JP2001120987A - 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 a first reactor 12 of a batch type, a second reactor 14 of a continuous vessel type of a two-zone system which is connected in series to the first reactor, a water feeding means 16 which feeds supercritical water to the first reactor 12, an air compressor 18 which feeds air as an oxidizing agent to the firs and second reactors, a reaction product outflow system 20 which subjects the reaction product fluid and subcritical water drain flowing out of the second reactor 14 to separation of gas from the liquid, a subcriticl water drain outflow system 21, and a firs and a second temperature controllers 38 and 40 which control the temperatures in the first and second reactors. The first reaction product fluid containing unrecompensed matter flowing out of the first reactor 12 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. The suppression of the corrosiveness of the second reactor 14 by the two-zone system 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 a supercritical water reactor which is easy and safe to operate, and which completely removes an object to be treated so as not to generate undecomposed substances. The present invention relates to a batch type supercritical water reactor in which water is treated and neutralization of an acid generated by the supercritical water reaction is performed to suppress corrosion of the device.

[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 solids separated by the solid-liquid separator 100 are mainly inorganic solids contained in the reaction product, but have not contributed to the reaction. May also contain salt.

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.

[0012] Therefore, it is necessary to put the object to be treated into the reactor in a batch system and perform a batch-type supercritical water treatment. Further, the batch-type reactor has an excellent advantage that the reaction container is opened for each batch, so that residual inorganic substances or inorganic salts can be easily discharged. 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, a batch type supercritical water reactor according to the present invention is openable and closable, accommodates an object to be treated, and performs batch type supercritical water treatment. A first reactor for applying supercritical water to the first reactor, a first oxidant feeding means for feeding an oxidizing agent to the first reactor, and a subcritical water area in a lower portion, A continuous Vessel type reactor having a supercritical water area at an upper part thereof, wherein a first reaction product fluid containing undecomposed substances flowing out of the first reactor flows into the supercritical water area; A second reactor for subjecting the second reaction product fluid to flow out of the supercritical water area by performing a critical water treatment, flowing water into the subcritical water area, and discharging subcritical water drainage from the subcritical water area; A second oxidizing agent feeding means for feeding an oxidizing agent to the reactor;
And an alkali injection means for injecting an alkali agent into the reactor.

In the present invention, the result of performing the supercritical water treatment on the object to be treated accommodated in the first reactor while feeding the supercritical water and the oxidant by the water supply means and the first oxidant supply means. A first reaction product fluid containing a reaction product of the supercritical water reaction flows out of the first reactor. Since it is difficult to completely terminate the supercritical water reaction in the first reactor, the first reaction product fluid flowing out of the first reactor is inevitably
It is easy to include undecomposed products. In the present invention, the undecomposed material is
A substance that is further decomposed by performing supercritical water treatment to produce nitrogen, carbon dioxide, acid, water, and the like, and is often an environmentally harmful component. Therefore, in the present invention, a two-zone type second reactor having a subcritical water area in the lower part and a supercritical water area in the upper part is provided in series with the first reactor. Then, the first reaction product fluid containing the undecomposed matter flowing out of the first reactor is introduced into the supercritical water area of the second reactor, and finally the second reactor is completely treated with supercritical water. The supercritical water treatment can be completely performed by filling the first reactor with a relatively large amount of solids without making the reaction conditions for the supercritical water treatment in the first reactor severe. Further, in the present invention, since the second reactor is a two-zone reactor, when the first reaction product fluid is acidic, it is injected with an alkali agent to neutralize the fluid, which is generated by the neutralization reaction.
Salts insoluble in supercritical water can be collected in a subcritical water area, dissolved in subcritical water drainage, and discharged. Since the acidity of the first reaction product fluid can be neutralized, corrosion of downstream equipment including the second reactor can be suppressed, and the second reactor and the like can be made of an economical material having relatively low corrosion resistance. . In the present invention, the number of the first and second reactors is not necessarily one.
There is no need to provide a plurality of first
It is also possible to provide one or more second reactors after the reactor.

In a preferred embodiment of the present invention, the first thermometer for measuring the temperature of the first reaction product fluid, and the oxidizing of the first oxidant feeding means based on the temperature measured by the first thermometer. A first temperature control device for controlling the flow rate of the agent so as to control the temperature of the first reaction product fluid to the target temperature, and the temperature of the second reaction product fluid flowing out of the second reactor. Based on the second thermometer to be measured and the temperature measured by the second thermometer, the flow rate of the oxidant supplied to the second oxidant supply means is adjusted so that the temperature of the second reaction product fluid becomes the target temperature. And a second temperature control device for controlling the temperature to

In this embodiment, as described above, the temperature of the reaction product fluid flowing out of the first and second reactors is measured, and the flow rate of the oxidizing agent is adjusted based on the measured temperatures. And controlling the temperature of the second reactor.

