LAUNDERING METHOD SYSTEM

This invention relates to systems and methods for laundering, in particular with regard to industrial laundering using solution mixtures from electrochemical processes.

BACKGROUND OF THE INVENTION

Current laundering processes use a large amount of energy, are fairly slow, and use detergents, bleaching agents and softeners which are not environmentally desirable. Known fabric washing methods depend upon many inefficient technologies which could be improved, such as by reducing the electrical or fuel energy consumption. Additionally, a large amount of water is required for current washing processes, as approximately 10 to 30 liters of water used for the entire cleaning process of 1 kg. of soiled fabrics. Furthermore, the cycle time of a domestic/commercial washing machine process is 60 to 90 minutes to complete, and worst of all, the soiled fabrics are not thoroughly cleaned by the process.

Currently, the washed fabrics contain approximately 2% of the initial detergent, which remains entrained within the fabric, as well as 2 to 5% of the original dirt remains in the washed fabric. The detergents, softeners, bleaches and other chemicals used in the washing process are typically released into the environment. Additionally, byproducts of these chemicals may also be released into the environment.

Some prior art solutions toward improving the apparatus and method of washing fabric have used ozone which is a gas at room temperature by adding ozone to water resulting in an oxidizing agent allowing the washing of fabrics in water without detergent, however, maintaining the stability over time of the ozone content in the water has proven difficult, which has led to increased use of utilizing electrolytic ally produced oxidants in the wash water.

One such apparatus is disclosed in United States Patent No. 4,319,973 to Porta Augusta. This invention relates to a method for washing and bleaching textiles. The method according to the invention, which is carried out by means of an aqueous wash bath containing a detergent substantially free from bleaching agent, is characterized in that said bleaching is performed by incorporating into said wash

bath, at the required moment, an aqueous alkaline oxidizing solution containing in particular hydrogen peroxide ions, said aqueous alkaline oxidizing solution being produced electrolytic, immediately before its incorporation into said wash bath, by reducing oxygen at a cathode in an alkaline medium. A similar invention is disclosed in Certificate of Authorship No. SU 1687684 to A. Pulavsky et al.. This invention relates to technology and method of machine washing. The method according to the invention, which is carried out by passing through washing reservoir of washing solution, which has been electrolytically treated in a cathode chamber of diaphragm electrolyzer, prior to washing. The washing solution is treated to pH level of from 10.0 to 11.5 and Oxidation

Redaction Potential of from -600 to -800 mV. Oxygen is injected into the washing solution before washing completion.

Further prior art solutions toward improving the apparatus and method of washing fabrics have focused on developing an apparatus that can produce treated water with an elevated oxidation reduction potential of the treated water and elevated amount of hypochlorite, wherein detergent is not required in the treated water for the washing of fabrics, thereby eliminating the previously identified drawbacks related to using detergent in wash water for fabrics.

One such apparatus is disclosed in United States Patent No. 6,841 ,058 to Brian G. Culvey et al., which describes a redox bipolar cell in a fabric washing machine utilizing tap water with a low oxidation reduction potential and produces charged wash water by an electrochemical reaction to elevate the oxidation reduction potential of the wash water to remove contaminants from soiled fabrics forming charged waste water, without the use of a detergent. Another invention is disclosed in United States Patent No.5,928,490, to

Charles T. Sweeney, which discloses an improved laundry treatment system comprising a washer which is connected to discharge used water to a tank for filtration and recirculation to the washer, and a tank containing water for making up losses in the wash cycle, and an electrolytic cell therein comprising an enclosed compartment.

The electrolytic cell comprises an enclosed compartment containing an anode and a cathode supported on the outside and inside respectively of an opening in the wall of the compartment open to the surrounding liquid when the

compartment is immersed in the water in said tank for producing mixed oxidants dissolved in the make up water for oxidizing deleterious components without damaging the fabric being washed.

