AU2022283710B2

AU2022283710B2 - Emulsion explosive composition containing PPAN

Info

Publication number: AU2022283710B2
Application number: AU2022283710A
Authority: AU
Inventors: Young In An; Moon Young Lim; Ha Na Woo
Original assignee: Hanwha Corp
Current assignee: Hanwha Corp
Priority date: 2021-12-07
Filing date: 2022-10-07
Publication date: 2024-07-18
Anticipated expiration: 2042-10-07
Also published as: AU2022283710A1; WO2023106586A1; KR102674075B1; KR20230085428A

Abstract

Disclosed is a PPAN-containing emulsion explosive composition including 40% to 80% by weight of an emulsion explosive composition and 20% to 60% by weight of porous prilled ammonium nitrate (PPAN) as an external oxidizer. The emulsion explosive composition includes (a) 70% to 95% by weight of an oxidizer aqueous solution comprising ammonium nitrate, calcium nitrate, and urea, (b) 0.1% to 10% by weight of an emulsifier, (c) 0.1% to 10% by weight of an oil phase, and (d) 0.1% to 10% by weight of an aliphatic adipate plasticizer serving as a heat-resistant plasticizer.

Description

DESCRIPTION EMULSION EXPLOSIVE COMPOSITION CONTAINING PPAN

Technical Field

The present disclosure relates to a PPAN-containing

emulsion explosive composition.

Background Art

Reactive grounds generally refer to areas containing

pyrite, such as sulfide, and contain chemical species capable

of reacting with a nitrate. Commercially available nitrate

based explosives may be deteriorated in stability and blasting

effect when used in reactive ground or when the temperature of

the ground rises. When a nitrate-based explosive is charged

into a hole in reactive ground, a nitrate component undergoes

reaction with a metal sulfide and an acid to produce heat,

which may cause an explosion to occur prematurely. These

premature explosions can cause continuous detonation of

explosives in adjacent bore holes, resulting in operator injury

or death.

When there is volcanic activity in reactive soil, or when

the temperature of the reactive soil is high, due to a rise in

geothermal temperature by solar radiation, a temperature

gradient due to an increase in the depth of the Earth's interior, or a temperature increase due to coal extraction, these reactions may occur more rapidly.

To inhibit reaction with nitrates, metal sulfides, and

acids, inhibitors such as phosphates, borates, zinc oxide,

urea, or liners can be used. However, there is a problem in

that the liner is expensive and difficult to handle. In

addition, leaks may occur during loading. Due to these

disadvantages, it is more stable and effective to use products

containing an inhibitor. Z.-X. Xu et. al. conducted a study on

the thermal behavior for the case in which pyrite and an

ammonium nitrate-based emulsion meet and react in the report

titled "Thermal Stability and Mechanism of Decomposition of

Emulsion Explosives in the Presence of Pyrite" (2015). DSC and

DTA/TG analysis confirmed that an emulsion gunpowder containing

urea as the inhibitor had the best thermal stability.

In general, emulsion explosives use an admixture of porous

prilled ammonium nitrate (PPAN) and an emulsion to increase

blasting power and sensitivity. In the case of inhibited

products including only urea, it is not possible to use an

emulsion explosive composition containing porous prilled

ammonium nitrate (PPAN) in reactive ground having a temperature

as high as 1000C. When the PPAN content in the emulsion

composition is 30% or more, the PPAN completely dissolves

within 1 to 2 hours at a temperature as high as 1000C, and the

emulsion separates into a water layer and an oil layer. Since emulsion is not a completely closed system, when the temperature of the emulsion reaches the high temperature, the emulsion begins to crack, making fine cracks. Therefore, the contents of the emulsion is exposed to high-temperature vapor through the fine cracks, and thus the PPAN is dissolved by the moisture.

Therefore, there is a need for the development of

technologies that can solve these problems.

Korean Patent Application Publication No. 2008-0083920

"Water-in-oil Emulsion Explosive" (published as of September 19,

2008) is a related art of the present disclosure.

Each document, reference, patent application or patent

cited in this text is expressly incorporated herein in their

entirety by reference, which means that it should be read and

considered by the reader as part of this text. That the document,

reference, patent application or patent cited in this text is

not repeated in this text is merely for reasons of conciseness.

Throughout the specification, unless the context requires

otherwise, the word "comprise" or variations such as "comprises"

or "comprising", will be understood to imply the inclusion of a

stated integer or group of integers but not the exclusion of

any other integer or group of integers.

Furthermore, throughout the specification, unless the

context requires otherwise, the word "include" or variations

such as "includes" or "including", will be understood to imply

the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Disclosure

Technical Problem

The present disclosure has been made to solve the

aforementioned problems, and

an objective of the present disclosure is to provide an

emulsion explosive composition including porous prilled ammonium

nitrate (PPAN), the composition having improved high-temperature

stability to be stably and safely used even in reactive ground.

Technical Solution

The present disclosure provides a PPAN-containing emulsion

explosive composition including

40% to 80% by weight of an emulsion explosive composition

and 20% to 60% by weight of porous prilled ammonium nitrate (PPAN)

as an external oxidizer.

The emulsion explosive composition includes:

(a) 70% to 95% by weight of an oxidizer aqueous solution

containing ammonium nitrate, calcium nitrate, and urea,

(b) 0.1% to 10% by weight of an emulsifier,

(c) 0.1% to 10% by weight of oil, and

(d) 0.1% to 10% by weight of an aliphatic adipate plasticizer

as a heat-resistant plasticizer.

In accordance with an aspect of the invention, there is

provided A PPAN-containing emulsion composition comprising:

40% to 80% by weight of an emulsion explosive composition and

20% to 60% by weight of porous prilled ammonium nitrate (PPAN) as

an external oxidizer,

wherein the emulsion explosive composition comprises (a) 70%

to 95% by weight of an oxidizer aqueous solution comprising ammonium

nitrate, calcium nitrate, and urea, (b) 0.1% to 10% by weight of

an emulsifier, (c) 0.1% to 10% by weight of an oil phase, and (d)

0.1% to 10% by weight of an aliphatic adipate plasticizer serving

as a heat-resistant plasticizer for high-temperature stability of

the emulsion,

wherein the aliphatic adipate plasticizer comprises one or

more plasticizers selected from the group consisting of dioctyl

adipate (DOA), di-iso-octyl adipate (DIOA), and di-isodexyl adipate

(DIDA).

Advantageous Effects

The PPAN-containing emulsion explosive composition of the

present invention has improved high-temperature stability.

Therefore, there is an effect that the PPAN-containing emulsion

explosive composition can be stably and safely used even in a high

temperature reactive ground.

Description of Drawings

FIG. 1 is a graph showing the results of stability evaluation

of an emulsion by storing a PPAN-containing emulsion explosive in

an oven heated to 1000C for 8 hours.

FIG. 2 is a graph showing the results of reactivity evaluation

of a PPAN-containing emulsion explosive in Experimental Example 3. 4a

Best Mode

Hereinafter, the present disclosure will be described in

detail.

An PPAN-containing emulsion composition according to the

present disclosure include 40% to 80% by weight of an emulsion

explosive composition and 20% to 60% by weight of porous

prilled ammonium nitrate (PPAN) as an externally introduced

oxidizer.

The emulsion explosive composition includes:

(a) 70% to 95% by weight of an oxidizer aqueous solution

containing ammonium nitrate, calcium nitrate, and urea,

(b) 0.1% to 10% by weight of an emulsifier,

(c) 0.1% to 10% by weight of oil, and

(d) 0.1% to 10% by weight of an aliphatic adipate

plasticizer as a heat-resistant plasticizer.

In general, emulsion explosives use an admixture of porous

prilled ammonium nitrate (PPAN) and an emulsion to increase

blasting power and sensitivity. When a simple inhibited

emulsion explosive composition is used in reactive ground with

a high temperature of 1000C or higher, there is a problem in

that the emulsion explosive composition is not allowed to

contain porous prilled ammonium nitrate (PPAN). When the PPAN

is admixed in the emulsion explosive composition, the PPAN

completely dissolves within 1 to 2 hours due to the high temperature, and the emulsion is separated into a water layer and an oil layer. Since the emulsion is not a completely closed system, when the temperature of the emulsion reaches the high temperature, the emulsion begins to crack, making fine cracks. Therefore, the contents of the emulsion is exposed to high-temperature vapor through the fine cracks, and thus the

PPAN is dissolved by the moisture.

Therefore, the present disclosure provides a solution to

the problem of the conventional PPAN-containing emulsion

explosive composition.

The oxidizer aqueous solution may be contained in an

amount of 70% to 95% by weight with respect to the total weight

of the emulsion explosive composition. When the proportion of

the oxidizer aqueous solution is outside the range, the

blasting power of the explosive is excessively high, resulting

in loss of submicro-vibration characteristics. When the

proportion of the oxidizer aqueous solution is excessively low,

the explosive may not be exploded.

In one embodiment of the present disclosure, the oxidizer

aqueous solution may include 30% to 60% of ammonium nitrate,

30% to 60% of calcium nitrate 30 to 60%, 1% to 20% of water,

and 1% to 20% of urea.

In one embodiment of the present disclosure, the

emulsifier preferably has a flash point of 1000C or higher, an

acid value of 7 to 8, and an amine value of 40 to 60.

The emulsifier is included in an amount of 0.1% to 10% by

weight relative to the total weight of the PAN-containing

emulsion explosive composition. When the content of the

emulsifier falls outside of the above range, an emulsion may

not be formed, or the explosive may not be exploded.

In one embodiment of the present disclosure, the

emulsifier may use one or more emulsifiers selected from the

group consisting of sorbitan mono oleate (SMO) and amine salt

of polyisobutylenesuccinicanhydride but is not limited thereto.

Preferably, the emulsifier may contain an amine salt of

polyisobutylenesuccinicanhydride having a flash point of 1000C

or higher, an acid value of 7 to 8, and an amine value of 40 to

60. The emulsifier may be composed only of an amine salt of

polyisobutylenesuccinicanhydride.

The oil is included in an amount of 0.1% to 10% by weight

relative to the total weight of the emulsion explosive

composition. The oil may include fuel oil and oil.

Preferably, the fuel oil may be a carbonaceous fuel oil

liquified at a temperature in a range of 500C to 800C. For

example, one or more oils selected from the group consisting of

wax, mineral oil, and light oil may be used.

As the oil, one or more oils selected from mineral oils,

lubricating oils, and the like may be used.

An aliphatic adipate plasticizer, which is one of the

heat-resistant plasticizers, may be included in an amount of

0.1% to 10% by weight relative to the total weight of the

emulsion explosive composition. When the aliphatic adipate

plasticizer is included in an amount less than the above

described range, the stability of the PPAN-containing emulsion

explosive composition may be insufficient in a high-temperature

reactive ground. When the content of the aliphatic adipate

plasticizer exceeds 10% by weight, it is not desirable because

the blasting power is reduced.

The aliphatic adipate plasticizer may be one or more

plasticizers selected from the group consisting of dioctyl

adipate (DOA), di-iso-octyl adipate (DIOA), and di-isodexyl

adipate (DIDA).

Herein below, the present disclosure will be described in

more detail with reference to examples described below. The

examples are intended to describe the present disclosure in

more detail but the scope of the present disclosure is not

limited by the examples. A number of changes may be made to

the following examples without departing from the scope of the

present disclosure.

Example 1: Preparation Of PPAN-containing Emulsion

Explosive

An oxidizer aqueous solution was prepared by mixing 10% by

weight of urea with 40% by weight of ammonium nitrate, 40% by weight of calcium nitrate, and 10% by weight of water.

Next, 90% by weight of the prepared oxidizer aqueous

solution was placed in a mixer and heated to and maintained at

700C. In another container, 3% by weight of mineral oil, 6% by

weight of dioctyl adipate (DOA) as a heat-resistant

plasticizer, and 1% by weigh of an emulsifier were heated to a

temperature of 50°C or higher and mixed uniformly. The

prepared mixtures were mixed in a mixer. When the nitrate

completely dissolved, the admixture was agitated at high speed

for 2 minutes for uniform blending. Thus, a composition of an

emulsion explosive was obtained.

Next, a PPAN-containing emulsion explosive composition was

prepared by mixing 70% by weight of an emulsion explosive

composition and 30% by weight of porous prilled ammonium

nitrate (PPAN).

Example 2: Preparation Of PPAN-containing Emulsion

Explosive

A PPAN-containing emulsion explosive composition was

prepared in the same manner as in Example 1, except that 50% by

weight of the emulsion explosive composition was mixed with 50%

by weight of porous prilled ammonium nitrate (PPAN).

Comparative Example 1: Preparation Of PPAN-containing

Emulsion Explosive

A PPAN-containing emulsion explosive composition (30% by

weight of PPAN) was prepared in the same manner as in Example 1

except that the content of mineral oil was increased to 9% by

weight and a heat-resistant plasticizer was not used.

Comparative Example 2: Preparation Of PPAN-containing

Emulsion Explosive

A PPAN-containing emulsion explosive composition (50% by

weight of PPAN) was prepared in the same manner as in Example 2

except that the content of mineral oil was increased to 9% by

weight and a heat-resistant plasticizer was not used.

Comparative Example 3: Preparation of Emulsion Explosive

Composition (PPAN not Included)

An oxidizer aqueous solution was prepared by mixing 10% by

weight of urea with 40% by weight of ammonium nitrate, 40% by

weight of calcium nitrate, and 10% by weight of water.

Next, 90% by weight of the prepared oxidizer aqueous

solution was placed in a mixer and heated to and maintained at

700C. In another container, 3% by weight of mineral oil, 6% by

weight of dioctyl adipate (DOA) as a heat-resistant

plasticizer, and 1% by weigh to of an emulsifier were heated to

a temperature of 50°C or higher and mixed uniformly. The

prepared mixtures were mixed in a mixer. When the nitrate

completely dissolved, the admixture was agitated at high speed for 2 minutes for uniform blending. Thus, a composition of an emulsion explosive was obtained.

Comparative Example 4: Preparation of Emulsion Explosive

Composition (PPAN not Included)

An oxidizer aqueous solution was prepared by mixing 40% by

weight of ammonium nitrate, 40% by weight of calcium nitrate,

and 20% by weight of water.

Next, 90% by weight of the prepared oxidizer aqueous

solution was placed in a mixer and heated to and maintained at

700C. In another container, 3% by weight of mineral oil, 6% by

weight of dioctyl adipate (DOA) as a heat-resistant

plasticizer, and 1% by weigh to of an emulsifier were heated to

a temperature of 50°C or higher and mixed uniformly. The

prepared mixtures were mixed in a mixer. When the nitrate

completely dissolved, the admixture was agitated at high speed

for 2 minutes for uniform blending. Thus, a composition of an

emulsion explosive was obtained.

Experimental Example 1: Stability Evaluation of PPAN

containing Emulsion Explosive

The PPAN-containing emulsion explosives of Examples 1 and

2 and Comparative Examples 1 and 2 were stored in an oven at

1000C for 8 hours to evaluate the emulsion stability. The

stability evaluation results are shown in FIG. 1.

As illustrated in FIG. 1, in the case of the PPAN

containing emulsion explosives of Comparative Examples 1 and 2

in which a heat-resistant plasticizer was not used, after 8

hours of storage, the emulsion was separated into a water layer

and a fuel layer, and the PPAN completely dissolved. On the

other hand, in the case of the PPAN-containing emulsion

explosives of Examples 1 and 2 in which a heat-resistant

plasticizer was used, the particle size of the PPAN was

slightly reduced, but no emulsion separation was observed.

These results indicate that the PPAN-containing emulsion

explosive compositions of the present disclosure have very good

stability in high-temperature environments.

Experimental Example 2: Evaluation of Performance after

Long-term Storage of PPAN-containing Emulsion Explosive

The PPAN-containing emulsion explosive prepared as in

Example 1 was stored in an oven at 1000C for 32 hours, and the

explosion speed was evaluated. The results are shown in Table

1 below.

[Table 1] Classificati Example 1 (70/30), 100 0C (m/s) Specific on gravity Shot Shot2 Average (g/cc)

Immediately 4100 3580 3840 after preparation 1.10

8 hours - 3945 3945 16 hours 3938 3829 3884 24 hours 3887 3685 3786 32 hours 4186 3850 4018

The results of Table 1 indicate that the PPAN-containing

emulsion explosive according to the present disclosure

maintains its initial performance even after 32 hours of

storage at 1000C. These results indicate that the PPAN

containing emulsion explosive composition of the present

disclosure does not change in performance even after a long

period of storage in high-temperature environments.

Experimental Example 3: Evaluation of Performance after

Long-term Storage of PPAN-containing Emulsion Explosive

The reactivity evaluation of Examples 1 and 2 was

performed according to a reactivity testing method prescribed

in Edition 4 of Australian Explosives Industry Safety Group

(AEISG) Code of Practice for Elevated Ground Temperature and

Reactive Ground.

The compositions of the emulsion explosives of Example 1,

Example 2, Comparative Example 3, and Comparative Example 4

were tested, and the test results were compared. The

composition of Example 1 contains 30% by weight of PPAN, the

composition of Example 2 contains 50% by weight of PPAN, the

composition of Comparative Example 3 does not contain PPAN, and

the composition of Comparative Example 4 does not contain PPAN and urea. While being in compliance with the reactivity testing method, the evaluation was performed using pyrite

(FeS2, 100%, 300 mesh, manufactured by Aldrich Company) instead

of actual lock due to an inability to supply of rock samples.

The results are shown in FIG. 2.

As shown in FIG. 2, the composition of the emulsion

explosive of the present disclosure did not react with pyrite

regardless of PPAN content, and no gas development was observed

on the naked eye.

In addition, in the case of the composition of the

emulsion explosive of Comparative Example 4 in which urea

serving as an inhibitor is not included, the temperature rose

rapidly as shown in the graph. However, in the case of

Examples 1, 2, and 3 in which urea is included, it was

confirmed that a temperature unchanging period is maintained

for more than 32 hours. This means that the PPAN-containing

emulsion explosive compositions of Examples 1 and 2 of the

present disclosure can be safely used without generation of NOx

in reactive grounds.

Claims

1. A PPAN-containing emulsion composition comprising:

40% to 80% by weight of an emulsion explosive composition

and 20% to 60% by weight of porous prilled ammonium nitrate (PPAN)

as an external oxidizer,

wherein the emulsion explosive composition comprises (a)

70% to 95% by weight of an oxidizer aqueous solution comprising

ammonium nitrate, calcium nitrate, and urea, (b) 0.1% to 10% by

weight of an emulsifier, (c) 0.1% to 10% by weight of an oil

phase, and (d) 0.1% to 10% by weight of an aliphatic adipate

plasticizer serving as a heat-resistant plasticizer for high

temperature stability of the emulsion,

wherein the aliphatic adipate plasticizer comprises one or

more plasticizers selected from the group consisting of dioctyl

adipate (DOA), di-iso-octyl adipate (DIOA), and di-isodexyl

adipate (DIDA).

2. The composition of claim 1, wherein the oxidizer aqueous

solution comprises 30% to 60% of ammonium nitrate, 30% to 60% of

calcium nitrate 30 to 60%, 1% to 20% of water, and 1% to 20% of

urea.

3. The composition of claim 1, wherein the emulsifier

comprises an amine salt of polyisobutylenesuccinicanhydride

(PIBSA) having a flash point of 1000C or higher, an acid value

of 7 to 8, and an amine value of 40 to 60.