close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2105126

код для вставки
Jan. 11,1938.
J. 5, PELLETT
2,105,126
CLASSIFICATION
Filed April 1, 1936
@914
a
I
L
3 Sheets-Sheet l
I
,
H
|
45
39
46
m
47
J8
-::;—:::
v
‘
'
ET:
410
.
M
19/
~44
_
_
—
_
'“
_
_
_
_
@w
fazi
f‘x
"f?
54/
rzj
-
’
455
7.“
"94
INVENTOR
,
‘
'
1/226115'092
J'JDeZ/df
BY
77M/ 2%, 7%,”; WM
ATTORNEYS
Jan. 11, 1938.‘
J. 5. PELLETT
‘
2,105,126
CLASSIFICATION
Filed April 1, 1956
>
f6 '1 -
"
Z/
“1
" '
/
3 Sheets-Sheet 2
If
I
\NVENTOR
Jim/{1502? JPéZ/e?
BY
7W; QM, Wm’ WM
ATTORNEYS
Patented Jan. 11, 1938
2,105,126
/
UNITED STATES
‘PATENT OFFICE
2,105,126‘
.
\
-
CLASSIFICATION
Jackson S. Peliett, Franklin, N. J., assignor to
The New Jersey Zinc Company, New York,
N. Y., a corporation of New Jersey
Application April 1, 1936, Serial No. 72,014
20 Claims. (Cl. 209-158)
This invention relates to the classi?cation of . propriate head of water (indicated by x) is main
comminuted mineral: particles by hindered set
tained in the pipe H by supplying water thereto
‘ tling andhas for is object the provision of cer
at a. constant rate through a valved outlet l8 of
tain improvements in the method of and appara
a water tank [9 having an over?ow 20 to maintain
tus for hindered settling classi?cation. '
a constant level of water in the tank. The top of
In vhindered settling classi?cation, a pulp of the hydraulic compartment I 6 is provided with
comminuted mineral particles in suspension in '
a plurality of nozzles 2|
water is passed over a chamber or series of cham
of water into the bottom
bers provided with a constant stream or streams
10 of rising water against which the mineral par- , ber I5. The nozzles 2|
which may be attached
ticles settle in a crowded but mobile condition, the
chambers being provided with spigots or the like
for discharging the classi?ed product. The in
vention contemplates an improved method of
and apparatus for controlling the discharge of the
‘ classi?ed pulp (i. e., pulp which has been sub
~jected to classi?cation in the chamber) in- re
sponse to changes in_the density of the pulp
undergoing hindered settling. Thus, in accord
ance with one aspect of the invention, the dis
charge of classi?ed pulp from the classifying
chamber is automatically increased "or decreased
as the density of the pulp undergoing-hindered‘
settling increases or decreases. In the preferred
‘form of the invention, the contemplated control
of the classi?ed pulp is effected by discharging
the classi?ed pulp into a control zoneor reservoir .
for introducing streams
of the classifying cham
are covered by caps 22
to the roof or cover of 10
the compartment by brackets 23 (Fig. 2). The
compartment I6 has a drain pipe 24 in its bottom.
In practice, the classi?er generally comprises
a series of adjacent classifying chambers over
which the pulp to be classi?ed progressively 15
passes. In such a classi?er, the diameters of the
pipes l‘l progressively decrease from the feed end
of the classi?er, at which coarse material is-treat
ed, to the discharge end, at which ?ne material
is treated; that is to say, the water supply pipe
II for the ?rst chamber of the classi?er (‘feed 20
end) will be larger than the water supply pipe
II for the second chamber, and the water supply
pipe for the second chamber will’ be larger than V
that .for the third chamber, and so on. The
widened or ?ared portions I 5’ of the series of 25
chambers guide the discharge-of water and ?nes
in. which a hydrostatic pressure is maintained,
and then varying, preferably automatically, the - to an appropriate launder at the discharge end of
30 hydrostatic pressure in the control zone in re
sponse to changes in the density of the pulp un
dergoing hindered settling. These and other
novel features of the invention will ‘be better
understood from the following description taken
in conjunctionwith the accompanying drawings,
35
in which.