United State Patent Application No. 2004/0172985, to Mamiya Haruo et al., discloses an electric washing machine which performs a washing process with the use of electrolyzed water. When the level of supplied water reaches an electrolyzing water level which is lower than a washing water level, energizing of an electrolyzing device is activated. At this time, air is supplied into an electrolyzing chamber by an air pump, so that water in the electrolyzing chamber is caused to flow, thereby assisting efficient electrolysis of the water. The water thus electrolyzed has an enhanced cleaning capability thereby to improve the washing performance of the washing machine.

Some further prior art in the field includes Israel patent application No.141196, entitled "Method and Apparatus for Substrate Sterilization" filed on January 31 , 2001 to Gurevich, and Israel patent application No.170410, entitled "Method and Apparatus for Substrate and/or Soil Sterilization" filed on August 22, 2005 to Gurevich.

The idea of laundering only by mixing oxidants, without any detergents is disclosed in the patents hereinabove. However, the methods therein are limited in practice. From theoretical point of view, utilization of mixed oxidants or utilization of hypochlorous compound, such as sodium hydroxide (NaOH) or hypochlorous acid (HOCI), provides only for bleaching and disinfecting, but not for laundering/washing because these compounds are effective only in neutral, weakly acid and weakly alkaline solutions (and not in strongly alkaline solutions required for washing). The equilibrium equation of such solutions may be written:

NaOCI + H ₂ O <→ NaOH + HOCI → Na ⁺ + OH ^" + H ⁺ + OCI ^" (1 )

As is well known, the laundering process is performed in three sequential steps: a) washing step in an alkaline medium ( pH = 10.0 - 12.0, ORP = -700 - 900 mV); b) bleaching and disinfection step in an acid medium (pH = 2.0 - 4.0, ORP = 800 - 1 ,20O mV); and

c) rinsing, neutralization and softening step in a neutral medium (pH = 6 -

8, ORP = 400...- 20O mV).

Step a) can only proceed efficiently in a highly alkaline medium/solution with above mentioned parameters of pH and ORP, such that the following saponification reaction occurs:

R1-COO-R2 (Fatty acid) + NaOH (Sodium hydroxide) <→ RI-COO-Na (Soap) + R2-OH (Glycerol) (2)

This reaction allows the soap to soften the water, decompose fatty acids, neutralize amino acids and proteins and remove decomposed substances from linen.

Step b) in an acid medium with above mentioned parameters of pH and ORP, a chloramination reaction occurs, in accordance with following equation: R-CHNH ₂ COO-OH (Amino acid) + HOCI (Hypochlorous acid) <→ R-CCINH ₂ COO-OH (Chloramine) + H2O (Water) (3) This reaction allows bleaching and disinfection to occur, with decomposition of amino acids, proteins, any kinds of dye-stuffs etc.

Step c) in neutral weakly acid or weakly alkaline medium with above mentioned parameters of pH and ORP, a neutralization reaction in accordance with next equation may occur: R-CHNH ₂ COO-OH (Amino acid) + NaOH (Sodium hydroxide) «→

R-CHNH ₂ COO-ONa (Salt) + H ₂ O (Water) (4) or

R-CHNH ₂ COO-OH (Amino acid) + NaOCI (Sodium hypochlorite) <→ R-CHNH ₂ COO-ONa (Salt) + HOCI (Acid) (5) It should be understood that one cannot achieve a saponification reaction in a weakly acid or weakly alkaline medium (solution), such as using mixed oxidants without detergent, per the prior art patents. These prior art processes allow for a good bleaching effect, but reactions products, such as salts, decomposed proteins, fats and other residual soil may still remain in the fabrics. This has been confirmed by laboratory analyses.

United States Patent No. 6,132,572, to Kim, describes an electrolyzer apparatus including anode and cathode units that are alternately arranged in a sandwich type fashion separated from each other by ion exchange membranes.

Two inlet streams of water introduced into the apparatus wherein one water stream is routed through the anode sections and the other water stream is routed through the cathode sections, and resulting in two treated water outlet streams, with the anode stream being highly acidic and the cathode stream being highly alkaline that cumulates in an elevated oxidation reduction electric potential ranging from-900 to +1180 mV. This device has several drawbacks, namely: air plugging in the chamber until it does not function properly, and b) the washing effect (washing quality) is estimated on a basis of reflection factors from dirty and clean fabrics and do not take in consideration the amount of residual dirt in the fabric. Another device is disclosed in United States Patent Application

No.2002/023847 to Natsume Shinichi. This invention provides a cleansing and sterilizing apparatus for cleaning embodiments such as dishes, medical devices, clothing, etc. The apparatus comprises an electrolysis chamber that uses an ion exchange membrane to separate a cathode section from an anode section of the chamber. Tap water is injected into cathode section and saltwater is injected into the anode section. Electrolysis in the anode section of the electrolysis chamber forms acidic water and HOCI, which has antibacterial and disinfectant properties. In addition, electrolysis in the cathode section of the electrolysis chamber forms alkaline water and sodium hydroxide (NaOH), which has cleansing and reducing properties.

The alkaline water and sodium hydroxide is then pumped out of the electrolysis chamber sprayed on embodiments to be cleansed, such as medical devices (endoscopes, dialysis equipment), dishes, etc. After cleansing, the embodiments may then be optionally sprayed with the acidic water and HOCI to sterilize or disinfect the embodiments. In alternative embodiments of the apparatus, the ion exchange membrane includes an anion exchange membrane, a cation exchange membrane, and a neutral membrane. In another embodiment of the invention, the electrolysis chamber does not include an ion exchange membrane, thereby reducing costs of manufacturing and using the invention. United States Patent No. 6, 841 ,058 to Brian G. Culvey et al., discloses a redox bipolar cell fabric washing system and method that provides for washing fabrics without the use of any added detergents, fabric softeners, or bleaches, or other chemical al additives. The system includes a conventional fabric washing

machine with a redox bipolar cell that through a circulation pump continuously treats the wash water by using mixed oxidants or charged wash water to remove contaminants from the fabric. The redox cell includes housing, a plurality of cathode plates, a plurality of membranes, and a plurality of anodes proximately positioned in an alternate manner with a plurality of flow channels in the housing. The cell produces charged wash water by an electrochemical reaction utilizing electrically charged anodes and cathodes with semi permeable membranes, wherein the oxidation reduction potential of the charged wash water is continuously controlled with a sensor to determine when the fabrics are clean. This invention has many drawbacks such as not being able to provide fully cleaned laundry because use of oxidizing mixture for laundering is not effective. This necessitates the use of many additives, such as enzymes, optical brightener, softener, deodorant etc. Furthermore, the redox potential sensor described cannot measure the laundering solution in real-time inside the tub where fabric or clothes are being laundered.

There is thus still a need to provide an energy-efficient and cheap, environmentally friendly and user-friendly quick washing process and method.

SUMMARY OF THE INVENTION

Some embodiments of the present invention are directed to systems and methods for laundering fabrics in processes wherein the pH and ORP levels are kept substantially constant over a long period of time. More particularly, in all of the three steps: a) washing/laundering, b) disinfecting and bleaching and c) rinsing, the solution compositions are retained within strict parameter regimes by means of adding tap water, catholyte or anolyte and additives, responsive to a detected change in the solution composition in the washing machine.

Some further embodiments of the present invention provide for real-time in situ monitoring of pH and/or ORP in said steps a)-c).

A further embodiment of present invention describes pH and/or ORP control of the catholyte and anolyte, so as to provide an optimized process for providing high quality washing, disinfecting and bleaching and rinsing steps.

Yet a further embodiment of present invention is directed to a mixture formulation comprising salts, such as NaCI and KNO ₃ to produce many kinds of chlorides, chlorides-oxides and oxides for destroying bright range of colored stains in clothes.

Yet a further embodiment of present invention provides a reduced cycle time wash and dry process by rinsing clothes in washing machines with a catholyte, allowing a significant decrease in drying time of washed clothes in a drying machine.

The catholyte, can, according to some embodiments, be used in both the washing and rinsing steps (a) and (c) respectively.

