1. business and industrial
2. energy
3. natural gas

ug. 20, i935.
H. A, BEEKHUIS, JR
2,011,704
PROCESS AND APPARATUS FOR THE VAPOR PHASE PRODUCTION OF' AMMONI
UM NITRATE I
r Filed May 7'; 195o
/esse/
4a
J’eparaî‘or
#à fer/apar
el
-49
3/
6
HERNAN ALBERT BEE/mul
BY Z
ATTQRNEY
Àug. 20, 1935.
,
2,011,704
H. A. BEEKHUIS, JR
PROCESS AND APPARATUS FOR THE VAPOR PHASE PRODUCTION OF AMMONI
Filed May '7, 1930
¿il
UM NITRATE
2 Sheets-Sheet 2
Z,0ii,74
l Patented Aug. 20, i935
2,011,704
PROCESS AND APPARATUS Foa THE VA
ron PHASE ritonUCTroN 0F AMMoNIUM
‘ NITRATE
à:
'
'
Y
,
Herman Albert Beekhuis, Jr., Syracuse, N. Y.,
'
assigner to Atmospheric Nitrogen Corporation,
New York, N. Y., a corporation of New York
Application May 7, 1930, Serial N0. 450,459 '
_
l
47 Claims.
with ammonium nitrite and the decomposition of
„ This invention relates to a process for the pro
the ñnely divided ammonium nitrate by reason of
duction of ammonium nitrate. More particu
Aiarly, this invention relates toa process for the high temperatures generated by the chemical
production of ammonium nitrate by reaction of ' reactions which take place.
It is an object of the present invention to pro-5 ammonia, nitrogentetroxide, water vapor and
' oxygen, whereby a solid ammonium nitrate prod
>
Y a
uct is directly obtained.
„
Y
I-t has heretofore been proposed to produce
n ` ammonium ¿nitrate
by
reaction
of
nitrogen
10 tetroxide (by which term is meant nitrogen oxide
correspondingto the` formula NO2 or N204 or
a mixture of NO2 and NzOrin any proportions),
water vapor, and oxygen with ammonia. In
'_ carrying out the process as previously proposed,
> 15 a gas containing nitrogen tetroxide, 'oxygen and
water vapor in desired proportions is mixed with
:a quantity of ammonia insuii’icient to react with
' the whole of the nitrogen >tetroxide in accordance
Ywith the equation,
A20
The solid ammonium nitrate thus y:formed is re
moved from Ythe residual gases in which it is sus
pended, and a further quantity of ammonia added
25 to react with the nitrogen tetroxide, water vapor
and oxygen of theV residual gases. By making
Vseveral additions of ammonia to the original
5
vide an economic process for the direct produc
tion of ammonium nitrate by which ñxed nitro
gen in the form of nitrogen oxides and ammonia
is‘eniciently transformed into ammonium nitrate.
Itis further, amongthe objects of this invention 10
to so modify and change the several steps of
prior processes for the direct production of am
monium nitrate as to result in marked improve
mentV in the operation ofhsuch processes; to pro
vide new conditions for carrying out the several 15
steps of those processes; and to so correlate those
steps and the conditions under which they are
operated as to provide a new and economic proc
ess for the direct production of ammonium ni
trate. Other objects ofthe invention Will in part 2_0
be obvious and will in part appear hereinafter,
I have discovered that ammonium nitrate may
be directly produced by the interaction inthe
gaseous phase of ammonia with nitrogen tetrox
ide, oxygen and water vapor in an eificient` and 25
_economic manner, and with reduced losses of
iixed` nitrogen. This I `have accomplished by an
nitrogen tetroxide gas with intermediate removal i improved coordination and correlation of the
of ammonium nitrate, the amount of nitrogen manner of introducing and admixing the Vam
3() tetroxide remaining is ‘too small to be suitable
for further treatment.
y
'
" Numerous din‘iculties are encountered in carry
ing out the process as described. The equation
given above'for the production of ammonium
Y, 35` nitrate represents butV one of several reactions
which'may take place simultaneously upon ad
mixing 'ammonia with the nitrogen tetroxide,
monia with the other components; the quantities 30
'of ammonia and water vapor utilized, and the
temperature at which the reaction takes place.
(It is to be understood that throughout the speci
iication and claims, when a quantity of gas is
mentionedreference is made to an amount of the 35
gas by volume). Thus the ammonia'is intro
duced into a gas containing the nitrogen tetrox
Water-vapor and oxygen. The nitrogen tetroxide ide, oxygen and water vapor and rapidly Aad
gas as commercially prepared contains a quantity ‘ mixed therewith by means of a specially devised
40 of nitric oxide (NO). In treating such va gas
with ammonia, nitrogen and water are formed by
`an oxidation of the ammonia by means of the
Vnitrogen oxides. vThis oxidationreaction may be
expressed by the equation,
-
l
mixing apparatus; they amount of ammoniais 40
less than about 0.3 times that required to neu
tralize all the nitrogen tetroxide; the amount of
water vapor is at least one part to each one part
of ammonia, and the temperature of the reaction
> is maintained within the range of below about 45
45
125° C. and above the dew point of water vapor in
It is apparent thatV the “fixed” nitrogen of the
' ammonia and nitrogen oxides converted into gas
i eous nitrogen represents an economic loss. VIt
50 has been found Vthat evenwhen the amount of
nitric oxide present Ywas restricted, serious losses
of ñxed nitrogen through its conversion into free
nitrogen
resulted.
-
Y
y
'
,
’
Other difficulties vencountered _were the con
55 taminatíon of the> ammonium Vnitrate product
the
gas mixture.
`
'
Y
`
l
'
`
I havev found that numerous factors influence
the eiiîciency of the reaction between ammonia,
nitrogentetroxide, water vapor, and oxygen to 50
form‘ammonia and that the commercial success
of a process employing that reaction is largely
determined by a propercontrol of the conditions
under which the reaction is carried out. With
out in any way limiting my invention thereto, but 55
f 2,011,704y
Y
.
,
'
as a possible'explanation for' the influence upon`r temperature 'ofy the reactionmixture entails cool
the eiiiciencyof the reaction' ofkvarious conditions ing the nitrogentetroxide gas prior to the vin- of operation as hereinaiter'setforth; I havev found ytroduction thereton of a limited `lquantity of am
thatthe data obtained for the reactions takingY
rplace upon mixing aninfionia,l nitrogen; tetroxide,
„An association .of the nitrogen tetroxide and
monia.
`
-
water vapor and' oxygen are in close-accord with Vwater Vapor as indicated >by vEquation II-above, l
an assiîinptionÍthat the following Yequations Vex
prior to its reaction with am'rnoniav would seem
press the chemical reactions taking place.
to be necessary for- high eiiìciency of rthe reaction
f» to yform ammonium nitrate., ¿ Thenitrogen tetroX
10
IV-ZI-IzNzOs-l-ZNHa-{Tl/ZOzä
"
j_k ~
Y
y
ide gas, prior _to introductionkof vammonia there 10
y. to, should contain aquantity of water vapor at
least equal tothe amount of ammonia'introduced
_
vis apparent that it` is desirable _to facilitate thereto: Ihave found that it is preferable for
Í15 ïIt
reaction IVV rather than-reaction'I'II -which re ¿economic operation -of the processrto regulate the
f
ì
'
»
2NH4NO3+H20+2NO2
sults in the> loss oi “nxed" 'nitrogen'.`r` Equation II»V. _',Y amount of water'vapor with relation tothe nitro- .
gentetroxide content of the gas and that a-suit->
able proportion is'between 0.5_ andv 2.5 or more
, ' conditions vwith Vrespect "t I 'the ratio
„
' represents `a'reversible -reaction, the equilibrium -
VA20
l
' » being 'dependent >lilßon temperature _and vconcen-V
parts ofV water’vapor to every 1 partY of NO2,
butin no _case should therebe a sufficient amount`
` . to form a liquid condensate'in» the gas withwhich 20
’_ Vthe ammonia _is -rn'ixed'- l't1 isv apparent, - there- "
ï tration 'of nitrogen `tetrf'nçide Vand water vapor. , l
foregfthat 'the'r amount [of excessy water vaporY
whichY may/„bez employed is dependent’upon the
IV'would appearvto Y ' temperature »of operation, andthe gases,V prior
215 f' Accordingly/,1'while‘Equation
indicate that~about'50% of the nitrogen tetroxide -'tothe introductionvof ammonia,` should ’be at a
>ì’nía gas may heeiîic’ientlyl utilized by lthe addition
Worf* Íammonia',> not all’.y of 'the' nitrogen ‘tetroxide
25
temperature‘abovefthe dew point'7 ofthe water
vapor contained therein. IfV the formation Yof a '
t iin the gas .wouldïbe combinedwith water vapor"y .liquid condensate» occurs,v corrosion ofthe ap
3'0»,V as HzNzOs andjvhenceflin*condition for »reactionW paratus in which the gas ¿is treated-results. Fur
thermore, I have found -that the presence of such
1 with ammonia. ` VF/’ithincrease inï‘temperaturea
V30
smaller proportion'. off- nitrogen , tetroXidel would l >a condensate in thefgases into ’which ammonia
vbefinì 'thev form .of vI-ïzNzOaand' hence a 'smaller , is'.v introduced results in anjundesirable moisture
proportion of ammonia 'may Aefñoiently;react with
content of the , ammonium nitrate i product',Y and
35 'thegas eWithV a »relatively dilute NOzjg‘as the - what is _still more serious, results-finl a contamina
l .Yproportion
ÍI have found
of HfiNzOsis
-that in .also
¿mixing
decreased.`
ammonia
4 _witha
Y
Y
` Y9% lNOz'gas containing,4.2% water‘vapor'ata
~
l
*Iï have further Vdiscovered that k'the concentrar Í'
- temperature'o‘f’about 50° C., the eñiciencyzof the
{reaction> rapidly'decreasedwhen they ammoniaY
was v added in4 .aA
tion of- the l’prccluctfwith ammonium nitrite and
other impurities.