'
s
-
Fig. 1- is a diagrammatic ‘sectional elevation
of a hindered ‘settling classi?er embodying the in
vention,
'
40"
-
,
Figs. 2, 3, 4 and 5 are detail sectional elevations
illustrating various devices for ‘supplying rising
the classi?er.
‘
.
.
I
The classifying chamber I5 is provided (at a
substantial distance above the nozzles 2|) with 30
a spigot ~2i‘: for the discharge. of classi?ed pulp '
into a control reservoir 26. The ?ow of pulp
through the spigot 25- is determined by the differ
ence between the hydrostatic pressure prevailing
in the reservoir and the hydrostatic pressure due v 35
to the pulp'in the classifying chamber IS. The
hydrostatic pressure in'the reservoir 26 results
from the head of water (indicated by ,Z) in a pipe
21 for supplying water to’ the; reservoir. Per
forated baffles 28 and 29 are provided near the top
and bottom, respectively, of_ the reservoir for dis
tributing the ?ow of water through the reservoir
to the discharge outlet '30, and thereby prevent
Figs. 6, 7 and 8 are diagrammatic sectional ele
ing the development of a vortex that might with
vations of hindered settling classi?ers embodying draw pulp through the spigot 25 by suction. The
modi?ed‘ forms of the invention, and >
top of the control reservoir has _a bleeder nozzle
Figs. 9, 10, 11 and 12 are detail views of a modi
‘3|, equipped with a valve, for permitting the es
?ed discharge for the classi?ed pulpyFigs. 11 and cape of air that may collect therein.
12 being sections on the section line 9-.—9 of Fig. 9.
In accordance with the ‘invention, the head of
Referring to Figs. 1 and 2 of the drawings, the
water in the pipe 21 is automatically controlled 50
classifying chamber or pocket l5 has a hydraulic in
response to changes in the density of the pulp
compartment "5 at its base and the customary. in the classifying chamber l5. To this end, a
?ared upper portion I5’. Water is'supplied to
the compartment I6 through a pipe l'l. ‘An-‘ap . stand pipe 32 extends downwardly into the cham
streams of water to the classifying chamber in
accordance with one\of the novel aspects of the
invention,
_
.
.
~
ber I 5 to approximately the level of the spigot 55
..
x
v
'
2,106,126
2
25. At its upper end the stand pipe 32 terminates
in a ?oat chamber 33. The stand pipe is ?lled
with clear water, and the apparatus is so adjust
ed that when the classi?er is in normal opera
tion the level of water in the stand pipe extends
up into the ?oat chamber. Since the density of
of operation of the classi?er is further facilitated
and brought about by maintaining .the velocity
of the upward current of water substantially
constant. The up?ow of water through the
classifying chamber I5 is determined by the head
(:0) of water in the supply pipe l1. Water is
the pulp in the classifying chamber I5 is great
er than the density of water, the level of the
supplied at a constant rate to the pipe |1_as here
inbefore explained. An increase in density of
water (y) in the ?oat chamber 33 will be sub
the pulp in the classifying chamber increases the
10 stantially above the level of the pulp in the
chamber l5.
A ?oat 34 is supported by the water in‘ the ?oat
chamber 33. The ?oat 34 is connected by a chain
35, or the like, with a horizontally disposed lever
15 36 by means of a screw 31 permitting adjustment
in the length of the chain 35. The lever is piv
oted at 38 and counter-poised by a weight 39. A
link 40 connects the lever with a valve 4| at the
upper end of the pipe 21 which extends into a
20 water tank 42 having an over?ow 43 for main
taining a constant level of water in the tank.
