Note: Descriptions are shown in the official language in which they were submitted.
ICIA 1394
~ 3 3 î ~
EMULSION EXPLOSIVE-CONTAINING COMPOSITION HAVING A HIGH VELOCITY
The present lnvent10n relates to an exploslve
composltlon ~nd ln p~rt1cul2r to such ~ compos1tlon
compr1sln9 ~ blend of ~n emulslon explostve and
sol1d ~mmontum nltrote p3rt1cles.
Emulslon exploslve compos1tlon~ have been widely
~cceptet ln the explos~es 1ndustr~ because of thelr
~xcellent ~xpl~slv- propertles and ease of handl1ns.
~he omul~1Dn exptos1ve compos~t~ons now 1n common
use 1n th~ 1ndustry were 1rst d~sclo5e~ by Bluhm ln
Un1ted States ~tent No. 3 447 978 ond comprlse ~s
components~ a discontlnuous aqueous phase ~ ~
compr1s1ng dtscr~te droplets of ~n ~ueous solut10n ~: :
of lnorg~nlc oxygcn-rele~s1nD s~lts; (b) a
contlnuous w~ter-1mm~sc1ble org~n1c phase throu~hout
~ 15 wh1ch the droplet~ ~re dlsperse~; (C) ~n emutslfler
I wh1ch forms ~n omuls10n of th~ dropl~ts of ox1d1zer
s~lt solutlon throu~hout the cont~n~ous organ1c -~
pho3~; ~nd (d) ~ d1scontlnuous oasaous ph~se.
B
1331~14 ::
-2-
.: '- ~ ~.
More recently explosive compositions which comprise a
blend of a water-in-oil emulsion and a solid particulate
ammonium nitrate (AN) such as ammonium nitrate prills or
ammonium nitrate prills coated with fuel oil (referred to
as ANFO) have become popular because of the reductions in
cost due to the inclusion of a significant propoxtion, for
example, 5 to 50% of AN.
Compositions comprising blends of a water-in-oil emulsion
and AN (or ANFO) are described, for example, in Australian
Patent Application No. 29408/71 (Butterworth) published
November 30, 1973 and US Patents 3 161 551 (Egly et al)
published December 15, 1964, and 4 357 184 (Binet et al)
published November 2, 1982. A serious problem of prior
art blends is evident when loading the compositions into
wet bore holes.
Although the tendency of the solid AN prill to break up or `
dissolve in water is reduced somewhat by the presence of
the emulsion component, collar loading of prior art
emulsion/prill blends into water-containing bore holes
results in a significant reduction in blast performance.
As a result it has hitherto been necessary when loading
emulsion/AN blends into water-containing bore-holes to
pump the product to the bottom of the holes using a long
delivery hose and to fill the hole by displacing water
above the rising explosive column.
This pumping technique however does not allow the rapid
loading rates that can be achieved when loading the blends
from the top of bore-holes using techniques such as
augering. Consequently as well as having to accept a
slower loading rate in wet bore-holes, frequent users of
such explosives have been forced to maintain two sets of
equipment for loading bore-holes according to the
prevailing weather conditions.
,
, .,
~331~ ~
--3--
We have now found that by selecting a water-in-oil
emulsion having a viscosity in the range of from 25,000 to
60,000 cps the water resistance of a blend of water-in-oil
emulsion and solid particulate ammonium nitrate is
significantly increased while the blend retains a
consistency suitable for collar-loading.
Accordingly, we provide an explosive composition
comprising a blend o~ 45 to 95% by weight of the
composition of a water-in-oil emulsion comprising a
discontinuous aqueous phase comprising at least one
oxygen-releasing salt, a continuous water-immiscible
organic phase and a water-in-oil emulsifying agent; and 5
to 55% by weight of the composition of solid particulate
ammonium nitrate and wherein the Brookfield Viscosity of
the water-in-oil emulsion is in the range of from 25,000
to 60jO00 cps.
Where used herein the term Brookfield Viscosity refers to
the viscosity measured at 60C using a Brookfield*RVT
Viscometer No. 7 spindle at 50 rpm. It preferred that the
Brookfield Viscosity of the water-in-oil emulsion be in
the range of 28,000 to 40,000 cps.