quantity'more ‘I than about 0.3,`
’ times'the amount of nitrogen tetroXide contained.v
tion-sof the nitrogen Yte'troxi'de in the reaction
mixtureof gases plays an important» role inthe
efâciency lof VYthe reaction- to form ammonium
nitrate. ' Equation II'above may serve toeXpIain
in-Vlthe gas. „On Vthelother hand;v 'l1r hayeffound thisk discovery.„A "As has’already been stated, the
Y"that-Vin mixing lammoniak with/largas containing YVlresults“obtained by this invention indicate'vthat
about `6,11% or less of nitrogen tetroxiderit is lad-Y the-ïreaction between nitrogenY tetroxide, water
isable that the .amount of` ammonia added v.he ' vlvapor, oxygen, andarnn'ionia takes yplaceV in two
less than about 0.25 times'. the amountîrequireïdïto - .stagesçy‘ ñrstg'thewforrnation: Yof _the compound
wneutralizeall the-.nitrogen tetroxide contained in` - HzNgOs and the reactionof àarnmoniagwith this '
n
45
product. The formationof HzNzOswould'appear
K‘ rEhe reaction >of ammonia with nitrogen tetroX- ' ' to; occur >as the result Yor" the reversible reaction
represented by Equation îII- abover andthe amount 50
ide,- waterv vapor and.` oxygen, `liberates >a vcon
thegas.
.
`
-
«
Siderable amount of KVheat which," by elevatingthe
Y of H2N2O5 present in a mixture ot gasesinay be o.
_ temperaturey of the reacting gases, deleteriously represented by the equilibrium~ 'equation for this
`iniiuencesthe efliciency of the reaction. >`Ihave
Yfound thatïthe reaction mixture should‘be main
tained at a temperature below about '125°- C. inf
' order to prevent an excessive loss of ñxednitroe"
‘ gen;
I v'have »found furthen' thatlit. is preferable ’
This interpretation or" the chernistrylof the'process '
lserves to ,explain irnyA discovery that thenitrogen
vv'to control the temperature by introducing vthe Y 'tetroxide and water' vapor should' not» lbe tooY
60 ammoniaV into a gas contaíningnritrogen tetroxide
at a temperature sufñcientlypbelow‘lZâ? C.’ that
A ‘- by: the" intr'oductioniof a limited amount of arn- _
highly 'diluted' in thegaseous lreaction mixture
since van excessive?dilution> not only »requires the
treatment of unnecessarily large amounts ci gas
monia insuñìcient heat' »_is'liberated 'by lthe 4reac ybut >_exercises a deleterious infini-:nce upon. the
tion to' elevate the temperature of.: the reactionA j'r'eaetion to forni ammonium‘ïi'iitratebV I rhave
"165 mixture _abovegabout v12,5" C.ff,»l_3y,-.tlf1'V _i correlating
.Qf found that itis preferahle'to adinix a <_zoncentratedv
,the ftemperatureY of the 4nitrogen?f-tetroxide -gas _ammonia gas with the' nitrogenlftetronide gas, »
and Ythe amount of ammonia` added >thereto _even ‘.'vavoiding ¿thereltjyfanr unnecessary dilution `oi they
aëlocal excessive' heating of the reactionJIniXtureï " reactionïmixture "of gases, _Vs/’hile
excess of
is preventedflt‘is-fpossible, howeverçïto obtainl oXyg’cn'o-Ver -the Vamount"required vfor theA re- .
»satisfactory resultsglby providing highly- eiîicientr action to form :an'mioniunV nitrate shouldj `be
vmeans for "removing thefheat , of f the reaction; `
y 'Whenl‘a’ vnitrogen"tetroxidegas ,at> an elevatedv
' temperature'is to bíepemployed‘ in the production ,
present,fany’«undulylargeexcess is to >be avoided
because of the -dilutionoic thenitrogentetroxide
thereby. >I have found itpreferable@therefore,`
Í‘of! ammonium nitrate.> in `vaccordance .withmy in-j ` tto-limit rthe amount of oxygenin lthe reaction
v-Ventionggthe preferred method , of . controlling the4 . rmixture to an amount/:not greaterith'an about l0 %
_
:of> the total volume of the gas with which the
ammonia is admixed.
mixing., of the ammonia with the nitrogen
tetroxide, water vapor and oxygen, is necessary
>for `«their erlicient conversion >into ammonium
nitrate. The desirability of rapid mixing is in
dicated by a comparison of »Equations III' and IV
above.` The reactions represented by these equa
tions take'place with great rapidity so that if> in
the'mixturey oi >gases there be la localized excess
of ammonia, the `reaction of> Equation ‘III result
Y_ing-in a loss of fixed nitrogen takes place> where
‘the excess of‘arnmonia exists even ior'a‘very
short period of time.
' Y! Furthermore, I have found that it is »important
that the ammonia should be introducedv into a
gas containing nitrogen tetroxide, water vapor
i and oxygen, and that the nitrogenoxides should
beY relatively completely .oxidized to nitrogen
>tetroxide prior to the introduction' of ammonia,
~
gen mayfbe added to the gases passing through
pipe 3.
.
ï I’have discovered further, that a very rapid
lo
3
2,011,704
-
From pipe 3 the gases are passed into the bot
tom of a gas cooler ¿i wherein they mingle with
residual gas from a pipe 2S and are intimately
contacted with an aqueous medium having a pree
determined composition and temperature, pref
erably a solution of nitric acid, introduced into
the top of the cooler from a pipe 6. `Cooler ¿i pref
erably contains va packing material which ensures 10
intimate> Contact between the gases passed
`through the cooler and the nitric acid solution in
troduced therein. The nitric acid after contacting with the gas is withdrawn from thevbot
tom of cooler ¿l through a pipe 5, and is circulat~
ed through a cooler l in indirect contact with a
cooling medium such as water, back to the top
of cooler li for renewed contact with gas from
pipe 3. "I‘he cooling water is introduced into
cooler 'I from a pipeß and withdrawn therefrom
through a pipe 9. By its contact in cooler d with
' for examplerthe state oí oxidation of the nitrogen
cool dilute nitric acid, the gas Afrom pipe 3 is
’oxide 4gasis preferably such that 80% or more
Ylilly invention-accordingly comprises the several
cooled to a desired temperature and its water Va
por content is adjusted either by taking up from
the nitric acid a quantity of water corresponding
steps and the relation of‘one or more of such steps
with respect to each of theothers and the appa
to saturation ci the gas under the conditions of
temperature and concentration of the acid, or
ofq'the nitrogen oxides are present as NO2.
ratus embodying features of construction, combi
ir" the gas from pipe 3 contains an excess of water
and the scope oi the invention will be indicated
vapor above that corresponding .to saturation in
contact with the nitric acid in cooler ß, the ex~
cess water vapor condenses out of the gas. The
nitric acid solution likewise may absorb nitrogen
in the claims.
oxides from the gas which react to form nitric Y
« nations oi elements and arrangement of parts
30 which are adapted to eiîect such steps., all as
exemplified in the following detailed disclosure,
. ’
For a` fuller understanding of the nature and
objects of my invention, reference should be 'had
to ï`the following detailed description taken in
connection with the accompanying drawings, in
which:
either a portion of the acid may be withdrawn
during'its circulation or a quantity of water added
thereto as may be desirable.
’
, ~ Fig. 1 is a diagrammatic»representation of the
40 process of this invention as carried outY in one
type 'of apparatus;
Y»
f
Fig. 2*»is an elevation, _in cross-section, of the
reaction vessels oi Fig. l; and "
Fig. 3 >is a _diagrammatic representation of the
process of this invention as carried out in a dif
vferent type of apparatus from that illustrated
in'Fig. 1.
acid and in such a casein order to maintain a`
constant composition of cooling acid in cooler ¿l 35
i
-
Y Referring` now to Fig. l, a Vnitrogen oxide gas
such as is obtained from the heat exchangers and
‘coolers of an ammonia oxidation system, which
contains oxygen anda relatively large amount
i
The cooling of the nitrogen tetroxide gas may
be accomplished in other manners than that de-V 40
scribed, for example by passing the gas in in
direct heat exchange with a cooling medium. By
employing direct cooling with aqueous nitric acid,
however, simultaneously with the cooling of the
gas its waterl vapor content is adjusted by con
trolling'the concentration of the acid and the
temperature of cooling. Furthermore, I have
discovered that an'acid of proper concentration
does not remove from a gas 'contacted therewith
finely divided particles of solid ammonium ni 50
trate. The residual gas introduced intoA cooler 4
otwater vapor, is passed through a pipe `l into
an oxidation chamber 2 where the nitrogen oxides
are oxidized to nitrogen tetroxide, and the re
carries with it a small amount of suspended solid
ammonium nitrate. This ammonium nitrate not
only does not interfere with the cooling of the
sulting gas containing nitrogen tetroxide, water
gases, as it would in case the heat transfer were
Vvapor and oxygen, leaves chamber' 2 through a
through metal surfaces upon which the am
monium nitrate would deposit, but also the am
monium nitrate in large part passes with the
gases through the cooler and may be recovered
along with additional ammonium nitrate subse 60
quently formed and recovered as described below.