Vertical movement of the link 40 actuates the
valve 4| to open and close communication of the
pipe 21 with the water in the tank 42. A water
25 main 46 supplies Water to the tanks |9 and 42
through valve-controlled, outlets 41 and 48, re
spectively.
.
The apparatus is so adjusted‘ that when the
?oat 34 ascends in the ?oat chamber 33 on ac-'
30 count of an increase in pulp density in the classi
fying chamber |5, the link 40 closes the valve 4|
so as to cut off the supply of water from the tank
42 to the pipe 21. In consequence, the escape of
water from the outlet 30 at the base of the con
trol reservoir 26 causes the water level (2:) in the
pipe 21 to descend'with a resulting decrease in the
hydrostatic pressure in the control reservoir. In
consequence, the resistance of the control reser
voir to the out?ow of pulp through the spigot 25
is diminished, and therefore the discharge of pulp
through the spigot is accelerated, and the density
of the pulp in the classifying chamber I5 is de
creased. The link 40 is provided with a counter
weight 44 to decrease its backlash, and insure
45 prompt closure of the valve 4| when the ?oat 34
rises. In order to provide a minimum head of
water in the pipev 21, the upper portion of the pipe
within the tank 42 is provided with a bleeder inlet
resistance to the ascending current of water. 7
This increased resistance causes the head of
water (as) in the pipe H to rise with resulting in
crease in the hydrostatic pressure driving the
current of water upwards, whereby the water
current is maintained at a substantially constant
rate even when the resistance of the pulp in the
classifying chamber increases on account of in
creasing density.
The invention further contemplates an im
proved method of supplying a uniform ascending
stream of water to the classifying chamber. As
illustrated in Figs. 1 and 2, the restricted open
ings or nozzles 2| are provided with caps 22 to
prevent clogging with settled solid particles
whenever the rising water supply may be shut 25
off. These caps 22, by de?ecting the incoming
water, provide initially an approximately uniform
distribution of the rising water over the cross sec
tion of the chamber. The spigot 25 is positioned
a substantial distance above the nozzles 2|, so 30
that the ascending current of water has time to
become uniformly distributed and eddies in it are
destroyed before the water has passed into the
effective classifying zone of the chamber above
the spigot. Furthermore, the position of the
spigot 25 a substantial distance above the nozzles
2| permits the accumulation or building up of a
substantial body of suspended comminuted par
ticles below the spigot, which particles act to
secure a substantially uniform rising current of 40
liquid throughout the cross-section of the cham
ber at the level of the discharge for classi?ed
pulp-
'
In Figs. 3 and 4 of the drawings¢a pair of
water supply pipes I1’ extend laterally into the
bottom of the classifying chamber I5 and each is
provided with a plurality of upwardly directed
45 through which a properly adjusted minimum
50 supply of water ?ows into the pipe 21,from the
nozzles 2|’ covered by a common cap 22'. In
Fig. 5, the nozzles 2| are covered with a rubber
cap 22" having a slot in the top thereof which
automatically closes when the pressure and ?ow
of the ascending water ceases.
maintain su?icient pulp ?uidity for discharge ?ow.
ment of the invention in a classi?er provided with
The spigot 25 is designed with a steeply sloping
upper portion and a vertical lower portion in order
more conventional pulp discharge means. _ The
to prevent the escape of pulp on the lower side of
ment 49, having a perforated roof or cover 50
through which the water rises into the classifying ,
tank 42 even when the valve 4| is closed. This
insures the maintenance of a minimum ?ow of
water to the control reservoir 26 necessary to
the sloping spigot accompanied by the in?ow of
Fig. 6 of the drawings illustrates the embodi
pipe l1 supplies water to a hydraulic compart-V
chamber 5|. Pulp is discharged from the cham
water in the upper sloping portion.
