U.S. patent application number 09/875527 was filed with the patent office on 2002-12-12 for dry cleaning method and device.
Invention is credited to Taylor, Robert E..
Application Number | 20020184715 09/875527 |
Document ID | / |
Family ID | 25365958 |
Filed Date | 2002-12-12 |
United States Patent
Application |
20020184715 |
Kind Code |
A1 |
Taylor, Robert E. |
December 12, 2002 |
Dry cleaning method and device
Abstract
An improved dry cleaning apparatus and method for the
non-aqueous cleaning of fabric materials comprises the introduction
of steam into a dryer chamber containing fabric materials
previously washed in a non-aqueous organic cleaning solvent such as
perchloroethylene. The steam is heated at a sufficient temperature
for a duration of time, both of which are determined by the type of
fabric and solvents involved. The heated steam volatilizes any
excess cleaning solvent contained in or on said fabric creating a
gaseous water/solvent mixture which is then subsequently separated
from the fabric materials. The gaseous mixture can be condensed,
its component parts separated and re-used in the cycle again.
Inventors: |
Taylor, Robert E.;
(Irvington, NY) |
Correspondence
Address: |
Craig M. Bell
1704 Jennings Way
Paoli
PA
19301
US
|
Family ID: |
25365958 |
Appl. No.: |
09/875527 |
Filed: |
June 6, 2001 |
Current U.S.
Class: |
8/142 ; 510/285;
510/286 |
Current CPC
Class: |
D06L 1/08 20130101; D06L
1/02 20130101; D06F 43/007 20130101 |
Class at
Publication: |
8/142 ; 510/285;
510/286 |
International
Class: |
D06L 001/04; D06F
001/00 |
Claims
What I claim is:
1) A method for the cleaning of fabric wherein a non-aqueous
organic cleaning solvent is used to clean said fabric further
comprising the application of steam to said fabric during the
drying cycle.
2) The method of claim 1 wherein said steam contacts said fabric at
a temperature and for a period of time sufficient to remove any
excess organic cleaning solvent embedded in or on said fabric
materials.
3) The method of claim 2 wherein said steam volatilizes said
organic cleaning solvent thereby forming a gaseous water/solvent
mixture which is subsequently drawn away and separated from said
fabric.
4) The method of claim 3 wherein said gaseous water/solvent mixture
that has been separated from said fabric is cooled, condensed and
further separated into water and solvent fractions.
5) The method of claim 4 wherein said cleaning solvent is
perchloroethylene.
6) An improved dry cleaning apparatus for the non-aqueous cleaning
of fabric materials comprising: a) an internal drying chamber; b) a
steam source; c) a conduit for the introduction of said steam into
said drying chamber; and d) an exit means for the removal of said
steam from said drying chamber.
7) The improved dry cleaning apparatus of claim 6 wherein said
drying chamber is of sufficient size so as to contain a plurality
of said fabric materials which have been contacted with a
sufficient amount of non-aqueous, organic cleaning solvent prior to
said fabric's introduction into said chamber.
8) The improved dry cleaning apparatus of claim 7 wherein said
chamber conduit introduces said steam at a suitable temperature and
for a time sufficient to volatilize any excess organic cleaning
solvent remaining in or on said fabric materials resulting in a
gaseous water/solvent mixture that becomes separate and apart from
said fabric material.
9) The improved dry cleaning apparatus of claim 8 wherein said
conduit further comprises a valve for the control of the release
and stoppage of the introduction of said steam into said drying
chamber.
10) The improved dry cleaning apparatus of claim 9 wherein said
valve is a solenoid valve operatively connected to a timer device
for the selective durational control of the introduction of said
steam into said drying chamber.
11) The improved dry cleaning apparatus of claim 10 wherein said
timer device is electronically connected to said solenoid valve for
the selective durational control of the introduction of said steam
into said drying chamber.
12) The improved dry cleaning apparatus of claim 9 wherein said
valve is manually operated.
13) The improved dry cleaning apparatus of claim 11 further
comprising a manually operated shut off valve.
14) The improved dry cleaning apparatus of claim 13 wherein said
exit means comprises a second conduit in communication with said
dryer chamber operatively connected to an exhaust or vacuum
fan.
15) The improved dry cleaning apparatus of claim 14 wherein said
exhaust or vacuum fan draws said water/organic solvent mixture from
said drying chamber and deposits it in a secondary chamber wherein
it is cooled and condensed.
16) The improved dry cleaning apparatus of claim 15 wherein said
water/organic mixture is separated after condensation into its two
component parts for re-use.
17) The improved dry cleaning apparatus of claim 16 wherein said
fabric materials are clothes, linens, sheets, blankets, rugs,
carpets, draperies, coats and mixtures thereof.
Description
METHOD OF THE INVENTION
[0001] The invention relates generally to methods for dry cleaning
textiles and clothing. More specifically, the present invention
relates to a dry cleaning apparatus and modifications thereto which
removes excess dry cleaning solvent from the system and is thereby
more environmentally friendly.
BACKGROUND OF THE INVENTION
[0002] Dry cleaning of textiles and, in particular, fine clothing
is a well known process in which the garment is immersed in a
cleaning solvent other than water which loosens any dirt, grease or
grime from the fibers of the garment fabric which is then, in one
way or another, evaporated off. There are any number of different
solvents and methods for doing this.
[0003] In conventional dry cleaning systems, the effluent vapors or
fumes of the solvent such as perchlorethylene (PERC) emanating from
the dry cleaning washing machine and dryers generally are vented
directly to the atmosphere and thus pollute the atmosphere. By
being so vented, they are also lost for reuse. Thus, the escaping
vapors not only produce an environmental hazard, but their loss is
extremely costly to the dry cleaning establishment.
[0004] Attempts have been made to remove the solvent vapor
contained in the air-stream through a bed of activated carbon. The
carbon absorbs the solvent vapor or gas held in the air-stream,
allowing the thus cleaned air to pass through the carbon bed to
atmosphere. See U.S. Pat. Nos. 3,203,110 and 3,538,615 to Fuhring
et al. Unfortunately, the carbon bed will only absorb approximately
one gallon of solvent per 80 lb. of carbon before becoming
saturated with solvent vapor, and must then be de-absorbed by
passing a "blanket" of steam through the carbon bed in a reverse
direction to that of the absorption flow. The steam and solvent
vapors form an azeotrope which must then be condensed, and the
resultant water and liquid solvent must be separated according to
their specific gravities. Thereafter, the solvent may then be
recycled for reuse.
[0005] U.S. Pat. No. 4,622,039 to Merenda discloses and claims a
method and means to recapture the cleaning solvent and to reuse the
same so that as a result thereof, the solvent is not vented to the
atmosphere and thus pollution of the atmosphere is avoided. A dry
cleaning washer and a dryer are arranged in a closed cycle system
so that the effluent solvent vapor from the washer is delivered to
an accumulator chamber simultaneously with the delivery from the
dryer of effluent hot air. The hot air superheats the solvent vapor
thereby increasing its volatility and the heated and highly
volatile solvent vapor is then passed to a condenser which contains
feed coils for supplying clean air to the dryer. In passing through
the condenser, the superheated solvent vapor instantly liquifies
giving off its heat to the cool air, thus pre-heating the clean air
prior to its entry into the dryer. The liquified solvent is
returned to the washer, or to a storage reservoir.
[0006] U.S. Pat. No. 3,951,597 to Mooring discloses and claims a
method of dry cleaning fabrics, draperies or clothing, in situ, by
forcefully infusing the fabric in the open atmosphere with special
fast-acting, versatile dry cleaning solvent so as to dissolve and
suspend various stains and soils in the fabric, even though firmly
set due to age. Ambient air is promptly drawn in and droplets of
soil-laden solvent is promptly drawn therethrough by suction into a
closed waste and suction chamber where the soil is deposited in the
form of a sludge, while the carrier air and solvent is discharged
to the atmosphere. A special, highly effective, fast-acting,
non-flammable and non-toxic solvent such as methylene chloride,
trichloro-ethylene is useful for these purposes.
