JP2612249B2 - Method and apparatus for hydrothermal reaction treatment of environmental pollutants - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for hydrothermal reaction treatment of environmental pollutants. The pressure in the hydrothermal reactor is maintained constant by interlocking with the operation of the cylinder pump that supplies the water to the reactor, and the necessary and sufficient hydrothermal reaction is continuously and stably performed.

[0002]

2. Description of the Related Art Detoxification of environmental pollutants such as CFCs has become a global concern in order to protect the global environment, and several means have been provided. For example, a hydrothermal reaction method, an incineration method, an explosive reaction decomposition method, and a plasma reaction method have been proposed for a chlorofluorocarbon treatment method.

[0003] Among these, the hydrothermal reaction method is not limited to chlorofluorocarbon gas, but is versatile for general environmental pollutants, mainly organic waste such as trichlene, waste oil, dioxin, PCB, and manure. It is attracting attention as a processing method with a certainty. In this hydrothermal reaction method, for example, CFCs can be decomposed into 100% safe substances such as sodium chloride and carbon dioxide.

[0004] Regarding the apparatus for realizing the hydrothermal reaction method, in a laboratory, processing experiments using an autoclave (mixing ratios of liquids such as a ratio of caustic soda, ethanol, and chlorofluorocarbon liquid, set values of temperature, and pressures) were carried out. Experiments are performed on the set value and the set value of the reaction time), but none of them has been provided as a practical machine except in the laboratory.

Therefore, in order to provide a practical machine for realizing the hydrothermal reaction method, it is conceivable to scale up the apparatus at the laboratory stage, but in this case, there are the following disadvantages. In other words, (1) a batch-type process (2) a pressure vessel makes maintenance and management difficult and expensive.
(3) Since the thermal energy cannot be recovered, the running cost is high. (4) The throughput is small. (5) It is difficult to control the pressure and temperature. For this reason, the development of a practical machine for realizing the hydrothermal reaction method is not a scale-up of a laboratory-stage device, and the development of another alternative device is required.

In the development of this alternative apparatus, a known slurry pump composed of a cylinder pump is used to supply a treatment liquid containing environmental pollutants to the hydrothermal reactor so that the hydrothermal reaction can be continuously performed. In addition, it is conceivable to attach a pressure regulating valve to the hydrothermal reactor to continuously discharge the water. In this case, the pressure regulating valve urges the discharge port with a constant force spring, and when the pressure of the processing solution from the hydrothermal reactor exceeds the spring force, the pressure is opposed to the spring force.
It is configured to be discharged from the discharge port.

To explain the conventional pressure regulating valve 50, as shown in FIG. 9, a valve seat 54 is provided on the inlet side in a port 53 where an inlet 51 and an outlet 52 communicate with each other at right angles. The valve body 55 faces the seat 54 and the sleeve 5
6 and slidably disposed therein, and is configured to be pressed against the valve seat 54 by a spring 57 inserted into a sleeve 56. A spring 57 is attached to the sleeve 56.
An adjustment screw 58 is provided for manually adjusting the spring force. Therefore, when pressure against the spring force of the spring 57 is applied to the valve body 55, the valve body 55 separates from the valve seat 54, and the processing liquid flows into the port 53 and reaches the outlet 52.

[0008]

However, when the pressure regulating valve 50 using only the spring force of the spring 57 is used, the characteristic of the pressure regulating valve 50 is linked to the movement of the cylinder pump in the hydrothermal reactor as shown in FIG. Pressure fluctuations occur. This is due to the characteristic of the conventional pressure regulating valve 50, as shown in FIGS. 11 and 12, which is caused by a change in the holding pressure when the flow rate changes.

That is, in FIG. 11, when the pump discharge amount changes from V _{0 to 0} when the spring pressing amount is constant, the pressure changes from P _{0 to} P ₁ . In FIG. 12, when the set flow rate V ₀ , the point where the spring pressing amount L ₀ is required is the action point. Here, the pump discharge amount becomes V ₀ →
0 When changes, because moving along the arrow a, the amount of push spring, it is necessary to change from L ₀ to Lmax. Further, when changing the 0 → V _0, the amount of press spring varies along the arrow b becomes necessary to change from Lmax to L _0. However, only, it is a condition for maintaining the pressure P ₀ constant.