Preferably, means for returning a part of the second reaction product fluid to the first reactor, cooling the remainder of the first reaction product fluid, gas-liquid separation, and heating and raising the obtained water Means for feeding water as a part of supercritical water to the first reactor. Since the second reaction product fluid is mainly composed of supercritical water, a part or a substantial part of the second reaction product fluid is returned to the first reactor to temporarily convert the first reaction product fluid. The heat balance can be greatly improved as compared with a method in which water obtained by cooling and gas-liquid separation is heated under pressure and converted into supercritical water. Then, the remaining part is cooled and gas-liquid separated to remove gas components generated from the processing object and nitrogen components in the supplied air.

[0024]

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 flow chart showing a configuration of a batch type supercritical water reactor of this embodiment. FIG. 2 is a flow sheet showing the configuration of the second reaction product fluid outflow system and the subcritical water drainage outflow system of the batch type supercritical water reactor of this embodiment. The batch type supercritical water reactor 10 (hereinafter, referred to as the reactor 10) of the present embodiment includes:
This is an apparatus that batch-processes organic solids that are difficult to pulverize by a supercritical water reaction. As shown in FIG. 1, the reactor 10 includes a first reactor 12 for performing batch type supercritical water treatment.
And the first containing the undecomposed material that has flowed out of the first reactor 12.
A continuous vessel-type second reactor 14 connected in series to the first reactor 12 is provided for inflowing the reaction product fluid and further performing supercritical water treatment. Further, as shown in FIGS. 1 and 2, the reactor 10 includes a water supply means 16 for supplying supercritical water to the first reactor 12, and an oxidizing agent for the first reactor 12 and the second reactor 14. An air compressor 18 for introducing air, a reaction product effluent system 20 for cooling and gas-liquid separation of a second reaction product fluid and subcritical water drainage flowing out of the second reactor 14, and a subcritical water, respectively. Drainage system 21
And

The first reactor 12 is an openable / closable autoclave-type reactor that accommodates an object to be treated and performs a supercritical water treatment. The first reactor 12 supports the object to be treated inside the reactor and generates the object. It has an eyelet-shaped support plate 21 through which reactants and supercritical water pass, and an inner cylinder 22 that holds the object to be treated on the support plate 21 in one place so as not to be dispersed. Second reactor 14
Is a two-zone continuous Vessel reactor having a supercritical water area 24 in the upper part and a subcritical water area 25 in the lower part, and is connected to the first reactor outlet pipe 23 of the first reactor 12, The first reaction product fluid is introduced into the supercritical water zone 24. The second reactor 14 allows the second reaction product fluid to flow out of the supercritical water area 24 via the second reactor outlet pipe 46 and the subcritical water from the subcritical water area 25 via the subcritical water drain pipe 47. Drain water drainage. Also, the first reactor outlet pipe 23
Is provided with a CO concentration meter 66 for measuring the CO concentration in the gas component.

The water supply means 16 includes a water tank 2 containing water.
6, a water supply pump 28 for supplying water contained in the water tank 26, and a heating furnace 30 for heating the water supplied by the water supply pump 28, and the supercritical water is supplied through a first water supply pipe 32. 1 Water is supplied to the reactor 12. In addition, water supply means 16
Supplies water to the subcritical water area 25 of the second reactor 14 by the water pump 28 through the second water pipe 33.

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 in the discharge pipe.
And the water supply pipe 32 to the first reactor 12 and the second
The second through the air supply pipe 36 and the first reactor outlet pipe 23
Each of the reactors 14 is fed with air 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 apparatus 10 includes the first reactor 12
And a first temperature control device 38 and a second temperature control for controlling the temperature in the first reactor 12 and the temperature in the second reactor, respectively, by adjusting the amount of air sent into the second reactor 14. An apparatus 40 is provided.

