Note: Descriptions are shown in the official language in which they were submitted.
1 ~673~9
-2-
This in~ention is concerned ~ith apparat~s for
collecting pollutad liq~ids for separatio~ of ~he
pollutants therefrom.
Tke invention has particular, though not exclusive
application to the cLearing o~ oil from water. When oil
is spilled on water it floats on the s~r~ace to a greater
or lesser eætent dependent upon the relative specific
gravities of the water and of the oil and also upo~ the
extent to which emulsification has taken plaae. Heav~ oils,
which are uear solid and debris, is relatively easily
collected from the water surface but lighter oils are more
difficult to deal with. Of course the greater the auantity
and ~pread of the oil, the more difficult it is to dispose
,of.
here ~ave been major oil spil~dges at sea, as a
result of ship_wreck or oil uell da,mage and the oil 31ick3
escaping have bee~ very large and in some ca~es covering
many square miles of the sea~s surface. Similar problems
also exist i~ inland waterways, pools, lakes or e~en on
tan~ surfaces.
Many solutions to the problem of dispersal or remo~al
o~ oil slicks at sea have been proposed but no one
~atisfactory 301ution has been found, with the rssult that
exten~ive damage to ueighbourlng shore lines and to marine
li~e both above and below the surface o~ the sea ~nd on the
sea bottom has-occurred.
The attempts to deal with the problem of oil 31icks
at sea include spra~ing the 3urface with detergents to
cause the oil to disperse and gink, this, in some cases
causing it to 3ink to the 3ea bed, thus effectively
destroying marine life o~er a large area. ~ide dispersion
often result~ in less pollution ashore, but there i3 gtill
some damage o~er a wider area. It is however generally
accepted that it is better to dispose of the oil while it
673
-3-
is ~till at sea th~ when it has come ashore because the
collectio~ and dispoYal, p~ticularly of heavy crude oils
from beache~ aud the 3hore ls a very difficult task.
C~llecti~g of oil or other polluta~t3 from the sea bed
has not been succes~ful with a~y known sys'em.
The object of thiq i~vention is to pro~ide apparatus
for collecting polluted liquids, such as oil on water, for
remo~al of the pollutants therefrom, in a particularly
effective manner.
According to the present inventio~ there is provided
pumping apparatus ~or collecting p~lluted liquids including
a first pumping stage compri~ing a rotatable ~n~ular rotor
having blades shaped and ar~a~g~d to draw the liq~ids
~wardly ~rom the e~ternal periphery tow~ds the centre o~
rotation, stationasy blades disposed within the rotor,
sX'aped and arranged to æuide the liquids inwardly ~rom
the rotor and 2 further pumping stage having rotatable
blades shaped and ~rranged to deli~er the liquids from the
first pumping stage under pressure to an.outlet of the
pumping apparatus.
Pre~erably the first pum~-ng stage rotor has blades
of part circular sha~e in plar., t;le conve.Y faces o~ the
blades being æenerally outwardl~ t~e rotor and the
blades belng generally inclined to '.~e direction of rotat-
ion, and the stationary blades are also o~ curved shape
with their con~ex faces presented o~posi~el-~ to those
o~ the rotor blades, the stationa~y blades 3eing generally
oppositely inclined to those of the rotor.
Conveniently the further pumping stage blade.; ~-?
cur~ed and of genera'lly part sp-ral form whereby li-~id
entering between these blades in a generally horizonta'
direction, towards the centre of rotation of the sa-d
blade~, is turned through an angle to flow vertically.
~ 167~,19
_4_
In one e~ample the flow from said further pumping
stage is generally verticall~. L~ another e~a~pls the
flow is first vertically and then outwaxdly of the csntre
of rotation, under centri~ugal force.
Con~eniently the p~mpi~g ap~aratus is mounted on a
flotation vess~l by ~eans o~ which the pumping apparatus
can travel across a water surface to collect pollutants
~rom on or under said sur~ace.