When the ?oat 34 descends in the ?oat chamber‘ ber 5| through the spigot 52 into the control 60
reservoir 53 having a discharge outlet 54. The
33 on account of a decrease in pulp density in the
classifyingchamber l5, the link 40 opens the valve water supply pipe 21 communicates with the res
4| so as to permit the supply of water from the‘ ervoir 53, and the discharge of classi?ed pulp
tank 42 to the pipe 21. In consequence, the
from'the chamber 5| is controlled by the hydro
hydrostatic resistance of the control reservoir 26 static pressure in the reservoir 53 in the same
to the out?ow of pulp through the spigot 25 ‘is manner as in the classi?er of Fig. 1, the same
reference characters designating corresponding
increased, and therefore the discharge of pulp
through the spigot is diminished, and the density elements in the two ?gures.
Figs. 7 and 8 illustrate modi?cations of the in- _
of the pulp in the classifying chamber |5 is in
vention in which irregularities in the density of
I
70 creased.
The automatic control of the discharge of the pulp feed to the classi?er are prevented from‘
classi?ed pulp in response to changes in the affecting the rate of discharge of classi?ed pulp
density of the pulp undergoing classi?cation through the spigot 25.
Referring ?rst to Fig. 7, two stand pipes 55 and
tends to maintain a substantially constant pulp
density in the classifying chamber. Uniformity 56 extend downwardly into the classifying chamber
60
I
2,105,i2e
I claim:
pipes 55 and 56 terminate at their upper ends in
In a. hindered settling classi?er, a ‘chamber
separate ?oat chambers 51 and 58, respectively.‘ in 1.which
mineral particles are permitted to set
Floats 59 and 60 in the ?oat chambers 51 and 58, . tle against a rising current of water and provided
; respectively, are connected by links ‘BI and 62, ‘with a free discharge for classi?ed pulp, means
respectively, to the extremities of a centrally‘ for maintaining\a substantially constant rising 5
pivoted lever 63. The link 6|, near its point of
current in the chamber, a control reservoir com
connection to the lever 63, is connected to the municating with said classi?ed pulp discharge,
chain 35. If water rises to an equal extent in ‘means for establishing a hydrostatic pressure in
the ?oat chambers 51 and 58 the ?oats 59 and said reservoir to oppose discharge of the classi?ed
‘50 do not change their positions, being held mo
pulp, and means for varying inversely the hydro
tionless by the lever 53. Consequently, a uni
static pressure in said reservoir in response to
form ascent of water in the stand pipes 55 and changes in pulp density within the chamber while
[5 to di?erent levels (a and b respectively). The '
55‘does not move the lever 36 (Fig. 1) and hence . maintaining a substantially constant rising cur
does not a?ect the valve 4! regulating the supply
of water to the end of the pipe 21. Since any
' increase in pulp density above the level of the
-
15
2. In a hindered settling classi?er,a chamber in v
which mineral particles are permitted to settle
against a rising current of water and provided
higher water inlet b of the stand pipe 56’ must
cause water to-ascend as ,far in ?oat chamber 58
as in ?oat chamber 59, such an increase in pulp
density does‘ not a?ect the discharge of classi?ed
with a discharge for classi?ed pulp, means for
maintaining a substantially constant rising cur 20
pulp through'the spigot 25. However, any in
nicating with said classi?ed pulp discharge, means
crease in pulp density below the level I) will
cause water to rise to a disproportionately greater -
25 level in ?oat chamber 5]. ~In consequence, ?oat
59 will be forced upwardly, and valve ti (Fig. 1)
will thereby be closed. The closing of valve ti‘
will permit the water level (a) in pipe 21 to fall,
with resulting decrease of hydrostatic pressure
30 in the control reservoir 25 and resulting increase
in discharge rate through spigot 25.
It will be noted that the inlet level of the stand
'40
rent through said chamber.
pipe 55 is at approximately the level of the spigot
25, so that the discharge of classi?ed pulp from
the chamber 15 is controlled by the density of the
pulp from the level of the spigot 25 up to the level
(b) of the inlet of the stand pipe 55. In the
classi?er of Fig. 7, the water inlet nozzles 21 of
the hydraulic compartment 15 are covered with
the slotted rubber caps 22" (Fig. 5).
