Title of Invention	"A COMPOSITION USEFUL FOR EXCAVATION WORKS SUCH AS BLASTING IN COAL/NON-COAL SURFACE MINES"
Abstract	A composition useful for excavation works such as blasting in coal / non-coal surface mines, which comprises: an oxidizing agent ammonium nitrate 73.79 to 74.67 wt%; a reducing agent(s) selected from: diesel 1.76 to 1.78 wt%; wax 2.02 to 2.04 wt%; thiourea 0.10 to 0.11 wt%; urea 2.35 to 2.37 wt%; emulsifier selected from: sorbitan mono oleate 1.58 to 1.60 wt% gassing agent(s) selected from acrylamide 0.05 to 0.08 wt%; sodium nitrate 0.05 to 0.08 wt%; and water 18.00 to 19.00 wt%.

Title of Invention

"A COMPOSITION USEFUL FOR EXCAVATION WORKS SUCH AS BLASTING IN COAL/NON-COAL SURFACE MINES"

Abstract

A composition useful for excavation works such as blasting in coal / non-coal surface mines, which comprises: an oxidizing agent ammonium nitrate 73.79 to 74.67 wt%; a reducing agent(s) selected from: diesel 1.76 to 1.78 wt%; wax 2.02 to 2.04 wt%; thiourea 0.10 to 0.11 wt%; urea 2.35 to 2.37 wt%; emulsifier selected from: sorbitan mono oleate 1.58 to 1.60 wt% gassing agent(s) selected from acrylamide 0.05 to 0.08 wt%; sodium nitrate 0.05 to 0.08 wt%; and water 18.00 to 19.00 wt%.

Full Text	This invention relates to a composition useful for excavation works such as blasting in coal / non-coal surface mines. This invention particularly relates to a formulation useful for excavation works particularly for surface coal and non-coal mines. It is a booster sensitive emulsion explosive composition. Dynamites used in the mining industries are granular dynamite and gelatin dynamite. Granular dynamite is a mixture which uses nitroglycerin (NG) as explosive, whereas gelatin dynamite uses a mixture of NG and NC which produces a rubbery water proof compound. They explosives require extra care during handling and usage in blasting operations as they are highly sensitive to shock, friction and temperature, they burn or explode or detonate when they come in contact with a flame. Ammonium nitrate and fuel oil mixture (ANFO) is used in blasting operation the world over. The efficiency of ANFO is dependent on the size of prill, normally 1 mm, and porosity. Major limitations of the use of ANFO in mines are its lack of water resistance, low density and low bulk strength. The poor water resistance and low VOD of ANFO lead to the development of slurry and emulsion explosives. Slurry explosives, more popular in India both as cap and non-cap sensitive explosives in small and large diameter cartridge. The bulk strength of slurry explosives is lower than NG based explosives. Compared to the NG based explosives slurry explosives are however, more water resistant and have less toxic fumes such as NOX and CO. Emulsion explosives, commonly water-in-oil emulsions, provide high interfacial contact between oxidizer and fuel, resulting in a high degree of sensitivity and high rate of reactivity without the use of any molecular explosive. The unique property of emulsion explosive is its high velocity of detonation (VOD) ranging from 4000 - 6000 m/s. This results in high detonation pressure and brisance effect which helps in improving rock fragmentation. The fuel phase being water immiscible, these explosives are water resistant and insensitive to impact. In surface mine blasting, two types of explosives mainly are used, one is cap sensitive (prime charge) and another is non-cap sensitive (column charge). The ratio of the both cap and non-cap sensitive explosives should be always 1:4. Therefore, non-cap sensitive explosive is major product in blasting works. The main drawback of non-cap sensitive emulsion explosives are poor shelf life causing loosening of the cartridge, breaking of the emulsion lattice and increasing of density resulting in , misfires. Therefore, there is a requirement of a stable, having good shelf life, cheaper and safe non-cap sensitive emulsion explosive suitable for rock blasting. The main objective of present invention is to provide a composition useful for excavation works such as blasting in coal / non-coal surface mines which obviate the above noted drawbacks. Another object is to provide an explosive composition which would be non-cap sensitive emulsion explosive for blasting in surface mines. Yet another object of the present invention is to provide a composition consisting of ingredients such as oxidizing and reducing agents, emulsifiers, gassing agents to produce zero oxygen balance and suitable as a column non-cap sensitive emulsion explosive. The composition of the present invention may be prepared as follows: The oxidizing agent such a ammonium nitrate is dissolved in water at 67° - 70°C in a container. Fuel such as thiourea and urea are added to the said container and mixed well with the help of a stirrer. Wax, Diesel and sorbitan mono oleate are mixed well in an other container and maintained at a temperature of 60° to 70°C . Solution of first container is slowly mixed to contents in second container and mixed keeping the speed of stirrer above 3000 RPM. As the emulsion formation starts, speed of the stirrer is increased & maintained at 5000 RPM. And lastly, acrylamide and sodium nitrite are added as gassing agents. The product obtained has zero oxygen balance in emulsion form. Accordingly the present invention provides, a A composition useful for excavation works such as blasting in coal / non-coal surface mines, which comprises: an oxidizing agent ammonium nitrate 73.79 to 74.67 wt%; a reducing agent(s) selected from: diesel 1.76 to 1.78 wt%; wax 2.02 to 2.04 wt%; thiourea 0.10 to 0.11 wt%; urea 2.35 to 2.37 wt%; emulsifier selected from: sorbitan mono oleate 1.58 to 1.60 wt% , gassing agent(s) selected from acrylamide 0.05 to 0.08 wt%; sodium nitrate 0.05 to 0.08 wt%; and water 18.00 to 19.00 wt%. The reducing agent used may be such as diesel, wax, thiourea, urea or mixture thereof. The gassing agent used may be such as acrylamide, sodium nitrate or mixture thereof. The oxidizing and reducing agents used may be of 99% purity. The emulsifier used may be of 98% purity. The gassing agents used may be of 99% purity.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. Explosive properties of the composition of the present invention are given below in Table -1 (Table Removed) We Claim: 1. A composition useful for excavation works such as blasting in coal / non-coal surface mines, which comprises: an oxidizing agent ammonium nitrate 73.79 to 74.67 wt%; a reducing agent(s) selected from: diesel 1.76 to 1.78 wt%; wax 2.02 to 2.04 wt%; thiourea 0.10 to 0.11 wt%; urea 2.35 to 2.37 wt%; emulsifier selected from: sorbitan mono oleate 1.58 to 1.60 wt% , gassing agent(s) selected from acrylamide 0.05 to 0.08 wt%; sodium nitrate 0.05 to 0.08 wt%; and water 18.00 to 19.00 wt%. 2. A composition as claimed in claim 1 wherein the reducing agent used is selected from diesel, wax, urea, thiourea or mixture thereof. 3. A composition as claimed in claims 1 & 2 wherein the gassing agent used is selected from acrylamide, sodium nitrate or mixture thereof. 4. A composition useful or excavation works such as blasting in coal / non - coal surface mines substantially as herein described.

