JPH11290678A - Treatment of organic matter using hypercritical and hydrothermal reaction process and treatment plant therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain the diversion of an inorganic content separated by deposition into a downstream by making a liquid content in the upper part of the interior of a separator stagnant and causing the deposition of the inorganic content even near the upper part and, at the same time, sending the stagnant liquid content to downstream. SOLUTION: An ejection sleeve 44 is of such a construction that the inner diameter of the sleeve 44 is larger than the flow path of an intake 4a to reduce the velocity of a material to be treated by a chemical reaction flowing into a separator and subject the material to a vacuum pressure. In addition, a guide part 45 is shaped like an umbrella having a larger outer diameter than the inner diameter of the lower opening of the ejection sleeve 44, and at the same time, guides a fluid ejected from the ejection sleeve 44 to the outside by the help of a tapered face 45a. Further, the guide part 45 obstructs an ascending stream near the center part on account of a tapered face 45b facing downward, and again conducts the ejected fluid to the outside. A support member 46 has at least a communicating hole 46a for sending an inorganic matter or the like to a discharge outlet 4b, near the inner bottom part of a pressure-resistant container 41 and an atmosphere which makes the fluid stagnant is formed in a hollow hole 46b connected to the discharge outlet 4b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a hydrothermal reaction processing method and a processing plant therefor.

[0002]

2. Description of the Related Art As a technique for decomposing organic substances harmful to humans and animals with water under supercritical conditions to render them harmless, Technical Example 1: Japanese Patent Application Laid-Open No. 07-275870, "Supercritical hydroxylation treatment of harmful organic substances" Apparatus and Treatment Method "and Technical Example 2: Japanese Patent Application Laid-Open No. 07-275871 entitled" Method and Apparatus for Supercritical Hydroxidation Treatment of Hazardous Substances ".

The technical example 1 includes a reactor for decomposing harmful organic substances under a supercritical condition of water, a gas-liquid separator for gas-liquid separation of decomposition products, And a separate pressurizing means for supplying water to the reactor under pressure and a return means for refluxing the separated liquid of the gas-liquid separator to the first pressurizing means. The technical example 2 includes a preheater, a reactor, a cooler, and a gas-liquid separator, and performs a decomposition treatment of harmful substances under supercritical conditions of water. Separate and feed the aqueous solution to the preheater to preheat,
The technology of mixing the preheated aqueous solution and the harmful substance at the inlet of the reactor is adopted.

[0004]

However, the object to be treated (liquid organic substance to be treated) which is subjected to the supercritical / hydrothermal reaction treatment is often a miscellaneous liquid having an inhomogeneous property. After or during the supercritical / hydrothermal reaction process,
It is necessary to take measures against the phenomenon that the inorganic component (inorganic suspension) is separated and deposited to block pipes and valves, and that the flow path is narrowed.

[0005] The present invention has been made in view of such problems, and achieves the following objects. Decompression and deceleration of the reaction product after the supercritical / hydrothermal reaction treatment promotes the precipitation of inorganic components and chlorides, and efficiently separates inorganic components from liquid components. Suppressing the downstream of the separated and separated inorganic components. To limit the range of occurrence of soaring phenomena of extracted and separated inorganic components and promote reprecipitation and sedimentation.

[0006]

The liquefied object containing an organic substance is sent to a supercritical / hydrothermal reaction processing means and subjected to a hydrothermal reaction in a supercritical atmosphere. The reaction product produced by the means is sent to the separator, and the reaction product is ejected from the ejection sleeve into the inside of the separator, and the inorganic component in the reaction product is precipitated by decompression based on the increase in cross-sectional area. Thus, the separation of the inorganic component from the liquid component is promoted, and the liquid component from which the inorganic component has been separated is sent downstream. At that time, the liquid component was once guided downward, and the precipitated inorganic component was sent to the bottom of the separator, whereby the liquid component in the upper inside of the separator was stagnated, and the inorganic component was also precipitated in the vicinity thereof, A technique of sending the liquid portion in the stagnant portion downstream is adopted. The precipitated inorganic components in the stagnant portion gradually settle down and are sent to the bottom by the downward flow inside the separator. A drain port is provided at an upper position inside the separator, and a liquid component separated from the inorganic component is sent downstream. Inside the separator, an ejection sleeve that sends the reaction treatment product downward while decompressing and decelerating, and a guide portion that is arranged at an interval below the lower ejection port of the ejection sleeve and diffuses the downward flow outward. Are arranged, and the guide portion is
An umbrella-shaped one is adopted, the surface facing the sleeve is a tapered surface, and the lower surface is lowered to intersect with the upward flow of the reaction processed material near the center and convert it to a downward flow. It is a tapered surface. Also, on the inner wall of the separator,
An inwardly-flanged flange-like stopper for lowering the upward flow along the outer side toward the inner side is provided, and the stopper is disposed at intervals of a plurality of stages along the inner wall of the separator.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a supercritical hydrothermal treatment plant according to the present invention will be described below with reference to FIGS. FIG. 1 shows the overall configuration of a supercritical / hydrothermal reaction processing plant.

The supercritical / hydrothermal reaction processing plant X is shown in FIG.
As shown in FIG. 2, a raw liquid supply means 1 for supplying the liquid organic substance a to be processed under a pressure required for the supercritical / hydrothermal reaction treatment, for example, up to 20 MPa, is connected to the raw liquid supply means 1. A preheater 2 for preheating in advance;
Supercritical / hydrothermal reaction processing means 3A and 3B connected to the preheater 2 for performing a hydrothermal reaction with the liquid organic substance a to be treated in a supercritical condition atmosphere, and a preheater 2 and a supercritical / hydrothermal reaction processing means Separator 4 connected to 3A, 3B for separating the supercritical / hydrothermal reaction product into solids (suspension) and liquids 4
A, 4B, 4C, and discharge means 5 connected to the separators 4A, 4B, 4C for returning the suspended matter (solid content) to a reduced pressure state and discharging the same, and the most downstream separator 4C has a treated water treatment means 6 for taking out and treating the liquid component.
Is connected.

[0009] The liquid organic substance a to be treated is converted into harmful organic substances such as chlorofluorocarbons and PCBs described in Technical Examples 1 and 2, and organic wastes such as sludge and pulp sludge.
It is obtained by adding and adjusting an appropriate amount of water necessary for the hydrothermal reaction treatment.

As shown in FIG. 1, the stock solution supply means 1 comprises a stock solution tank 11 for storing a liquid organic substance a to be treated at, for example, an atmospheric pressure or a relatively low pressure, And a supply pump 12 for sucking and supplying the pressure by, for example, the above-mentioned pressure of about 20 MPa.

As shown in FIG. 1, the preheater 2 is interposed between the stock solution supply means 1 and the supercritical / hydrothermal reaction treatment means 3A to preheat the liquid organic substance a to be treated to, for example, about 200 ° C. In this state, the liquid organic substance a is sent to the supercritical / hydrothermal reaction processing means 3A in a normal case, and the liquid organic substance a to be processed is sent to the downstream separator 4A when the inorganic content is large.

The supercritical / hydrothermal reaction processing means 3A, 3B
Comprises a first reaction tank 31A and a second reaction tank 31B arranged in series downstream of the preheater 2;
A and the second reaction tank 31B are heated to a temperature of, for example, about 350 ° C., so that the liquid organic substance a
And a heating furnace 32 for causing a hydrothermal reaction in a supercritical condition atmosphere.

As shown in FIG. 1, the separator 4A is connected to the downstream of the preheater 2 and the upstream of the first reaction tank 31A, and the separator 4B is connected to the downstream of the first reaction tank 31A. And the upstream side of the second reaction tank 31B.
C is connected to the downstream of the second reaction tank 31B.

Regarding the details of the separators 4A, 4B, 4C,
This will be described with reference to FIGS. Separators 4A, 4B,
4C, as shown in FIG. 2, a pressure-resistant container 41 which is directly connected to the preheater 2 and the first and second supercritical / hydrothermal reaction processing means 3A, 3B to receive a fluid in a high-pressure state; An outer wall 42 surrounding the pressure vessel 41, a heat insulating material 43 interposed between the pressure vessel 41 and the outer wall 42,
1, and an umbrella-shaped guide portion which is arranged in an inserted state inside the nozzle 1, and which is disposed at an interval below the ejection port of the squirt sleeve 44 and diffuses a downward flow at the center of the pressure-resistant container 41 to the outside. What has the support member 46 arrange | positioned between 45 and the inner bottom part of the pressure-resistant container 41 in order to support this guide part 45 and to set the position (height) is applied.

The pressure-resistant container 41 has an inlet 4a for receiving the reaction product and sending it into the ejection sleeve 44, and an outlet 4 for extracting the inorganic component for extracting the inorganic component.
b, an outflow path 4c and a drainage port 4d for sending the liquid after the separation of the inorganic components to the next supercritical / hydrothermal reaction processing means 3A, 3B or the treated water processing means 6.

The ejection sleeve 44 is set to have a larger inner diameter than the flow path of the inlet 4a so that the reaction product flowing into the separators 4A, 4B, 4C is decelerated and decompressed.

The guide portion 45 is formed in an umbrella shape having an outer diameter larger than the inner diameter of the lower opening of the ejection sleeve 44 and has a tapered surface 4 facing the ejection sleeve 44.
5a guides the fluid ejected from the ejection sleeve 44 to the outside, and is configured to prevent the upward flow near the center by the tapered surface 45b facing downward, and to guide the fluid outward again.

The support member 46 has a communication hole 46a at least near the inner bottom of the pressure-resistant container 41 for sending out inorganic substances and the like to the discharge port 4b.
In the hollow hole 46b which is in a connected state, an atmosphere for retaining the fluid is formed.

As shown in FIG. 1, the discharge means 5 is arranged in a connected state downstream of each of the separators 4A, 4B, 4C.
An inlet 5a for receiving an inorganic component (solid content) in a supercritical and high pressure (for example, a pressure of about 20 MPa), and an inorganic component (inorganic suspension) intermittently returned to a reduced pressure state of about atmospheric pressure and downstream. Suspended material discharge port 5
b, and a gas outlet 5c for sending the gas component separated inside to an appropriate gas processing means.

As shown in FIG. 1, the treated water treatment means 6 is connected to a separator 4C located at the most downstream position, and is a liquid such as treated water generated by separation by the separator 4C. A pump having a pump function of sucking a liquid is applied, and a pump having a function of storing a collected liquid is applied.

In FIGS. 1 and 2, b indicates a switching valve, c indicates a control valve, and d indicates a back pressure valve.

In such a hydrothermal reaction processing plant X,
The undiluted solution supply means 1 is operated to supply the liquid organic substance a to be treated at a desired pressure of about 20 MPa to the preheater 2, for example, heating (preheating) to a temperature before the critical state (for example, about 200 ° C.). From the supercritical / hydrothermal reaction processing means 3A
To generate the desired supercritical / hydrothermal reaction.

At this time, when the inorganic component is separated or precipitated from the liquid organic substance a to be treated, or when the amount of the separated inorganic substance is large, the preheated liquid organic substance a to be treated is switched by switching the switching valve b. A step of sending the liquid component to the separator 4A to separate the inorganic component from the liquid organic material a to be treated is employed. Since the preheater 2 does not reach a high temperature until the supercritical state is reached, the inner diameter of the ejection sleeve 44 is set relatively small inside the corresponding part of the separator 4A so as to reduce the pressure drop. It is set to be large so that a large amount of the liquid organic substance a to be treated is gently inserted.

The liquid organic substance a to be treated in the preheated state sent to the supercritical / hydrothermal reaction processing means 3A is heated by the operation of the heating furnace 32 to an appropriate temperature at which the supercritical / hydrothermal reaction is generated (for example, under the above-mentioned conditions of 20 MPa). At a temperature of about 350 ° C.). When these high-temperature and high-pressure conditions and the conditions in which water is interposed (mixed) in the liquid organic substance a to be treated overlap, a hydrothermal reaction occurs in a supercritical environment, and the organic substances are decomposed in composition. The phenomenon of dissolution in water is promoted. At this time, the mixture of the organic matter (the above-mentioned carbon compound such as chlorofluorocarbon, PCB, sludge, and pulp sludge) and water are almost uniformly dissolved in water in a supercritical environment.

In the first stage supercritical / hydrothermal reaction treatment means 3A, if a sufficient temperature cannot be obtained and the state does not reach a critical state, or if the decomposition and precipitation of inorganic components are large, the supercritical / water The switching valve b on the downstream side of the thermal reaction processing means 3A is switched so that the liquid is sent from the separator 4B to the supercritical / hydrothermal reaction processing means 3B at the next stage to perform the supercritical / hydrothermal reaction processing. Therefore, the supercritical / hydrothermal reaction processing means 3A, 3B
Can be three or more stages.

Preheater 2 and supercritical / hydrothermal reaction processing means 3
In FIGS. 3A and 3B, the reaction products generated by the heating or the supercritical / hydrothermal reaction process pass through the inlet 4a and the ejection sleeve 44, and are directed toward the guide portion 45 as shown by an arrow in FIG. It is squirted. At this time, since the inner diameter of the pressure-resistant container 41 is larger than that of the ejection port of the ejection sleeve 44, deceleration and decompression are performed. It is considered that the supercritical state disappears due to the reduced pressure, and inorganic components (silica component, salt component, etc.) in the reaction product precipitate and gradually settle, and deposit on the inner bottom of the pressure-resistant container 41.

On the other hand, as shown in FIG.
It abuts against the tapered surface 45a of the guide portion 45 and is guided to the outside, and is sent into the inner bottom portion of the pressure-resistant container 41, and a part of the upward flow flows into the hollow hole 46b of the support member 46, and the flow is blocked and stagnated. I do. Therefore, based on the decompression and deceleration, the bottom of the pressure-resistant container 41 and the hollow
It is conceivable that the precipitation of the inorganic component frequently occurs at the portion 6b and gradually settles, and the inorganic component accumulates near the outlet 4b. The liquid component (most of the reaction product) from which the inorganic component has been separated,
The liquid is sent downstream from the liquid discharge port 4 d located inside the pressure-resistant container 41.

The reaction product is a supercritical / hydrothermal reaction processing means 3
In the case of passing through A and 3B, the inorganic components generated by the supercritical / hydrothermal reaction mainly precipitate and settle and separate. In the case where the reaction product is sent out from the preheater 2, the inorganic component mixed into the material to be processed is necessarily deposited and separated based on the fact that the reaction product does not pass through the supercritical / hydrothermal reaction process. Although not necessarily, solids,
If there are some inorganic components that have precipitated (or separated) without going through a supercritical hydrothermal reaction, they will settle. These inorganic components are transferred further downstream from the discharge port 4b of the pressure-resistant container 41 by opening the control valve c.

The inorganic components separated and deposited or separated by the separators 4A, 4B, 4C are transferred to the discharging means 5 by opening the control valve c between the inorganic means and the discharging means 5. In the discharge means 5, after the control valve c between the separators 4A, 4B, and 4C is closed and separated, the processing required for the inorganic component is performed by returning to a low-pressure environment of, for example, about atmospheric pressure. Do. In the discharging means 5, the C generated by the pressure drop
The gas components such as O ₂ and water vapor are processed by the gas processing means of the above-described example.

FIGS. 4 and 5 show the separators 4A, 4B and 4C.
In the second embodiment. In the second embodiment, an inward flange-shaped stopper 47 whose inside is lowered is disposed on the inner wall of the pressure-resistant container 41 and above the ejection port of the ejection sleeve 44. When the stopper 47 is provided, the flow of the reaction product ejected from the ejection sleeve 44 is converted from a downflow at the center to an upflow outside as shown by arrows in FIG. In this case, the flow returns to the descending flow again, and it is possible to suppress the occurrence of the phenomenon that the inorganic component precipitated by the reduced pressure of the reaction product is directly sent to the drain port 4d and discharged from the pressure-resistant container 41. it can.

[Other Embodiments] The present invention also includes the following techniques. a) Both the guide portion 45 and the stopper 47 are provided inside the pressure-resistant container 41. b) The stoppers 47 are arranged in multiple stages with a vertical interval.

[0032]

According to the supercritical / hydrothermal treatment method for organic matter and the treatment plant thereof according to the present invention, the following effects can be obtained. (1) The reaction product after the supercritical / hydrothermal reaction treatment is ejected from the ejection sleeve of the flow separator to perform decompression and deceleration, and to keep the liquid content in the upper part of the separator stagnant. In addition, it promotes precipitation of inorganic components and chlorides, and can efficiently separate inorganic components from liquid components. (2) The liquid component in the upper part of the separator is stagnated, the inorganic component is precipitated in the vicinity thereof, and the liquid component in the stagnant portion is sent downstream, so that the separated inorganic component can be sent downstream. Can be suppressed. (3) The umbrella-shaped guide portion feeds the liquid component to the bottom of the separator, and the upward flow generated at the center is stagnated at the lower portion of the guide portion, so that the inorganic component precipitated in the lower half of the separator is downstream. Can be sent smoothly. (4) By arranging a stopper on the inner wall of the separator to stop the rising flow, the range of occurrence of the rising phenomenon of the extracted and separated inorganic component can be limited, and re-precipitation and sedimentation can be promoted.

[Brief description of the drawings]

FIG. 1 is a connection diagram showing a first embodiment of a supercritical / hydrothermal reaction treatment method for organic matter and a treatment plant therefor according to the present invention.

FIG. 2 is a front sectional view showing a detailed structure of the separator of FIG.

FIG. 3 is a front cross-sectional view schematically illustrating a reduced pressure state by the separator of FIG. 2;

FIG. 4 is a front sectional view showing a second embodiment of a part of a separator.

FIG. 5 is a front sectional view schematically showing a reduced pressure state by the separator of FIG. 4;

[Explanation of symbols]

 X Supercritical / hydrothermal reaction treatment plant a Liquid organic matter to be treated 1 Raw liquid supply means 2 Preheater 3A, 3B Supercritical / hydrothermal reaction treatment means 4A, 4B, 4C Separator 4a Inlet 4b Outlet 4c Outflow path 4d Discharge Liquid port 5 Discharge means 5a Injection of treated material 5b Suspended matter discharge port 5c Gas discharge port 6 Treated water treatment means 11 Raw liquid tank 12 Supply pump 31A First reaction tank 31B Second reaction tank 32 Heating furnace 41 Pressure-resistant container 42 Outer wall part 43 Insulation material 44 Ejection sleeve 45 Guide part 45a, 45b Tapered surface 46 Support member 46a Communication hole 46b Hollow hole 47 Stopper b Switching valve c Control valve d Back pressure valve

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Keiichi Miwa Ishikawashima-Harima Heavy Industries Co., Ltd.

Claims (7)

[Claims] A step of subjecting the object to be treated (a) to a supercritical / hydrothermal reaction;
4) spouting into the inside of the separators (4A to 4C), the step of precipitating the inorganic component in the reaction product by depressurization at the time of jetting and separating it into the inorganic component and the liquid component, A step of guiding the flow once downward, forming an ascending flow, and stagnating the ascending flow. 2. The supercritical / hydrothermal treatment method for organic matter according to claim 1, wherein the downward flow of the reaction product is guided outward from the center, and then the upward flow formed at the center is stopped. . 3. The method according to claim 1, further comprising a step of converting the reaction product into a downward flow along the center, a step of subsequently converting the reaction processing product into an outward upward flow, and a step of bringing the upward flow toward the center and stopping the upward flow. The supercritical / hydrothermal treatment method for organic substances according to claim 1 or 2. 4. A supercritical / hydrothermal reaction means (3A, 3B) for causing a supercritical / hydrothermal reaction of the object (a), and a reaction generated by being connected to the supercritical / hydrothermal reaction means. Separators (4A, 4B, 4) for separating the processed material into inorganic and liquid components
C), wherein the separator comprises: an ejection sleeve (44) for ejecting the reaction product into the separator to deposit inorganic components in the reaction product by depressurization; and a lower portion than the ejection sleeve. A supercritical / hydrothermal reaction plant for organic matter, comprising: a guide portion (45) arranged at an interval to diffuse a downward flow outward. 5. A lower surface of the guide portion (45) is formed with a tapered surface (45b) having a lower outer side for converting into a downward flow while intersecting with the upward flow of the reaction processing substance near the center. Item 4. A supercritical / hydrothermal treatment plant for organic matter according to Item 4. 6. A supercritical / hydrothermal reaction means (3A, 3B) for causing a supercritical / hydrothermal reaction of the object (a), and a reaction generated by being connected to the supercritical / hydrothermal reaction means. Separators (4A, 4B, 4) for separating the processed material into inorganic and liquid components
C), wherein the separator comprises: an ejection sleeve (44) for ejecting the reaction product into the interior of the separator to deposit inorganic components in the reaction product under reduced pressure; and a separator (4A, 4B,
4C) A supercritical hydrothermal reaction plant for organic matter, comprising an inward flange-shaped stopper (47) disposed on the inner wall of 4C) for stopping the ascending flow along the outside toward the inside. 7. The supercritical hydrothermal treatment plant for organic matter according to claim 6, wherein the stoppers (47) are arranged at a plurality of vertical intervals.