Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~EC.ll '05 16:E15 ~ 'URERIJFh'~ L~l`J~OII P.05
~33~59
Sep~rator Drain BoxeF
The pre~ent inven~ion xelate~ to ~,eparator dr~ln
boxes, and concern~ more particularly, but not e~clusively,
drain boxeF ~r Beparator assemblie~ u~ed ~th ~a~
turbineF, i'ox 1andborne or marine applicAti~n~,
It i~ common for en~ines o~ the ga~ turbine
variety to have f11ters at their air intakes. The~e
iilter~, not only get rid o~ potentially damaging solid
particulate matter, tbey can alæo remoYe exce~s water
(even ln Yapour ~orm) ~rom tbe air. An ex,~mple o~
a ~y~tem emplo~iDg such a filter i6 described in the
Speeiflcation o~ oux European Patent Application ~o.
83~300,521.8 (Publication No. 0,087,229)l one embodlment
o~ which takes the form of a tube or duct lnto which
is drawn the air to be filtered, whlch tube contaiDs
a number of ~iltering components includlng pads o~
knitted mesh and a series of zlg-~ag va~es. These
vane~ remove any entrained water dropletF, that have
got thi~ farl and the "conden~ed" water run6 do~n the
vanes (under gravity) into what i~ known as a "drain
box", ~ro~ which it is led away and dispo3ed o~. The
present invention proposes a nov~,l de~lgn o~ drain
box th~t guite eigni~icantly ilsprove~ the per~ormance
~ois~ure separatlng devlce~ by incorporatlng a ~ore
efiicient system of drain water ~nd ~olids remoYal,
2~, and by providing for a more e~icient alr ~low throu~h
the filter as~embly.
~ oi~ture ~eparators can carry a very hlgh water
loading. However, the upper lim~t o~ water-carrying
capaci~y i~ normally de~ine~ by the re-entrain~ent o~
30 large drop~ OI ~pray ~rom the drain box at the bottom
o~ the moi~ture separator. This re-entrainmen'c i~ ~ore
marked at hlgher velocities, thereby con~iderably
reducing the water-handling capabillty of the ~ep~r~tor
a~embly. lt i~, there~ore, ~ery important to de~lgn
. ... :
r.
.2~331D~i9
the ~rain box ln such a way QS to reduce~or even
elimillatç, re-entrainment over the range of oper~tlng
velocitie~, ln ~dditlon to lmprovlDg the dralnlng o~
water and solids from the drain b~x.
In one cla~ic design o~ currently~available thre~-
stage separator a~semb~y system (like that o~ the
aforemention~d European Application, ~or in~tance~, ~h~
vane~ bottom on a ledge in the dr~in box, above the
drain box floor, leaving a gap between the bottom oi
the vanes and the floor of the dr~in box. Re-entrainment
i5 reduced by having moisture and solid~ drain irom the
vanes into the drain box for disposal thr~ugh a dra~n~ng
means at the bottom o~ the drain box. However, un~or-
tunately the gap formed in the space between the bottom
15 of the vanes and the floor o~ the drain box does not
offer signi~icant resistance to the air ~low, ~nd as a
result the gap becomes a major ~ource o~ re entrainment
of moisture laden air into the ~ilter air flow, thereby
diluting the ~iltering effect of the separation a~sembly.
In one proposal to correct this re-entralnment
problem, the drain box is packed with a knitted me~h
material (made of type gO35 "~IT" polypropylene, ~or
e~ample). However, this packing "~olution" introduce~
: a new, and more significant~ proble~ in that a drain
2~ box wlth packing collect~ Elnd r~tain~ the corroslve
eolids dralnlng ~rom the vanes, causlng ~ loading o~
d~ rt and ~alt sollds in th~ packin~ n~aterial and drain
box trougl~, and inhibiting the e~icient drAin~n~ oi
the drain box. In turn, the l~ck of proper drainl~g
~orces ~re~uent cleaning and maintenance oP the drain
box~which ls a difficult tas~ due to the inefiicignt
desig~ o~ the box. These ~actox~ lead lnevltably to
ext~.nsive cvxrosion of the dr~in ~ox, and ultlmat~ly
to possible structural ~ailure.
Thls problem - what to do to ~top air pa~si~g
through the gap between the va~e bottom and drain
~'r ~ ïvl b' I 1 ~ ILl~ H,' LO~ 0l~1 p. 07
L2~33~)~;9
--3~
box ~loor - ha~ be~3et ~epar~tor a~embly de~igner~ Por
some years, and as yet no "solution" (cuch a~ the knltted
packing one mentioned above~ ha~ proved ~ati~i~ctory.
T~e present invention, thoughJ doe~ provlde such a
5 ~atisfacto~y solution - and, ~oreover, by what ~eem~ ~t
I:lr6t sight to be a minor chAnge ln the deslgn o:E the
vane/drain box portion o~ the a~sembly, yet wh~ch tur~s
out to be o~ major ~ign~flcance~ It 1~ amazingly
simple: ln the present invention, the v~ne~ utllized
in the separator a6sembly to remove airborne w~ter vapour
or droplets are extended to the f loor o~ the drain box
ln intimate contact wlth the dra~n enclosure bottom
sur~ace. Extending the vanes of the drain bo~ floor
~n this way provides additional structural vane ~upport,
and re8ults ln a ~tronger, m~re rigid filter system,
All need for knitted mesh or other p~cking material~
is elimi~ated, providing ~or no retention o~ corro~ive
solids, ior e~e o~ ~lushing and maintenance, and ~or the
virtual eliminatlon of corrosion leading to ~tructural
~ailure~
In one aspect, there~orel thi~ invention provide33
in a ~eparator o~ the kind described, the use o~ v~nes
which e~tend all the way ~o the ~loor o~ the drain box.
Appart from the extension o~ the vane~ into
contact with the drain bo~ floorl the a~sembly may be
of any type, conventional or otherwi~e. Speci~ically, ,
the dr~ mean~ (the actu~l draining vents via
~h~ch collected moisture/dirt i6 removed from the drain
box~ may be dlrectly under the vane~. ~owever, ir~ a0 particul~rly preferred embodlmen~ the matter is arr~nged
htly ~i~ferently, and there is pro~lded, in a
dlrection down~tr~m OI the vanes~drain box combination
proper, an exten~ion of the bosc (re.ther like ~ boot~trunk
o~ a Dlotor car) whi ch i~ not part of the passageway by
35 whlch the Iiltered alr ts fed on and Qu~ ~f the as~emhly.
L ~ . 11 13~ lt~ Ut~t~llUr H;~ L.SI`il)lJI l P . 0~
~L2~33~ ;9
--4--
.
This extension, or drain cha~ber, 1~ open to the
box proper, but closed to the r~st o~ the a~se~bly, ~nd
the dr~ining means, or vent~, ~re po~ltloned ~ithin tbe
chamber - thu~ dowrstream of the vanes rather than
dlrectly beneath the ~anes themselves.
The e~lciency o~ the i'low o~ air through the ~iltcr
o~ a ~y~tem incorporating the present invention i~ not
negatively a~fected a~ in the previou61y~de0crlbed
: three-~tage ~ystem utilizlng a drain box with an air gap
below the vanes. In the present invention, air flow
through the bottom o~ ~he vanes and the drain box wlll
take a longer ~low path having greater re~l~taDce to
~low than the ~low of air through the ~ilter. Conse~uently,
the ~low o~ air will be contained within the ~ilter ~lth
a re~ultant greater efficiency due to the elimlnation o~
re-entralnment. The mo~t ~igni~cant ~actor, however,
i6 the abllity of a separator ~abricated with the
present inYention to per~orm eonsistently, as described
herein,over the entire operating ran~e o~ the moisture
3epar~tor,
A particularly beneficial advantage of this
draln chamber idea i~ that a~ integral drain box
wa~hdown system ~ay be incorporated to provide, ~or
example, a multipIlcity of ~lushing por~, a remov~ble
drain box trough, or a combination o~ both. The
: ~a~hdown system proYides a means of ~lushing the
drain chamber o~ debrls and corro~ive particles nor~ally
retained by ~y~temx having drain boxes with packlng,
and by ~ystems not lncorporatir~g the drain box feature~
3~ o~ the present inventlon. The descrlbed Plushlne ~ature
oi thi~ invention prevents excessive corroslon in the
~rea moBt pro~e to galvanie and chemicRl ero~ion.
The improved separator assembly o~ the invention
allows a ~re~ unimpeded ~low o~ drain ~ater and
35 ~u~pended sollds to the draln port~ in the draln box
exten~ion. l~e drain port~ may be amply proportloned
`- ~2830S9
--5-
~o accept the ~ull dr~inage ~low regardles~ o~ the
relatlve position of the sy~tem with xe~pect to the
horizontal plane. By way o~ example, ~hen the sy~tem
18 i~talled in a ~ea-going ve~sel, the ship's pitch
or roll does not a~ect the operation o~ the d~ain
connection~ or i~pede their flo~ capabilities,
The drain chamber ln the preferred embodiments
of the lnvention i~ located downstre~ o~ the van~ bank,
~nd in thi B way is capa~le of providlng ~ tull,
unobstructed, area ~or the ~ree ~lvw o~ the drain water,
This drain chamber also provides an excellent means o~
preventing partlcle re-entrainment, as can occur in
other moisture separation dev~ces, by having a large
uni~peded ~low area ~or ~ull drop of~ ~nd capture o~
particles,
The design of the drain box of this invention
can also provides a supplementary means o~ ~tructural
integrity by enclosing the ~oisture separation sy~tem
in a semi-mon~que enclosure to e~hance the shock and
vibratlon capabilities o~ the complete sy~tem.
The separator assembly of the present inventlon
provides for greater flexibility in the ~anner o~
~lu~hlng the dr~in box, utilizlng (at lea~t in it6
pre~erred embodiments):-
a multipliclty of flushing ports loc~ted in one
or more locations in the top, ~nds and~or sides
o~ the drain box or drain box extension;
a ~lu~hing o~ the drain box with ~resh water,
~aturated steam or iresh ~ater ~nd 6aturated steam
in comblnation;
a ~anu~l ~lushing oi the drain box through ~lushlng
port~ u~ing:
i) hand-held ~lexible hoses or plpes, and/or
li~ hand-held rigid lances inserted through port~;
an automatic flu~hing o~ the drain box ~ith ilexible
L,'L~ ' L~ 1 .CI I 1 c,~lr~c~r~lr ~ L~JI IL~ P. 10
83059
--6~
or rigid line~ temporarily or permanently attached
to ~elected fluRhing ports, oper~ted by any o~
a variety of manual or autom~tie timing deYice~;
any combina~ion o~ ~lu~hing ports, manual operatlon,
~utomatic ~per~tion, fresh water flushing, ~turated
steam ~lushing, through permanent or ~emporary
connectlons to any of the ~lushing ports, to
accomplis~ the desired el.iminatioD of unwanted
debris o~ salt and solid particles from the drain
box or drain box extension.
The de~cribed preferred flushing system o~ the
present invention will ellminate unwanted de~ris by
di6sDlving the ~alt particles and utilizing the
washdown ~low velocity to dislodge the remaining
undis~olved debris. The movem~nt of this ~ u~hing
~low o~ water and debris is channeled.into the
existing drain connections of the drain box or drain
box exten~ion. This ~lush and drain feature i~ uni~ue
in that it is not available in any other ~oi~tùre
separation sy~tem, but is exclusively available in
that ~f the present invent~on.
The present inve~tion provldes a ~eparator
assembly having an improved~ mor~ eff~clent air ~low
through the vane bank; an i~proYed, more ef~ici~nt
syst~m or di~solving and/or flu5bing sol~d6 and salts
from the draln box; and an lmproved, mor~ efiicient
drain water ~nd ~olids removal SyBtem ior draini~g
such water and solids from the drain canal of the
dra~n box ~nd drain ~ox exten6ion.
133059
According to a broad aspect, the invention relates to
a drain box for use in a gas turbine separator assembly wherein
the drain box is mounted below a duct of
the separator to receive vanes passing through an upper
region of the drain box to contact the base thereof, and
~ comprising a plurality of flushing ports which allow
: cleaning substances to be flushed through the drain box
in order to remove particles of matter collected therein.
Qne embodiment of the invention is now described, though by
way of illustration only, with reference to the accompanying
Drawings, in which:-
Figure 1 shows a diagrammatic vertical cross-section through
the final stage (the vane/drain box section) of a
separator assembly of the invention; and
Figure 2 shows a diagrammatic top plan view (partly in section)
of the assembly of Figure 1.
.~
~,~...1l ~ l tl: C~ H~ 1,>~ Ll.Jr~ P.lc~
~l2~33~S9
-B-
The .vane~dxai~ box section o~ the ~eparator
assembly o~ ~igures 1 and 2 compri6e~ a duct (only the
duct ~loor 11 - the lower edge/6urf~ce - is shown)
at or near the downstre~m end o~ which is an array o~
vertical vanes ~12). The vanes extend below the botto~
o~ the duct floor il and into a "clo~ed" drain box
(13) that is sealingly mounted on the und~r~ide o~ the
duc~ ~loor; the v~nes extend into actual contact (at 1~)
with the bottom of the drain box.
The drain box 13 has a rearward extension (15) lnto
which ~lows the water (not shown) drainlng o~ tbe vane~
12, and at the bottom of this extension is a ~eries ~i
draln pipes (as 16; only two are here shown) through
which the water may be lead o~ and disposed o~. The
box's rear extenslon 15 also has, ln its upper and
side ~urfaces, a series o~ plugged ~lushing ports ~us 17)
through which water, steam and so on may be forced ln
to help clear the box o~ any solids (dirt or ~cale)
lodged therein.