The first temperature control device 38 is provided in the first air supply pipe 34 on the discharge side of the air compressor 18 based on the temperature measured by the first thermometer 42 provided in the first reactor outlet pipe 23. The opening degree of the first flow control valve 44 is adjusted to adjust the flow rate of the air fed into the first reactor 12, and the temperature inside the first reactor 12 is controlled to a predetermined temperature. That is, when the temperature measurement value of the first thermometer 42 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 12, and the temperature measurement of the first thermometer 42 is performed. When the value is lower than the predetermined temperature, the flow rate of air is increased to promote the progress of the supercritical water reaction. Usually, the target temperature of the first reactor is 500-550.
It is about ° C.

The second temperature control device 40 is provided in 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 in 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 to control the temperature inside the second reactor 14 to a predetermined temperature. That is, when the temperature measured by 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 48
When the measured temperature is lower than the predetermined temperature, the flow rate of air is increased to complete the supercritical water reaction. Second reactor 14
Has a target temperature of about 600 to 650 ° C., and an auxiliary fuel may be supplied from the outside if necessary.

As shown in FIG. 2, the reaction product effluent system 20 is provided with a second product 14 flowing out of the supercritical water area 24 of the second reactor 14.
A first cooler 52 provided in the second reactor outlet pipe 46 for discharging the reaction product fluid and cooling the second reaction product fluid
A first gas-liquid separator 54 provided downstream of the first cooler 52, and a pressure of the first gas-liquid separator 54, and thus indirectly the second reactor 14 and further the first reactor 12 A pressure controller 56 for controlling the pressure and a first liquid level controller 58 for controlling the liquid level of the gas-liquid separator 54 are provided.

The first gas-liquid separator 54 separates the second 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 supplied to the first gas-liquid separator 5
4 is discharged to the atmosphere via a gas discharge tube 60 connected to the top. The pressure control device 56 adjusts the opening degree of the pressure control valve 64 based on the measurement value of the pressure gauge 62 provided in the gas discharge pipe 60 so that the pressure of the first gas-liquid separator 54 becomes a predetermined pressure. To control. The gas discharge pipe 60 has a CO concentration meter 6 for measuring the concentration of CO gas in the gas component.
7 may be provided. The first liquid level control device 58 adjusts the liquid level of the gas-liquid separator 54 by adjusting the valve opening of the flow control valve 70 provided in the liquid outflow pipe 68 through which the water component flows out from the gas-liquid separator 54. Control. Part of the water component flowing out of the liquid outflow pipe 68 is returned to the water tank 26, and the remainder is sent out of the system.

As shown in FIG. 2, the subcritical water drainage outflow system 21 is provided in a subcritical water drain pipe 47 for discharging subcritical water drainage from the subcritical water area 25 of the second reactor 14, A second cooler 53 for cooling the waste water, and a second gas-liquid separator 55 provided downstream of the second cooler 53 and pressure-controlled together with the first gas-liquid separator 54 by a pressure controller 56.
And a second liquid level control device 59 for controlling the liquid level of the second gas-liquid separator 55, and an inorganic salt separation device 61 for removing salts in the gas-liquid separated liquid.

The second gas-liquid separator 55 separates subcritical water discharged from the subcritical water area 25 of the second reactor 14 into a gas component and a water component by gas-liquid separation. The gas component is discharged from the top of the second gas-liquid separator 55 to the atmosphere via the second gas discharge pipe 63 connected to the gas discharge pipe 60. The second liquid level control device 59 is provided with a flow control valve 71 provided in a subcritical water drainage outflow pipe 69 through which a water component flows out from the second gas-liquid separator 55.
The liquid level of the second gas-liquid separator 55 is controlled by adjusting the opening degree of the valve. The subcritical water drainage flowing out of the second gas-liquid separator 55 through the subcritical water drainage outflow pipe 69 is subjected to inorganic salt separation processing through the inorganic salt separation device 61, and then sent to the outside of the system. However, when the concentration of the inorganic salt in the subcritical water drainage is low, it is not always necessary to perform the inorganic salt separation treatment.
The inorganic salt separation device 61 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 first reactor outlet pipe 23. The facility for injecting the alkaline aqueous solution includes an alkaline aqueous solution tank 72 and an alkaline aqueous solution pump 74.
And an alkaline aqueous solution injection pipe 76 connected to the first reactor outlet pipe 23. The alkaline aqueous solution pump 74 pumps the alkaline aqueous solution from the alkaline aqueous solution tank 72 to the first reactor through the alkaline aqueous solution injection pipe 76. Inject into outlet tube 23.

Next, a method of operating the batch type supercritical water reactor 10 of the embodiment will be described with reference to FIG. First, the first reactor 12 is opened, an object to be treated for one batch operation is placed on the support plate 21 in the inner cylinder 22, and the first reactor 12 is closed. When the object to be treated is a slurry-like fluid, the first reactor 12 can be filled through the water pipe 32 or the like without opening the first reactor 12. Next, the water pump 28 is started to activate the water tank 26.
Is supplied to the heating furnace 30 through the water supply pipe 32, heated and supplied to the first reactor 12. Water flowing out of the first reactor 12 enters the first gas-liquid separator 54 through the second reactor 14 and the first cooler 52. Next, the first gas-liquid separator 5
4 from the liquid outflow pipe 68 to the water tank 2
6 by a circulating means (not shown) for returning to the water supply pump 2
8 and heated in a heating furnace 30 to form a reactor 1
2 and slowly start circulation. As the amount of water in the circulation increases, the amount of water supplied by the water pump 28 is reduced,
Eventually, the amount of water flowing out of the system together with the gas from the gas discharge pipe 60 is replenished by the water supply pump 28. Next, the second reactor 14 is placed in the subcritical water area 25 of the second reactor 14.
Water is introduced from the water supply pipe 33 and discharged from the subcritical water drain pipe 47.

The temperature measured by the first thermometer 42 is 370 ° C.
When the air compressor 18 is reached, the air compressor 18 is started, and air is supplied to the first reactor 12 via the first air supply pipe 34 and the water supply pipe 32 to the second air supply pipe 36 and the first reactor outlet. Air is fed into the second reactor 14 via the pipes 23, respectively. In order to keep the system pressure constant, the air compressor 18 may be operated from the start-up. In addition, both the first reactor and the second reactor can be heated to a predetermined temperature by a heating means such as an electric furnace set outside. In this case, in addition to an electric furnace, heating medium heating or the like can be used as the external heating means. Next, the first temperature control device 38 is operated to adjust the valve opening of the first flow rate control valve 44 so that the temperature measured by the first thermometer 42 becomes a predetermined temperature. Adjust the amount of air sent to

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 substances remain in the first reaction product fluid flowing out of the first reactor 12, supercritical water treatment is further performed on the first reaction product fluid in the second reactor.
The fluid flowing out of the second reactor outlet pipe 46 with the progress of the supercritical water reaction is accompanied by a gas component, for example, CO ₂ gas, and after being cooled by the first cooler 52, the first gas-liquid separation is performed. And separated under the control of a pressure controller 56,
The gas is discharged through the gas discharge tube 60.

The undecomposed matter in the first reaction product fluid is completely treated with supercritical water, so that the CO gas concentration in the second reactor 14 is maintained at a constant low value by the CO gas concentration meter. Adjust the temperature of the. When the CO gas concentration provided in the first reactor outlet pipe 23 is no longer detected, it can be determined that the supercritical water reaction in the first reactor 12 has reached the end point. Or,
Separately, a reaction test can be 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 by a CO concentration meter 67 provided in the gas discharge pipe 60.
When the supercritical water reaction reaches the end point, the pressure of the entire batch type supercritical water reactor 10 is reduced, and then the first reactor 1
Release 2

Embodiment 2 This embodiment is another embodiment of the batch type supercritical water reactor according to the present invention. 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 80 of this embodiment
The reaction device 80 (hereinafter, referred to as a reaction device 80) is a device that batch-processes hard-to-pulverize organic solids by a supercritical water reaction, similarly to the first embodiment. As shown in FIG. 3, the reactor 80 includes a booster pump 82 in the second reactor outlet pipe 46 and the second reactor 14 flowing out of the supercritical water area 24 of the second reactor 14.
It has the same configuration as that of the first embodiment except that a part of the reaction product fluid is returned to the first reactor 12 via the return pipe 84.

The operation of the reactor 80 of this embodiment is the same as that of the reactor 10 of embodiment 1 except that a part of the second reaction product fluid is returned to the first reactor 12 by the booster pump 32. The same is true. Thereby, since the flow rate of the supercritical water sent to the first reactor 12 by the water feeding means 16 can be reduced, the amount of heating by the heater 30 is reduced, and the heat balance can be greatly improved.

[0041]

According to the present invention, by providing a batch type reactor for performing supercritical water treatment and a two-zone type continuous type reactor downstream of the batch type reactor, the processing target can be batch type. Supercritical water treatment can be carried out in a pretreatment manner by a reactor, and then, supercritical water treatment can be carried out completely by a continuous reactor so that no undecomposed products remain. Further, based on the temperature measurement value of the first reaction product fluid, the flow rate of the oxidant supplied to the first reactor is adjusted by the temperature control device, so that the first temperature of the fluid becomes the target temperature. By controlling the temperature inside the reactor, an easy and safe batch type supercritical water reactor is realized. Further, in the present invention, since the second reactor is a two-zone reactor, when the first reaction product fluid is acidic, it is injected with an alkali agent to neutralize the fluid, which is generated by the neutralization reaction. Salts insoluble in supercritical water can be collected in a subcritical water area, dissolved in subcritical water drainage, and discharged. Since the acidity of the first reaction product fluid can be neutralized, the corrosiveness of the second reactor can be suppressed, and the downstream equipment including the second reactor can be made of an economical material having relatively low corrosion resistance. .

[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 second reaction product fluid outflow system and a subcritical water drainage 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 12 First reactor 14 Second reactor 16 Water supply means 18 Air compressor 20 Reaction product outflow system 22 Plate-shaped support plate 23 First reactor outlet pipe 24 Supercritical water area 25 Subcritical water area 26 Water tank 28 Water pump 30 Heating furnace 32 First water pipe 33 Second water pipe 34 First air supply pipe 36 Second air supply pipe 38 First temperature control device 40 Second temperature control Apparatus 42 First thermometer 44 First flow control valve 46 Second reactor outlet pipe 47 Subcritical water drain pipe 48 Second thermometer 50 Second flow control valve 52 First cooler 53 Second cooler 54 First gas Liquid separator 55 Second gas-liquid separator 56 Pressure controller 58 First liquid level controller 59 Second liquid level controller 60 Gas release pipe 61 Inorganic salt separator 62 Pressure gauge 63 Second gas release pipe 64 Pressure regulation Valves 66, 67 CO concentration meter 68 Liquid outflow pipe 69 Subcritical water drainage outflow pipe 70 Flow control valve 72 Alkaline aqueous solution tank 74 Alkaline aqueous solution pump 76 Alkaline aqueous solution injection pipe 80 Batch type supercritical water reactor 82 of Embodiment 2 82 Booster・ Pump 84 Return pipe 90 Conventional continuous supercritical water reactor 91 Pressure tight sealed reactor 92 Preheater 93 Heat exchanger 94 Cooler 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

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 4D004 AA02 AB06 AB07 AC04 CA22 CA36 CA39 CB04 CC02 DA01 DA02 DA06 4D050 AA13 AA15 AB19 BB01 BC01 BC02 BC10 BD02 BD06 BD08 CA01 CA08 CA13 4D059 AA03 BC01 DA01 DA47 EA08 EB20 EB08 EB20 EB08 EB20 EB08 AA15 AA35 AA37 BA05 BA06 BD13 CA02 CA65 CA66 DA01 DA11 EA06 EB01

Claims (3)

[Claims] 1. A first reactor which is openable and closable, accommodates an object to be treated, and performs batch type supercritical water treatment, a water supply means for supplying supercritical water to the first reactor, A first oxidant feeding means for feeding an oxidant to the reactor, a subcritical water area at a lower part, and a supercritical water area at an upper part,
A continuous reaction vessel fluid having a non-decomposed product and flowing out of the first reactor into the supercritical water area, and further performing a supercritical water treatment to obtain a supercritical water area. A second reactor for causing a second reaction product fluid to flow out of the sub-critical water area and flowing out sub-critical water drainage from the sub-critical water area, and feeding an oxidant to the second reactor A batch type supercritical water reactor, comprising: a second oxidizing agent feeding unit; and an alkali injecting unit for injecting an alkali agent into the second reactor. 2. A first thermometer for measuring the temperature of the first reaction product fluid, and a flow rate of the oxidant supplied by the first oxidant supply means is adjusted based on a temperature measured by the first thermometer. A first temperature control device that controls the temperature of the first reaction product fluid to a target temperature; and a second thermometer that measures the temperature of the second reaction product fluid flowing out of the second reactor. Controlling the flow rate of the oxidant to be supplied to the second oxidant supply means based on the temperature measured by the second thermometer to control the temperature of the second reaction product fluid to the target temperature. The batch type supercritical water reactor according to claim 1, further comprising a two-temperature controller. 3. A means for returning a part of the first reaction product fluid to the first reactor, cooling the remaining part of the first reaction product fluid, gas-liquid separation, and heating the obtained water by pressurization. 3. A batch type supercritical water reactor according to claim 1, further comprising means for feeding water as a part of the supercritical water to the first reactor.