A variety of factors influence the viscosity of the
emulsion component. For example, the nature of the oil
and the water-in-oil emulsifier as well as their
interaction. These features may be balanced without undue
experimentation to provide a Brookfield Viscosity within
the characterising range of from 25,000 to 60,000 cps. ~
,-: :~:
:~
*Trade Mark -~
'~
.
: :~
~ ~ .
: ~ ~
~,,", ~ "~
1 3 3 ~
- 4 -
Th~ emulslon exp~os1vQ component of the compos1tion
~2y conta1n ~diuvants, ~or exa~ple, vo1d a~ents Such
as ~s bubbles, porous p~rt1cles or balloons to
rQ~uce the dens1ty o~ent wh1ch st~b111ze vo1d agents
~nd sol1d p~rtlcul~te ~aterl~1 such as c~rbon or
~lum1n1u~.
Such mater1~1s 1nfluence the vlscos1ty o~ the
compos1t10n ~s does the ~ol1d part~culate ammon1u~,
n1trAte ~nd the Brookf1eld Vlscoslty of the ~-
lo water 1n-oil omuls10n ls therefore deter~lned on the
w~ter-ln-o11 e~ lon devold of ~dJuvants.
The water-l~m1sc1ble or~nlc phase component of the
w~ter-1n-oll e~uls10n of the composit10n of the
1nvent10n comprlses the continuous "o~l" phase of
t~.e w~ter~ln-o11 emuls10n ~nd 1s the fuel. Exa~ples
of oro~n1c fu~ls lnclude allphat~c, ~11cycllc ant
~rom~t1~ compounds ~nd ml~tunes thereof whlch ~re in
the 11qu1d state ~t the ~ormul~tlon te~perature.
Su1t~ble oro-n1c ~uels m~y be chosen from fuel o11,
dlesel o~l, distillate, kerosene,
n~phtha, ~%ss ~eg. m1crocryst~111ne wax, paroff1n
w~x ~nd sl~ck w~x), p~roff1n o11s, benzene, toluene,
x~l~nes, ~sDh~ltlc mater1~1s, polymerlc o11s such ~s
the low molecul-r we1aht poly~ers of olef1ns, an1m~
o11s, flsh olls, ~nd other mlneral, hydroc~rbon or
~atty olls, ~nd mlx~uros thereof, Preferred or~2nic ~ -~
fuets ~re 11qu1d hydroc~r~ons g~ner~lly referred to
~s petroleum d1st111~tes Such as gasoline, kerosene,
~uel 0115, furn~co o11s, ~nd p~raff1n oils.
Typ~c~lly, tho orp~n1c fuel of th~ cont1nuous ph~o ~:
of the w~tor-ln-o11 emuls10n component comprises
trom 2 to 154 by weloht ~nd preferobly 3 to 10% by
;~ wel~ht of th~ w~ter-1n-oll emuls10n component sf the ~ ;
~ exploslv- composltlon of the lnvent10n.
;~: :
~ B
: ' ' :`--
~:~
1 33 ~
.-` 5
typ1cally we h~ found th~ o11s h-v1ng ~ vl~coslty
lr the r~nge o~ from 4 ~o lO00 ~nd prof~r~bly 6 to ,
200 c~ntl-~tok~s ar~ p~rtlcul~rly ~u1tod ~o
~rov1dlng ~ water-1n-ol 1 emuls1On h~vlng the
5 c~,~racterl~t1c Y1sco~lty ran~ ot from 25,000 to
6C,0~0 cps
l~ ls p~rt1cularly ~r~fe~red th~t the or~an~c ~uel
0' th2 e~ul~lon component o~ the eomposlt10ns of the
1~vent10n co~prls~ ~t l~ast one p~afftn1c o11.
Gen~r~ 1t has bcen the pr~ctlce 1n thQ ~r~ to ~se
d~-sel otl or No 2 fu-l o11 1n the emulslon ph~se
cf e~ulslon/AN blonds However we h~Ye foun~ th~t
tte use ot par~ff~n1c o11s ~s part~cul~rly sulted to
prod~c1ng blends havtno h1gh re~1st~nc~ to w~ter
aLsorptlon
emulslfy1nc agent of the w~er-1n-oil ~ulslon
m~y be selQcted trom thc wlde rang- of e~ulslfy1ng ' ~-
a;ents known 1n the ~rt; Ex~plcs of ~uls1fyln~
a ents 1~1cude ~lcohol ~lkoxyl~t~s, phenol
20 ~lkoxyl~tns, poly(oxy~lkylen~ ~lytols,
pcly~oxy~lkylen~ tatty ~c~d est~rs, ~mlnc
~lkoxy1~tns, fatty acld esters of sor~ltol ~nd
glyçorol, fatty ~cld s~ltS, sorblt~n nsters, poly~
~exyl1kyl~ne) sor~1tan ~st~rs, f~tty ~m1ne
25 ~t~oxyl~t~s, poly~oxy~ yl~nQ~ glycol ~sters, fatt~
~c1d ~mld~s, f~tty ~cld ~mlde alkoxylat-s, f~tty
~e1nes, quatern~ry amtnes, ~lkylox~201~n~s,
~7~onylox~zot1nes, lmld~zol1nes, elkyl~sutfon~tes,
~l~yl~rylsulfon~tes, ~lkylsulfos~ccln~t~s,
30 sl~ylphosph~es, ~lkenylphosph~tes, phosph~te
es:-rs, te~1thln, copolymers of poly~oxy~lkylene1
olYcol~ ~n~ polyt12-hydroxy-tc~rlc c1d3, ~n~
m1xturrs ther~of A~on~ th~ pref~rr~d ~muls1~y1ng
~g~nts ~r~ the 2-~kyl- ~nd 2--lk~nyl-e,~'-b1s
.
1331~1A
(hydroxymethyl)oxazoline, the fatty acid esters of
sorbitol, lecithin, copolymers of poly(oxyalkylene)
glycols and poly~12-hydroxystearic acid), and mixtures
thereof, and particularly sorbitan mono-oleate, sorbitan
sesquioleate, 2-oleyl- 4,4'-bis(hydroxymethyl) oxazoline,
mixture of sorbitan sesquioleate, lecithin and a copolymer
of poly(oxyalkylene) glycol and poly (12-hydroxystearic
acid), poly[alk(en)yl]succinic acid and derivatives
thereof, and mixtures thereof.
Although a range of emulsifying agents may be used in
preparing compositions of the invention we have found that
a particularly high water resistance is provided where the
water-in-oil emulsion component has a viscosity in the
range of 25,000 to 60,000 cps and the emulsifying agent
component comprises a condensa'ion product of an amine and
a poly[alk(en)yl]succinic acid and/or anhydride.
Typical examples of condensation products of an amine and
poly[alk(en)yl]succinic acid and/or anhydride may include
esters, imides, amides, and mixtures thereof. Preferably, ;
said emulsifier has an average molecular weight in the ~
range 400 to 5000. ~ ;
In said poly[alk(en)yl]succinic acid-based emulsifier it
is preferred that the hydrocarbon chain is derived from
polymerization of a mono-olefin and generally the polymer ~ -
chain will contain from 40 to 500 carbon atoms.
Preferably the poly[alk(en)yl] moiety is derived from
olefins containing from 2 to 6 carbon atoms and in
particular from ethylene, propylene, 1-butene and
isobutene. The emulsifier may be derived from
poly~alk(en)yl]succinic anhydride. Such emulsifiers
;
--7--
1 3 3 ~
derivatives are disclosed in Australian Patent, Patent
Application No. 40006/85 published September 26, 1985.
Such derivatives are commercially-available materials
which are made by an addition reaction between a
polyolefin containing a terminal unsaturated group and
maleic anhydride, optionally in the presence of a halogen
containing catalyst. The succinic acid or anhydride
residue in the above compounds may be reacted to introduce
a polar group. Generally the said polar group is ;
monomeric oligomeric groupings containing not more than
about 10 repeat units may be employed. Examples of ~ -
suitable polar groups may include "olar groups derived
from polyols such as glycerol, pentaerythritol, and
sorbitol or an internal anhydride thereof (e.g. sorbitan);
from amines such as ethylene diamine, tetraethylene
triamine and dimethylaminopropylamine; and from
heterocyclics such as oxazoline or imidazoline. Suitable
oligomeric groupings include short-chain poly(oxyethylene)
groups (i.e. those containing up to 10 ethylene oxide ; ~-
units)~
Formation of emulsifiers for use in accordance with the
invention may be effected by conventional procedures
depending upon their chemical nature.
In order to prepare a derivative of
poly(alk(en)yl)succinic acid comprising a polar group
derived from an alcohol or amine, the acid group or
anhydride thereof can be caused to react with the hydroxyl
or amino group by heating the two components together in a
suitable solvent, in the presence of a catalyst if
desired. -~
: : i~
~ . ~ .. . ~ . . . . . ~ . .
--8--
1 3 3 ~
The emulsifiers may be of a non-ionic character, but they
may alternatively be anionic or cationic in nature, as,
for example, where the hydrophilic moiety incorporates the
residue of a polyamine or a heterocyclic compound.
Preferred emulsifiers are poly(isobutylene)succinic
anhydride derivatives and most preferably condensates
thereof with amines such as ethanolamine. `
Typically, the emulsifying agent component of the
composition of the present invention comprises up to 5~ by
weight of the emulsion component of the composition.
Higher proportions of the emulsifying agent may be used
and may serve as a supplemental fuel for the composition
but in general it is not necessary to add more than 5% by
weight of emulsifying agent to achieve the desired effect.
In particular we have found that the use of a
poly(isobutylene)succinic anhydride/amine condensation
product in combination with a paraffinic oil in the
composition of the invention provides particularly good
water resistance and is well suited for collar loading
into significant volumes of water.
It is preferred that the composition of the invention
further comprises voiding agents which may, for example,
be in the form of fine gas bubbles dispersed through the
composition, hollow particles (often referred to as ~ i
microballoons), porous particles or mixtures thereof.
Techniques for preparing gassed emulsion explosives are
well known in the art and include mechanical agitation,
injection or bubbling the gas through the composition,
~ :'
~. ,
1331~1~
or chemical generation of the gas in situ.
The preferred process for introducing a gaseous phase is
by in situ chemical gassing. Suitable chemicals for the
in situ generation of gas bubbles include peroxides, such
as hydrogen peroxide, peroxide nitrates, such as sodium
nitrite, nitrosamines, such as N, N1-dinitrosopenta-
methylene tetramine, alkali metal borohydrides and alkali
metal carbonates, such as sodium carbonate. Catalytic
agents such as thiocyanate or thiourea may be used to
accelerate the decomposition of a nitrite gassing agent.
. ', ::, '-"
Where used the voiding agent may be added before or after
the emulsion is blended with the ammonium nitrate
particles however it is generally preferred that the
voiding agent is added to a blend of the emulsion and
parti~,les. ~;~
Typically the voiding agent comprises 0.05 to 50% by
volume of the emulsion explosive component at ambient
temperature and pressure. More preferably, where used,
the voiding agent is present in the range 10 to 30% by
volume of the emulsion explosive component and preferably
the preferred bubble size of occluded gas is below 200 -
microns. More preferably, at least 50% of the gas
component will be in the form of bubbles or microspheres
of 20 to 200 microns internal diameter. -
We have found that the presence of a dispersed gaseous
phase significantly improved the water resistance of the
composition of the invention when a gas bubble stabilising
agent is also present. Such agents are described in our
~ .
--10--
1331~1~
copending Australian Patent Application No. 40968/85
published October 24, 1985.
Accordingly we further provide an explosive composition
comprising from 45 to 95 percent by weight of the total
composition of a water-in-oil emulsion comprising a -~
discontinuous aqueous phase comprising at least one
oxygen-releasing salt, a continuous water immiscible
organic phase, a water-in-oil emulsifying agent and at
least one agent capable of facilitating the production of
lo gas bubbles in the presence of said water immiscible
organic phase; and 5 to 55% by weight of the total
composition of solid particulate ammonium nitrate; and
wherein said water-in-oil emulsifying agent is selected
from the group consisting of condensation products of an
15 amine and a polyl[alk(en)yl]succinic acid and/or anhydride
and mixtures thereof.
The ability of various agents to facilitate the production
of small gas bubbles in compositions of the invention may
be determined by a foam stabilization test.
20 Accordingly in another aspect of the invention there is
provided an explosive composition as hereinbefore
described wherein the agent referred to therein is
characterized further in that it has properties which
provide a suitable stabilizing effect and which are
25 established by means of a foam stabilization test as
hereinafter described.
In the said foam stabilization test 0.2 part by weight of
active ingredient of the candidate agent or mixture of
agents to be tested is added to and mixed with 100 parts
30 by weight of diesel fuel. 5 ml of the mixture is placed
in a graduated cylindrical vessel of 15 mm internal
~'
-11- ',~ ''
1 3 3 1 ~ 1 4
diameter. The mixture is shaken for 15 seconds. A foam
forms on the surface of the mixture. The volume (V5) of
the foam is measured 5 minutes after the mixture has
ceased to be shaken using the graduations on the vessel. ;~
The foam volume (V60) is measured again 60 minutes after -~
the mixture has ceased to be shaken, the vessel and the
mixture being kept at a temperature of 18 to 22C during -~
this period of time. A foam stability parameter 06 / S iS
calculated from the foam volumes by means of the formula
::
~6 / S = V6 o
V5
It has been found that those agents or mixtures of agents
in which the V5 value was equal to or greater than 1 cubic
centimetre and had a 06 / S equal to or greater than 0.3
impart the desired gas bubble stablization effect of this
embodiment of the invention. Hence the foam stabilizing
agents preferred for use in the compositions of the
invention are those having a Vs value equal to or greater
than 1 cubic centimetre and a 06 I S value equal to or ~ ~
greater than 0.3 as determined by the foam stabilization ~-
test hereinbefore described.
The most preferred gas bubble stabilising agents are
non-ionic fluoroalkyl esters such as are available under
the trade name "FLUORAD"*.
Typically when used the gas bubble stabilising agent will
be present in the range of 0.0001 to 5.0% by weight of the
emulsion component of the composition and preferably in
the range 0.001 to 1%.
: .~
~ * Trade Mark
- ' .
-" -12- ~ 3 3 ~
su1e~bl~ oxyoen-rele~s1ng ~lts for use ln t~e
~quoous ph~st component o- the composltlon o~ th~
pr~sent 1nventton ~ncluCe ehe ~lk~ nd ~lk~tlno
~rth met~l n1tr~t~s, ch~orates ~nd perchlor~tes, ;~
5 ~monlum nltr~te, ammonlum ~hlor~t-, ~m~on1um
perchlor~te ~nd m~xt~res therQ~. ~he pr~ferred
oxy~en-rele~s1ng s~lts ~nclude ~mmon1um n~tret~,
sodlum nltrate ~nd c~lclum n~trate. More prefera~ly
t~e oxysen-role~stng salt compr1slng ~m00nium
nltr~te or ~ ~1xturo o~ ~mmon~um n1tr~te and soctlum
or c~lc1um n1tr~tes.
Typ1c~11y, th~ oxy~en-r~le~slno s~lt of tho ~muls~on
componont of thc com~os1t10ns of the present
1nventton compr1ses from 45 to 95S ~nd preferably
lS fro~ 60 to 90% ~y we~9ht of the tot~l e~ulslon
component of the compos~tton. In oomposlttons
~hereln the oxyQen-r~leas1ng s~lt comprises
1xture of ~mon1um n~tr~te ~nd sod1u~ n1tr-te the :
pr-~crred composttlon r~nge ~or such a ~l~n~ ~s from ~
20 S to 80 p~rts of sod1um nttr~te for e~er~ ~00 p~rts ::
o~ ~mmon1um n1tr~t-. T~erefore, ln the ~referrod
co~pos1t10ns of the present 1nventlon the ~:
o~yo~n-rele~1n~ s~lt compon~nt co~pr1ses from 45 to
~04 by weloht ~o~ the c~ulslon component) ~monlum
2s n~tr~t~ o~ ~1xturts o~ from 0 to 40~ by ~ei~ht (of
t~.o omuls10n component) ~mmonlum n1tr~t~
T~p1c~11y, the ~mount of w~ter cmployed 1n the
co~po~1t10n ôf the present lnvent10n ~s 1n the r-n~e
of from I to ~04 by w~ht of the emuls10n
component. Pre~er~bly the ~mount employ~d 1s ~rom
~; tc 254, ~nd ~ore prefer~bly from 6 to ~4 by we1cht
o~ th~ ~mul~ion component.
;~
13- 1 3 3 1 ~
ProfQr~bly th~ r~tlo o- whter-ln-o11 ~mul~10nsso~id ~-
p~rt1culat~ ammonlum nltr~t~ ls ln the r~no~ 45~55 1
to ~0 30 ~nd more p~e~er~ly 45 S5 to ~0 40
She ~erm a~monlum nltrate p~rtlcles 1s used hereln
to ~ncompass co~posltlons of pr1110d ~mmon1um
n1~r~te wh1e~ m~y o~tlon~lly ~e co~t~d wlth ~ fuel ~ -
co~ponent ~uch ~s 1n th~ c~se of the w~17 known AN~0 1
composlt10ns, !
~yp~c~llr the solla p~rt1cul2te am~on1Ym nltrate
lo ~111 comprlse up to lG~ ~w sf fuel o11 w1th about
6~ b-lng pr~err~d, At ~out 6~ the ~11d
parttcul~t~ ~mmon1um n1tr~te t~ essentt~l1y ,-
oxy~n-b~lanced
~ urther embod1~e~t of the lnvent~on t~ere 1s
15 pr~vlded a process for prepartng the compos~t10n
herelnbe~oro dQscrtbe~, the process co~prlses
blondln~ from 45 to 95 ~rts by we10ht of ~
~er-1n-o11 muls~on ~n~ from 5 to 55 p~rts by
w-1~ht of ~ solld ~rttcul~te ~mmonlum n1trate
20 ~ watcr-1n-o11 emuls10n m~y b~ prep~red ln
pr~ lnary procedur~ compr1slng s
:
dlssolv1no the oxyg~n-rolt~sln~ solt 1n w~ter
~t a temper~ture ~ove th~ ~udge polnt of the
salt solutlon, prefer~bly ~t ~ temperatur- in
th~ ~an~t from 25 to }10, to ~1ve ~n ~qUeOU5
s~lt solutlon;
combln1n~ th- aqueo~s s-lt solu~10n, the
w~ter~1mm1sclble oro-nle ph~s~ ~nd ~h~
wator-ln-oll emulstfylng ~gent ~1th r~p1d
~1xlno to for~ ~ w~ter-ln-o11 orul~10n; ~nd
,~
~ - -14- 133~
~1~1ng unt11 th~ omulston ls ~n1~orm.
ln a pr~forrct ,~mbod1ment of th1s p~ocess th~ :
proces~ further compr1scs mlx~ng wlth th~ emulston ~:
compon,~nt or one or mor~ constltuents theraof a ~as ~-
5 ~ubbl,e st~b1~1~1ng ~gent ,~nd an a~ent ca~able of ~- -
ln ~ltu g~neratlon o~ 9~s b~b~l-S.
.: ~
As her~lnbefore d1scussed She presen$ lnv~n~10n
~ro~1des slgn1~c~nt ,~dvantagQs ln load1ng of wat~r
conta1nlng bor,~-holes.
10 ~ccord~ng~y we further prov~d,~ a ~ethod of loading a , :
~ter-cont-1n1nc bore-hole comprlsSng pour1ng an
exploslve heri~lnbcfor~ descr1~ed tnto the :
~ater-contalnlnt borehole fro~ a poslt10n adJacent
the collar of the ~ter-tonteln1ng bore-hole.
By the term "pour1ng" lt ls mesnt that the explos1ve
compos1tlon ls rcle~sed fro~ 1ts co~ta1nment or i~
tr~nsport means. It 1s pre~erred th~t the exploslve
compos~t10n ls ouctred to the coltar of the
~cra-holc ~nd rele~sed from ,~ poslt10n a~ove the
20 c O ~
~'e llso prov1de ~ ~sthod of bl~stlng 1n ~,
~oter-cont~lnlng bor~ole tomprls1ng the steps of
ls~d1ng ~ water-cont~tnlng bore-hole as here1nbefore
C-scr1bed ~nd detonat1n~ the explos1v~.
lt ls ~ p~rttcYl~r adv~nt~ge of our composttlons
tk~t th~y detonate well evon wh~n poure,~ from
~d~,lcent th- coll,~r of the borehol- 1nto slgnif1cant
~epths of water.
ptc~lly composlttons of o~r ~nventlon ~ay be
~etonat~ su~c~s~fully ~ven whon the exploslv~wa~en
~i
- -15- ~331~4
~1ght r~t10 15 l~S5 thdn lO ~n~ pl~fer-bly ln th~
r~nge o~ from 1~1 tQ 6/l. ~;
~e ~lso provld~ a method Of ~ldstlng comprlsln9
deton~t1n~ an ~xplosivo co~posltlon ~S h~relnd~o~e .
5 tescrlbed ln w~er wher1n thQ exp10sl~eJwater w~1~ht
r~t~o 1s less ~hdn lO, preferably ln the ran9e of
~rom ~/1 to 6~1.
-
. ~
-16-
13 3 1 514
The invention is now demonstrated by but in no way limited
to the following examples in which the term Brookfield : .
Viscosity is used to refer to measurements carried out at
20C using a Brookfield Viscometer No. 7 spindle at 50
rpm.
Example 1 and Comparative Example A
The Explosives of Example 1 and Comparative Example A
having the compositions as shown in ~'able 1 were prepared
according to the following procedure. :~
TABLE 1
Example 1 CE A
Parts w/w Parts w/w
: Emulsion component
Ammonium nitrate22.77 22.77
Calcium nitrate20.32 20.32
Water 6.85 6.85
Acetic acid 0.48 0.48
Distillate (oil) - 4.20
Sorbitan mono-oleate - 0.84
Paraffin (oil) 4.2
* PIBSA emulsifier 0.84
Ammonium nitrate particles
ANF0 44-7 44-7
Gas bubkle stabiliser
"FLUORAD", 5% solution . '
in distillate 0.3 0.3
Gasser agent 0.1 0.1
(solution of 15%
sodium nitrite
and 30~ sodium
thiocyanate in
;~ water)
~ .
~ ~ .
1 3 3 ~ 4
-17-
* The PIBSA emulsifier used was a 1:1 molar condensate of
polyisobutylene succinic anhydride and ethanolamine. -~
An aqueous solution was prepared by mixing the ammonium
nitrate, CN (calcium nitrate), water and acetic acid. The
composition was heated to about 80C and was added to a
rapidly stirred blend of the oil and emulsifier. When
addition was complete stirring was continued until the
emulsion was uniform (about 60 seconds).
The ANFO (which comprised particulate ammonium nitrate on
which had been absorbed 6% by weight of fuel oil) was
blended with the emulsion and the gas stabilizing agent -
was then added with mixing, followed by the addition of
the gasser solution.
,
The water-in-oil emulsion of the explosive composition of
Example 1 prepared according to this process had a
Brookfield Viscosity of 30,000 cps.
The water-in-oil emulsion of the explosive composition of
Comparative Example A had a Brookfield Viscosity of 10,000
cps.
The compositions prepared according to the above process
were tested as follows~
The explosive (15 kg) is poured down a 4 m
high (150 mm diameter) artificial borehole
with a 200 mm diameter package at the bottom
containing water (15 kg). The package was
removed and excess water poured from the top.
The explosive was then primed with 400 g of
"ANZOMEX" (trade mark) primer.
: -
-18- 1331~
The co~po~ltlon o~ Ex-~pl- ~ ~ucc~ ully ~oton-Sod
on c~rry1n~ out th~ ~bov~ test but th~ co~poslt~on
of comp~r-tlvc Ex~mple A ~a11~a to deton~te.
ExamDles 2 and 3
~h~ Exploslv~s of Ex~mplY 2 ~ng 3 htv1ng the
compos1t10ns ~s ~hown ln T~ble 2 wor~ prep~r~d
~ccord1n~ to the ~ol10wlng proc~dur~
~ABLE 2
, :
E~a~pt~ 2 Ex~mple 3
lo Parts w~w P~rts ~rw
~mU 15 l on ~-QmDonent
Ammonlum n1tr~te
tchem1cally pure)40.66 40.66
~later 1~.16 10.1~
P~r~fr1n Sotl) 2.~5 2.55
~ PIBSA cmulslfl~1.53 l.S3
Lmmonlum nltr.ate ~rticl~
ANFO 45.0 45.0
VOI~lNG ~A~RIAL
"MICR08ALLOO~S"
4.0
:.
~ The PlBSA tmuls1fl~r w~s th- cond~ns~t10n product
of~MOBlLAD C207" ~MOBILAD 15 a tr~d- ~rk~ ~nd
oth~nolamlne 1n 1:1 mol~r r~tlo. MO~ILA~ C207 ls
25 poly1sobutylenc succ1nlc anhydrld~ ln a p~r~ffln
d11uent.
~ An ~qu~ous so1ut~on w~s pnepared by ~1x1no th~
: ~.mon1um nltr~t~ tind w~ter. Thc tompo~lt10n w~s
ho~te~ to about 80C ~nd w~s 4td~ to rapl~ly
30 Stlrrod bl~nd of the oll ~nd ~mul61f1~r. ~h~n
. ., .... ~, ~. , . ~ , .. ... .
- . . - . . ~ . .-. - ~ .. , . ~ ~ , ,
-19- ~33~
~ddlt~on ~s compl~tc ~elrr1no ~dS continu~t until
tho ~mulslon w~s unlform ~out 60 5~conds).
T~le AN~O (w~lch compr1sc~1 part1cul~t~ ~rnmontum
r,1Sr~o on wh1ch h~ D~en ~bsorbr~ 6% by welght Df
fuel o11 ) w~s bl~nCcd ~lth th~ ~ul5ton And th~ :
MICRo~ALbOONS ~er~ then ~ddtt ~1t~l ~1xlng. . ~ ~;
t~ w~Ser-tn-oll e~ulslon of th~ ~xplostv~ ~
compos1tlon o~ Ex~mpl~s 2 ~n~ 3 11~ d Brookf1eld -
costty ~ 34,S60 - 38560 cps.
The compo~1tlons of ~xamplo~ 2 ~nd 3 show~d 11ttl~
loss of AN from tho ~NFO ~h~n l~m~r~ 1n ~ t~r.
~h~ compostt10n of ~x-~nple 2 ocve ~8% of ~hock when : ::
detonated in water-containing bore-holes.
Ex~mDlc 4
The composition of example 2 was prepared and
che~tc~lly 9~sscd to ~ d~nsltY of 1.10 9Cm~3. ~ ;~
~h~ composltlon of ex4mple ~ ~vr 83~ of full energy
shock ~nd bubbl-) whtn ~ton~ d 1 n ~:
I~t~r-cont~ln1n~ bore-hol~s.
2 0 E x~
The composition of example 2 was prepared except that
. t~c p~r~ff1n o1i w~ repl~c~d ~1t~ ~urn~co o11.
T~o co~,pos1t10n of ex~mple 5 o~v~ 85-96~ of ful 1
en~roy ~-h~ck ~n~ bubbl~) when ~e~on~t~ld ln
25 h~t~r-cont~1n~no bor~-hol~s~200 ~ me~-r).
.. ,~ .
c = a ~ =
.,.;~. ~ ~ . ... ..... ; .. .
-20-
E~mDle 6 1331~
The composition of example 5 was prepared except that ~`
tho P~BSA ~muls1f10r ~5 roptdced W~th sorbltan
m~ no-o l e~te .
5 ~he osmpos1t1On o~ ex~mple 6 g~v~ 81-86k of ~ul l
en~r~y ~shock n~ bubbl~) wh-n d~ton~toJ ln
w~ter-c'ont~1n1ng bore-holes~200mm dl~meter). ~ :-
,. ~,~.
,~,, ~ . .
,
t