[0007] U.S. Pat. No. 4,086,705 to Wehr discloses a dry cleaning
apparatus wherein petroleum solvent vapors which are discharged
from a dry cleaning dryer in a heated gaseous mixture of vapors and
air are condensed and recovered, and heat energy is recovered for
productive use elsewhere. The gaseous mixture of vapors and air is
sprayed with relatively cool water to condense the solvent vapors.
The resulting liquid mixture of water and solvent is withdrawn from
the spray chamber and is subjected to gravitational separation.
Water reclaimed in the separation process is reused in the spray
chamber. Recovered solvent is reused in a dry cleaning washer. The
gravitational separation process is preferably carried out in a
series of gravitational separators, and heat is withdrawn from at
least one of the separation units for productive use in a
heat-consuming device.
[0008] U.S. Pat. No. 3,807,948 to Moore teaches a method of dry
cleaning of goods in which the majority of the solvent present in
the goods at the conclusion of the actual cleaning is recovered by
circulating air, by means of a fan, through the goods in a dry
cleaning drum and through a water-cooled condenser and a heating
element. A small remaining amount of solvent is removed from the
goods by a deodorizing operation, in which air is passed in a
closed circuit through the goods in the dry cleaning drum and over
a refrigerated surface on which the solvent is condensed.
[0009] Finally, U.S. Pat. No. 3,928,660 to Alderson et al.,
discloses a dry cleaning finishing method and apparatus for use in
combination with a steam clothes press for mixing and pressurizing
a liquid so that it can be easily applied to garments being
pressed. The apparatus comprises a supply tank that meters the
liquid material into a pressure tank. Steam condensate is mixed
with steam from the clothes press and this provides the chemically
pure water, heat and pressure to the pressure tank that mixes with
the sizing concentrate and forces the water-sizing mixture to a
spray gun for use when needed or desired by the pressman.
[0010] All of the aforementioned dry cleaning methods either
require considerably more steps added to the overall dry cleaning
process thereby requiring additional time and expense in carrying
out the procedure or additional pieces of dry cleaning machinery
which takes up space and also adds to the expense of the
operation.
[0011] It is an object of the present invention to provide a dry
cleaning means and method for its operation for removing excess
cleaning solvent from the fabrics cleaned during the dry cleaning
process thereby rendering it more environmentally friendly. The
removed solvent is recaptured and contained rather than emitted
into the atmosphere.
SUMMARY OF THE INVENTION
[0012] The dry cleaning method and apparatus of the present
invention removes excess perchlorethylene (PERC) and other volatile
cleaning solvents from clothing and fabric by injecting a
predetermined amount of steam into a dry cleaning unit or vat
wherein the solvent saturated clothing and fabric have been
treated. The hot steam further volatilizes any additional PERC
remaining in or on the fabric and this is removed from the
container by vacuum. The PERC/steam mixture is then condensed and
the two components separated for re-use.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is an over-all schematic side view of a standard dry
cleaning dryer with the attached PERC steam stripper of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0014] During the course of the dry cleaning cycle in any standard
dry cleaning system, the volatile cleaning solvents such as
perchloroethylene (PERC) will often become absorbed into certain
fabrics or clothing articles in excess amounts. Dense fabrics such
as camel hair or wool often pose a problem in this regard. In many
of the dry cleaning processes known in the art, the PERC cleaning
solvent is not always fully removed and thus can result in an
unpleasant odor or feel when the article of clothing is worn.
[0015] The present apparatus and method insures that all of the
cleaning solvent used in the dry cleaning process is removed from
all the articles of clothing without damaging even the most
sensitive of fabrics. This is achieved by injecting a
pre-determined amount of steam into the drying vat or unit for a
precisely defined period of time based upon the size of the load
and the types of fabric being cleaned. The steam insures that any
excess PERC remaining in the fabric being cleaned is removed by
volatilizing the solvent molecules and then physically separating
them from the fabric altogether. This not only results in a dry
cleaned fabric material that is free from any undesirable chemical
odor and slippery feel, but the perchloroethylene or other cleaning
solvent can be separated, collected and condensed for re-use.
[0016] Referring now to FIG. 1, a conventional dry-cleaning dryer
(2) or vat is utilized to tumble dry the clothing articles and
fabrics (not shown) that have been pre-treated with and are
saturated with the cleaning solvent of choice, generally
perchloroethylene (PERC). The volatile cleaning solvents for the
most part are driven off the fabric through the application of heat
at the pre-determined range and duration according to the types of
fabric being cleaned.
[0017] In the present invention as disclosed in FIG. 1, a steam
source for the dryer is provided by the means of a steam pipe (4)
located proximate to the dryer and is in communication therewith by
means of a secondary conduct or pipe (6). A plurality of secondary
conduits (not shown) could also feed off the same steam pipe (4)
enabling several dry cleaning dryers to be utilized in tandem all
at once. The steam itself is produced by a boiler either located on
the premises or distally thereto and is fed via piping to the
primary steam pipe (4).
[0018] As discussed earlier, the amount of steam injected in the
dryer and the amount of time during which this occurs depends on
the size of the dry cleaning load and the types of fabric being
cleaned. The temperature of the steam injected is generally
governed by these factors and the type of solvent used. Obviously,
the smaller or lighter the load and/or the more delicate the
fabric, the shorter the duration of steam injection and stripping
and/or the cooler the temperature.
[0019] The duration of steam injection then is controlled by the
use of a timer (8) located externally to the dry cleaning dryer or
vat (2). Preferably, the timer is in juxtaposition to or attached
to the outer casing or wall of the dryer (2) and can be manually
set or adjusted therefrom. The timer (8) is in electrical
communication (10) with the solenoid valve (12) which it
operationally controls. Hence, when the timer is turned on to a
specified duration of time, the solenoid valve (12) is turned to
its open position and the hot steam from the steam pipe (4) is
released and enters into tumble dryer (2). The steam enters into
the dryer chamber (2) and over time fills the space not taken up by
the fabric or clothes. As the clothes tumble about within the dryer
(2), the hot steam thoroughly contacts the surface of the clothes
and volatilizes or evaporates and cleaning solvent residue
remaining thereon. Once the predetermined duration of solvent
stripping has concluded, the timer (8) turns off thereby shutting
the solenoid valve (12) and cutting off the flow of steam into the
tumble dryer or vat (2).
[0020] The dryer (2) is also provided with a conventional exhaust
fan or vacuum (not shown) which collectively draws the steam and
volatilized cleaning solvent out of internal chamber of the dryer
(2) wherein it is subsequently cooled, condensed and collected. The
two liquids can then be either physically separated or separated by
distillation means as is known in the art. In this manner, the
perchloroethylene (PERC) or other organic cleaning solvent as well
as the water if necessary can be re-used thereby adding a cost
saving benefit to the process. This is also ecologically sound in
that the solvent is self contained and not hazardously discharged
into the external environment.
[0021] Referring again to FIG. 1, the solvent steam stripper
apparatus of the present invention can alternatively be comprised
of a manual shut off valve (14) for the shut off and/or open
control of the steam release into the internal chamber of the dry
cleaning dryer (2). This manual control valve can either be
substituted for or utilized in conjunction with the electronically
controlled solenoid valve (12) and timer (8) combination. If the
manual shut off valve is used in the system by itself, it should
only be used when the fabrics to be cleaned and steamed stripped
are not delicate materials thereby requiring the use of precise
steam injection periods and wherein these times can be operatively
determined by the dry cleaner personnel themselves. When used on
the secondary injection pipe (6) together or in tandem with the
electronically controlled solenoid valve (12) and timer (8), the
manual valve (14) can be utilized as an emergency shut off means or
when appropriate, in lieu of the solenoid valve (12) and timer.
[0022] As discussed earlier, the temperature of the steam injected
into the dryer or vat (2) and the duration of time during which the
steam contacts the clothes and strips the fabric of excess cleaning
solvent is generally dependent upon the type of fabric being
cleaned and, to a lesser degree, the type of solvent used. The more
delicate the fabric, shorter steam stripping times and cooler steam
temperatures provide the best cleaning results. Consequently, the
more durable fabrics can generally withstand higher steam
temperatures and longer steam stripping application times. And
generally speaking, the duration of time during which the steam is
allowed to contact the clothes is inversely related to the
temperature of the steam. The hotter the steam, the shorter the
steam/clothing contact period and vice versa.
* * * * *