Title of Invention

"A COMPOSITION USEFUL FOR SAFE BLASTING OF COAL IN UNDERGROUND MINES AND OTHER EXCAVATION WORK AND A PROCESS FOR PREPARING THE SAID COMPOSITION"

Abstract Title: A composition useful for safe blasting of coal in underground mines and other excavation works A composition useful for safe blasting of coal in underground mines and other excavation works, which comprises: Oxidizing agent (s) (a) Ammonium nitrate 40.15 to 41.10wt% (b) Calcium nitrate 13.50 to 14.00 wt% Reducing agent (s): (a) Aluminum powder 2.50  to 3.00 wt% (b) Sugar 7.34  to 7.40 wt% (C)Thiourea 0.10  to 0.09 wt% (d)Urea 1.80  to 2.36 wt% (e) Guar gum 0.9 to    1.0 wt% Cooling agent(s): (a) Water 18.45 to 19.00 wt% (b) Sodium chloride 14.01 to 14.50 wt% Cross-linking agent(s)              0.04 to   0.05 wt% Gassing agent(s) 0.04  to 0.05. wt% Stabilizer 0.09  to 0.10 wt%
Full Text This invention relates to a composition useful for safe blasting of coal in underground mines and other excavation works and a process for preparing the said composition.
The nitroglycerine (NG) based explosives are available in cartridge form in diameter 32 mm and weight 200 gm. These explosives have velocity of detonation (VOD) ranging from 2000 to 2500 m/sec. and strength from 35 to 40 percent blasting gelatin explosive. The density varies from 1.00 to 1.20 gm/cm3. Its cartridge material is waxed paper. These are highly sensitive to shock, friction, heat and flame. The fume quality is poor. When misfired, explosives are mixed in blasted muck may cause accident during loading and thereby increased danger during the operation.
The shiny explosives contained oxidizing agents in the range of 50 - 70 wt%, reducing agents in the range of 10 - 20 wt%, cooling agents in the range of 5 - 20 wt % and rest in the range of 0.1 - 1 wt % . Slurry explosives are available in cartridge form having a diameter from 32 mm , weight 200 gm. and cartridge material is plastic tube with copper clips or blow molded tube. They are cap sensitive composition. Their velocity of detonation varies from 2900 to 3300 m/sec. and density 1.10 to 1.15 gm/cm3.
Emulsion explosives have high velocity of detonation ranging from 3500 to 4000 m/sec. They are available in 32 mm diameter and suitable for only zero degree gassy coal mines.
The main objective of the present invention is to provide a composition useful for excavation works for safe blasting of coal in underground mines which obviates the above noted drawbacks.
Another object is to provide an explosive composition for blasting of coal from underground gassy and dusty coal mines.
Yet another object is to develop an explosive composition which would be permitted for solid blasting of coal (P5) underground mines. The P5 group ( P3 explosive formulation are used in solid blasting of coal) of explosive for blasting of coal in 32 mm

Diameter and cap - sensitive, low velocity of detonation (less than 3300 m/sec.) and non-incendive in methane and coal dust explosive mixture.
The composition of the present invention utilizes ingredients of oxidizing, reducing, crossi-linking, gassing agents and stabilizer to produce zero oxygen balance to provide a composition suitable as a slurry explosive.
Accordingly, the present invention provides a composition useful for safe blasting of coal in underground mines and other excavation works, which comprises: Oxidizing agent (s)
(a) Ammonium nitrate 40.15 to 41.10wt%
(b) Calcium nitrate 13.50 to 14.00wt%
Reducing agent (s):

(a) Aluminum powder 2.50 to 3.00wt%
(b) Sugar 7.34 to 7.40 wt%
(C)Thiourea 0.10 to 0.09 wt%
(d)Urea 1.80 to 2.36 wt%
(e)Guargum 0.9 to 1.0 wt%
Cooling agent(s):
(a) Water 18.45 to 19.00 wt%
(b) Sodium chloride 14.01 to 14.50 wt%
Cross-linking agents) 0.04 to 0.05 wt%
Gassing agent(s) 0.04 to 0.05 wt%
Stabilizer 0.09 to 0.10wt%
The oxidizing agent used may be such as ammonium nitrate, calcium nitrate or mixture thereof.
The reducing agent used may be such as aluminium powder (flake), sugar, thiourea, urea, guar gum, mono-ethylene glycol or mixture thereof.
The cooling agent used may be such as sodium chloride, water or mixture thereof.
The crosslinking agent used may be such as potassium pyroantimonate, potassium antimony tartarate.
The gassing agent used may be such as sodium nitrite, Potassium thiocynate or mixture thereof.
The stabilizer used may be such as thiourea.
The oxidizing and reducing agents used may be of 99% purity.
The cross-Unking agents used may be of 95 % purity.
The gassing agents used may be of 99 % purity.
In an embodiment of the present invention, the composition may consist of:
Ammonium nitrate 40.15 to 41.10 wt%
Calcium nitrate 13.50 to 14.00 wt%
Aluminium Powder 2.50 to 3.00 wt%
Sugar 7.34 to 7.40 wt%

Urea 1.80 to 2.36 wt%
Guar gum 0.9 to 1.00 wt%
Sodium chloride 14.01 to 14.50 wt%
Water 18.45 to 19.00 wt%
Potassium pyro antimonate 0.04 to 0.05 wt%
Sodium nitrite 0.04 to 0.05 wt%
It is a feature of the present invention that the composition is not a mere admixture
but a synergistic mixture having properties which are different to the mere aggregation of
the properties of the individual ingredients.
Accordingly the present invention provides a process for preparing the composition of the present invention, which comprizes dissolving oxidizing agents in water at 65 -70 °C and maintaining pH of the solution in the range 4.5 to 5.0 by adding acetic acid / nitric acid, adding to the solution so obtained fuel such as thiourea, urea, sugar and guar gum and mono ethylene glycol and cooling agent such as chloride.
The product is zero oxygen balanced in the slurry form. The composition is sensitized by using aluminium powder (Flake grade) followed by treatment with gassing and cross-linking agents.
The composition prepared is sensitized enough to be initiated for copper detonator (No.6) consisting of lead azide, lead styphante, aluminium (ASA) 0.20 gm and pentaerythritol tetranitrate (PETN) 0.22 gm.
The following examples are given by way of illustration and should not be construed to limit the scope of the present invention.
Example 1.

(Table Removed)
The oxidizing agents such as ammonium nitrate and calcium nitrate is dissolved in required quantity of water at 65 ± 5 ° C. The pH of the solution is maintained by adding dilute nitric acid at 4.50 to 5.0. The required fuels such as thiourea, urea, sugar and guar gum were added to oxidizing solution.
The product is zero oxygen balanced in the slurry form. The composition is sensitized by using aluminium powder (Flake grade) followed by treatment with gassing and cross-linking agents.
Explosive properties of example 1.

(Table Removed)
Example 2.

(Table Removed)
The oxidizing agents such as ammonium nitrate and calcium nitrate is dissolved in required quantity of water at 65 ± 5 ° C. The pH of the solution is maintained by adding dilute nitric acid/ acetic acid at 4.50 to 5.0. The required fuels such as thiourea, urea, sugar and guar were added to oxidizing solution.
The product is zero oxygen balanced in the slurry form. The composition is sensitized by using aluminium powder (Flake grade) followed by treatment with gassing and cross-linking agents.
Explosive Properties of example 2

(Table Removed)
The characteristic explosive properties of the above composition is given below:

(Table Removed)
The main advantage of the explosive composition of the present invention are:
1. It is a cap sensitive composition.
2. The composition would be useful for solid blasting of coal in underground mines.



We Claim:
1. A composition useful for safe blasting of coal in underground mines and other
excavation works, which comprises:
Oxidizing agent (s)
(a) Ammonium nitrate 40.15 to 41.10wt%
(b) Calcium nitrate 13.50 to 14.00 wt%
Reducing agent (s):

(a) Aluminum powder 2.50 to 3.00wt%
(b) Sugar 7.34 to 7.40 wt%
(C)Thiourea 0.10 to 0.09 wt%
(d)Urea 1.80 to 2.36 wt%
(e)Guargum 0.9 to 1.0 wt%
Cooling agent(s) :
(a) Water 18.45 to 19.00 wt%
(b) Sodium chloride 14.01 to 14.50 wt%
Cross-linking agents) 0.04 to 0.05 wt%
Gassing agent(s) 0.04 to 0.05 wt%
Stabilizer 0.09 to 0.10wt%
2. A composition as claimed in claim 1 wherein the cross-linking agent used is such
as potassium pyroantimonate, potassium antimony tartarate or mixture thereof.
3. A composition as claimed in claims 1-2 wherein the gassing agent used is such as
sodium nitrite, Potassium thiocyanate or mixture thereof.
4. A composition as claimed in claims 1-3 wherein the stabilizer used is such as
thiourea
5. A composition as claimed in claims 1-4 wherein the oxidizing and reducing agents
used is of 99% purity.
6. A composition as claimed in claims 1-5 wherein the cross-linking agents used is of
95% purity.
7. A composition as claimed in claims 1-6 wherein the gassing agents used is of 99%
purity.
8. A process for preparing the composition as claimed in claim 1, which comprises,
dissolving oxidizing agents in an amount such as herein described, in water at 65-
70°C and maintaining pH of the solution in the range of 4.5 to 5.0 by adding acetic
acid/nitric acid, adding to the solution so obtained fuel such as thiourea, urea, sugar and guar gum and monoethylene glycol and cooling agent such as sodium chloride to get the composition as described in claim 1 . 9. A composition useful for safe blasting of coal in underground mines and other
excavation works substantially as herein described with reference to the examples.

Documents:

3071-del-1998-abstract.pdf

3071-del-1998-claims.pdf

3071-del-1998-correspondence-others.pdf

3071-del-1998-correspondence-po.pdf

3071-del-1998-description (complete).pdf

3071-del-1998-form-1.pdf

3071-del-1998-form-19.pdf

3071-del-1998-form-2.pdf


Patent Number 215022
Indian Patent Application Number 3071/DEL/1998
PG Journal Number 10/2008
Publication Date 07-Mar-2008
Grant Date 20-Feb-2008
Date of Filing 20-Oct-1998
Name of Patentee COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH
Applicant Address RAFI MARG, NEW DELHI- 110 001, INDIA
Inventors:
# Inventor's Name Inventor's Address
1 NABIULLAH CENTRAL MINING RESEARCH INSTITUTE, BARWA ROAD, DHANBAD, INDIA
2 JAGDISH CENTRAL MINING RESEARCH INSTITUTE, BARWA ROAD, DHANBAD, INDIA
3 TRIBHUWAN NATH SINGH CENTRAL MINING RESEARCH INSTITUTE, BARWA ROAD, DHANBAD, INDIA
4 BRAJ MOHAN PAT PINGUA CENTRAL MINING RESEARCH INSTITUTE, BARWA ROAD, DHANBAD, INDIA
PCT International Classification Number C06B
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA