TW201435294A - Method for reclaiming high explosive from warhead by striping down in supercritical fluid - Google Patents

Abstract

A method for the strip down of an explosive component from a high explosive, comprising the steps of loading a high explosive containing an explosive component into a striping down vessel; supplying a supercritical fluid to the striping down vessel; contacting the high explosive with the supercritical fluid at a temperature below the melting point of the explosive component and at a pressure sufficient to strip down the explosive component; and inducing a sonicating process on the striping down vessel simultaneously at a frequency of 0.01MHz to 10MHz.

Description

Method for removing warhead by supercritical fluid

The invention relates to a method for separating a warhead of a supercritical fluid, in particular to a trimethyl toluene (2-methyl-1,3,5-trinitrobenzene, TNT) in a supercritical carbon dioxide fluid batch under low temperature conditions. Separation method for separation and drug removal.

How to safely and effectively remove abandonment of military ammunition from the active arsenal has received significant attention, and the abolition of militarization plans is usually concentrated on discarding or destroying. Recently, based on environmental protection, efforts have been made to develop methods for recycling and/or recycling, so that explosives and higher value components of the armament system can be recovered and reused in military applications.

The traditional abolition of military ammunition separation technology involves the separation of high-energy explosives from the launching shell by means of melting, steam/water washing and solvent washing. Typical melting and steam/water washing methods are usually above the melting point of the ammunition. The temperature causes the high-energy explosive to change from a solid to a liquid phase, and the solvent elution method is to dissolve the high-energy explosive to separate it. The disadvantages of the three methods are that the processing is time-consuming, and it is not suitable for a large amount of explosives, and the resulting A large amount of polluted wastewater requires a large cost to be reprocessed, so that the treatment efficiency is low.

Morris, inventor of U.S. Patent No. 5,953,679, discloses a method for extracting trinitrotoluene (TNT) from a high energy explosive comprising a temperature above the melting point of trinitrotoluene (e.g., 85 ° C) and a pressure sufficient to extract trinitrotoluene (eg, 37.4 MPa), the high energy explosive is contacted with a supercritical fluid.

The aforementioned patents are part of the extraction process, in detail, the specific substances in the mixture are moved from one solvent to another due to the different solubility of the different solvents. In the first example of the case, it is explained that the solubility of trinitrotoluene and Hexogeon (RDX, Hexogeon) in a supercritical carbon dioxide solvent is carried out; in the second and third examples, how to extract the trinitrogen from the B explosive In the fourth example, the explosive is first melted from the elastomer by subjecting the shell to carbon dioxide treatment at a temperature of 85 ° C (81 ° C above the melting point of the explosive), followed by extraction to increase efficiency. In these examples, trinitrotoluene is melted from the elastomer by carbon dioxide treatment at a temperature higher than the melting point of trinitrotoluene, which is a common technique used by this person, so it is highly probable There is a risk of unexpected explosions during the operation of the melt tank.

In addition, in the first claim of the aforementioned patent, the trinitrotoluene is melted from the elastomer by the carbon dioxide treatment at a temperature higher than the melting point of the trinitrotoluene, and the trinitrotoluene is removed. When subjected to environmental influences above the melting point of trinitrotoluene, it will be melted from any of the filling envelopes, which is clearly familiar to those skilled in the art.

The melting point refers to the temperature at which the solid phase and the liquid phase of a substance reach equilibrium. Therefore, it is normal for a substance to melt in an environment higher than its melting point, but it should be particularly noted that when a substance will be low Melting at the temperature of its melting point. In short, the aforementioned patent is characterized in that the trinitrotoluene has a greater solubility than other explosives when subjected to a supercritical carbon dioxide environment, and the molten trinitrotoluene is extracted from the shell.