[0010] This leads to the following disadvantages. (1) Since the chemical reaction conditions cannot be kept constant, the decomposition treatment becomes unstable, and the untreated liquid is discharged. (2) The reaction time cannot be stably maintained, and the same result as (1) is obtained. (3) It is difficult to arbitrarily change the processing amount. (4) As the amount of processing increases, the amount of change increases, so that processing beyond a certain amount cannot be performed. (5) Due to this fluctuation, the temperature is increased more than necessary or the pressure is increased more than necessary so that the reaction proceeds even at the lowest point, so that the loss increases.

Accordingly, the present invention provides a hydrothermal reaction treatment for environmental pollutants which can be continuously performed by improving a pressure regulating valve using only the spring force of a spring and which can be continuously discharged. A method and apparatus are provided.

[0012]

In order to achieve the above object, the present invention relates to a cylinder pump for supplying a processing liquid to a hydrothermal reactor by controlling the flow rate of the processing liquid after the hydrothermal reaction processing of an environmental pollutant such as chlorofluorocarbon. The hydrothermal reaction of environmental pollutants is characterized by keeping the pressure inside the hydrothermal reactor constant and performing the necessary and sufficient hydrothermal reaction process continuously and stably by adjusting in conjunction with the operation of Provide a processing method.

[0013] Further, a cylinder pump for supplying a mixed solution containing environmental pollutants such as chlorofluorocarbon to a hydrothermal reactor, a heat exchanger, a hydrothermal reactor, a cooler, and a fluid control device connected to the cooler. For hydrothermal reaction of environmental pollutants, comprising:

The pressure regulating valve has a spring for pressing a valve body against a valve seat, and has a servo driver for changing the spring force of the spring by a signal from a means for detecting the movement of the cylinder pump. The present invention provides a hydrothermal reaction apparatus.

[0015]

[Function] Since the pressure regulating valve changes the flow rate of the processing liquid in conjunction with the movement of the cylinder pump, the pressure of the processing liquid supplied to the hydrothermal reactor becomes stable, and the pressure in the hydrothermal reactor becomes constant. This enables the necessary and sufficient hydrothermal reaction treatment to be continuously and stably performed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 shows a flow chart of a chlorofluorocarbon processing system. A tank 1 contains a mixed liquid of chlorofluorocarbon liquid, caustic soda liquid and ethanol, which is sent to a heat exchanger 5 through a pipe 4 via a flow meter 3 by a pump 2 and a pipe 4. , A reaction in the hydrothermal reactor 6, the heat is again sent to the cooler 7 through the heat exchanger 5, the water is sent from the cooler 7 to the separator 9 through the pressure control valve 8 for fluid control, and the separator 9 cleans It separates into water and clean products. The tank 1a, the pump 2a and the flow meter 3a are
Depending on the type of CFC gas, it is gasified at room temperature, so this system is used at this time.

As the pumps 2 and 2a, conventionally known slurry pumps are used. That is, as shown in FIG. 2, the pipes 12a and 12b are connected to the vicinity of both ends of the cylinder pump 10 via check valves 11a and 11b on one side, respectively, and these pipes 12a and 12b are collectively connected to the pipe 13. Pipes 14a and 14b are connected to the tanks 1 and 1a via check valves 11c and 11d on the other side near both ends of the cylinder pump 10, respectively, and these pipes 14a and 14b are collectively connected to a pipe 15a. To the hydrothermal reactor 6.

A shaft 18 is connected to a piston 17 inserted into the cylinder pump 10.
Has a free end at one end and a driving cylinder 19 connected to the other end. The driving cylinder 19 is arranged at a predetermined interval from the cylinder pump 10 and is a device that reciprocates the shaft 18 in the axial direction. A coupling 20 is provided on a shaft 18 between the cylinder pump 10 and the driving cylinder 19, and limit switches 21 and 22 that are opened and closed when the coupling 20 abuts are provided.

This slurry pump has a high pumping force, is stable, is small in size, is easy to operate, and has a high reliability because of its simple structure. It is widely used as a cylinder for pumping high-concentration slurries such as acid, alkaline slurries and the like.

Next, as the pressure regulating valve 8, as shown in FIG. 3, a valve seat 27 is provided on the inlet side in a port 26 in which an inlet 24 and an outlet 25 communicate with each other at right angles. The valve body 28 is slidably disposed in the sleeve 29 and is pressed against the valve seat 27 by a spring 30 inserted into the sleeve 29. The one provided with the adjusting screw 31 for adjusting the force is used. An actuator 33 of, for example, an AC servomotor 32 is connected to the adjusting screw 31 as a servo driver.

Further, as shown in FIG. 4, the movement (position detection or speed detection) of the cylinder pump 10 is detected by, for example, a rotary encoder 34 (a linear resistor may be used). , An AC servomotor 32 attached to the pressure regulating valve 8 and an actuator 33
Is controlled to change the pressing amount of the spring 30 of the pressure adjusting valve 8.

As shown in FIG. 5, the hydrothermal reactor 6 enters the inlet 35 from the pump 2 via the heat exchanger 5 and the pipe 37 meanders so as to be discharged from the outlet 36.
And a band heater 38 wound therearound. As shown in FIG. 6, the band heater 38 generates heat when an electric heating coil or the like is housed in a cylindrical body 39 surrounding the outer peripheral surface of the pipe 37 and connected to a power supply 40. The necessary number of band heaters 38 are arranged at appropriate intervals in the longitudinal direction of the pipe 37. The band heater 38 is controlled by the control unit A so that the temperature inside the pipe 37 becomes constant.

Next, the operation of the above embodiment will be described.
In, the mixed solution enters the inlet 35 of the hydrothermal reactor 6 from the pump 1 via the heat exchanger 5, is heated by a band heater 38 wound around a pipe 39, and is pressurized to a constant pressure. The hydrothermal reaction is performed in a state where the temperature is controlled to be constant, and the mixed liquid after the hydrothermal reaction is discharged again from the outlet 36 through the heat exchanger 5, the cooler 7, the pressure regulator 8 to the separator 9. Is done.

In the pressure regulating valve 8 of the present invention, the movement of the cylinder pump 10 is detected by the rotary encoder 34 as described above, and the amount of pressing of the spring 30 is changed by the AC servomotor 32 based on this signal. Configuration. Therefore, the spring pressing amount is changed according to the flow rate. For example, in FIG. 7, t ₂ ~t ₃ and t ₅
In between ~t ₆ increased from the flow rate decreases the amount of push spring, to reduce the amount of pressing spring because the flow rate increases at between t ₃ ~t ₄ and t ₆ ~t _7.

Therefore, this timing and the amount of rotation are
As shown in FIG. 7, if properly selected, the pressure fluctuation in the hydrothermal reactor 6 can be made very small. Further, when the rotation amount and the pressure change are stored and fed back to the next rotation control, control for automatically determining the optimum rotation amount becomes possible. In the control of the embodiment, 300 ± 70 kg before the control
, But could be reduced to a change of 300 ± 5 kg. Further, even if the flow rate is arbitrarily changed during the process, control can be performed so that the set pressure is automatically set within a range that the spring 30 can handle.

As shown in FIG. 8, if the pumps 2 and 2a are selected so that the discharge amount decreases as the pressure increases, the speed of the cylinder pump 10 decreases, so that the control amount of the pressure regulating valve 8 decreases. Since the relationship between the cylinder position and the speed can also be used to detect troubles such as clogging of foreign substances on the way, there is an advantage that measures such as releasing the valve body 28 can be automated.

According to the embodiment, when the spring pressing amount of the pressure regulating valve is fixed and fixed as in the prior art, when P ₀ = 300 kgm / cm ² , P ₁ = 52 kgm / cm ² . According to the apparatus of the present invention, when P ₀ = 300 kgm / cm ² , ΔP = ± 2.1 kgm / cm ² (ΔP is t _{2 to} t ₃ in the pressure change in the hydrothermal reactor in FIG. 7). and t ₅ the recess depth of ~t ₆ or t ₃ ~t ₄ and convex height between t ₆ ~t ₇₎ become.

[0028]

According to the present invention described above, the flow rate of the processing liquid after the hydrothermal reaction processing of the environmental pollutants such as chlorofluorocarbon is linked to the operation of the cylinder pump for supplying the processing liquid to the hydrothermal reactor. By adjusting the pressure regulating valve, the pressure in the hydrothermal reactor can be kept constant, and therefore,
The necessary and sufficient hydrothermal reaction can be continuously and stably performed. As a result, the pressure fluctuation in the hydrothermal reactor can be made extremely small, the processing liquid is not discharged in an untreated state, and can be arbitrarily changed even if the processing amount changes.

[Brief description of the drawings]

FIG. 1 is a flow chart of a hydrothermal reaction processing system.

FIG. 2 is a plan view showing a pump.

FIG. 3 is a sectional side view of the pressure regulating valve.

FIG. 4 is a schematic diagram of a main part of the present invention.

FIG. 5 is a plan view of a hydrothermal reactor.

FIG. 6 is a perspective view of a part of a hydrothermal reactor.

FIG. 7 is a graph showing a discharge amount of a cylinder pump, a spring pressing amount of a pressure regulating valve, and a pressure in a hydrothermal reactor.

FIG. 8 is a schematic diagram (A) and a characteristic diagram (B) showing another example of the pump.

FIG. 9 is a sectional view of a conventional pressure regulating valve.

FIG. 10 is a graph showing the cylinder speed, the discharge amount from the pressure control valve, and the pressure in the hydrothermal reactor when a conventional pressure control valve is used.

FIG. 11 is a discharge amount-pressure characteristic diagram when a spring pressing amount is constant.

FIG. 12 is a graph showing a relationship between a flow rate and a spring pressing amount when the pressure is fixed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tank 2 ... Pump 3 ... Flow meter 4 ... Piping 5 ... Heat exchanger 6 ... Hydrothermal reactor 7 ... Cooler 8 ... Pressure regulating valve 9 ... Separator 22,23 ... Limit switch 27 ... Valve seat 28 ... Valve Body 30 Spring 32 AC servo motor (servo driver) 34 Rotary encoder

Claims (8)

(57) [Claims] 1. A hydrothermal reaction by adjusting the flow rate of a treatment liquid after a hydrothermal reaction treatment of an environmental pollutant such as chlorofluorocarbon in conjunction with the operation of a cylinder pump for supplying the treatment liquid to a hydrothermal reactor. A hydrothermal treatment method for environmental pollutants, characterized in that the pressure inside the vessel is kept constant and the necessary and sufficient hydrothermal reaction treatment is performed continuously and stably. 2. A cylinder pump for supplying a mixture containing an environmental pollutant such as chlorofluorocarbon from a tank to a hydrothermal reactor, a heat exchanger, a hydrothermal reactor, a cooler, and a fluid connected to the cooler. A hydrothermal treatment apparatus for environmental pollutants, comprising a pressure regulating valve for control. 3. The pressure regulating valve according to claim 2, further comprising a spring for pressing the valve body against the valve seat, and a servo driver for changing a spring force of the spring by a signal of a means for detecting the movement of the cylinder pump. Hydrothermal treatment equipment for environmental pollutants. 4. The hydrothermal treatment apparatus for environmental pollutants according to claim 3, wherein the means for detecting the movement of the cylinder pump is a rotary encoder. 5. The hydrothermal treatment apparatus for environmental pollutants according to claim 3, wherein the means for detecting the movement of the cylinder pump is a limit switch. 6. The hydrothermal treatment apparatus for environmental pollutants according to claim 3, wherein the servo driver is an AC servomotor. 7. The cylinder pump is of a pressure compensation type in which when the discharge pressure reaches the pressure set by the compensator, the discharge amount automatically decreases and the set pressure is maintained. 7. The apparatus for hydrothermal reaction treatment of environmental pollutants according to 6. 8. A hydrothermal reactor in which a band heater is wound around an outer peripheral surface of a pipe.
3. The hydrothermal reaction apparatus according to claim 1.