Yet a further embodiment of present invention provides optimized use of additive solutions such as enzymes, grease removers, optical brighteners, softeners etc., in said washing and disinfecting and bleaching solutions steps.

Another embodiment of present invention provides optimized use of additive solutions to water in membrane-less and membrane apparatus for electrolysis.

An additional embodiment of present invention describes a computer- controlled system for laundering, comprising at least one electrolysis apparatus and a pH controlled washing drum.

Additionally, according to some embodiments, the system may comprise any one or more of an SBW-tunnel washer, a PLC - Programmable Logical Controller, a

set of electric valves, pumps, pH sensors and flow meters. In some embodiments, the system comprises all of the above.

Furthermore, the system may comprise an additional hydraulic system for additives feeding and activation in a membrane electrolysis apparatus, a salt mixing preparation unit; tanks for catholyte, anolyte, enzyme, grease remover, optical brightener, softener and odorant

Yet a further embodiment of present invention provides a system for laundering including a reverse osmosis module, sometimes mounted at the entry of the system. There is thus provided, according to some preferred embodiments of the present invention, a computer-controlled laundering method comprising; i) providing at least one catholyte and at least one anolyte from at least one electrolysis apparatus to a washing apparatus; and ii) laundering an item in; a) a washing step in at least a first solution comprising the at least one catholyte under maintained pH and oxidative-reduction potential (ORP); b) a bleaching/disinfecting step in a second solution comprising the at least one anolyte under maintained pH and oxidative-reduction potential (ORP); and c) a rinsing step in a rinsing solution; in said washing apparatus to provide a substantially clean item, wherein at least one of the pH and ORP of at least one of said catholyte introduced into said washing step and said anolyte introduced into said bleaching/disinfecting step are substantially continuously monitored and at least one of the pH and

ORP of at least the fluid in said washing step is periodically monitored to achieve said maintained conditions, at least in part by controlling at least the amount of catholyte introduced into said washing step. The term "periodically" as used herein is intended to denote a monitoring which is affected periodically, one to ten times per day.

According to some embodiments, the at least one catholyte and at least one anolyte are produced in a multi-stage electrolysis apparatus. In some cases, the

multi-stage electrolysis apparatus comprises a membrane-less electrolysis apparatus and a membrane electrolysis apparatus.

WO 2006/070352 to Ramati et al., teaches a method for laundering textiles comprising washing the textiles using a cation solution (anolyte) and bleaching and disinfecting the textiles using an anion (catholyte) solution. The present invention teaches away from '352 in that the opposite laundering methodology is performed, i.e., the washing step is performed in the catholyte solution and the bleaching/disinfecting step in the anolyte solution.

More significantly, the present invention teaches in-situ (inside the washing tub or tunnel) continuous pH monitoring with feed-back control of additives to maintain the process parameters, which is neither hinted to nor suggested in '352.

Additionally, the present invention teaches the use of a multistage electrolysis apparatus, including a membrane electrolysis module, which was not described or hinted to in '352. This multistage apparatus provides for more efficient washing and bleaching steps due to the improved anolyte and catholyte properties, relative to the single stage electrolysis module of the prior art.

The method of the present invention, according to some embodiments, provides the anolyte at a pH value of from 1.3 to 3 and an ORP to Platinum, relative to Ag/AgCI, of from +500 to +1250 mV and the catholyte is provided at a pH in the range of from 11.3 to 12.5 and a range of ORP to Platinum, relative to Ag/AgCI, of from -800 to -95OmV.

In some cases, the laundering method is performed in a washing apparatus selected from a drum washing apparatus and a tunnel washing apparatus. The tunnel washing apparatus may comprise a washing zone, a bleaching - disinfecting zone and a rinsing zone. Thus, the washing step may be performed in the washing zone of the tunnel washing apparatus.

According to some embodiments, the pH of the first solution is maintained from catholyte from catholyte tank within a range of 11 to 12.4.

Typically the ORP of the first solution is maintained within a range of ORP to Platinum, relative to Ag/AgCI, of from -650 to -92OmV.