The in~rention will now be described by way of eYample
with refarence to the accompanying drawings wherein:
Figure 1 is a cross-sectional side elevation view of
pumping apparatus constructed i~ accordance with the
in~rention,
Figure 2 t3 a diagrammatic view of the rotating and
fixed blades of tile pumping apparatus, though of a slightly
different ver3ion,
Figure 3 i~ a cross-sec~ional ~riew of an alternative
form of the pumping apparatus,
Figure 4 i9 a plan view of the puh~ping a?paratus
qhown in Flgure 3,
Fi3ure 3 i3 a plan view of a flo~a~ion unit car~ylng
pumping apparatus,
Figure 6 ls a 3ide ele~ration view, Fartl~ n 3~ction
of the unit in Figure ; and,
FlO~ure 7 is an end sleva~ion view of the ~nit 3ko~,-n
in Figure ;.
673~9
--5--
~ ig~re 1 shows a pumping apparatus whlch is
intended prima~ily for the collection of polluted water
such as for e:{ample that polluted by oil at sea. FuL~ther
reference will be made to the way ln which this pumping
apparatus is used in particular with reference to ~iO~ure
~ which shows a seagoing .lotation unit on ~Jhich the
pumping apparatus i5 mounted. In order to collect
polluted water the pumping apparatus i 3 set at or just
below the surface 90 that the annular entry which is
~denti~ied at 10 will collect the water in the aurface
reglon.
~ he pumping apparatus includes a stationary casing 11
in which is mounted a central rotary shaft 12. The shaft
is connec~ed for rotation to an electric motor (not shown)
at t3 ~per end. In an alternative the drive may be
by an h;d~aul-c motor directly connected. Xo~e~er an
electric ~o or would have a auitable ge rbo~ containing
a reduction gear. The motor has to be of the full~
immessed type having pro~i3ion to prevent the ingress of
water during use. Carried at the lower end of the shaft
12 is a rotor comprising a di3c 13 mounted on a slee~e
13a which currou~d the lower end of the shaft. Secured
to the outer edge of the disc are b:Lades 14. ~hese
are mounted between rings 1S, 16 and are a~.,led 90 that
as the rotor rotates water is drawn in by tha blades to-
wards the centre of rotation o~ the sha~t.
~ he ring 16 is in a recess in the cas-ng 11 âc that the
entry is defined by the bladss 14. Secured ~o the ca.,ing 11
are stationary 'olades 17 having their outer ?eri~hary
close to but clear from the i~ternal oeriphery of th9
rotary blades 14 on the rotor. ~he ~tationar~ blades l7
are secured at their lower ends to a ring 18 which i3 fi,Yed
to the casing adjacent to the disc l3 with âmall
clearance and serves to guide most of the ~atar t.~rough
the blades in a somewhat upwardly dlrection but orimaril~
1 167319
inwardly towarda the csntre o~ rotation of the shaft 12.
The rotary and stationary blades 14 and 17 represe~t
a fir3t pumpi~g stage of the a~paratus. The blades are so
shaped that the ~low takes place ~enerally inw~rdly and
~igure 2 shows the blade configuration in pLan although
Figure 2 shows a slightly di~ferent version in which the
blade proportions differ from those shown in Figur_ 1. As
can be seen from Figure 2 the blades 14 are of part
circular or other cur~ed con~iguration with the convex
faces presented ganerally outwardly of the rotor. The
blades ~e generally inclined to a radial line so that
each has an outer edge on the periphery of t~e rotor
which is between radial a~d tangential arrangement.
Rotation of the rotor causes the blades 14 to tend to
scoop the polluted liquid inwards and to deliver it to the
spaces between the stationary blades 17. ~igure 2 sho~s the
shap~ of the blades 17 which are part radial and part
cur~ed. rne lnner ends are substantially radial whereas
the outer ends are curved ha~i~g their convex ~aces
oppositely presented to those on the rotor but again
being generally inclined with respect to the radial. In
this example the spacing of the blades i9 at 30 ~ith
re~pect to the axis of rotation~ 12 blades are therefore
~itted. Howe~er in alternati~e exampLes dif~erent numbers
of blades with di~erent ~pacing can be employed.
I'he ~haft speed in this ~xample is app~oximateLy
150 rpm. I~ bLade tip speed is in exces~ o~ a L~redetermined
~alue, turbulence tends to occur which reduces p~mpin~
effici ency . The pumping apparatus is on the contar~
i~tended to draw the liquid inwardly so that radial i~ward
flow results. Thus the effect of centrifugal force crea~es
oDly mechanical stresses ~ithin the material o~ the
rotatiag elements.
The shaft 12 dri~es the rotor d~rectly but there is
a stepdown gear arrangement t~hich dri~es further ~Lades
19. The stepdown ~ear includes an annular gear ring ~0
1 ~67319
a crown wh~el 21 and at least one planet pinion 2~
p~e~erably thres are u~d. The annular gear rin~ 20 is
non r~tatably fixed on the shaft 12~ T~e crown wheel 21
is carried on a rotary stepped sleeve 23 of which in turn
the blades 19 are carried. The blades are ~elded or
pinned to a rotor 24 fixed to the lower end of the slee~e
t~rough a ke~r ~ay and bolts 25. ~he planet pinion 22 or
more than one where fitted are ~ixed in a colla~ 26
secured to tha c~sing 1l by bolts 27. The planet pinion
22 or pinions are mount~d on the ~ollar ~6 through ~
journal bearlng assembly indicated generally at 28 ~nich
allow~ the planet pinion 22 to rotate as the annular
gear ring 20 rotates so that stepdown gsaring occurs to
dr-ve the crown wheel 21 and its slee~re 23 at a speed
in thi3 example o~ between 37~ and 5~0 rpm.
A thru~ bearing 29 is positioned between the annular
gear ring 19 and the end of the slee~e ~3 to accept a~ial
thrust loads. A lubrication ?assage 31 is pro~ided in the
caslng 11 ha~ing a ~ipple 32 at its outer end whereby
lubricant can be pumped into the space containin~ the
annular gear ring 20 the planet pinion 22 or pinion and
the crown wheel 21. The supply of lubric~t can thence
reach the other bearings a~d slae~res.
The sleeve 23 is mounted in a 'oearing 33 o~ ballrace
type situated between the slee~e 23 and the collar 25. On
the shaft is mounted a needle rollar bearing 34 on ~hich i3
~ournalled a seal sleeve 36 and outside thiq a~ln i3 a
~urther naedle roLler bearing 3~ carrled on ~he 31se~rs ~3,
To support this in turn on the fi.Yed collar 26 13 a still
~urther nsedle roller 'oearing 37. ~rilllngs and appropri~te
3paces are provided to enable lubricant to reach the
bearings 34 35 and 37 from the ballbsaring 33.
rne 3eal sleeve 36 carries ooposed lipsaals 33 39
3eparated by a spacer 4l. ~nese llpseals 38 39 engage
1 1~731~3
--8--
on the shaft 12 ~hich in that region is coated with a
ceramic material as i~dicated by 42. This servss to guard
against corrosion and ensures efLecti~enesc of the seal
to prevent ingress of watar to the moving par~q including
the bearings and the gears.
Attached to the rotor 24 carrying the blades 19
is a further seal assembly ~cluding a lip~eal 43 which
also bears on the ceramic surface of the shaft 12.
The roller bearing 37 ~hich is outside the sleeve 23
is also protected from ingress of liquid by a double
sided seal indicated generally at 44. This includes two
compressible rings which are compressed between fi~ed
surfaces and re~pecti~e movable parts of a split ring 45.
Th~ blades l9 are o~ part spiral shape there being
i~ this exa~ple 6 such blades. These blades have their
outer peripheries close to but spaced from the inner edges
of the statlonary bi3des 17 and accept the liquid therefrom
~lowing in an inward direction. The blades 19 cause the
~low of liquid to be changed in d-rection ~rom radially
inward to axially upward flow. At the same time they impart
pressure to the upwa~d flow the blades 19 rotating faster
thar~ the rotor blades 14 by virtue of the stepup gearing
as explained.
The liquid leaving the upper edges of the blades 19
flows through an outlet duct 46 at the top of the casing.
This i~ connected to an appropriate manifold (not shown)
which carrie~ the liquid away to an appropriate point at
which it may be filtered or otherwise processed to remo~e
the pollutants.
The shat't 12 has a further ballbearing 47 and an
adjacent seal 48 ad~jacent to the upper snd, 'hls being
secured by a co~er plate 49. rhe lower end of the shaf~
is encLosed by a further cover ?late ;l and in the diac
13 there is a drain plug 52.
1 1673~9
g
- Referring ~o ~iguse 3 this shows a pumping apparatu
similar to that of Figure 1 w-th the exception o~ the
outlet arrangements. Similar numerals are used for the
same components where appropriate. ~hus a central shaft
12 carries a rotor including a disc 13 and blades 14.
Within these are stationary blades 17 carried on a fi~ed
casing 11. ~ second stage of the pumping apparatus is
provided by blades ;3 carried on a rotor 54 which is
dsi~en through stepup gearing from the sha~t 12. ~he
stepup gearing includes a first gear 3~ which is æcured to
the shaft 1~ meshing with a gear ~6 on a short sha~t 57
parallel with the shaft 12. Also mounted on the shaft 57
is a larger gearwheel 38 meshing with a gearwheel ;9
engaged around but not rotatable with the sha~t 12. The
gear j9 is secured by screws 61 and a keyway to a slee~e
62 carrying the blades 53 of the second -~tage. ~he slee~e
62 i3 mounted in needle roller beasin~s 63 and 64
between which i~ a sealing a3sembly similar to that
identi~ied by numeral 44 in Figure 1 and including
two re311ient rings and a split ring 43. Within the
31ee~e 6~ are further needle roller bearings 65, 66
whlch carry a further sleeve 67 to which is connected
an exten3ion 68 of the stationaxy casing 11. rhi3 e~tension
68 carries the lower end3 of the stationar~ blade 17.
The blades 33 are not welded to the rotor j4 but instead
are adjustable relati~ely thereto by means o~ a mechanism
(not shown), ~he mechanism includes pivots on which the
respective blades 53 ars carried in the ro~or 3!1 a~d a
locking arrangement whereby each blade can be adju3ted
relatl~e to the rotor. Calibration marks are pro~lde~
to enabie all the blades ~3 to be adjusted to the Yame
extent .
The blades j3 ha~e a di~ferent shape fro~ the blades
19 in that they extend upwardly to a greater exter.t and
their upper edges are inclined outwardly and downwardly
as shown. Otherwise t~e blades ~3 are of the same part
I l 67319
_ 10 -
axial
spiral form so that the liquid i9 delivered in an upward/
direction. ~bove the blades 53 thers are blades 69 ~orming
a further pumping stage which i3 a centrifugal pumping unit.
The blades 69 have backward curvature to the direction of
rotation. T~e blades 69 are ~ixed onto the rotor 54
and rotate at the same speed as the olades 33. They ars
also of narrowing section. The liquid is delivered into a
volute shaped chamber 71 which at its outer larger end
discharges into a pipeline or other means for carrying away
the liquid. A flange 72 is shown in Figurss 3 and 4 for
such connection. The shape of the ~olute i9 clearly seen
in the plan view of Figurs 4. The blades 69 increase the
press~rs of the liquid to deliver it in the voluta 71
continuously.
A rgmovable cover 73 at the top of the apparatus allows
access to the gearing repr9sented by the ~ears S5,56,58,S9.
However in thi~example the bearing 47 and seal 48 are
attached to this cover 73.
In another example of pumping apparatus (not shown)
the further or second stage of the pumping apparatus ia
a helically bladed lift pump aituatea in the centre of
the apparatus and there is a central outlet for the mi~cture.
Referring to Figures 5, 5 and 7 there is ~hown a
seagoing flotation unit which has mounted on it ~ pumping
s~fstem comprising two pumping apparatu~ of t~s kind previously
described. One of these i3 identifisd by numeral 73 in
Fi~r9 j. These apparatus ars mounted side by side a~d
have respectiv~ outLets, one of ~hich is 3hown in ~iæurs
at 74, These join into a common outlet pipe 75 prefsrabl~
of flexi'ole type for the delivery of the collscted mi:cture
to an a~sociated vessel.
~ he flotation unit is intended to be towed by an
attendant ves3el and in one exampls it is attached by
cables to the side of the vessel. .~ suitable cable
1 16~3~9
arrangement is by springing which involvss attachment at two
spaced positions on the vessel and on the flotation unit,
the forward cabla being trailed from the flotation unit
to the vessel whereas the a~ter cable is trailed from t~e
vessel to the flotation unit. This springing arrangement
ensure~ that the flotation vessel will be towed in a
straight ahead position. However the flotation unit may
be towed in any convenient way beside a vessel either
forward or a~t or amidships or it may be provided with its
own motor driven propeller so that it is self propslled.
For the attachment of towing cables there are four
attachment points at 76, 77,78, 79.
' The unit compri3es an inflatable generally U shaped
structure having two forwardly directed divergent arms
8lj 82 and a connecting portion 83 which ~urrounds the
pumping syste~ and forms the rear of the f~otation unit.
The inflatable structure is made up of two circular
section inflatable bags of similar configuration and
secured together by strapping, indicated particularly
at 84 in ~igure 7. rhis ~trapping is preferably rubber
or rubber liXe material and is bonded to the bags to
~ecure them together. The bags have respective inflation
pOints (not ~hown) whereby they can be independently
in~lated to a required degree. The degree of inflation
go~erns the height at which the flb'ation unit rides in
the water. Water level i9 indicated a~ 3~ in ~igures 6
and 7 but thia may vary according to condi~ions such as the
height of wa~es through which the unit i9 passinæ. In
general the rougher the sea the deeper the unit ~hould
ride in the water but the height of the pumping sy~tem
is also important and buoyancy may be varisd to con~rol
the le~el of the inlets of the pumping apparatus in
accordance with the level of material to be collected from
the sea surface.
In particular the ~y~tsm is intended for the collection
- ~ 3 ~73~9
_. 12 -
of oil from the surface of the sea but oils vary in
densit~ and t~erefore in the level in which they float
at or below t~e water surface.
For further stabilising the unit in the water ther~
is a cross bar ~6 extendin~ acros~ the front o~ the unit
betwee~ the two arms 81, 8Z o~ the in~latable s~r~ct~r~
t~i~ ba~ carryl~g adJ~stable ~a~es 87 one of which i~ seen
in c~oss sectio~ i~ ~igur~ 6. Air~oil section in place
of the n~rrow elliptic~l shape may be used. The cross
bar 86 is secured to the in~latable structure by ~trappin2
88 which is iecured to the inflatablé with suitable fl0xibla
reinfo.rcement which may be attached by appropriate
adhe~ives .
F~-~ th~r stabili~ation o~ th~ unit i3 achieved by the
attachment OX sea anchors to one or more of t~e rings 89
on the undornea~h of the in~latable structure. These
ringa may be attach~d by rein~orced patches gl secured by
adhesi~e to the strapping 84 of the in~lat~bls struct~re.
A sea anchor comprises a cyl~drical b~cket-like structure
u~ually made of canva~ with a hole in the bottom through
which wat~r can flow but which restrict~ movement of the
sea anchor and th~refore of th~ flotat'on ~nlt to which
it i~ attached by offerlng resistancs to the out~low o~
water. Other ~orms o~ sea anchor may be provided.
To a~lst in the forward tra~el ~tability of the
un~t thsr~ are two re~ractable plates 92 containsd in
~lottsd structures 93. Th~ platas 92 ars hingsd a~
and are attached by cables 9; to a control 96 ~h9reo~r
the plates 92 can be raised and lowered as requirsd.
3etween the two arms 81~82 of the inflatable structure
is mounted a ~71atform 97, This is slotted at 98 over its
surface~ the 310ts being rearwardly and downwardly i~clined
so that a first separation of oil from water ta~es pLace
~673~.9
_ 13 _
by allowing ~he le~s d~nse water to flow through the slots
underneath ~he unit. The platform is attached to a
cross bar 98 which extends between the ar~s 81,82 o~
the in~latable structure and i3 secured at its ends by
reinforced patc~es 99 to the strapping 84 of the structure.
A cross bar 98 carrias three swivel structures 101 whic~
ars at~ached to the plat~orm 97 through reinforcing bars
102 and U bolts 103. The platform i3 therefore able to
swivel about the axiC o~ the cros3 bar 98 and such swivel~inO
is-controlled by respective hydraulic pi3ton and cylinder
unit~ 104,105 which are situatad near the ~ront and rear
re~pectively of the platform. These are controllsd in
any convenient way from a remote position. The Sront of
ths plat~orm enga~es in the rear end of a guide blade
106 whicn is also fi~ed by cross-member 107 extending
transvsrsel~f of the unit .
~ t the rear of the platform 97 i3 a weir plate 10g
and behind this in tu - n ig th~ structure 111 on whioh
the pumping apparatus is mounted. Thi3 is made up of
rein~orcsd plate~ which define a gener~l box 3tructure
forming a sump which however has ~ front opening adJac~nt
to the weir plate 1G9 to accept the inComing flow of oil
and wat~r mixturs, A r~ar wall 112 forms a baf~l~ between
th~ ar9a 3urrounding the pumping iy~tem an~ ths connoctin~
portlon at tho r~ar o~ th~ ~lota~ion unit, ~ound the
s~o and rsar o~ th~ platform 97 is a fl~xible i~latable tube
forming a ~eal to ~eve~t water ~lowin~ bet~isen the platform
and the inflatable structure at an~ angLe of t~e ?latform.
Beneath the pumping system are rsinforcqment platei
113 which as sesn in Figure 6 have lightening holss and
~hich serve to support a plate 114 beneath the pumping
system ~hich forms a floor to that compartment. Beneath
the plat~orm g7 is a further plate 113 havin~ its forward
end adjacent to the 3uide blade 106 and ~avin~ its r~ar
end spaced below the forward end of the plata 114. T~us
3 t 9
4 --
a transverse slot 116 is formed, through which watar
flowing through the slots in the plat~orm 97 can escape
underneath the unit. Dther weir plates (not sho~n)
may be attached to the platform to assi3t water dispersion.
Above the pumping apparatus there may be fitted a
transparent canopy 117 which forms a weat~er protection
against an operator riding on the flotation unit. The
control 96 ~or the plates 92 and also appropriata hydraulic
controls for the platform inclination 97 as well as for
the vanes 87 may be situated within the canopy, Also it
is possible for the operator to wor~ upon the pumping
apparatus as required. Oil supply for operation of such
dsvice3 may be obtained directly from the attendant vessel
or a manual 3ystem may be provided.
~ To ~ra~ any large debris which may be floating on ths
surface of tha w3ter and to prevent it entering the pumping
apparatus a scrsen 11~ may be attached to an arm 108
on the inflatable 3tructure.
Thls apparatus is intended ~or 3eagoing use but where
a 3imllar flotation unit i9 required for inland waterways
a 3impler flotation unit may be provid~d. Tnis has only
one inflatable bag and it does not require the buoyancy
and directional stabilitr controls which ar~ necessary
on the seagoing version. Buoyancy heighl i5 ~imply
controlled by the degree of inflation of the ba~.
It is aLso possible to mount pumping apparatu3 o-
~simple flotation ring. This is a suitable arrangemen~
where the equipment is to be used for example on a wellhe~
or other pool ~hers forward travel of the unit across the
surface is not required. In 3uch a static position it
may not be neCeSsa~J to have a flotation ring at all but ~he
unit is 3imply suspended by cable3 from a srane or other
~ 3673~9
structure, the depth of immersion being determined by the
depth o~ the liquid to be collected.
~ ny collsct2d liquid may be carried away to any
convenient storage or filtration plant. For example in
the seagoing version the collacted mi~ture may be taken
to a barge or other ~torage vessel which may or may not
be the attendant vessel used for towing the flotation unit.
The ~iltration to separate the oil from the water may be
carried out on such vessel or at some other place. For
the collection of oil on the surface o~ the sea over a
wide area it is pos~ible to provide a series of the
flotation units each with pumping system to travel over
the 3urface of the sea in extended line and in this way
substantia1 oil 31ic~s may be collected.
The oil and water mi~ture may be pumped directly into
barges. The liquid e~tering the pumping zone is preferably
treated with a 9plitter or emul~i~ying chemical, which is
convenisntly metered into i ~ectors and when the liquid
ha~ been allowed to settle in the barge ~or appro~imately
20 mlnutes qeparation occurs 90 that wat~r can be pumped out,
