FR2460903A1 - PROCESS FOR PRODUCING NITROGLYCERIN EXPLOSIVES - Google Patents

Abstract

PROCESS FOR PRODUCING NITROGLYCERINE EXPLOSIVES BY MIXING NITROGLYCERINE AND OR NITROGLYCOL WITH PREFERRED NITROCELLULOSE AT A TEMPERATURE OF 20C; MIX SO THAT THE SURFACE OF THE MIXTURE IS FIVE TIMES GREATER THAN THE INITIAL SURFACE; THE MIXTURE IS GELIFIED TO OBTAIN A SEMI-LIQUID COMPOUND WHICH IS MIXED WITH THE REMAINING COMPONENTS OF THE EXPLOSIVE; THE WHOLE IS BREWED UNTIL A HOMOGENEOUS MIXTURE IS OBTAINED, WHICH IS PLACED IN CARTRIDGES.

Description

Process for the production of nitroQlv explosives

  The invention relates to a process for producing nitroglycerin explosives useful for

crush the rocks and not likely to cause ex-

  plosions of dust and methane. The invention is suitable for the production of explosives, in particular those whose content of liquid explosive substances is greater than

% in weight.

  A pipeline known for producing nitro-

  glycerin is the following, liquid explosives are mixed with caution, i.e. trinitroglycerin and / or

  nitroglycol and nitrocellulose and then we mix

  generously. When the gel becomes rigid, the absorbent components are added and mixed. We introduce the material

  mixed in paper or plastic cartridges

tick.

One drawback of the nitroglycerin explosives which is thus prepared is the variation in their firing properties during storage. This variation constitutes

  a significant drawback and it manifests itself primarily-

ment by a considerable decrease in the transmission of

detonation and sensitivity.

The decrease in sensitivity or initiation is often so great that you cannot initiate with a detonator. Therefore, after storage too

prolonged, the material is no longer usable and must be removed.

trout. The nitroglycerin explosives produced according to the known process have a maximum storage time of

three months.

Another disadvantage of the explosives produced according to the known method is the exudation of nitroglycerin and / or

nitroglycol during storage. The freshly pre-

  adorned with nitroglycerin and / or nitroglycol and nitro-

  cellulose is rigid. The stiffness of the gel is explained by the ac-

mechanical activity of incomplete nitrocellulose fibers-

  dissolved in the gel. Over time, as a result of the dissolving effect of nitroglycerin and / or nitroglycol, these fibers are softened, their rigidity

decreases and also their absorption capacity of nitro-

cellulose and / or nitroglycol decreases. If such a gel is subjected to the effect of a pressure or a change in temperature, the particles of nitroglycerin and / or of nitroglycol are isolated from the gel which constitutes the exudation of nitroglycerin. The essence of the invention lies in the use

  1o in the process for the preparation of nitroglycosil explosives

  rine, from the unexpected discovery that the tendency to

  air dissolution in nitroglycerin decreases rapidly-

  at temperatures above 200C. To take advantage of this effect, one must perform the operation of dissolving nitrocellulose in nitroglycerin, which is called

gelation, at a temperature below 200C,

  rant simultaneously during gelling, an increase

sufficient surface area of nitroglycerin and a

  constant contact of the increased surface and air.

  Instead of nitroglycerin, nitroglycol can be used

  or preferably mixtures of nitroglycerin and nitro-

  glycol. If nitroglycol is used, the temperature

The temperature below which the tendency for air dissolution in nitroglycol decreases rapidly drops to 15oC. For mixtures in a ratio of nitroglycerin to nitroglycol of 1/1 or more, this temperature is also in practice equal to 200C. Oxygen increases the chemical capacity of nitrocellulose to absorb nitroglycerin and / or nitroglycol, provides the gel with higher osmotic pressure and increases the ability of nitrocellulose to

absorb nitroglycerin and / or nitroglycol. Simultaneous-

  oxygen increases the tendency for the nitroglycerin and / or nitroglycol to dissolve in the nitrocellulose fibers, so that in the gelation process,

  there is no stage of formation of a rigid gel transi-

roof. The gel thus prepared of nitroglycerin is mixed

  and / or nitroglycol and nitrocellulose with the compounds

sants remaining from the explosive, it is stirred and introduced into paper or plastic cartridges at a temperature below 200C. The explosive put in cartridge, preferably in shipping packaging, is subjected to maturation at a temperature above 200C for a period of at least 7 days.

  As a result of the mixing of the gelled mixture of nitro-

  glycerin and / or nitroglycol and nitrocellulose formed beforehand, the granular component of the explosive is covered with a thin layer. During maturation at a temperature above 200C, the gelling of this mixture increases on the granular components of the explosive if

  although microsco- air bubbles form simultaneously

  spikes which due to the high viscosity of the gel in the course of evolution, do not migrate to the surface of the layer, but

form a separate phase in this gel.

  According to the method of the invention,

as follows: carefully mix nitro-

glycerin and / or nitroglycol and nitrocellulose and the mixture is stirred carefully at a temperature below 200C so that the surface of the nitroglycerin and / or nitroglycol in contact with the air is at least five times

  larger than the area of nitroglycerin and / or nitro-

  glycol at rest before brewing begins. The remaining components of the explosive are added to the mixture thus prepared and stirred. The material obtained is introduced into paper or plastic cartridges, placed in packaging and cardboard and maturation is carried out at a temperature above 200C for a period of at least

less 7 days.

  The explosive retains its practical shooting properties.

unchanged for at least a year

and half.

According to another method of the invention, the procedure is as follows: carefully mix nitroglycerin and / or nitroglycol and nitrocellulose and mix thoroughly so that the surface of the nitroglycerin and / or nitroglycol in contact with air is at least five times greater than the area of nitroglycerin and / or nitroglycol at rest before the start of brewing. Add the remaining components of the mixture and stir. The material obtained is placed in paper or plastic cartridges at the latest eight hours after mixing the explosive and the cartridges are placed in

packaging or cartons.

Nitroglycerin and / or nitroglycol are powerful explosives sensitive to mechanical shock and very dangerous during mixing. Preferably, the nitroglycerin and / or the nitroglycol are mixed with the nitrocellulose to ensure at least a fivefold increase in the surface area of the liquid to be mixed, mechanically, without human participation, in the following manner: the nitrocellulose and the nitroglycerine are introduced. and / or nitroglycol in a mixer

having the shape of a horizontal trough with a hemicylin bottom

  drique. An agitator is placed in the trough consisting of a horizontal shaft carrying a series of equidistant flat discs

  The axis of the tree coincides with the axis of the bottom of the trough. The agi-

  The operator is mechanically driven and started up at a safe distance. During the rotation of the shaft, the discs drive the components to be brewed and lifts them and in the next phase of rotation, the mixed components flow in a thin layer on the discs with their entire surface in contact with air . To improve the efficiency of stirring and increasing the surface, it is possible to use flat rings mounted on the shaft by flat arms, the plane of the rings being perpendicular

to the axis of the tree.

  The following nonlimiting examples illustrate

the method of the invention.

EXAMPLE 1 -

In a horizontal tank with a hemicylin bottom

  drique, we introduce 23 kg. a mixture of nitroglycerin and

  of nitroglycol in the ratio of 1/1 and 0.8 kg of nitrocellu-

  lose. Then introduced into the tank an agitator consisting of a horizontal shaft on which is fixedly mounted a series of flat arms. The distance between the rings and the bottom is 2 cm and their angle of inclination relative to

to the tree of 700. The distance between the rings is 5 cm.

  The agitator is rotated around its axis for 15 minutes.

  at a speed of 15 rpm. The mixing is carried out at 150C.

Two samples of 100 q each of the dense liquid obtained are collected. The first sample is subjected to additional gelation at 150C for 20 days. The second sample is subjected to additional gelation for a period of 20 days at 400C. After this period, the two samples are in the form of an elastic gel, the gel obtained at the temperature of 150C having a density of 1.478

  g / cm3 and that obtained at the temperature of 400C a density

  mique of 1,220 q / cm. The section of these gels presents

  barely visible pores under the microscope.

  Then remove the stirrer and place the thick liquid in a round basin, add the components

  remaining explosives, i.e. 69.2 kg of amnitrate

monnium, 6 kg of dinitrotoluene and 1 kg of wood flour, and the load is mixed using two vertical agitators for 12 minutes. The material thus obtained, which has a plastic and soft consistency, is placed in paper cartridges having a diameter of 32 mm in portions of 150 g. The firing properties of the material, 5 hours after putting into cartridges are as follows: increase in volume in the lead block test: 320 ml, detonation speed

  2800 m / s, transmission of the detonation: 3 cm, relative force

  Explosion rate: 70%, initiation: detonator No. 2. The firing properties after 15 days of storage at 300C and 65% relative humidity are as follows: increase in volume in the lead block test: 370 at a speed of 3 (detonation: 3400 m / s, transmission of the detonation: 6 cm, relative explosion force: 80%, initiation: detonator

# 1, no exudation noted.

The above material after 15 months of storage

  tion in a room at 230C and 80% relative humidity pre-

feels the following firing properties: increase in volume in the lead block test: 350 ml, detonation speed: 3,200 m / s, transmission of the detonation

9 cm, relative explosion force: 80% initiation: detonating-

  level 1, no exudation noted, freezing and thawing test: satisfactory

EXAMPLE 2

  In a horizontal tank with a hemicylin bottom

drique is introduced: 23 kg of a mixture of nitroglycerin and nitroglycol in the weight proportion of 1/1 and 0.8 kg

  nitrocellulose: an agri-

  tator consisting of a horizontal shaft on which is mounted a series of fixed flat arms, the distance between the rings and the back wall is 2 cm and the angle of inclination of the rings on the tree is 700. The distance between the rings is 5 cm. We rotate the agitator around its axis

  for 15 minutes at a speed of 15 rpm.

  Then remove the agitator, place the liquid

thick in a round basin, add the remaining components

explosives, i.e. 69.2 kg of ammonium nitrate

  nium, 6 kg of nitrotoluene and 1 kg of wood flour and the load is mixed with two vertical agitators for 12 minutes. We place the material obtained which has a consistency

  plastic and soft in paper cartridges having a diameter

  meter of 32 mm in portions of 150 gr. The firing properties of the material on the third day after cartridge filling are as follows: increase in volume in the lead block test: 360 ml, detonation speed 3,200 m / s, transmission of the detonation 7 cm, relative explosion explosion force: 80%, initiation: detonator no 1, no exudation noted. This material after 9 months of storage in a room at 230C and 80% relative humidity has the following shooting properties increased volume in the lead block test 355 ml, detonation rate

  3 120 m / s, transmission of the detonation: 6 cm, relative force

tive of explosion: 78%, initiation: detonator # 1, no exudation noted. Freezing and thawing test

satisfactory.

EXAMPLE 3

An explosive is prepared as in Example 1

with the exception of the composition which is as follows: nitro-

glycerin and nitroglycol in the proportion of 1/1: 45 kg,

  nitrocellulose 2 kg, ammonium nitrate: 49 kg, dinitFo-

  toluene: 2 kg, wood flour: 2 kg. The firing properties on the third day after putting in cartridges are as follows: increase in volume in the lead block test: 428 ml, detonation speed: 6,200 m / s, detonation transmission: 11 cm , relative explosion force: 95%, initiation: detonator # 1, no exudation noted. The properties of shooting

  after 20 months of storage in a room at 250C and 70 hours

  relative miditd are: volume increase

  in the lead block test: 450 ml, detonation speed

  tion: 6000 m / s, detonation transmission: 8 cm, relative explosion force 95%, initiation: detonator no 1, no exudation, noted. Satisfactory freezing and thawing test.

Claims (4)

1 - Process for producing nitro- explosives   glycerin consisting in preparing a compound for nitroglycerin and / or nitroglycol and nitrocellulose, add to this the remaining components of the explosive,   mix and place in paper or material cartridges   re plastic, characterized in that the surface of the nitro- glycerin and / or nitroglycol when mixed with nitro-   cellulose is at least five times greater than the area of nitroglycerin and / or nitroglycol before mixing begins, gelling of nitroglycerin is carried out   and / or nitroglycol until a semi-compound is obtained   liquid, this compound then being mixed with the components remaining explosive and stirred until a met   homogeneous diaper and in that we put this mixture in cartridges less than eight hours after its production.   2 - Process according to claim 1, characterized in that the gelling of the nitroglycerin and / or of the nitroglycol is carried out at a temperature below 200C until a semi-liquid compound is obtained which is then mixed with the remaining components of the explosive and stirred until a homogeneous mixture is obtained and this mixture is placed in cartridges and subjected to maturation at a temperature above 200C for a period of at least - less 7 days.   3 - Process according to claim 1, characterized in that the nitroglycerin and / or the nitroglycol is mixed with the nitrocellulose in a horizontal mixer having a semi-cylindrical bottom, that the stirring elements rotate according to   the axis of symmetry of the bottom by driving the components to   changing and lifting them so that, in the next phase of rotation, the mixed components flow in a thin layer over the elements of the agitator to return to the bottom of the mixer. 4 - Process according to claim 2, characterized in that the nitroglycerin and / or the nitroglycol is mixed with the nitrocellulose in a horizontal mixer having a semi-cylindrical bottom, that stirring elements rotate along the axis of symmetry of the bottom in driving the components to be mixed and lifting them so that in the next phase of rotation, the mixed components flow in a thin layer over the elements of the agitator to return to the bottom of the mixer.