According to some embodiments, the bleaching/disinfecting step is performed in the bleaching - disinfecting zone of tunnel washing apparatus. The pH

of the second solution may be maintained from anolyte from anolyte tank within a range of 1.7 to 2.4.

In some cases, the ORP of the second solution may be maintained within a range of ORP to Platinum, relative to Ag/AgCI, of from +800 to +1200 mV. In some embodiments, the rinsing step is performed in the rinsing zone of the tunnel washing apparatus. The pH of the rinsing solution may be maintained within a range of 6.0 to 8.0, and the ORP of the rinsing solution may be maintained within a range of ORP to Platinum, relative to Ag/AgCI, of from -300 to + 300 mV. According to some embodiments, the catholyte and anolyte are produced by electrolysis of an aqueous solution comprising NaCI at a concentration of from 0.5 to2.5 g/l and KNO ₃ at a concentration of from 0.5 to 2.5 g/l.

In some cases, the first solution further comprises at least one washing additive selected from; an enzyme, a grease remover and an optical brightener. Preferably, the at least one washing additive improves at least one of a washing rate and a washing quality of the washing step.

According to some embodiments, the rinsing step is carried out in a rinsing solution comprising the catholyte and tap water. The rinsing solution may further comprise at least one rinse additive selected from a fabric softener and an odorant. Preferably, the at least one rinse additive improves at least one of a rinsing rate and a rinsing quality of the rinsing step.

In some cases the method further comprises a drying step. Advantageously, the drying step time of the present invention may be reduced by up to 50% relative to a standard laundering process. Furthermore, according to the method of the present invention, the washing additives may be used in quantities of 20% to 50% relative to a standard laundering process.

Further advantages of the method of the present invention, include the saving in rinse additives, which may be used in quantities of 20% to 50% relative to a standard laundering process.

According to some embodiments of the method of the present invention, the additives electrolytic pretreatment allows for up to a ten-fold saving in the use of additives relative to a standard laundering process.

Another notable advantage of the method of the present invention is that the substantially clean item comprises less than 1.0 percent of the original contaminant, the contaminant being selected from dirt, microorganisms, odor and stains.

There is further provided, according to some embodiments of the present invention, a method for laundering of an item comprising; a) a first step of laundering comprising washing in a washing solution of pH from 10.8 to 12.3 and ORP to Platinum, relative to Ag/AgCI, of from - 600 to -900 mV, the washing solution comprising a catholyte in combination with tap water and additives, wherein the pH of the catholyte is from 11.0 to 12.4 and the ORP of the catholyte to

Platinum, relative to Ag/AgCI, is from -650 to -920 mV; b) a second step of laundering comprising bleaching and disinfecting in a bleaching and disinfection solution, having a pH of from 1.9 to 2.8 and ORP to Platinum, relative to Ag/AgCI, of from +750 to +1160 mV, wherein the bleaching and disinfection solution comprises the anolyte in combination with tap water, wherein the pH of the anolyte ranges from 1.7 to 2.4 and/or ORP to Platinum, relative to Ag/AgCI, of from +800 to +120O mV and c) a third step of laundering comprising rinsing in a rinsing solution, wherein the rinsing solution comprises tap water, catholyte and additives; wherein the pH and ORP in the washing step and in the bleaching/disinfecting step are substantially continuously monitored to achieve the maintained conditions by controlling the amount of catholyte and anolyte respectively introduced into each of the steps.

Additionally, according to some embodiments of the present invention, there is provided a computer-controlled laundering system comprising; i) at least one electrolysis apparatus; and ii) a washing apparatus comprising at least one washing chamber with in situ controllers for maintaining the pH and oxidative-reduction potential

(ORP) of at least one solution contained therein.

In some cases, the at least one electrolysis apparatus may comprise a membrane-less electrolysis apparatus and a membrane electrolysis apparatus.

Preferably, the at least one electrolysis apparatus is configured to produce an anolyte having a pH value of from 1.3 to 3 and an ORP to Platinum, relative to

Ag/AgCI, of from +500 to +1250 mV and a catholyte having a pH in the range of from 11.3 to 12.5and an ORP to Platinum, relative to Ag/AgCI, of from -800 to - 95OmV.

