PERMFILE113041

• Permit No: M1999002
• IBM Index Class Name: Permit File
• Doc Date: 6/18/1999
• Doc Name: Objectors Exhibits
• Media Type: D
• Archive: No

x,588,713
solutiotu by tse of solubility suppression w:[a addition of
s~:.
I[ is anothe object of this invention [o provide a prottss
for making sodium bicarbonate from Naheoiite-rich solu-
tions which conserves water by utilizing minimzl quantities
Of water in the process.
Another objet: of this invcndan is [o provide a vroeess for
:.icng sodium bicazbonau from Nahcofite-rich solutions
watch conxrves energy 6y r-,cycling hot condensa[e mo-
du¢d in [he process for use in the initial sup of divolving t
Nahcoli[c from the formation.
Another object of this inveadon is [o provide a process for
making sodium bicarbonate from Naheoli[e-rich solutions
which is not in0ucnccd by the purity of the pmgnant liquor.
Another object of tJtis invrntion is to provide z process (or t
making sodium bicazbona[e from Nahcolitc-rich solutions
which can be used to recover Nahcolite from salt contami-
nz:cd formations or surfars processing facilities where the
oregnan[ licuor contains salt in excess of 6%.
A furhe object of [his invention is to provide a process
for raking sodium birarbonate tram Yahr-oG[c-rich salu•
[:ohs which produces salt (NaCI) as a saleable by-product
a.^.d eliminates the need for large s:uface containment arras
far collection of purge liquors.
A still funkier object of this invention is m movidc a
process for matting pure sodium bicarbonate irom Nah-
coli[c-rich solutions which is highly erhrirn[ and cos[ effec-
tive
O[he objects of the invtastian will become apparent from ~
time to time throughout tae spcdfiration roc' claims as
hcrciaafte rc!ated.
T.nc above no[ed objects and other pbjems of [he invention
arc accomplished by a process for waking sodium birar-
bonau from Nahcoli[e•rich soludons which utiirls solubi]- ~
icy suppression wi[h addition o(salt Hot wale: pumped into
a \'ahcoiite-rich formation, wrich may contain salt (NaCI)
and o[hcr impurites ir. excess of 6% by weight dissolves the
\ai:colite (NaHCOs) and salt The dissolved Nahwlite is
brought :o the surface as a pregnant brine liquor containing ~
Nahcolim, salt and other imouriucs, winch is then do-gasxd
under pressure. Tne pregnant liquor is then otlscd with a salt
slury and iu sempeztur~ teducrA to saturate i[ wi[h salt and
force prcdpitauon of Naheolite out of the prcgnznt liquor.
Cazbon dioxide (COa) is injated wisiie tniziag the prcgvaat ss
licuor with the salt to facilitate prcdpitation and wnversioa
a( any sodium carbonam (Na._COa) present into sodium
biczrbona[c (NaHCO,). The sodum bicarbonate (NaHCOa)
is dewazered and filtered ro form a sodium bicarbonate
(NaHCOs) film: take, which ~ washrd wins fresh cold water ~
to remove salt (NaCI), sodium czrbonate fNasCDs), cad
othr, impurities as a salt-rich brine filtrate. and the filer rake
is dried to produce a high grade of aansm! sodium birar-
bonate (Na1-1COs). The filtate tnay be processed ro produce
ho[ waze condensa[e which ran than be used m dissolve the g
Nahcoli[e, and the salt slury produrd can be used to
samrau the pregnant liouor and fore Nahcolite orccipita-
don, cad a trorion may be dded cad used as a saleable
by-product.
BRIEF DESCRIPTION OF THE DRAWINGS ro
F1G. 1 is a scbeasane flow diagram illustrating the process
for nsaldng sodium bicazbonate fmm Nahcolite-rich solu-
tions in accordance with [he present invention.
FIG. 2 is a gzph showing solubility of various mixes of ss
sodiur.. bicarbonate (NaHCOs) and salt (NaCI) at various
tr...pc:amres in deg,:ccs F
DESCRIPTION OF THE PREFERRED
EbIDODIMEhT
Refemng to the d.-awings by numerals of ;etc:ence, there
s is shown schctuatically is FIG. 1, a p:efa:ed process foe
making sodium bicarbonate (NaHCOs) from Naheoii[e-rich
soludons by use of soiubiiity suppression w-i[h addition of
salt (NaCI) in aaordanre with d[c prescat invention. Thc
prorsss is charzcteized by the (oilowing steps:
p (a) Hot wale (H,O) in the mmoeraturc range of from
abou[ 160° F. to about ?30° F. is pumped at a messurc
of zbou[ I50 psig into an underground Nahcolite
(NaHCOa)-rich fotmatior_ which may contain salt
(NaCI) and o;her:mpurines in excess of 69° by weight,
~ [o dissoivc the Nahcolitc INaF[COs) and salt;
(b) The dissolved Nahcolite (~aHCOs) is brought to [he
surface of the for..a[ion in the forth ota saturated brine
pregnant licuor solution containing Nahcolite and may
also contain szlt (NaCp and other im_ouritin in excess
m of 6% by wr'ght:
(c) The prcg--an[ liquor solurion is dc•eassed under a
pressure in the range of from about 100 psig [o about
30 psig in z pressure contvllcd system:
u (d) Tne de-gasud pregnant liouo: solution is nixed with
a salt (NaCI) slurry which may rypicaily contain about
90%or mate NaCI, by wrieh[ of rota! salts presea[, and
the tempt: an::e of the dcgsssed or-_gnea[ liquor solu•
non is reducd m the mngc of from abou[ 200° F to
about f60° F, which is n.-meteor [o saturate rite de-
n gassed prcgoan[ liquor solution with salt (NaCI) and m
force prcopitatioa of Nahrolite (NaHCOs) ou[ of the
degassed pn:gnan[ liquor solu[ion:
(c) While roving dse de-gassed p:egran[ Gauoc soludon
s with the salt (NaCI), carbon dioxide (COs) is injecud
into [hc mixcuc to farilitate orecinitation and ~on~e.^-
Sion of any sodium carbonate (NasCOr) present into
sodium biro-boantc (Nxi-ICOa):
([) The sodiuv biarbonate (NxHCOs) is dewa[ered and
filtered. usin¢ a rnmbipadon of hydrorycloaes and ~a
vacuum fi!tr, or centrifuge, ro form a scdium bieaz-
bonau (NaHCOs) 51ter rake, and tae 51[e cake is
washed with fresh wld wzte :o remove salt ("faCl).
sodium rarbaaate (NarCOs), and other impurities as a
salt-rich bdac Nvatc; and [hereafter
(g) The washed sodium bicarboaatc (NaHCOs) file rake
is dried to modus a high grade of rsattaal sodium
bicarboaatc (NaHCOs).
To farilitau th-, process of de-gassing Ne pregnant liquor
solution and forcing preci~tauon of Nahcolire (NaHCOs).
the prcgaant liquor solution undo pressure i.-t the oressurt~
wa[roiled systm at step (c) may also be cooled at this step
to a [evpcaturc m [tie rarsge of frov abom l60° F. to abou[
70° F. prior m rrtixing it witit is salt (NaCI) slurry, and rhos
further reduced ro a temptxasre in the range of from about
70° F to about 50° F. as it is mixed with the salt (NaCI)
slurry u step (d).
The emciency a.-sd cost efrectivcness of the present vro-
cess is improved by processing rte salt-rich brine iiltrau
containing sal[ (\aG), sodium cazbonatc (Nz,COo), and
oche impurities, winch was removed during the washing
step (f), using vxunical rcrompression crystaliza[ion,
multipic rBcct cystalizanop. or waste heat from a co-
geaeradon plant to produce a hot coadrnsatc of water (H_O)
and a salt (NaCI) slurry, The ho[ condensa[e of water (HrO)
can rhea be pumped taro the underground Nahcoliu
(NaHCQs}rich forvanon and used to dissolve d:e Nahcolitt