In Fig. 8 of the drawings, the stand pipes 55
and 5B’ communicate withtthe compartments 5t
and 65 of a diiierential pressure regulator 5'5.
The two compartments are separated by a dia
, phragm 51 to which the chain 55 is connected.
The pressure regulator functions in an equivalent
manner to the lever 53 of Fig. 7, and the appa
ratus operates in substantially the same manner
as explained in connetion with the classi?er of
that ?gure.
.
In Fig. 9 of the drawings, the spigot 25 of Fig. 1
is replaced by a rubber ?utter valve 53. The
classifying chamber l5 has an opening 55 for
the discharge of classi?ed pulp.
The rubber
?utter valve 58 is secured in position over the
opening '59 by a frame ‘ill on the control reser
voir side of the opening. Fig. 11 illustrates the
?utter valve closed by the hydrostatic pressure
in the reservoir 25, and Fig. 12 illustrates the
60 ?utter valve open by a decrease in the hydro
static pressure in the reservoir to permit the dis
charge of classi?ed pulp.
The invention is particularly applicable to the
classi?cation of minerals preparatory to a con
centration operation, such as by Wil?ey Tables
and the‘ like. However, the invention may be ap
plied witth advantage to the classi?cation of any
rent in‘ the chamber, a control reservoir commu
for establishing a hydrostatic pressure in said
reservoir, and means for automatically decreas
ing the hydrostatic pressure in said reservoir upon 25
an increase in the density of the pulp within said
chamber and for increasing the hydrostatic pres
sure in the reservoir upon a decrease in the den
sity of the pulp within the chamber while main- "
taining a substantially constant rising current 30
through said chamber.
a
3. In a hindred settling classi?er, a chamber
in which mineral particles are permitted to settle
against a rising current of water and provided
with a discharge for classi?ed pulp, means for
maintaining a substantially constant rising cur
rent in the chamber, a control reservoir com
municating with said classi?ed pulp discharge,
means for establishing a hydrostatic pressure in
said reservoir, means responsive to changes in the 40
density of the pulp within said chamber, and
means for causing said pulp density responsive
means to decrease the hydrostatic pressure in
said reservoir upon an increase in the density of
the pulp within said chamber and to increase the
hydrostatic pressure in the reservoir upon a de
crease in the density of the pulp within the
chamber while maintaining a substantially con
stant rising current through said chamber.
4. In a hindered settling classi?er, a chamber 50
in which mineral particles are permitted to settle
against a rising current of water and provided
with a discharge for classi?ed pulp, means for
setting up a hydrostatic pressure to oppose the
discharge of classi?ed pulp from the chamber and
means for varying the hydrostatic pressure op
55
posing the discharge inversely in response to
changes in pulp density within a predetermined
height above the level of said discharge and in
dependent of irregularities in the density of the w
pulp fed to the classi?er.
5. In a hindered settling classi?er, a chammr .
in which mineral particles are permitted to settle
against a rising current of water and provided‘
with a discharge for classified pulp, a control 65
reservoir communicating with said classi?ed pulp
discharge, means for establishing a hydrostatic
comminuted ‘solid material and in the appended , pressure in said reservoir, and means for auto
claims I have used the word “mineral” in a gen
70 eric sense to include any solid material suscepti- '
ble to classi?cation by hindered settling. , As is
well understood in the art, other liquid mediums
may in certain cases be substituted for water
without departing from the spirit of the inven
tion.
.
.
'
.
'
.
matically decreasing the hydrostatic pressure in
said reservoir upon an increase in the density of ' 70
the pulp within a predetermined portion of the
pulp column above the'level of said discharge but
independent of changes in pulp density above
said predetermined portion of said pulp column
and for increasing the hydrostatic pressure in
2,105,126
the reservoir upon a decrease in the density of
the pulp within said predetermined portion of
the pulp column.
‘6. In a hindered settling classi?er, a chamber
in which mineral particles are permitted to settle
against a rising current of water, means for in
troducing streams of water into the bottom of
said chamber, means cooperating with the en
tering streams of water for preventing the inter
10 ference of mineral particles therewith, and means
for the discharge from said chamber of classi?ed
pulp positioned above the entering streams of
water a distance suf?cient to permit the substan
tially uniform upward flow of water throughout
a horizontal section of the chamber at the level
of the discharge means.
'7. In a hindered settling classi?er, a chamber
in which mineral particles are permitted to settle
against a rising current of water, means for in
20 troducing streams of water into the bottom of
said chamber, means positioned in the path of
said entering streams of water for de?ecting the
water and for holding mineral particles away
from the entering streams of water, and means
25 for the discharge from said chamber of classi?ed
pulp positioned above the entering streams of
water a distance such that the entering streams
of water attain a substantially uniform velocity
throughout a horizontal section of the chamber
30 at the level of the means for the discharge of
classi?ed pulp.
.
8. In a hindered settling classi?er, a chamber
in which mineral particles are permitted to settle
against arising current of water, means for in
35 troducing streams of water into the bottom of
said chamber, means cooperating with the en
tering streams of water for preventing the inter
ference of mineral particles therewith, means for
the discharge from said chamber of classi?ed pulp
40 positioned a substantial distance above the en
tering streams of water, said substantial distance
being» such that the rising current of water
throughout the chamber at the level of the dis
charge means has substantially uniform velocity,
and means for varying the discharge of classi?ed
pulp from the chamber in response to changesin
pulp density within the chamber.
9. In a hindered settling classi?er, a chamber
in which mineral particles are permitted to settle
against a rising current of water, means for in
troducing streams oi water into the bottom of said
chamber from a supply having a hydrostatic
head responsive to changes in the density of the
pulp in said chamber, means for continuously
furnishing water ata uniform rate to said supply,
means cooperating with the entering streams of
water for preventing the interference of mineral
particles therewith, means for the discharge from
said chamber of classi?ed pulp positioned a sub
60 stantial distance above the entering streams of
water, said substantial distance being such that
the entering streams of water produce a substan
tially constant rising current of water through
out the chamber at the level of the means for
the discharge of classi?ed pulp, and means for
varying the discharge of classi?ed pulp from the
chamber in response to changes in pulp density
within the chamber.
10. The improvement in the hydraulic classi
70 ?cation of comminuted mineral particles by hin
dered settling in a classi?er chamber in a rising
current of liquid which comprises discharging the
classi?ed pulp into liquid in a control chamber
communicating with the classi?er chamber, and
75 varying the hydrostatic head on the liquid in the
control chamber in inverse response to changes
in the density of the pulp undergoing classi?ca
tion by changing the height of a column of liquid
communicating with said control chamber, where
by the rate of discharge of classi?ed pulp into the
control chamber isvaried directly as its density.
11. In a hindered settling classi?er, a classi?er
chamber in which mineral particles are permitted
to settle against a rising current of water and
provided with a discharge'for classi?ed pulp at a.
lower portion thereof, a control chamber ?lled
with a liquid under pressure and communicating
with said discharge, a density-determining means
disposed in said classi?er chamber and responsive
to variations in the density of pulp undergoing
classi?cation, and means for increasing and de
creasing the pressure on the liquid in the control
chamber in response respectively to decreases and
increases determined by the density-determining
means.
12. Apparatus according to claim 11 in which
the
density-determining
means
comprises
a
liquid-containing conduit projecting into and
communicating with the classi?er chamber and
a ?oat supported by the liquid in the conduit.