Full Text

This invention relates to a composition useful for excavation works such as blasting in coal / non-coal surface mines.
This invention particularly relates to a formulation useful for excavation works particularly for surface coal and non-coal mines. It is a booster sensitive emulsion explosive composition.
Dynamites used in the mining industries are granular dynamite and gelatin dynamite. Granular dynamite is a mixture which uses nitroglycerin (NG) as explosive, whereas gelatin dynamite uses a mixture of NG and NC which produces a rubbery water proof compound. They explosives require extra care during handling and usage in blasting operations as they are highly sensitive to shock, friction and temperature, they burn or explode or detonate when they come in contact with a flame.
Ammonium nitrate and fuel oil mixture (ANFO) is used in blasting operation the world over. The efficiency of ANFO is dependent on the size of prill, normally 1 mm, and porosity. Major limitations of the use of ANFO in mines are its lack of water resistance, low density and low bulk strength. The poor water resistance and low VOD of ANFO lead to the development of slurry and emulsion explosives.
Slurry explosives, more popular in India both as cap and non-cap sensitive explosives in small and large diameter cartridge. The bulk strength of slurry explosives is lower than NG based explosives. Compared to the
NG based explosives slurry explosives are however, more water resistant and have less toxic fumes such as NOX and CO.
Emulsion explosives, commonly water-in-oil emulsions, provide high interfacial contact between oxidizer and fuel, resulting in a high degree of sensitivity and high rate of reactivity without the use of any molecular explosive.
The unique property of emulsion explosive is its high velocity of detonation (VOD) ranging from 4000 - 6000 m/s. This results in high detonation pressure and brisance effect which helps in improving rock fragmentation. The fuel phase being water immiscible, these explosives are water resistant and insensitive to impact.
In surface mine blasting, two types of explosives mainly are used, one is cap sensitive (prime charge) and another is non-cap sensitive (column charge). The ratio of the both cap and non-cap sensitive explosives should be always 1:4. Therefore, non-cap sensitive explosive is major product in blasting works. The main drawback of non-cap sensitive emulsion explosives are poor shelf life causing loosening of the cartridge, breaking of the emulsion lattice and increasing of density resulting in , misfires. Therefore, there is a requirement of a stable, having good shelf life, cheaper and safe non-cap sensitive emulsion explosive suitable for rock blasting.
The main objective of present invention is to provide a composition useful for excavation works such as blasting in coal / non-coal surface mines which obviate the above noted drawbacks.