It is well known that many explosive components also have extremely low solubility in a supercritical fluid based on carbon dioxide. In addition, trinitrotoluene also has a very low solubility in a supercritical fluid based on carbon dioxide, and therefore, since high energy explosives The recovery of trinitrotoluene requires a large amount of supercritical fluid based on carbon dioxide, and thus has to be increased in cost. For example, Morris, the inventor of U.S. Patent No. 5,953,679, discloses that the solubility of trinitrotoluene is 16 mg/ml in supercritical carbon dioxide gas at a temperature of 65 ° C and a pressure of 27.6 MPa. In the supercritical carbon dioxide gas at a temperature of 65 ° C and a pressure of 27.6 MPa, 6,600 g of trinitrotoluene was extracted from the warhead of a 155 mm cannon, and 412.5 liters of supercritical carbon dioxide liquid was used. The extraction tank had 415 liters. Capacity and high processing costs. Alternatively, in a supercritical carbon dioxide gas at a temperature of 65 ° C and a pressure of 27.6 MPa, 6,600 grams of trinitrotoluene is extracted from the warhead of a 155 mm cannon, and it takes 190 days to flow at a flow rate of 1.5 ml per minute. . Therefore, how to use the supercritical carbon dioxide fluid to recover trinitrotoluene from high-energy explosives is an extremely problem to be solved in the field of technology.

The application of supercritical fluid technology to the traditional extraction separation step is a rapidly developed chemical separation technology in recent years. Since the critical temperature of carbon dioxide is 31 ° C, the separation procedure under supercritical conditions can be carried out under conditions close to room temperature, and the critical pressure of carbon dioxide (7.39 MPa) is moderate and at the same time non-flammable, non-toxic, and chemically stable. It is cheap, easy to obtain, and so on. It is known that supercritical carbon dioxide fluids are well suited for use in the highly hazardous explosives industry.

In view of this, the inventors have improved the process for extracting and separating the trinitrotoluene component of the supercritical carbon dioxide fluid, and providing a trinitrotoluene separation by batch using supercritical carbon dioxide fluid under low temperature conditions. Method flow, as shown in Figure 1, the separation method of the warhead de-dosing with a supercritical fluid, the method comprising: (1) placing a projectile containing explosive components into a separation tank; (2) a supercritical fluid is supplied to the separation tank; (3) after the projectile is in contact with the supercritical fluid, at a temperature lower than a melting point of the explosive component and under a separation condition of a pressure sufficient to be separated of the explosive component, The explosive component is subjected to a separation operation; (4) simultaneously performing an ultrasonic oscillation step on the separation tank to accelerate the separation of the explosive component from the projectile, the frequency of which is preset to 0.01 megahertz (MHz) - Between 10 megahertz (MHz).

The explosive component comprises one of trinitrotoluene and a trinitrotoluene-based explosive.

The explosives based on the trinitrotoluene are one selected from the group consisting of the following B explosives, Amata explosives, Okto explosives and Arsenal explosives.

The optimum ultrasonic oscillation frequency of the separation condition is 4 megabytes.

The supercritical fluid is carbon dioxide.

The separation conditions include a temperature between 50 and 75 ° C and a pressure between 15 and 40 MPa.

The optimum temperature for the separation conditions is 55 ° C and the optimum pressure is 25 MPa.

The process of separating the operations is carried out in batches to simplify the workflow.

The optimum temperature of the supercritical fluid is 55 ° C, and the optimum pressure is 25 MPa.

The technical means to which the present invention solves the problem and the efficacy against the prior art are:

The effect achieved by the present invention is as follows: it is safe because carbon dioxide as a supercritical fluid is used at a temperature lower than the melting point of trinitrotoluene; it is an environmentally friendly method because no organic solvent is used for collection purposes, Carbon dioxide can be recycled and reused after the separation process, so it does not cause pollution; it is economical, because the method saves time and is carried out in batch mode, and trinitrotoluene is separated in a molten state, resulting in trinitr The percentage of separation of toluene is increased.

In addition, an ultrasonic oscillation process is simultaneously added to accelerate the separation of the explosive from the warhead, that is, the explosive is melted only when separated from the warhead and further separated from the separation tank. Therefore, the invention has short processing time, low processing temperature and safety. High advantage.

The specific embodiments of the present invention will be further described by the following examples and the accompanying drawings.

10. . . First storage tank

11. . . Control valve

13. . . pressure gauge

20. . . filter

30. . . Second storage tank

31. . . Control valve

32. . . Temperature display device

40. . . High pressure pump

41. . . Control valve

42. . . Control valve

50. . . Separation tank

51. . . thermostat

510. . . Slot

511. . . Housing space

512. . . Note entry

513. . . exhaustion hole

514. . . Ultrasonic generator

515. . . Ultrasonic generator

52. . . Voltage controller

53. . . Current limiter

60. . . Disinfecting rack

61. . . Pharmacy body

611. . . Housing space

612. . . Injection end

613. . . Discharge end

62. . . Support frame

63. . . Hanging ring

651. . . Warhead holder

652. . . Warhead holder

66. . . Explosive collection tank

70. . . Pressure buffer

1 is a flow chart showing a method for removing a warhead by a supercritical fluid according to the present invention;
Figure 2 is a schematic view showing the apparatus required to implement the embodiment of Figure 1;
Figure 3 is a schematic view showing the separation tank in the embodiment of Figure 2.

The supercritical fluid selected for the present invention is carbon dioxide, and the temperature and pressure at the critical point are defined as the critical temperature (Tc) and the critical pressure (Pc), which are used for the critical parameter of carbon dioxide, the critical temperature is 31 ° C, and the critical pressure is 7.39 MPa. A supercritical fluid is formed when the temperature and pressure of the material are greater than their critical parameters.

To effectively separate the explosive, an ultrasonic generator 514, 515 (see Fig. 3) is attached to the separation tank 50, and the separation operation is completed at a temperature of about 55 ° C and a pressure of about 25 MPa. Since carbon dioxide is non-flammable, non-toxic, chemically stable and inexpensive, all explosive components can be separated in a safe and cost-effective manner using a carbon dioxide-based supercritical fluid.

Please refer to FIG. 1 and FIG. 2 simultaneously, which are a flow chart showing a method for removing warheads from a supercritical fluid according to the present invention and a schematic diagram of a device required to carry out the embodiment of FIG. 1.

In the first embodiment, in accordance with the method of the present invention, a method for removing a drug from a bullet by a supercritical fluid, the method comprising the steps of: (1) placing a projectile containing an explosive component into a separation tank; (2) a supercritical fluid is supplied to the separation tank; (3) after the projectile is in contact with the supercritical fluid, at a temperature lower than a melting point of the explosive component and under a separation condition of a pressure sufficient to be separated of the explosive component, The pyrotechnic composition is subjected to a separation operation; (4) an ultrasonic wave oscillating step is simultaneously performed on the separation tank to accelerate the separation of the explosive component from the projectile.

As shown in FIG. 2, during operation, carbon dioxide is stored in a first storage tank 10, and carbon dioxide is introduced into a filter 20 through a control valve 11 by a pump 12, and filtered through the filter 20. The pure carbon dioxide enters a second storage tank 30 through a control valve 31.

The carbon dioxide in the second storage tank 30 is heated to an operating temperature by a heater (not shown), and the second storage tank 30 is provided with a temperature display device 32 for measuring the temperature of the carbon dioxide contained in the tank, and the heated carbon dioxide is firstly A pump 40 is pressurized and then enters a separation tank 50 in a supercritical fluid state.

Control valves 41, 42 are respectively disposed at the front and rear ends of the pipeline of the pump 40. The arrangement of the control valves 41, 42 can adjust the amount of carbon dioxide supplied to the separation tank 50 as a supercritical fluid, and the separation tank 50 is provided with a temperature controller 51. A pressure controller 52 is provided so that the person operating the system can monitor the temperature and pressure of the carbon dioxide contained in the separation tank 50.

In the present embodiment, it is preferred that the temperature of the separation tank 50 is low enough and the medium pressure is sufficient to allow the explosive component to contact the supercritical fluid at a predetermined temperature range and a predetermined pressure range, sufficient to separate the explosive component, and then super The critical fluid can flow to a flow restrictor 53 where the flow rate is reduced.

When the pressure is reduced, the supercritical carbon dioxide fluid becomes a gas at ambient temperature, and any dissolved solutes are nucleated and collected in the carbon dioxide recovery tank 70. The expanded carbon dioxide gas flows to the next station for further processing.

As shown in FIG. 3, a schematic view of the separation groove in the embodiment of FIG. 2 is shown. The separation groove 50 includes a groove body 510 having a temperature control layer (not shown), and the groove body 510 defines an accommodation space 511, a note. The inlet 512 extends through the bottom of the tank, and a discharge port 513 extends through the top of the tank. A pair of ultrasonic generators 514, 515 are connected to the inside of the tank 510.

The detachment tank 50 is provided with a detachment frame 60. The detachment frame 60 has a medicinal body 61. The medicinal body 61 has an accommodating space 611 therein. The injection end 612 of the detachment frame body 61 communicates with the injection port 512 and is A support frame placed in the separation tank 50 is supported, and the discharge end 613 of the dispenser rack body 61 communicates with the discharge port 513 of the separation tank 50.

The medicine rack 60 further includes a bracket 62, a hanging ring 63 near the discharge port 613, and the hanging ring 63 is used to move the medicine removing frame 60, and a pair of bullet holders 651 and 652 to fix a warhead (not shown). The position, and an explosive collection tank 66, the explosive collection tank 66 is located below the bullet holders 651, 652.

During operation, along with the ultrasonic oscillation process, the explosive component contained in the projectile body can contact the supercritical carbon dioxide fluid at an optimum frequency, temperature and pressure range, and the explosive component is separated or separated and temporarily stored in the explosive collection tank 66. in.

In the present invention, the following experiment was carried out in accordance with the steps of the above-described embodiment, using the accommodating space 511 having a practical use capacity of 2 liters.

Example 1: Low Temperature Separation of Trinitrotoluene

A simulated warhead having a diameter of 40 mm and containing 60 g of trinitrotoluene is fixed to the stripping rack 60 with the opening facing downward, and the stripping rack 60 and the warhead (ie, the projectile shell) are placed together in a separating tank 50. Then, it is sealed, and when the supercritical carbon dioxide fluid is supplied to the separation tank 50, trinitrotoluene is separated from the warhead. The separation percentage of trinitrotoluene in the 30 minutes separation operation at different temperatures and pressures is as listed in Table 1 below.

Table 1

The trinitrotoluene separation rate is the weight of the separated trinitrotoluene divided by the weight of the trinitrotoluene before separation, and the percentage (%) is taken again.

Example 2: Low temperature separation of trinitrotoluene

A simulated warhead having a volume of 250 ml and containing 250 g of trinitrotoluene is fixedly attached to a stripping rack 60 with the opening facing downward, and the stripping rack 60 and the warhead are placed together in a separating tank 50 and then sealed. When supercritical carbon dioxide is supplied to the separation tank 50 maintained at a temperature of about 55 ° C and a pressure of about 25 MPa, trinitrotoluene is separated from the warhead. The separation operation took about 30 minutes, and as a result, after the separation operation, the warhead retained about 10 g of trinitrotoluene, and about 241 g of trinitrotoluene was collected in the trinitrotoluene collecting tank.

Example 3: Low temperature separation of trinitrotoluene

A simulated warhead having a volume of 350 ml of 500 g of trinitrotoluene is fixedly attached to a stripping rack 60 with the opening facing downward, and the stripping rack 60 and the warhead are placed together in a separating tank 50 and then sealed. When the critical carbon dioxide is supplied to the separation tank 50 maintained at a temperature of about 55 ° C and a pressure of about 25 MPa, trinitrotoluene is separated from the warhead. The separation operation took about 30 minutes, and as a result, after the separation operation, the warhead retained about 10 g of trinitrotoluene, and about 490 g of trinitrotoluene was collected in the trinitrotoluene collecting tank.

Example 4: Low temperature separation of trinitrotoluene

A 155mm howitzer warhead containing 6700 grams of trinitrotoluene is fixed to the stripping rack 60 with the opening facing down, and the stripping rack 60 and the warhead are placed together in a separating tank 50 and then sealed, in supercritical carbon dioxide. When the fluid is supplied to the separation tank 50 maintained at a temperature of about 55 ° C and a pressure of about 25 MPa, trinitrotoluene is separated from the warhead. The separation operation takes about 120 minutes.

Example 5: Low temperature separation of trinitrotoluene

A 155mm howitzer warhead containing 6700 grams of trinitrotoluene is fixed to the stripping rack 60 with the opening facing down, and the stripping rack 60 and the warhead are placed in a separating groove 50 and sealed, and the ultrasonic wave is started. The generator, having an oscillation frequency of between 0.01 megahertz and 10 megahertz, begins to separate the trinitrotoluene from the warhead when the supercritical carbon dioxide fluid is supplied to the separation vessel 50 maintained at a temperature of about 55 ° C and a pressure of about 25 MPa. The separation operation takes about 60 minutes.

Example 6: Ultrasonic separation of trinitrotoluene at low temperature

The simulated warhead melts a 350 ml metal container into 500 g of trinitrotoluene explosive, and the opening is fixed downward to the dispensing rack 60, and then the dispensing rack 60 and the drug-containing warhead are placed in the separation tank 50 and sealed. The ultrasonic generators 514, 515 are activated, and the oscillation frequencies are set to 0.01, 0.05, 0.1, 0.5, 1, 5, and 10 megabytes, respectively. The experiment was carried out under the optimum operating conditions of low temperature separation, and the results are shown in Table 2 below.

Table 2

Example 7: Ultrasonic separation of trinitrotoluene at low temperature

The simulated warhead melts a 350 ml metal container into 500 g of trinitrotoluene explosive, and the opening is fixed downward to the dispensing rack 60, and then the dispensing rack 60 and the drug-containing warhead are placed in the separation tank 50 and sealed. The ultrasonic generators 514, 515 are activated, and the oscillation frequencies are set to 2, 4, 6, 8, 10 mega tex, respectively. The experiment was carried out under the optimum operating conditions of low temperature separation, and the results are shown in Table 3 below.

table 3

The above is only the preferred embodiment of the present invention, and thus is not intended to limit the scope of the present invention. Therefore, the simple modifications and equivalent structural changes that are made by using the description and the drawings of the present invention should be included in the same manner. Within the scope of the patent of the present invention.

no.

Claims (13)

A method for separating a warhead with a supercritical fluid, the method comprising:
(1) placing a projectile containing explosives into a separation tank;
(2) supplying a supercritical fluid to the separation tank;
(3) after the projectile is in contact with the supercritical fluid, the separation of the explosive component is carried out at a temperature below the melting point of the explosive component and under separation conditions in which the explosive component is sufficiently separated;
(4) Simultaneously performing an ultrasonic oscillation step on the separation tank to accelerate the separation of the explosive component from the projectile body, and the ultrasonic oscillation frequency is preset to be between 0.01 megagrams and 10 mega megabytes. A method for deballing a warhead with a supercritical fluid according to the first aspect of the invention, wherein the explosive component comprises one of trinitrotoluene and a trinitrotoluene-based explosive. The method for removing warheads by supercritical fluid according to the second aspect of the patent application, wherein the explosive containing trinitrotoluene comprises B explosives, Amata explosives, Okto explosives and arsenite explosives. One of them. A method for deballing a warhead with a supercritical fluid as described in claim 3, wherein the optimum ultrasonic oscillation frequency of the separation condition is 4 megabytes. A method of debonding a warhead with a supercritical fluid as described in claim 2, wherein the supercritical fluid is carbon dioxide. A method for deballing a warhead with a supercritical fluid as described in claim 2, wherein the separation condition comprises a temperature between 50 and 75 ° C and a pressure between 15 and 40 MPa. A method for removing warheads by a supercritical fluid as described in claim 6 wherein the optimum temperature of the separation conditions is 55 ° C and the optimum pressure is 25 MPa. A method for deballing a warhead with a supercritical fluid as described in claim 1 wherein the optimum ultrasonic oscillation frequency of the separation condition is 4 megabytes. The method for removing warheads by supercritical fluid according to the first aspect of the patent application, wherein the process of the separation operation is carried out in batch mode to simplify the operation process. The method for deballing a warhead with a supercritical fluid according to the first aspect of the patent application, wherein the supercritical fluid has an optimum temperature of 55 ° C and an optimum pressure of 25 MPa. A method for deballing a warhead with a supercritical fluid as described in claim 1, wherein the supercritical fluid is carbon dioxide. A method for deballing a warhead with a supercritical fluid as described in claim 1, wherein the separation condition comprises a temperature between 50 and 75 ° C and a pressure between 15 and 40 MPa. The method for deballing a warhead with a supercritical fluid as described in claim 12, wherein the optimum temperature of the separation condition is 55 ° C and the optimum pressure is 25 MPa.