13. Apparatus according to claim 11 in which
the density-determining means comprises a plu
rality of liquid-containing conduits projecting
into and communicating with the classi?er
chamber at di?erent levels and a plurality of 30
lever-connected floats supported by the liquid
in the respective conduits. ,
14. Apparatus according to‘, claim 11 in which
the density measuring meahsil‘comprise's a con
duit projecting into and communicating with
the classi?er chamber, said conduit being con
nected to a closed chamber having a ?exible
diaphragm that is movable bypa change in pres
sure in the conduit.
15. The improvement in the hydraulic classi 40
?cation of comminuted mineral particles by hin
dered settling in a rising current of liquid in a
chamber which comprises discharging classi?ed
pulp from said chamber into a body of liquid
maintained under hydrostatic pressure and in
contact with the liquid in the chamber, and
varying the rate of 'discharge of the classi?ed
pulp in the chamber by automatically varying
the hydrostatic pressure on the body of liquid
in inverse response to changes in the density 50
oi‘ pulp undergoing classi?cation in'the chamber.
16. The improvement in the hydraulic classi
?cation of comminuted mineral particles by hin
dered settling against a current of liquid in a
chamber which comprises discharging classi?ed ~
pulp from said chamber into a body of liquid
maintained under hydrostatic pressure and in
contact with the liquid in the chamber, and de
creasing the hydrostatic pressure on the body of
liquid upon an increase in the density of pulp (ii)
undergoing classi?cation in the chamber and
increasing the hydrostatic pressure on the body
of liquid upon a decrease in the density of pulp
undergoing classi?cation in the chamber.
17. The improvement in the hydraulic classi 65
?cation of comminuted particles by hindered
settling in a rising current of liquid in a chamber
which comprises discharging classi?ed pulp from
said chamber into a body of liquid maintained
under hydrostatic pressure in contact with the
liquid in the chamber, and while maintaining the
rising current substantially constant automati
cally varying the resistance to discharge of the
classi?ed pulp by varying the hydrostatic pres
sure on the body of'li‘quid in inverse response "
2,105,126
to changes in the density of the pulp undergoing
classi?cation in the chamber.
18? In a hindered settling classi?er, a cham
ber in which mineral particles are permitted to
settle against a rising current of water and pro
vided with an outlet for classi?ed pulp, means
for setting up a hydrostatic pressure to oppose
discharge through said outlet from said chamber,
and means for increasing said hydrostatic pres—
10 sure opposing the discharge upon a decrease in
‘density of the pulp within the chamber and for
decreasing said hydrostatic pressure upon an
increase in density of the pulp within the cham
ber.
-
1
,
19. The improvement in the hydraulic classi
?cation of comminuted particles by hindered
settling in a rising current of liquid in a cham
ber provided with a discharge for classi?ed pulp
which comprises setting up said rising current
of liquid by introducing through an inlet a
stream of liquid into the chamber at a substan
tial distance below the‘ discharge for classi?ed
pulp, said distance being such as to permit the
accumulation of a substantial body of suspended
comminuted particles below said discharge and
l
5
the attainment of a substantially uniform rising
current of liquid throughout the cross-section of
the chamber at the level of the dischargev for
classi?ed pulp, and preventing said suspended
comminuted particles from entering said inlet
when the rising current of liquid is checked.
20. In a hindered settling classi?er, a cham
ber in which mineral particles are permitted to
settle against a rising current of liquid, an inlet
for introducing a stream of'liquid into a lower 10
portion of the chamber, a discharge for classi
?ed pulp from said chamber positioned above the‘
entering stream of liquid a distance such thatv
a body of suspended mineral particles accumu
lates in the chamber below the discharge and 15
causes the entering stream “to distribute itself
with substantial uniformity through a cross-sec
tion of the chamber at the level of the discharge
so that the rising current of liquid is substan-'
tially uniform in the cross-section at said level, 20
and means for preventing the entry of said sus
pended mineral particles into said inlet when the
entering stream of liquid is checked.
JACKSON S.
25
Документ
Категория
Без категории
Просмотров
0
Размер файла
908 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа