Explosive composition containing biopolymeric material, method of preparing and using

Claim 2

AN AQUEOUS, PUMPABLE WATER-RESISTANT SLURRY EXPLOSIVE COMPOSITION SUITABLE FOR USE IN WET BOREHOLES, SAID COMPOSITION CONSISTING ESSENTIALLY OF AT LEAST ONE OXYGEN RELEASING SALT; WATER; AT LEAST ONE FUEL; FINELY DIVIDED ALUMINUM PASSING A 300 MESH SIEVE AS SENSITIZING ADDITIVE AND BIOPOLYMERIC MATERIAL PREPARED FROM A CARBOHYDRATE WHICH HAS BEEN REACTED WITH A MICROORGANISM OF THE GENUS XANTHOMONA, THE COMPOSITION BEING FREE OF ANY MATERIAL CAPABLE OF CROSSLINKING THE BIOPOLYMERIC MATERIAL.

Claim 3

A composition of matter according to claim 1 wherein the biopolymeric material comprises matter prepared from a carbohydrate which has been reacted with a microorganism of the species Xanthomonas compestris.

Claim 4

A composition of matter according to claim 1 wherein the biopolymeric material constitutes from 0.1% w/w to 5% w/w of the total composition.

Claim 5

A slurry explosive composition according to claim 1 wherein the oxygen releasing salt is selected from the group consisting of ammonium nitrate, chlorate and perchlorate, alkali metal nitrates, chlorates and perchlorates, and alkaline earth metal nitrates, chlorates and perchlorates present in an amount from 50 to 90 parts; water is present in an amount from 5 to 35 parts; the fuel material is selected from the group consisting of water soluble fuel present in an amount from 0.8 to 8 parts, non-metallic sparingly water soluble fuel and non-metallic water insoluble fuel present in an amount from 1 to 10 parts and metallic water insoluble fuel present in an amount from 0.5 to 20 parts; and the biopolymeric material is present in an amount from 0.1 to 5 parts all amounts being in parts by weight per 100 parts by weight of the composition.

Claim 6

A composition of matter according to claim 4 wherein the oxygen releasing salt is selected from the group consisting of the nitrates of the alkali metals and ammonium.

Claim 7

A composition of matter according to claim 4 wherein the oxygen releasing salt constitutes from 65% w/w to 85% w/w of the total composition.

Claim 8

A composition of matter according to claim 4 wherein water constitutes from 12% w/w to 17% w/w of the total composition.

Claim 9

A composition of matter according to claim 4 wherein the biopolymeric material constitutes from 0.5% w/w to 3% w/w of the total composition.

Claim 10

A composition of matter according to claim 1 wherein the aluminum constitutes from 0.2% w/w to 5% w/w of the total composition.

Claim 11

A composition of matter according to claim 1 wherein the aluminum constitutes from 1% w/w to 3% w/w of the total composition.

Claim 12

A composition of matter according to claim 4 wherein the biopolymeric material comprises matter prepared from a carbohydrate which has been reacted with a microorganism of the species Xanthomanas campestris.

Claim 13

A process for preparing a slurry explosive composition of claim 1 which process comprises firstly, preparing a mixture (I) comprising all of the water in the composition and a part of the oxygen releasing salt or salts; secondly, adding to said mixture (I) the biopolymeric material and allowing said biopolymeric material to hydrate at least in part to form a solution (II); thirdly, mixing said solution (II) with a blend comprising the residual part of the oxygen releasing salt or salts and the fuel material to form mixture (III); and, fourthly adding to said mixture (III) finely divided aluminum and dispersing it through the composition.

Claim 14

In a process of blasting which process comprises detonating an explosive composition at a wet blasting site the improvement that the explosive composition is a composition of claim 1.

Claim 17

A method according to claim 14 wherein the biopolymeric material comprises matter prepared from a carbohydrate which has been reacted with a microorganism of the species Xanthomonas campestris.

Claim 18

A method according to claim 14 wherein the biopolymeric material constitutes from 0.1% w/w to 5% w/w of the total composition.

Claim 19

A method according to claim 14 wherein the slurried explosive composition comprises additionally a sensitizing additive, and wherein the sensitizing additive is a finely divided metallic material passing a 300 mesh sieve.

Claim 20

A method according to claim 17 wherein the metallic material is aluminum.

Claim 21

A method according to claim 14 wherein the oxygen releasing salt is ammonium nitrate.