The gas passed through cooler ¿l is withdrawn
through a pipe lû and passed to a, reaction vessel
I i where itis admixed with ammonia from a pipe
i2. The amount of ammonia vintroduced into
pipe'3. It is apparentthat a nitrogen oxide gas
from a source other than an ammonia oxidation
system, may be’passed into chamber 2 forv treat
ment therein, or`if a gas of the proper composi
tion is available, the treatment in chamber _2 may
be omitted and the gas passeddirectly through
pipe 3 for use as hereinafter described. ' The gas
Vpassed through pipe 3 preferably contains about
80% of its contenter" nitrogen oxides as nitrogen
tetroxide. It shouldalso contain a quantity of
oxygen sufficient for the product-ion oi ammonium
nitrate in accordance with Equation I above. It
Vthe gas passed into chamber 2 contains in
sufficient oxygen for the oxidation of the nitrogen
oxides, additional oxygen may be admixed there
reaction vessel i i is proportioned with respect to
the amount of nitrogen tetroxide introduced
thereto such that the amount of ammonia in the
reaction mixture of gases is less than about 0,3
times, and for example, employing a gas contain
ing between 5 and 6% or" nitrogen tetroxide, is
. with prior to their passage into chamber 'if and ii f preferably between about 0.10 and 0.25 times the
required to make up -for any deficiency. in the amount required to neutralize all of the nitrogen
amount of .free oxygen with respect to the desired tetroxide. The ammonia, nitrogen tetroxide,
oxygen and water Vapor react to form ammonium
proportion ,of oxygen and nitrogen tetroxide, oxy
7 2,011,704
Ä nitrate `vvhichis ,suspended as a finelyl divided> _, of nitrogen tetrozàide gas, vpassing «through reac
1' , solid inthe gases leavingreaction vessel Hl.: As
tion chamberl i6. The ammonia is introduced as
a* result 'of Ythis reactiongto form ammonium rm - a restricted stream flowing through the orifice in
trate,V considerable lquantities. Vof heat .arevf'liber plate 9S into the' turbulentlyl flowing stream of>
'ated'.u AThe temperatureV attained bythe reacting nitrogenitetroxide gas, rand isy rapidly and thor
gases asia result of this liberation ofheatshould oughlyfadmixed; Withv Vthe nitrogen tetroxide,
be limited -to,aftemperatureflmelovv'ìaloout 125;"v C. Y 4roxygen' and Water Vapor, with Which'it reactsto
As 'notedfabovav the 'temperature of they reacting
form rammonium;nitrate:
-
l lReferringincvv to Fig. 1, the gases leaving Vre#>
.t`so
1e >correlating
' course
gases
125° C.is“of
bypreferably
, reaction-below
maintained
>the degree
this;throughout
vtempe_rzfiture
of coolingïof
Í the
of f action vessel ‘ll carry with them the'ammonium !Qf
nitrateproo'lucedv therein and pass through a pipe
>,the ,nitrogenr tetroxide ` gas in `gasico’olery à' and’ the, < yttl-¿to a separator 25 wherein the solid ammonium y ï »i
- amount »of ammonia admised 'therewith in the i nitrateisseparated Vfrom the gas stream and re-`
’_
reaction »vessel that. insufficient heat> is liberatedl l movedthrough a pipe 26. Separator 25 may be of v
15.
4by the reaction to yraise the ,temperature of the Y, rany desired type such as ra centrifugal, lbaiîle or 15 l
‘electrostatic’separatori The Vgases from which the
f
' " L cooled gases above 125° 'C._ It is important, hoWf Y
ever, that the nitrogen tetroxidegas belnotcooled
in gas coo'ier ¿l to sucha lowltemperature that the
ammonium' nitrate has been in 'large part re-'
Vrno‘vîed‘are passed through a pipe 2l' and inzpartv
' Watervapor content,- which is limitedrfby the tem- I ’are returned through a pipe 28 to gas cooler f3 for
perature of thegas, Wouldfbeless thanabout- 1 « . renewed- treatment therein and subsequent re* 29
.i part of Water vapor for every konefpart'ofy ammo
action with ammonia in reaction vessel t i to form
nia subsequently added thereto. :It has.` been additional-quantities of vammonium nitrate.r The Y
foundthat a;V proces-_s maybe rs'atisfactorily‘ oper- K recirculation of the ,'gasesífrom _separator V_25' is
` ated
65% when
nitrogentetroxide
a
containing
in not
passing
more«throughy
than about
gas induced by a fan 25. '
, VA portion ofthe residual gas containing nitrogen ’
cooler, ¿iis cooled to. a temperature of about 406 . tetrcxi'degoxygen and Water vapor from separator
25.
’ C. and the reactinggases .in reactionf vessel H ` . 25 passing through pipes 2ï and28 ris bledV fromV
are l maintained ’l throughout ther coursel of the y,re 'Y thecirculatory system above ydescribed and passed
action at temperatures between about ¿l0? C. and- through 'ai pipeß? >to a second circulatory system
125° C. >Undersuch conditions,> by employingin wherein.ammoniumnitrate is rproduced there 30Y
gasïcoole‘r'd an ‘aqueous solution yof nitric >acid `Vfrom
inamanncr similarftozthetreatment of the
containing :about , 50 %‘VY HNOa ’at aboutv 40° 'C.,„the v 'nitrogen ¿tetroxide oxygen andgwaterV Vapor gasV
1 nitrogen tetroxidegas may be cooled ftofa-nrap ' from pipe' 3. g Thisseoond circulatory systemrcom
propriateternperature and its waterrvapor'fcon- ». prises aifgas coolerl 39,'1cooler Sllfreaction Vessels
oo DI
and to anda separator 4l, which may beof 3,5;
the sanieitype as the: corresponding portions of
the acid orgiving upto theaeid'any undesirabie the ,circulatoryYsystemA above described. In gas
excessïof Water vapor Whichgit may. contain. If ~ .cooler >3l the gas from pipe .êtl’is cooled and itsY
any aqueous medium other than arnitricacidso- ~. Water vapor. content: adjusted by direct contact
>lution isemployed inthe cooling of the gas, it is . with dilute nitric acidpassed into cooler 3i from
apparent thatthe_moisturel content Íof‘ the gasv a pipe 32'. After contactewith theìgas the nitricl
Vmay likewise be regulated by controlling the Ytem ‘ acid is Withdrawnvfrom cooler Sifthrough a pipe
' v tent automatically regulatedA either bythe gas>
~ taking up.y the proper ramount of," moisture >from
perature V'and concentration» of* such A@aqueous 1 33, passed through a coolerâë, Where it is cooledV
medium.
l
'
'
~~
'
by means of cooling Water, andisrecirculated toV
‘ Itis of importancethat theammonia be intro- ‘
. ducedyin reaction ‘Í vesself! i, into the ' nitrogen '
cooler v3i through pipe’32. As inthe ease of the
gas iii-cooler@1 it is preferred Ato'cool the gas'inA
tetroxide gas containingfoxygen and Watervapor g» ,coolerfäl’ to a, temperaturev of’ab'out 40°C; -The
and be quickly and thoroughly admix'edWithtl'n‘sV thus cooledrgas is passed by Way ofV pipes-¿35,î3ß,
~ gas. VIn Fig. 2 is‘shownone type ofgreaction'vessel 37 and »38' through reaction vessels Vsgjand' 45,
which has been found toY be suitable/forlcarryingV` Y Whereinrthey are treated with ammonia to pro
out the reaction.v >In, thatvfigure, the numeral »E3
Y, designates a cas'ing‘provided'with closur'esléi and
l5,«whichtogether, define a mixing and reaction
` »chamber l5.` A ypipe lf'lr„which corresponds to
Clt,
duce ammonium nitrater and thence to separator
Mwhere the ammonium nitrate is removed trom
the residualc unreactedf gas. As yshoum in the
drawings, the'gas from Yreaction vessel 39 passes
'Ul pipe l0 'of Figgfl», opens through closure v§55 into f vthrough af rest chamber` f32íbefore entering reac
chamberïlâ and serves for the introduction into tiongvessel 4Q. Fromseparator el the ammonium
chamberldof'the nitrogen tetroxide; oxygen and nitrate produced inereaction Vessels 39 and ¿il? ‘is
Water'vapor»gas.¿_A second-_pipe i8 lserving removed through a pipeV ¿t3 and residualv gas :re-V
(it)y
furthe introduction of ammonia into'chamber It,
.passes through _closure l5 andterminatesin are--v
turned throughi'pipes À¿lli and‘45 to cooler Bimby
means >of a fank 4E'. A'portion of the VgasV is dis
stricted oriñceformed inaplate i9 seated on'the charged from theV system through a'pipe 4'! and'
may_'if desired. `be treated to recover the'residual
" .oppositehendof _casing lälapipe 25 which opens Y' relativelyvsmall amount' of 'nitrogenoxìdes con
‘endrof pipe ,I8 Withinïchamber I6.r Adjacent the
througheasing I3'into1chamber l5 Yis provided
for removing thefunreacted .gasesjand the reaction
products >from chambery! 6, A rotatable shaft l2l
has .__one endl seated‘in a bearing 22 carried by
’closure l5 and extends through closure M by’way
ofrargas-tightioint to afpoint Without the 'reacf
tion vessel; Means not shown in Fig.' 2.are pro
' tained therein or' otherwise disposed of. -
~-The heat liberated byv thegforrnation ofv am’
moniumy nitrate in reaction vessels 353 and Ai!) is
removedlfromthe -gas by dissipation during >pas
sage from thesevessels to gas cooler 3i and in
gas cooler 3| by contact With'cooled dilute nitric
acid.
Theïcontentl ¿of water Vapor, -'nitrogen '_
vided for rapidly rotating shz'iftliï.y Shaftf‘?! tetroxide vandioxygen of the residualgasïis ad
’within reaction chamber lßcarries av grid 23 which2 justed .in.~_-coole"ry 3l by direct contactofdilute „
isV attachedto theshaft for rotation therewith.
By rapidly` rotating shaft 2! andl grid 23; ajtur- _ nitric acidvl therewith andby kadmixture with the
‘ hulence is AI_nechanically.impartedto _the stream
gas from jpipe 3.9.» The thus treated >gas inre
action Vessel> 39 is'mixedr in »reaction vessels 39
50
Y
~
5,
l2,011,704
pure ammonia gas. The gas leaving `reaction
spectively. In each reaction vesselan amount of, vessel ||, after .separation of the ammonium ni
ammonia is admixed with the nitrogen tetroxide trate in separator 25, is divided and four-fifths
gas’ suchthat in each of the reaction vessels, the may be returned to gas cooler il and the remain- i
amount oi' ammonia. in the reaction mixture is ingone-ñìth passed to gas cooler 3|.
The second circulatory system comprises gas f
lessV than about 0.3 times and is preferably less
cooler
Si, reaction vessels 3e and 40, rest cham- f
than about 0.25 .times theV amount required to
neutralize‘all of the nitrogen` tetroxide therein. ber 42, separator 4| and ian 46. In this system,
Theuse of two reaction vessels, 39 andgíiii, in gas entering the gas cooler from pipe 36 may be
and is with ammonia, frompip'e's .as and 49 lre
admixed with about i’our times its volume of re
10 series is advantageous when the nitrogen tetrox- p sidual gas from pipe ¿l5 and the gas mixture cooled
ide concentration in the gas is low, for example
about 2% NO2. In such case the temperature o1“ to about 40° C. by direct contact with dilute nitric
the gases leaving `reaction vessel 39 is suiiiciently ' acid. The gas leaving cooler 3| may be admixed
low `that a further quantity oi ammonia may be with about 0.004 times its volume ofammonia
from pipe 48. Ammonium nitrate is formed and, 15
15 added in reaction vessel 40 and a temperature of
together with’the residual gas, passes through
»125° C. not exceeded. Thus, there may beV in
troduced into vessel 3e an amount of ammonia rest chamber ¿lf2 to reaction vessel' 60. The gas
about .25 Vtimes the amount required to neu~ passed to reaction vessel de may have a tempera
`tralize all of the nitrogenA tetroxide passed into -ture of about 70° C. and is admixed with about
0.003 times its volume of 'ammonia from pipe 49.
20 the vessel and a like amount of ammonia maybe
lintroduced into vessel 40., Intermediate the two Additional ammonium nitrate is formed and the
reaction vessels 39 and @.0 the gas'containing
temperature of the gas leaving reaction vessel "|50
ammonium nitrate formed in reaction vessel 39
passes through rest chamber ¿i2 where it is main
cent condition to _permit further oxidation of
lower-oxides oi`_ nitrogen contained in the gas
rises to about 95° C. The ammonium nitrate pro
duced in reaction vesselsSB and d@ is removed in
separator ti l. >The residual gas contains about 1%
NO2. About four-fifths of the residual gas is re
circulated to the gas cooler 3|, while about one
and the readjustment of the equilibrium between
Íifth is discharged from pipe 4I.
the nitrogen _tetroxide and water vapor and
I-I2N205 formed by their combination. If de
sired, however, the gas from the reaction vessel
33 may he passed directly to reaction vessel '40.
In Fig. 3, there is diagrammatically illustrated a
process for the production of ammonium nitrate
in accordance with this invention in which the
» The process for the production of ammonium
recirculation of the residual unreacted gases.
The apparatus of this figure consists or" `two simi
tained for a periodof time in a relatively quies
35 _
nitrateas carried out in the apparatus diagram-`
matically illustrated >in Fig. 1 comprises the
treatment of a gas containing nitrogen tetroxide,
>oxygen and water vapor in two circulatory sys
tems. `In theiirst of these systems, which com
prises gas cooler e, reaction vessel il, separator
25 Vand ian‘îä, during the circulation of the gas,
-
successive additions of ammonia are admixed
' therewith in reaction vessel ii to produce am->
xmonium nitrate which .is separated >from the
40,
residual gas in separator 25; The heat liberated
by `the reaction in vessel il is removed from the
circulatory system by dissipation ’to the sur
rounding air in the travel of gases from there
action vessel back to the gas cooler and by con
tacting'the gases in cooler 4 with the cool dilute
nitric acid passing therethrough.
The nitrogen -
‘ A
i
3o
nitrogen tetroxide gas is treatedinseries without
lar groups, each group comprising a gas cooler |04
or .,iäi, a nitric acidscooler |01 or i3d, reaction
vessel iii or i559, and separator |25 or |là| which
may be of the same type as the corresponding por
tions ci the apparatus of Fig. l. Although in
Fig. 3 an apparatus is'illustrated consisting or" 40
two groups, itis to be understood‘that one or more
additicnalxgroups may `loe. employed as may lbe
desired.
.
..
'
»
'
-
.
7.
In employing the apparatus'of Fig. 3, a gas cor
responding, for example, to the gas passed togas 4.5r
>cooler fi of the apparatusci Fig. l is passed
through pipe |03 to a gas cooler |04 where Vit is
cooled by direct contact with dilute nitric acid
from pipe |05. After contact with the gas the
dilute nitric acid is passed through pipe |06 to 50
cooler lüï where it is cooled by means of cooling
tetroxide, oxygen 'and water vapor content of
the recirculating gases is adjusted by treatment water circulated therethrough by way'of pipes
lwith `the dilute nitric acid and by addition of íiiSand. H39 and returned through pipe |05 to the
fresh gases from pipe 3 and the recirculatingv gas cooler. The cooled nitrogen tetroxide gas con- .
' gases then pass to reaction vessel || for .admix
ture therewith of ammonia. ï
co
.
The following conditions are illustrative» of
one embodiment of my invention, but it is to
be understood that the invention is in no’ wise
limited to the conditions specifically set forth.
YA gas‘irom the heat exchangers of an ammonia
oxidation system containing about 9% nitrogen
oxides calculated as NO2, about 2 to 4% water
yapor and about l to 5% oxygen may betreated
in voxidation chamber` 2f. to oxidize the lower
>oxides of nitrogen to -nitrogen'jtetroxide and
thence passed at a temperature of,` for example,
about 106° C., to gas cooler t where it is cooled
taining oxygen and Water vapor passes from gas
cooler. iilâ through a pipe HE] to reaction vessel
iii where it is admixed with ammonia from a
pipe` |52. The ammonium nitrate and residual
gases pass through a pipe |24 to separator |25 in
which the ammonium nitrate is removed from the
gas and is withdrawn through a pipe |26. The
residual gas passes through a pipe |334 to gas
Vcooler- i3! of the succeeding group for treatment
in the apparatus of that group for theproduction
of additional ammonium nitrate. In gas cooler
i3! the residual gases‘are cooled and their water
vapor content adjusted by direct contact with
dilute nitric acid from pipe |32. 'I‘he dilute nitric
acid, after contact with the gas, is passed through
to an appropriate temperature by direct contact
with dilute nitric acid. The‘gas passed into the
cooler may be admixed therein with about four ` pipe |33 to cooler |34 where it is cooled by means
timesyits volume of residual gas from pipe 28. of» cooling water and recirculated through pipe
The gas leaving thecooler through pipe` l0 Amay §32 back to gas cooler |3|. The thus treated
contain 'about 5% to 6% NO2. 2 to 4% H2O and residual gas passes through pipe |35 toreaction
l to 5% O2. In >reaction vessel || it is admixed vessel §39 where it is admixed with ammonia
with about 0.0l'times its volume of substantially from pipe |48. The ammonium nitrate and unre
55
actedl
pass through pipegi 38 'ïtofl'separator ^ v,which comprises :maintaining thetempîerature "of
I ¿il _where " theuammoniumi. nitrate;`v is¿ . separated
.v said gases ` throughoutr
1 out and withdrawn 'through ra ‘pipellliàr yThe Are
'4. In the process of producingiammonium ni; Y
trateby reactionof ammonia, water vapor, ni- f
' trogen tetroxid'e` and'oxygen, thatlimprovement
_ ‘ nitrogeng'oxides or ¿disposed of in: -any,r desired
A'manner..;.
>
V-
`
'
-'
the course `of ¿the reaction ï
lbelow about Y125" C.; '
sidual gas is discharged'throu'gh apipeÍ ,l‘álfor
>'treatment to recover itsremaining ìcontentï‘of
-~
which., comprises mixing `said Vgases ‘and`V main,- f
»The production of Vammonium nitrate; in ac'
'taining 'theV temperature of'. saidV mixed `gases
throughout the course ofr the reaction below
.about .125° C1 and above the dew point oi the Vwa
V l 1‘ cordance Withthismodification ofV my invention, j
10. comprises forming in each lof reactionvessels i l l
and’lßiia mixture oi gases containing-,nitrogen
ter vapor in said mixture;
' itetroxide,foxygen„water'vapor andammonia in
'
1
-
.
`:5..In the process v,of’producing ammonium yni-f t
` such proportions that:r the amount of ammonia'ï Vtrate. by reaction @_i-ammonia, water vapor, ni
.f isilessethan about «033 ztimes the amount required
trogenftetroxide andoxygen, that improvement
toneutralize allcthe-` nitrogen', tetroxide in .the Íy .which'comprises,maintaining said gases through
admixture..r .The“nitrogenk oxide >gases passed to ' out the course of the reaction at temperatures be-V
the reaction vessels are cooledlfin‘gascooler we
- tween about 40? C. to 125° C. Y
or; |735 Vto a temperature .which *may be 4about,
`40°*> C'Lfwhereb'yftthe .temperatureY of. the gases’ in-
l.
‘
‘-
~
f6. The process/of producing ammonium nitrate
t whiciigcomprises admixing ammonia with a gas,
reaction-'vessels y i I i .anfdr l39~is not- increased tok v
containing nitrogen tetroxide, oxygen and water
abovejabout 125° f C; ,by the lneat liberated» by the t , Vapor',jiimiting the quantity of said ammonia to
>reaction to 'form ammonium’„.nitrate.l In both ' an amount‘insuñicient. to neutralize all the ni»
Vofithe.gas coolers'the-nitrogentetroxide andv oxy- ' "
trogen tetroxide contained in'said gas, and maintaining'said mixture throughout` the course of the
» gen- VVgasA` is> simultaneously vcooled ,and »its >water
Vapor i‘content :adjusted »byf direct- Contact` with 4' reaction at a temperature below 'about 125° C.
25
f '7. The 'processoi producing> ammonium ni
«trate which comprisesadmixing ammonia withV
the production" of ammonium4 nitrate ¿embodying a gas containing’nitrogentetroxide, oxygen and
this invention, ¿comprise radmixing :in reaction water vapor, limiting thequantity'of said ammo
aqueous
3 ' The above
nitricY
vdescribed
acid.
`examples
,
’ of processesf‘or
.
vesselsizigäâ and ¿wor i li and |39 a-pluralityof nia to an amount insufficient to neutralize" all the ` 3o"
successive; additionsjof ammonia with a gasfcon' ` nitrogen
'tetroxide v contained ’in saidA gas, and
taining. nitrogen? tetroxide, fox'ygen' .and „'»water 1 maintaining
said`inixture throughout the >ci’iurse
vapor. 'The nitrogen'tetroàddegas is cooled'` in lof; the reaction'at'a'/ temperature above' the dew
'gascoolerslàv 3i," itâ orißl .prior vto the intro' 'pointV of the water ïva'por in the mixture and be
duction oiäarnmonia, and r»thequantity oieachÍ low about12r5° C* Y t
Y
‘Y
es"
8. The process jf producing 'ammonium nitrate ’
suiiicient to"completely.,neutralize'..the nitrogen which comprises admiring ammonia withïa gras
tetroxideingthe gas’ with which itïis-adrnixed
addition of .ammonia is limited »totanamount in- ~
containing'nítrog'en rtetroxide, Yoxygen and water
which, Vin the particular processesdescribed, is
preferably/between.aboutit.;,and 0.25 times that
vapor and limitingfthe quantity yofthe ammonia
to ran amount such that the heatïliberated by 40
reaction of the'v ammonialwith said gas is insum- ,
»cient to heat: the. reaction ‘mix turej to Ya tempera'f.
vreduiredgto `:neutralize allÍofftheqfnitrogen tet
roxideadrnixed therewith. VThe ¿ .temperatureof
« kthe reaction mixture vin each"Y oiî'ívjessel's i 4;'39, di?,
tureabovevabóut `125" C.
lil> and f i39isf maintained below „about 125°. C..
4.5„
«
,
l
Y
n
_
.
~ 9; Theprocess of producing' ammonium nitrate
which `comprises introducing ammonia into a
t cooled'gas mixture containing nitrogen tetroxide,
a A`Sinceleertairi vchanges; in` carryingl >out the '
oxygen and >water» vapor and correlating the‘tem
perature to.v whichsaid mixture istcooled and the
by correlating'»thedegreefof coolingfof the nitro`-Ã
v
,
,
.
Y gen,..tetroxidey Agas :andthe amount'of ammonia'V
ï admixed with the-cooled‘gas.VY
p
:
Y
rabove processes fand. intîhefconstructions set
.à forthwlfiich.embodyy the invention maybe made , quantity offam'monia added _thereto whereby the Á
i reaction" mixtureV is ¿heated toV r,a temperature
1 without departing'fromiits'scopa Vit is intendedv below about 125? C; gby Vthefhrçzfat liberated byA 50
- .thatallïmatter‘contained'in the above description reaction offäsaidßammonia with' the gas'mixture.
, or »shown inthe accompanying ldrawings shall
t
10. The process Vof producingY ammonium ni
' , be _interpretedas 'illustrative and not in alimit
ing sense.` ‘ "
v
.
Iclaim:
f~
`
.t trate twhich comprises introducing ammonia rinto .
a cooled gasv mixture containing nitrogen tetrox
D
» .1. 'In the-processofproducing ammonium ni-l
ide, ycnrygenxjan'd »water vaporyrcorrelating theV
,temperature to whichjsaid mixture is j cooled and
troge'n ,tetroxide and oxygen, that'i'mproyement the quantity of ammonia added thereto whereby
Athe reaction mixture is heated ¿to a temperature
1607,.V which ‘comprises forming'. a mixture of said gases
belowf about 125° C,y by the heat' liberated by
in proportions such that the amount of ammo-v` reaction
of said ammonia with the gas mixture,
nia inisaidmixture isless than about 0.3V times separating vammonii‘un ‘ nitrate .thus produced
rthe.a‘rnc'iuntîrequired to neutralize all'of thehi-` fro'rn'the
residual gas; cooling the Wresidual gas
.
trogen tetroinde therein.> »j
,
Y
'
‘
trate by reaction of ammonia-.watervapor,y ni- t
'
l
"65
-
,
adjusting its contentfïor" lnitrogen tetroxide,
A2..“_I'n theproce'ss‘of` produoingfammonium ni*-Y fand
oxygen'gand Wateri vapor to produceiajgas >mix
ture` having-’substantially the same composition es
n
.
. trate ‘byf reaction ofr'ammonia, watervapor, ni
trogen'tetroxide vand oxygengfthat improvementV
' , which comprises forming a mixture of-said gases
in proportions such that theamount'of Vammo
fasthe laforesaid cooled gas mixture andemploy
ing ,the resulting cooled gas mixtureriorßthe pro
f' duction -' of V‘ammonium Vnitrate inv Y the». manner
nia vin‘said mixture is yless than1abóut0'~25 timesrk ., »hereinbefore described;Y f
~
r1175
60
trogen
the kamount
tetroxide'therein.
required-„to -ìfleutraliae'all'of
.
'
"the“ ni-l
if " f
11; The_„process of producing ammonium` ni
ytrate which comprises introducing ammonia into- '
1,13.v In the.ïprocessofproducingammonium ni»V v a gas mixture containing nitrogen tetroxide, oxy
l trate by reaction of ammonia,.watery vapor, ni--~
gen 'and- water vaportat atemperature of labout
f trogen-î tetroxideand oxygen, that improvement 40° C., limiting rthe quantity of fthe ammonia' to
7
2,01 1,704
’an-amount such that the >heat liberated by reac
tion of the ammonia with said gas mixture is
insufficient to heat the reaction mixture to a>
temperature above about 125° C., separating
from the residual gas, and cooling the gas prior
to addition of ammonia thereto to a predeter
ined temperature. whereby the heat liberated
by the reaction of the ammonia with the thus
ammonium nitrate thus produced from the resid- - cooled gas is insuñîcient to heat the reaction
mixture to a temperature above about 125° C.
' ual gas, adjusting the content of nitrogen tetrox
18. The process of producing ammonium ni
ide, oxygen and water vapor of theresidual gas
' and» removing heat therefrom to produce a gas
UX
trate whichcomprises introducing successive ad
ditions of ammonia into a gas containing nitro
gen tetroxide,- oxygen and water vapor, limiting
the quantity of each addition ofv ammonia to an
amount less than about 0.25 times that required
' to completely neutralize all of the nitrogen tet
manner hereinbefore described.
~
roxide in the gas into which said addition is intro
I , 12. lIn the processor producing ammonium ni
duced, separating ammonium nitrate formed from
trate by reaction of ammonia, water vapor, nitro
`Ygen tetroxide and oxygen,V that improvement the residual gas, cooling the gas prior to addition of
ammonia thereto to about 40° C., and maintain
v which comprises cooling a‘gas containing nitro
mixture having substantially the same composi
tion and temperature as the ñrstmentioned gas
mixture, and employing the resulting gas mixture
for the production of ammonium nitrate in the
gen tetroxide-by directly contacting said gas with
an aqueous nitric acid solution and mixing e‘n
tween about 40° C. and 125° C.
monia with the ' thus` cooled gas.
i 13. In the process of `producing ammonium ni
trate by'reaction of ammonia, water vapor, nitro
igen tetroxìdel and oxygen, that improvement
`which comprises cooling a gas containing nitro
gen tetroxide by directly contacting said gas with
. an aqueous medium and mixing ammoniawith
the." thus cooled gas.`
i
,
’
i
14. In the process of’producing ammoniumV ni
trate by reaction ofY ammonia, water vapor, nitro
gen tetroxide > and oxygen, that improvement '
Vwhich comprises simultaneously cooling and ad
justing the water vaporV content of a gas con
f taining nitrogen tetroxide and oxygen by directly
contactingsaid gas with an aqueous nitric acid
‘ A solution having a predetermined composition and
temperature and mixing Yammonia with the thus
cooled gas.
Ä
ing the temperature of the reaction mixture
formed by each of said additions of ammonia be
'
` 15. The process oî‘producing ammonium ni
trate which comprises simultaneously cooling and
adjusting the water vapor content of a‘gas con
taining oxygen andl not more than about'6.5%
nitrogen'tetroxide by directly contacting said Vgas
with about 50% aqueous nitricacid solution at
a temperature of about 40° C.,'and introducing
_ ammonia into the'thus cooled gas.
16. The process of producing ammonium ni
trate which comprises simultaneously cooling and
.
19.111 the process of producing ammonium ni
trate by `reaction in the gaseous phase of am
monia, water, nitrogen tetroxide and oxygen, that
improvement which comprises reacting on said
nitrogen tetroxide, oxygen and water vapor with
ammonia in a plurality of stages and limiting the
quantity `of ammonia available for reaction with
the nitrogen tetroxide ineach stage to not more
than about 0.3 times the amount required to neu
tralize all of said nitrogen tetroxide in each stage
to form ammonium nitrate.
' v
20. In the process of producing ammonium ni
trate by reaction in the gaseous phase of am
monia, water, nitrogen tetroxide and oxygen, that
improvement which comprises reacting on said
nitrogen tetroxide, oxygen and water vapor with
ammonia in a plurality of stages, and limiting
the quantity of ammonia available for reaction
with the nitrogen tetroxide in each stage to less
than about 0.25 times the amount required to neu
tralize all of said nitrogen tetroxide in each stage
to form ammonium nitrate.
2l. The process for the production of ammo
nium nitrate which comprises circulating a gas
containing nitrogen tetroxide, oxygen and Water
vapor in a circulatory system and during the cir
io
culation of said gas admixing therewith ammonia
whereby ammonium nitrate is produced, limit
ing the quantity of said ammonia to an amount
.adjusting the water vapor content oi’fa gas con
taining nitrogen tetroxide and oxygen by directly less than about 0.3 times that required to neu
contacting said gas with an aqueous nitricacid , tralize all the nitrogen tetroxide in the reaction l
solution having a predetermined composition ,and
mixture, separating ammonium nitrate thus pro- _
temperature, introducing ammonia into the thus
`duced from the residual gas, removing from the
,cooled gas in amount insuí-Iicientto completelyA circulatory system heat liberated by the‘reaction,
Vneutralize all of the nitrogen tetroxide therein
~ to Aform ammonium nitrate,- separating the resid
ual gas and ammonium nitrate thus produced,
introducing into the residual gas nitrogen tetrox
ide and oxygen, cooling and adjusting the water
vapor content of this gasby directly contacting
and adjusting the nitrogen tetroxide, oxygen and
Water vapor content of the recirculating gas prior
to admixing ammonia therewith.
22. The process for the production of ammo
nium nitrate which comprises circulating a gas
containing nitrogen tetroxide, oxygen and water
vapor in a circulatory system and during 'the cir
culation of said gas admixing therewith ammonia
mixture having substantially the same compo
sition and temperature asV the aforesaid cooled- whereby ammonium nitrate is produced, limiting
the quantity of said ammonia to an amount less
gas, and employing the resulting cooled gas mix
ture for the production of ammonium nitrate in` than about 0.3 times .that required to neutralize
all the nitrogen tetroxide in the reaction mix
the manner hereinbefore described.A
’
ture, separating ammonium nitrate thus pro
17. The process of producing ammonium ni
trate whichcomprises introducing successive ad duced from the residual gas, bleeding from the
ditions of ammonia into a gas containing nitrogen circulatory system a portion of the gas therein,
= itA with aqueous nitric acid to produce a gas
_
-
tetroxide, oxygenV and water vapor, limiting the
quantity of» each laddition of »ammonia to an
amount less than aboutY 0.3 times that required
to completely neutralizeall of the nitrogen te
troxide in the gas into which said addition is
e
introduced, separating ammonium nitrate formed
admittingto said system additional quantities
ofY gas containing nitrogen tetroxide and oxygen,
Ycooling the circulating gas and adjusting its con
tent of waterl vapor-prior to admixing the am
monia therewith and so correlating the aforesaid
steps of the process as to maintain substantially
~ l«mists-ua >the» conditions 'un ,der i which, each> Èsœp' nium "nitrate fora periodici timein ¿relativelyV
' of the process> operates. ,ÍY
"quiescent condition. Y "
:_23. The A processy for’tlie' .production .of ammo I Í >`28'. They process for the _production „of“ ammo- j
‘ nium nitrate wiiicli comprises circulating >a, gas nium `~nitratewliicl’i 'comprises recir'c'ul'ating> a gas~ `
rcontaining nitrogen > tetroxide, oxygen ,and L'Water
vapor in a circulatorysystemV
nitrogen'tetroxide,oxygenandlwater
and „during the-cir- I $1
^ Vapor inajcirculatory systemandduringv the cir Y containing
jculation >of said gas admixingitl’icrewith amino- . Youlationl of saidl gas admixingtherewith succes
' niawhereby'anunonium„nitrate is produced, lirn- :
' iting the quantityof said ammonia` tojan amount
’ less than aboutgoßtinies.thatjrequired to neu
sive‘additìons of ammoniafto- produce ’ammonium _'
` nitrate, separating the Yresidual gaszand A'ainmo- '
nium nitrate, adding to :the residual gas nitro 'l0
gen tetroxide andoxygen, adjusting the tempera
vture and watenvapor content of the circulating
prior'to the addition tlieretoîof ammonia,
circulatory system aportionof the gasl therein,> ¿gas
>.continuously Ywithdrawing'fr0-in the aforesaid cir
- adnn'tting to-said systemv auditienal> quantities ifoî culatory» system a' portion of the gas' circulating
,s v.gas containing 'nitrogen tetroxide and oxygen,
therein,v passing the withdrawngasinto a'sec-¿
>cooling the’ circulating Ygas, and adjusting itscon-v -, ond'circulatory
system wherein it is recirculated
tent; ci ,water Vapor prior to adinixing thefain
and duringÀ its circulation in said secondV system
,tralizefall'tne‘ nitrogenltetroxide in the reaction
'mixture Yseparating. ammoniumrv nitrate thus’pi‘o- l
(duced from thefresidual gas,l bleeding'froinxthe
f monia'tlierewitli ,e by direc lyl contacting said Ygas
withv an aqueous solution ‘of Ynitric aci d'prior tog'. I >mixing said gas with successive additions >of am
toproduce additional ammonium-nitrate, ‘
admixing tlie> ammonia, therewith,v and’ main monia
separating the residual gas and Yainx‘noniurn ni
taining the temperaturegof the reaction mixture v tratetlius produced, adding to `the residual gas
Y Y of ammonia andsaid circulating. gas below about
f 24. The vprocess, for the production ofi-'ammo
nium nitrate` which comprises ,circulating a gas
the gaswithdrawn fromçth'e iirst mentioned cir- i
` culatoryfv system„'and adjusting thev temperature
and ,water Vapor;y content of tne'circulating gas, -
containing nitrogen tetroxide, oxygen and water ‘ landin both of the aforesaid, circulating systems n
limiting the amount of each’oi’ saidfadditions ofY
_vapor in a circulatory system and during the cir
thecirculating gasto not
oula'tion'of said gas adrnixing' therewith ammonia ammoniaadmiiied
whereby‘arnmonium :nitratev is produced limiting v , more thanuilß timesr thatrequiredV to neutralize
the quantity ,of said ammonia to anamountbe-z . all the-nitrogen tetroxide `present inthe reaction »
tween’about 0.1 'andfûzätirncs'that required to
i neutralize lfall the nitmgenV tetroxide in the. reac
tion t mixture,Vv separating ammonium nitrate Vthus
produced from tlie residual vgas,.bleeding fronitlie
mixture and maintaining the reaction mixture at ~
¿temperature below about 1725970.`
v
y
_29. yThe-process for tlie production'fo'i ~ ammo
niurnr nitrate which comprises recirculating a gas ‘
nitrogen tetroxidaoxygen and Water
ucirculator system al portion` loi ‘the gases therein,v ., 'containing
vapor in acirculatorysysternand"during-the cir
oo
¿admitting to4 said lsystem additional >quantities
oi gas containing. nitrogen tetroxideand oxygen,-- culation of said gas admixing Vtherewith succes- '
cooling'tlie circulating v'gask and adjusting its "c'on- ` lsive additions of y,ammonia to -produce ammonium
tent
oiiwater vapor by directly’ contactinglit with vnitrate,ttrnaintaini_ng the reaction mixture at a
40
separatingrthe
an aqueous solution' of, nitric acid containing about ` temperature,belowabout 125°
.e >5o %fnitric acid at a'temperature of »about do" 16.1,@ r>residual,gas and ammonium nitratefadding to
ther residual >>`gas nitrogen tetroxide ' and ì oxygen,
and maintainingthe Ytemperature- of the reac
l tionrnixture of ammonia and-said coolcdgas be
low about «125° C;
y45
‘
adjusting` theìtemperaturefand water Vapor con
v tent of the >Acirculating gas rI'Jriorvato’t’ne addition
f `25. The processor,l producing ammonium ni- ">V'thereto;'orammo-nia,
‘ n
40v
by directlycontacting said
4:5
'trate which comprises;y admixing successive ,addi-, ¿g-a's withl an aqueous solution o_f nitric acid at a
tions of aininoniafwith a gas containingnitro- „ temperature of abonnees; o., continuously witn
gen tetroxide,v oxygen,l andrv water Vaponelimiting f "drawingffrornthe aforesaid circulatory system a
the quantity 'ofv each addition kof .ammonia rto-an '
iportionjof the, gas circulating therein, passing the
amountY insufficient to'completely neutralize the f withdrawn gas íntoa second Vcirculatory system
nitrogentetroxide in ,the gas admiXed therewith; wherein it is circulated and during its’circula
50
said second system mixing said-gas with`
'1 and maintaining the temperature of the reaction « tion
¿successive additions of ammonia toproducev ad
mixturebelow_alooutflZëio C.-A
v
v
,f
,
Yditional ammonium nitrate,`„niaintaining. the re- Y i
26. .The 'process' of `producing fammoniinnl m'
5-5 - Vl trate ¿which comprises gadm'ixing i successive Vaddi A`actionmixture,,at a temperaturel below >about '
' tions oiammonia with- a gas containing nitrogen ` i25°»C.,1-separating the residual gas andammo
»
tetroside,` oxygen/and. water vapor, limitingâtlie> `
, quantity of' eachladdition of ammoniaito anvr
nium nitrate thus produced, adding vto the resid
ual gas, the jgas Withdrawn fromthe first’ men
f 66’ amount Vless than about 0,25 times that required ¿ Y tioned circulatory systemga'nd adjusting thek tem
to completely neutralize-fthe nitrogen tetroxide in peratureìand rwater vapor content :of tlie, circu
_ the> gas admixed therewithgfand >maintaining the ' lating gas byA directly contacting'said >gas withv an
temperatureoi the reaction mixture below about* '_ aqueous solution- oinitric acidat a temperature
k.lofaloout40j’
C.v
"
'
'
Y
'
‘
'
î"
60
’
Si).y The' process ofp'rodu f ¿U ammonium' nitrate
27”"1‘1'19 process O‘f producing ammonium. nir à .which rcomprises( admixing ammonia Iin 'a plu
65"' trate whicliï comprises-admiring successive addi
v tionsof'ammonia’with sigas-„containing nitrogen rality of stages with-’a gas coranrising> nitrogen
65
tetro’aide, water Vapor 'and a'quantity4 of oxygen
Y, "tetroxide, oxygen and watervapor, limitingthe 'Y' not'greater‘tlianra’oout
10%,of the tota-l'volume v
` quantity oi each addition vofV Vammonia-to; an
of _:sai-dm».gas',V liiniting'tlie quantity of ammonia
amount insuiiicient to ceinpletelyneutralize the' lavailablefor
reactionwiîth/tlie nitrogen tetr-oX
Y 4¿nitrogen
y_maintaining
tetroXide
the` »temperature
inthe gas admiredr
of? the'reaction
therewith, -` ide in?eacli stage VVto V:not more than about 0.3 timesk
amount'reduired lto neutralize all of said ni
rmixturejbelc'lw about 125°Q'C’. and intermediate’ kthev
trogenitetroxide'tcfi‘orm
ammonium nitrate, and
f theintroductionv of twoïfoi said additions’of'am
yrrionia maintaining-the gasV containing ammo V*maintaining the reaction-mixturein each 'of saidl
stages'at a temperaturefbelowabout i25f’ïC;- U A
75
'
¿.9
2,011,704
to . a , temperature. of about `~ 409 i C. ' and adjusting
. 5F31. The'fpro‘cess ‘fori the f'production 'of ammo-_~
niun'fi> nitrate` which - comprises mixingV ammonia
therwater vapor content by directcontact of said'
with Va 'gas'containing nitrogen tetroxide,lloxygen{
and Water vapor, said water vapor’being Vinl amount
in excess of that required toreactwith» allthe'
nitrogen tetroxide `butlinsuiiicient `to Íorm'ïa liquid
condensate in the aforesaidI gas! at 'temperatures
above about 40° C; andl maintainingîtiiefreacting
mixture of ammonia and said gas at" temperatures
gas vWith aqueous nitric acid.
u 32.` The `process for the -productionof 'ammo
nium ‘ nitrateWhich - comprises i mixing ammonia;
nitrogen tetroxide; oxygen l and ' Äwater . vapor . in
`
.
'
‘
more than .about 6.5% nitrogen tetroxide, _' and
oxygen into »direct contact‘with an aqueous solu
tionsof nitric acid containing about 50% I-INOs at
about 40° C,-,Jintroducing ammonia intorthe thus
treatedgas in amount' insufficient tov neutralize
1 part 'of nitrogen tetroxide, and from 0.5 to 2.5
parts ofiwater vapor. »
l'
ï 39. iThe process of producing ammonium nitrate
which `-comprises` passing a ,gas containing not
'the proportions of less than 0.3 parts of ammonia,
-
A
thenitro'gen tetroxide toform ammonium nitrate.
within'the fange' of about.4o°.c.m1125120. f
Y i5:
'
1 v38; The process of producing ammoniumnitrate
which» comprises introducing 'ammonia' into ça gas
>containing oxygen, Water vapor andnot more
than about"l6%' nitrogen tetroxide and limiting
the quantityof ammonia‘to` an amount less than`
about 0.25 .times that required to neutralize’all
f
~*»L33.`~The process for the production .of ammo
allV the nitrogen tetroxide contained thereinfto
ammonium nitrate, and maintaining the re
nitrogen tetroxide; oxygen: and v‘livater Vapor'. in 'Y form
acting mixture of'igases Vat atemperature below 20A i
the
.proportions
.'of.
not
more
than'aboutiûßparts
20V
ì
l.
_
.
v
_'
of ¿ammoniagabout `l part ofïnitrogen tetroxide al:noui',‘125.";C.n , . .j ‘1
V14,0."I‘he process of producing ammonium
and between >about 0.5„andï 2.5 parts of Water nitrate
which comprises .passinga gas containing
, vapor and maintaining the» temperature oflthe
not
morefthan'about
6% nitrogen'tetroxideand
reacting Vgases between about. 40° C.` and 125° C. oxygen into direct .contact with an 'aqueous solu
" 34.. The process of producing ammonium nitrate
of nitric acidcontainingabout 50% `I-INOa at'.
whichy comprises introducing successive additions tion
about 40° C., introducingammoniainto the thus
of ammoniainto a gas containing.nitrogenxtetrox
gas in amountflessA than about 0.25»times
ide,.oxygen and Water vapor, said gasxcontaining. i treated
about 0.5toy 2.5 parts of `Water vapor. to >.every .1» that. required/to ` neutralize. allí `the l nitrogen 30.:
contained therein, maintaining` the. re
co. part of nitrogen tetroxide, limiting the quantity ' tetroxide
actingfrnixturerof
gases at atemperature below;
vof` each addition. of'` ammonia toan amount less
about
"125".`
C.,.separating
the ammonium nitrate
than about 0.25v times' thatlrequired tocompletely.
neutralize .all of thenitrogen tetroxidev in thegas thus Aformedïfrorn theresidual gases; and react
ing the .residual gasiwith .an `additional quantity
into which said addition is intro-duced, separat
ammoniaunder substantiallythe‘same condi-`
ing ammoniumnitrate `formedfrom the residual of
tions as; hereinbeforev describedgfor the ï ñrst
‘ nium nitrate which! comprises mixing. ammonia,
.
gas,v cooling the‘gas prior tolthe addition of am
moniathereto by directly contacting it with an
aqueous nitric; acid solution at a vtemperaturegof
. -mentionedl gas 'containing nitrogen , tetroxide and
about 40°, C., and maintaining thatemperature
'
4o».
ofy thewreaction mixture formed by `each vof said
Y additions of ammonia-below about. 125? C.
*85. The processjoi producing ammonium nitrate
which> comprises introducing a concentrated’am
_monia gas into amixture of, nitrogenoxides,
45'»Y oxygen’and ‘water vaporiin which .80% or more
of the nitrogen oxides `are present as nitrogen
tetroxide and limiting the quantity of ammonia
to not more than 0.3 times the amount required
to neutralize all of the nitrogen tetroxide to form
ammonium nitrate.
Y
Y
`
’
Y
36. The process of 'producing ammonium nitrate
oxygen.,
,
.
,
„
.
.
.
,
i
‘ '41.1'Intthe processyof producing ammonium
nitrate-.by reaction in the `gaseousphase of am-`
monia, Water, nitrogen tetroxide and oxygen, vthat
improvement `Which comprises introducing arn
monia into a'stream of gas containingnitrogen
tetroxide, -oxygen and. Water vapor` `While lme
chanicallyimparting a turbulence to. said stream 45.
of gas.
`
42. In the process of producingv ammonium
nitrate by reaction in the gaseous phase of am
monia, Water, nitrogen tetroxide and oxygen,
that improvement .which comprises introducing a 50
restricted flowing stream of concentrated am
Which comprises introducing a concentrated am
monia gas into a flowing stream of gas contain
the course of the reaction at a temperature be
, that improvement which comprises introducing a
monia gas into aA mixture containing nitrogen ing nitrogen tetroxide, oxygen and Water vaporV
tetroxide, oxygen and Water vapor, limiting the While mechanically imparting a turbulence to 55
said last mentioned stream of gas.
quantity of ammonia added to an amount insuffi
’43.-In the process of producing ammonium
cient to neutralize all thenitrogen tetroxide con
nitrate by. reaction in the gaseous phase of am
f tained in said'gas mixture to form ammonium ni
trate, and maintaining said mixture throughout monia, Water, nitrogen tetroxide and oxygen,
60 low about 125° C.
'
37. The process for the production of ammo
nium nitrate Which comprises recirculating a gas
containing nitrogen oxides, oxygen and Water va
por in a circulatory system, introducing a con
65 centrated ammonia gas into the circulating gases
in amount less than about 0.25 times that re
quired to neutralize all of the nitrogen tetroxide
in the gas admixed therewith, maintaining the
temperature of the reaction mixture below about
70 125° C., separating from the residual gas the am
monium nitrate thus formed, and prior to recir
V culation of the residual gas for introduction there
into of ammonia, replacing the nitrogen oxides
and oxygen removed from the gas in the forma
.15.
tioniofV ammonium nitrate, and cooling the gas
stream of concentrated ammonia gas flowing at 60
high velocity into a `stream of gas containing
nitrogen tetroxide, oxygen and water Vapor While
mechanically imparting a turbulence to said last
mentioned stream of gas.
'
44. The process of producing ammonium 65
nitrate which comprises preparing a mixture of
nitrogen tetroxide, oxygen and water vapor hav
ing ‘a temperature of vabout 40° C., introducing
ammonia into a turbulent stream of said gas,
limiting the quantity of ammonia thus intro 70
duced to an amount not greater than about 0.3
times the amount required to neutralize all of the
nitrogen tetroxide, and maintaining the tempera
ture of the reacting mixture of gases below about
75
125° C.
'
aorn'zofri
t
y
_
v
_
into aturbulent stream _of the thus
"nitrate whichf=comprises icirculatingja gasirconi-rv fzfnonia'igëlis>
taining nitrogen tetrOXidêi Oxygen-,fand water treatedmixed gas in'amount between about 0.1
y
y ` vapor'ifin'a'?circulatory systemand 'in‘saidïsystem'
introducingM arconcentrated: ammoniaifgas ¿into AaY
_and O.»25„timesfthefamount required to neutralize
allfofpthenitrogen tetroxide inthe gas,r maintain
ing the thus treated gas fora period of time in a ‘i5
' turbulent stream of'said gas‘inlamount less »than Y „relativelyquiéscentcondition, lintroducing a `iîur- ’
about0;25'timesthe >amountfrequired ,to neutralize
‘ all of ’the nitrogen tetroxide inîthe gas, separating
Y ammonium nitrate thusgforin'ed from therfesidual.
ther yquantity of, a ,concentrated ammonia gas
into `al;turbul'er'rt: streamofV the/thus treated gas _ f
103 gases,"introducing nitrogen tetroxide and oxygen: . inA amount ¿between about A0.1 and 0.25 times-the
into the J residualzgas f iniamoun’t 'fsuch that :the amount Tequiredto neutralize all of the nitrogen 10S
tetroxide t in the > gas,- separating A,the , ammonium
` ' resulting, » gas , mixture` containsg notzgmoregthan
f aboutjf`6% :nitrogenftetroxide vand.' directly con-v ' nitrate 'thus vformed Vfrom the` residual rgas', With-`
.. drawing; from the ; second Vcirculatory ’ system . a
- tacting saidgas'mixturewitlisan' aqueous solutionr ,portion-fof V'saidfresidualz gas, and mixingy the ref
,l'öï ófv nitric> acidv vcontaining"about C50%;¿I-INOi ~at a _ Y
S'ídual -gas containing nitrogen "tetroxide, oxygen
_ s temperatureïót about 4D?. C'.> prior tofthe introduce '
- tion thereto’ of 'ammoniaïgasfas shereinlìnefore"y
described. » ~
Y and'water Vvapor remainin'gzin said system Ywith «
the'gas Withdrawn from the ñrst> mentioned cir- ’ '
‘
culatory ¿system as >hereinbefore described.
processY 'of Í producing` fs'ammoniumf `v`"147„An
apr'naratus:fon/thev production ofY am
20': nitrate Whichqcompris'es >circulating aîgas con-.
taining nitrogen ',tetroxide, f oxygen and ',Wate'r.
vapor‘ïin acirculatorysystem anduinisaidî system
introducing-arconcentrated ammonia gas into> a
" ` turbulent ïstream , ofi'> said" ‘gas‘firrfamount “between
moniuìngfnitra'te; by"y vreactìonzof ammonia, lWater
y Vapor, ,el nitrogen ítetroxidel and Y oxygen, compris-` i
ing/a ,çlosedcoirculatory system», said‘syst'em
comprising _.in Y'combinationv agas cooler, a reac-`
tionyessel :and a"separator.„for removing :a solid
>from'aV gas 'in whichit issus'pended all connected
separatingzammonium íirn'tratefY thus vr‘formed from ,s .byoonduits for circulation'?of‘gas therethrough,
1 l theïresidual gases; ' removingrffrom'; the `system-,- a
meansfor .introducing gaseousreactants into said`
portionA of >,the ~ residualgas; introducingV *nitrogenA > ks5VIstern',`f¿said,means comprisingmeansfor intro
ducing Y, into.. said.> reaction' vessel at' least vone* of
303y tetroxid'e and :oxygen into ïthe'jresiduaJ-¿gas fre-ï ‘the
gaseous..lreactantsjseparate from the others,
't mainingfíri said" system,'1in amount/suoli ¿that the' ' means'ïorsrecirculating:
gasintrodu‘ced'into the »
f" >resulting"gas:mixture contains'about-È5%"î`to 6%,
nitrogen tetroxide;l Ydirectly f'contac'ting said .gas _ system .fin Vseries-.through saidV coolenreaction ves
sel ¿and separating means; and aïsecond closed
mixture lwith" »an‘ï'a'queous solutionèerof ßnitric; Aacid ' circulatorysystem'
comprising'inícombination a
l' :containingv about v510% „HNOsqatjV aêtemperature of
>gas
'coolenia
vreaction
and a separator Yfor
i kabout 40°
prior `to- thefiìntròduction thereto rremoving(alsolid fromVessel
a >gas irrwhichY it is sus
ducingtheresidual
ófïamxnoniajgas’as herein'before
gas removed describedgíntro,-V
from the faforef; ' pendedè meansfor'withdrawing a portìon'of the
i -Said. circulatory system yinto >asecond rcirculatory gasfcirculatingS in the Ílrst v'mer’ltíone'd circulatory '
1 ¿01 (system,` mixing Isaid„gasìwitl’lraf ga'svcontainingf ` ' system» and: introducing> it pintoV vthe" .second cir
_
culatory .Is5.fstem“,~- means forvintroducing gas-> into 40
the lastifmentione'd reactifvnrí,~r Vessel, and means
culated»~therein», t directly contacting thesamixed i rforrecirculatirig'gas introducedl into said second "
Witlí'anaqueousrsolution of` nitric acid »con-vr systernf-¿inY seriesy throughA the' cooler, reaction
tainingabou'ta50‘Zg` .I-INOsÁ at a-temperatureiof ' t `vessel
and `separator offsaidsyste .
'
Y'
~ gases~
l 'about' ‘40° .i Cgi!! introducing ¿alzconcentrat'ed i .am
HERMANALBERT BEEKHU'IsgJR.> ¿5
«
v