Another object is to provide an explosive composition which would be non-cap sensitive emulsion explosive for blasting in surface mines.
Yet another object of the present invention is to provide a composition consisting of ingredients such as oxidizing and reducing agents, emulsifiers, gassing agents to produce zero oxygen balance and suitable as a column non-cap sensitive emulsion explosive.
The composition of the present invention may be prepared as follows: The oxidizing agent such a ammonium nitrate is dissolved in water at 67° - 70°C in a container. Fuel such as thiourea and urea are added to the said container and mixed well with the help of a stirrer. Wax, Diesel and sorbitan mono oleate are mixed well in an other container and maintained at a temperature of 60° to 70°C . Solution of first container is slowly mixed to contents in second container and mixed keeping the speed of stirrer above 3000 RPM. As the emulsion formation starts, speed of the stirrer is increased & maintained at 5000 RPM. And lastly, acrylamide and sodium nitrite are added as gassing agents. The product obtained has zero oxygen balance in emulsion form.
Accordingly the present invention provides, a A composition useful for excavation works such as blasting in coal / non-coal surface mines, which comprises: an oxidizing agent ammonium nitrate 73.79 to 74.67 wt%; a reducing agent(s) selected from: diesel 1.76 to 1.78 wt%; wax 2.02 to 2.04 wt%; thiourea 0.10 to 0.11 wt%; urea 2.35 to 2.37 wt%; emulsifier selected from: sorbitan mono oleate 1.58 to 1.60 wt% , gassing agent(s) selected from acrylamide 0.05 to 0.08 wt%; sodium nitrate 0.05 to 0.08 wt%; and water 18.00 to 19.00 wt%.
The reducing agent used may be such as diesel, wax, thiourea, urea or mixture thereof. The gassing agent used may be such as acrylamide, sodium nitrate or mixture thereof. The oxidizing and reducing agents used may be of 99% purity. The emulsifier used may be of 98% purity. The gassing agents used may be of 99% purity.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. Explosive properties of the composition of the present invention are given below in Table -1
(Table Removed)

We Claim:
1. A composition useful for excavation works such as blasting in coal / non-coal
surface mines, which comprises: an oxidizing agent ammonium nitrate 73.79 to 74.67 wt%; a reducing agent(s) selected from: diesel 1.76 to 1.78 wt%; wax 2.02 to 2.04 wt%; thiourea 0.10 to 0.11 wt%; urea 2.35 to 2.37 wt%; emulsifier selected from: sorbitan mono oleate 1.58 to 1.60 wt% , gassing agent(s) selected from acrylamide 0.05 to 0.08 wt%; sodium nitrate 0.05 to 0.08 wt%; and water 18.00 to 19.00 wt%.
2. A composition as claimed in claim 1 wherein the reducing agent used is selected
from diesel, wax, urea, thiourea or mixture thereof.
3. A composition as claimed in claims 1 & 2 wherein the gassing agent used is
selected from acrylamide, sodium nitrate or mixture thereof.
4. A composition useful or excavation works such as blasting in coal / non - coal
surface mines substantially as herein described.

Documents:

3836-del-1998-abstract.pdf

3836-del-1998-claims.pdf

3836-del-1998-correspondence-others.pdf

3836-del-1998-correspondence-po.pdf

3836-del-1998-description (complete).pdf

3836-del-1998-form-1.pdf

3836-del-1998-form-19.pdf

3836-del-1998-form-2.pdf

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Patent Number

215672

Indian Patent Application Number

3836/DEL/1998

PG Journal Number

12/2008

Publication Date

21-Mar-2008

Grant Date

29-Feb-2008

Date of Filing

24-Dec-1998

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH

Applicant Address

RAFI MARG, NEW DELHI-110001

Inventors:

#	Inventor's Name	Inventor's Address
1	JAGDISH	CENTRAL MINING RESERCH INSTITUTE, BARWA ROAD, DHNBAD -826001, INDIA,
2	NABIULLAH	CENTRAL MINING RESERCH INSTITUTE, BARWA ROAD, DHNBAD -826001, INDIA,
3	BRAJ MOHAN PAT PINGUA,	CENTRAL MINING RESERCH INSTITUTE, BARWA ROAD, DHNBAD -826001, INDIA,
4	TRIBHUWAN NATH SINGH	CENTRAL MINING RESERCH INSTITUTE, BARWA ROAD, DHNBAD -826001, INDIA,

PCT International Classification Number

F42D 1/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA