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Explosives Types 16 June 2010

Orica USA Inc © 2010 1

Introduction to Orica North America

Types of Explosives

Technical TrainingOrica USA Inc

Course Objectives

• Discuss 1-2 applications for each of the main explosive types presented

• Describe the main differences between Low and High Explosives, and provide examples for each

• Locate Product Fact Sheets on the Mining Services website

• List 2-3 of the main properties for AN prills

• List 2-3 of the factors which affect ANFO’s performance

• Discuss why emulsions are such a popular type of explosive

• Distinguish between Primary, Secondary and Tertiary Explosives

Types of Explosives

One type of explosive is quite familiar to you…



Types of Explosives

Generally speaking, there are two types of explosives:

Low Explosives (e.g., black powder)

These explosives deflagrate (i.e., burn at a slow rate) rather than detonate and produce lower pressures;

used more as propellants

High Explosives (e.g., NG, dynamite)

These explosives detonate very rapidly and produce extremely high gas pressures; used more to break

and move large objects

Black Powder(also known as Gunpowder)

• Invented in 9th century by Chinese alchemists

• Burns by deflagration vs. detonation (Low Explosive) so better suited as a propellant than a blasting product

Ingredients are:

• saltpetre (KNO3) - oxidizer

• sulfur (S) - fuel

• charcoal or sugar (C) - fuel

Black Powder

Typical applications include:

• firearms (powder rifles), ammo (bullets) & cannons

• fireworks and fuses/primers

• signal flares and blank rounds

• limited blasting applications



Nitroglycerine (NG)

• NG 1st discovered by Ascario Sobrero in 1846

• Ingredients include nitric acid, sulfuric acid, glycerine

• In pure form, NG is a contact explosive which reacts via detonation(i.e., High Explosive)

• Uses include dynamites, heart medication, fuel in dragsters (Nitro dragsters, funny cars)

Dynamite

• In 1867, Alfred Nobel mixed NG with absorbants to produce dynamite – also blasting caps

• From the Greek dynamis meaning “power”

• Numerous applications in blasting

• Many dynamites have been replaced byless expensive, AN-based products such as watergels and emulsions

Dynamite is not TNT !

Semi Gelatin Dynamite ApplicationColumn Charge

NG-Sensitized DynamiteSurface and UG Blasting

Permissible DynamitesSpecialty Applications

Ammonia DynamitesDimension StoneQuarry and Construction

Nitroglycerine (NG) & DynamiteCurrent Orica NG/Dynamite Product Line



Ammonium Nitrate (AN)

• Is an essential ingredient in nearly all commercial explosives

• AN-based explosives represent over 80% of U.S. commercial explosives market

• NH3 + HNO3 ------> NH4NO3

• Production of AN prills comes in 2 forms:

(1) Agricultural grade – used as fertilizer

(2) Blasting grade – used as oxidizer in explosives

Ammonium Nitrate (AN)Prill Synthesis

Evaporator

Predryer

Dryer

Prills to Storage

Coater

Screen

Cooler

Oversize &Fines to Recycle

83% - 86% AN Solution

Prilled at 99% Melt

Ag GradeBlasting Grade

Prilled at 96% - 97%

Melt

Bypass Dryers

Prill Tower


Blasting grade AN prills have these main properties:

• resist crushing (low friability)

Prills Fines





• have a low density

• are affected by cycles (low, high) in temperature

Avoid crystallization!



• have low moisture content (no caking)

• have a porous surface for better fuel absorbency

AN & Fuel Oil (ANFO)

• Is the simplest commercial explosive available

• ANFO can be poured, packagedand mixed with emulsions for a variety of blasting needs

• Packaged ANFO is called Amex™

• Composed of a mixture of AN (94%) and #2 Diesel Fuel Oil (6%) by weight –

This ratio is critical!



ANFO

Factors affecting the performance of ANFO

• size of borehole into which it is placed (confinement)

• % of Fuel Oil in ANFO mixture

4" Confined Pipe

Expl

osiv

e Ve

loci

ty

Fuel Oil %

Unconfined

ANFO


• moisture in borehole desensitizes ANFO (not water resistant)

• the booster used to detonate ANFO

dry boreholes damp boreholes wet boreholes

ANFO


• density of ANFO used

ANFO @0.82-0.88 g/cc

ANFO @0.95-1.05 g/cc

pneumaticloading



ANFO


• density of ANFO used

ANFO @0.82-0.88 g/cc

ANFO @0.46-0.6 g/cc

blended withpolystyrene

Orica Flexigel

Types of Explosives

Orica North America AN and ANFO Product Line

Where can you access this information?

Product Fact Sheets are located at:

www.oricaminingservices.com

Here details of dimensions and case quantities are outlined (TDS) along with other data sheets (MSDS)

Product Fact Sheets



Product Fact Sheets

Select products here

Click here for MSDS pdf

Product Fact Sheets

Product MSDS Sheets



Click here for TDS pdf

Product Fact Sheets

Product TDS Sheets

Watergels

• Developed in the 1950s by Dr. Melvin Cook

• Until the 1980s were called slurries, now watergel is the preferred term

• Have a consistency similar to JelloTM



Watergels

• The cross-linking agent creates a gel, making the explosive water-resistant

cross-linking agent

• A watergel is a continuous, aqueous (water) phase containing dissolved materials including:

1. oxidizers2. fuels3. sensitizers4. cross-linking agent

Watergels

Some advantages of watergels over dynamites• are fairly insensitive to impact• no NG headaches• have rubbery consistency – can manipulate better

Orica NA Watergel Product Line

Emulsions

• Emulsions were developed in 1960s but not commercialized until 1970s

• By the 1980s, they replaced most slurries, watergels

• Currently they supply 15-16% of the commercial explosives market

• Emulsions make up the greatestdiversity of explosives products



Emulsions

Watergels

Example: JelloJello

Emulsions

Example: Miracle WhipMiracle Whip

Emulsions

Watergels

Example: JelloJello

Emulsions

Example: Miracle WhipMiracle Whip

EmulsionsAn emulsion is an intimate mixture of 2 immiscible

liquids where one liquid is uniformly dispersed throughout the other liquid

Continuous Phase – fuel (oil)

Interface - emulsifiers

Dispersed Phase – oxidizers (AN)

oil-soluble “head”

water-soluble “tail”

Emulsifier Molecule



Emulsions

The properties of emulsions allowed for the advancement of bulk delivery systems for explosives such as Orica’s Mobile Manufacturing Units® (MMU),

and the ability to manufacture explosive mixtures on site.

Advantages of emulsion explosives include

• Emulsions are very versatile – can be packaged, poured, blended

• Have very high explosve energy

• Can be handled safely

• Greater efficiency, reliability

• High degree of water resistance

• Minimized use of chemical sensitizers

Emulsions

Some emulsions

As stated earlier, explosives can be categorized as either Low Explosives or High Explosives

Classification of Explosives

deflagrationdeflagration detonationdetonation

Can you recall how they are distinguished?



Low Explosives

Examples of Explosives

ApplicationsExamples

• pyrotechnics

• blasting agents

• propellants black powder

AN

fireworks

High Explosives can be further categorized, based upon their sensitivities:


Primary

Secondary

Tertiarydecr

easi

ng se

nsiti

vity

decr

easi

ng se

nsiti

vity are extremely sensitive to mechanical shock,

friction and heat; respond by detonating

are relatively insensitive to shock, friction and heat; may burn or detonate when exposed to heat in small, unconfined quantities

very insensitive to shock, they require anexplosive booster made of secondary explosive

Primary Explosives


Examples Applications

• lead, sodium azides

• mercury fulminate

• lead styphnate

automobileair bags

i-kon™detonator



Safety Fuse

Powder Train

Iron Staple

Lead Azide / Lead StyphnatePrimer Charge – Primary Explosive

PETN Base Charge –Secondary Explosive

Primafuse ®

Secondary Explosives even can be further categorized by their composition:


Molecularconsisting of a chemically

pure compound

PETN crystals

oxidizer and fuel are on same molecule

Mixturesconsisting of an oxidizer

and a fuel

F AN

F

F

F

F

FF

FF F

F F

FF

FF

AN

AN

AN

AN

ANAN

ANAN

ANAN

AN

AN

AN

ANANAN

AN AN

oxidizer (AN) and fuel (F) are on different molecules

ANFO prills

Secondary Molecular Explosives



• NG

• HMX

• RDX

• PETN/TNT

dynamites

boosters

shock tube and detonating cord



Secondary Mixtures Explosives



• emulsions

• watergels

• Pentolite

Tertiary Explosives



• ANFO

bagged ANFO

bulk ANFO

Amex™

Summary of Explosive Types


Low(deflagration)

black powder,gunpowder

High(detonation)

Primary (very sensitive)

lead azide, sodium azide, lead styphnate

Secondary (insensitive)

Tertiary (very insensitive)

ANFO

Molecular NG, TNT, PETN,

HMX, BDX

Mixtures emulsions, water gels, Pentolite



Explosives Types Review

Put your thinking caps on….

…we’re going to play Jeopardy!

Explosives Types Review

Orica Jeopardy Rules1. Divide into 3 teams2. Designate team captains - They hold

noisemaker3. Only captain can ring in4. Anyone can answer but must answer

within 3 seconds of ringing in5. No 2nd answers!6. Correct answer controls board

Who says blasters don’t have a sense of humor?

Module: Types of Explosives Intro to Orica NA Course Course Date: 15 June 2010

Page 1

Slide Talking Points or Action Training Resources

Temperature check – Encourage participants to ask questions of topics that might confuse them

• Extra pens, pencils • Bags of assorted candies • Laptop and power source (backup?) • Projectors (backup) • Laser pointer • Automatic slide advancer • Speakers

1. As in the last module, this one will be technical in nature where we will apply the information learned in previous modules 2. Before moving on, ask what ONE word comes to mind when you think of explosives… ask around room….THEN advance the slide

Many people think of the word FIREWORKS…. This video clip (ca. 20 seconds) of fireworks is designed as an attention-getter – Point out that the properties of fireworks are the same as the properties of explosives just discussed in previous module

• Be sure speakers are connected

Emphasize the terms deflagration and detonation as they are key terms in this module


Page 2

In this section, participants will look at different examples of explosives and relate some of the properties learned earlier to them

No talking points here

Point out the 3 NO3 (nitrate) groups on the molecule above – Compare to AN (N=nitrate) – Nitrate groups are chemically very active and thus their use in many explosives

Dynamites were the mainstay in the explosives industry for over 130 years but their use, as indicated in the last point, has declined to about a 2% market share in the US today among all explosives sold

Even with such a low market overall, there are still places and circumstances where dynamite and NG use are preferred – especially in international markets where it is considerably less expensive to use than other products


Page 3

Emphasize the last point: There are indeed different types of AN prills, each with a different energy content due to the way they are manufactured. Blasting prills tend to be less dense (affects explosive sensitivity) and have a more porous surface (affects how well will accept coatings such as FO, provide “hot spots” for ignition points)

Prill is formed as it moves through a prill tower: 1. At top, AN solution is sprayed through shower heads – liquid AN droplets form and free fall 2. After falling 100-200 feet, droplets cool and crystallize into spherical prills 3. Further down in tower, they are dried, cooled, screened for size, then coatings applied

Friability = ease of crushing

Point out that crystallization in explosives is very undesirable as it affects explosive sensitivity

1.Caking is undesirable as it can clog up the distribution system of AN 2.Point out desirability of having a porous surface to application of FO on prill


Page 4

The critical ratio of 94:6 is due to Oxygen balance – Recall that the amount of oxidizer (oxygen) is significant to an explosive’s properties

Point out both variables on graph and how they are related to explosive velocity and to one another

Briefly talk to each point above: 1.Water is a major concern in blasting 2.Primers can be composed of different explosives, different sizes

Show that pneumatic loading involves using air pressure to force product into borehole, effectively compacting explosive and increasing its density

Here, one of Orica’s products adds very small polystyrene balls to the ANFO to create space between prills and effectively reduce its density

• See if Jeannyne, Liz have samples of polystyrene


Page 5

This next section will show participants how they can obtain product information for any Orica product line in NA

Ask how many participants have ever visited this website – It’s probably good to have it bookmarked along with The Globe and a few more that we’ll show today

This is the front end to the new and improved Orica NA website

Ask participants if they know what “MSDS” means (Material Safety Data Sheet)

These are in pdf format


Page 6

Ask participants if they know what “TDS” means (Technical Data Sheet)

Again, these are in pdf format – Some documents have images and/or logos, many do not

1. Watergels represented the birth of the water-based explosive industry that share market dominance with ANFO-based products 2. In the left diagram, the pellets are aluminum which are added as a fuel

Cross-linkers here are analogous to emulsifiers which we’ll see later in emulsion explosives

The Apex Super 3000 and Apex Super 6000 are Orica’s watergel products


Page 7

No talking points here

• Pass around sample chubs, actual emulsion samples in jars (if possible) get from Marketing

There are 2 slides here Think about the consistency of each of the above to help visualize the 2 products

1. Again, the emulsifier here is similar in function to the cross-linkers in watergels in that they help “hold” things together 2. The fuel oil (non-polar molecule) and the oxidizer (polar molecule) tend not to associate physically – The emulsifier prevents them from dispersing by physically connecting to both FO and oxidizer – It has two ends which are chemically different, each of which associates with one or the other FO or oxidizer

MMUs are a significant component to Orica’s delivery systems – They have the world’s largest fleet of such vehicles. Point out different compartments on truck diagram and briefly talk to them.

No talking points


Page 8

Ask for participants to answer this question

No talking points

Most commercial explosives belong to the Tertiary category

The i-kon example will be illustrated in greater detail on the next slide

Relate primary and secondary explosives to previous slide


Page 9

Be sure to clarify the distinction between secondary molecular and secondary mixture explosives….

Molecular explosives tend to be more expensive – Used in smaller amounts

Secondary mixtures have a variety of applications – These products tend to dominate the bulk explosives lines

Recall that these explosives: 1. are very insensitive and require another explosive to detonate, 2. contain fuel and oxidizer, 3. are used primarily in mining - and unfortunately terrorism

No talking points – Ask participants along the way to fill in the “missing” pieces


Page 10

Put your thinking caps on! We’re gonna play Jeopardy!

1. Regular Jeopardy rules save for these…. 2. Keep score of 3 teams using whiteboard

• Be sure that Jeopardy game plays • Whiteboard/markers • 3 noisemakers

Shirt from 2007 Basic course in Pittsburgh!

Types of Explosives - Todd Bennethum Home Page · Types of Explosives Technical Training Orica USA...

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