the oxidizing agent fed to the first reactor, an intermediate reactor, and a second temperature controller. A second reactor outlet thermometer for measuring the temperature of the fluid flowing out of each of the reactors, and a thermometer for each of the intermediate reactor and the second reactor based on the temperature measured by the second reactor outlet thermometer. And a second temperature control device that controls the flow rate of the oxidizing agent to be supplied so as to control the temperature of the fluid flowing out of each of the intermediate reactor and the second reactor to the target temperature. The batch type supercritical water reactor according to claim 1 or 2, wherein 4. A neutralizing and quenching means for feeding an aqueous alkaline solution to the reaction product fluid flowing out of the second reactor to neutralize and quench the reaction product fluid. 3. A batch-type supercritical water reactor as set forth in claim 2, wherein the device is provided downstream of the second thermometer. 5. A cooling means for cooling a reaction product fluid, a gas-liquid separation means for gas-liquid separation of the cooled reaction product fluid, and a water supply means for supplying a liquid component obtained by gas-liquid separation by the gas-liquid separation means. And a liquid sending means for sending at least a part of the supercritical water downstream of the second reactor in claim 1 or 2, and an outlet of the second reactor in claim 3 5. A batch-type supercritical water reactor, comprising: a downstream of the thermometer of claim 4; 6. The batch type supercritical water reactor according to claim 5, wherein the liquid sending means includes an inorganic salt separating device for separating inorganic salts in a liquid component to be sent.