In some cases, the washing apparatus is selected from a drum washing apparatus and a tunnel washing apparatus. The tunnel washing apparatus may comprise a washing zone, a bleaching - disinfecting zone and a rinsing zone. Normally, the washing zone is configured and operative to maintain a washing solution at a first pH and first ORP, the bleaching - disinfecting zone is configured and operative to maintain a disinfecting and bleaching solution at a second pH and second ORP, and the rinsing zone is configured and operative to maintain a rinse solution at a third pH and third ORP.

According to some embodiments, the computer-controlled laundering system may further comprise a reverse osmosis apparatus, configured to supply purified water to the at least one electrolysis apparatus.

In some cases, the membrane electrolytic module comprises an ion exchange membrane. The ion exchange membrane is typically disposed between at least one cell for collecting anolyte and at least one other detached cell for collecting catholyte.

Preferably, the at least one anolyte cell is configured to provide anolyte of a pH value of from 1.3 to 3 and an ORP to platinum, relative to Ag/AgCI, of from +500 to +1250 mV. Additionally, the at least one catholyte cell is configured to provide catholyte of a pH value of from 11.3 to 12.5 and an ORP to platinum, relative to Ag/AgCI , of from -800 to -95OmV.

The computer-controlled laundering system may be constructed with the at least one anolyte cell including an anode housing with an inlet and an outlet nozzle, wherein ratio in cross section between the inlet and outlet nozzle is around 1 :2.

Additionally, the computer-controlled laundering system may include the at least one catholyte cell comprising a cathode housing with an inlet and an outlet nozzle, wherein ratio in cross section between the inlet and outlet nozzle is around 1:2.

The computer-controlled laundering system, including the membrane electrolysis apparatus, may comprise an anode with an MMO coating from RuO ₂ and Irθ ₂ in a ratio of 1 : 1.

The computer-controlled laundering system of the present invention includes a system, substantially as shown in the figures.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to understand the invention and to see how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: Fig. 1 is a simplified diagram of an industrial drum washing system in accordance with some embodiments of the present invention;

Fig. 2 is a simplified diagram of an industrial tunnel washing system in accordance with some embodiments of the present invention;

Fig. 3 is a simplified flowchart of a method for laundering, in accordance with some embodiments of the present invention; and

Fig. 4 is a simplified flowchart showing sub-steps of step 310 of Fig. 3.

Identical reference numerals refer to similar or identical parts in different figures.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Some embodiments of the present invention are directed to systems and methods for laundering fabrics in processes wherein the pH and ORP levels are kept substantially constant over a long period of time. More particularly, in all of the three steps: a) washing/laundering, b) disinfecting and bleaching and c) rinsing, the solution compositions are retained within strict parameter regimes by means of adding tap water, catholyte or anolyte and additives, responsive to a detected change in the solution composition in the washing machine.

Fig.1 is a simplified diagram of an industrial washing system 100 having a drum washing machine or washer 23 in accordance with some embodiments of the present invention.

Fig. 2 is a simplified diagram of an industrial tunnel washing system 200 comprising a tunnel washer 22, in accordance with some embodiments of the present invention

The present invention achieves pH and ORP stability within a drum washing machine 23 (Fig. 1) and/or within a tunnel washing machine 22 (Fig. 2) by providing constant monitoring of washing, bleaching and disinfection solutions parameters and immediately correcting any of the parameters upon deviation thereof from an upper and a lower limit.

The set up and control of the drum washer 23 (Fig. 1) and tunnel washer 22

(Fig. 3) are very similar. Identical reference numerals refer to similar or identical parts in different figures and the following description refers to both Fig. 1 and Fig. 2.

Tap water is fed to inlet electric cock 1 and divided into two streams: a) one to the washing machines - drum washer 23 and to tunnel washer -CBW 22 and the other b) to salt tank 41 and membrane-less electrolysis apparatus 2 and through regulating valve 8, flow-meter 9 to inlet nozzle 10 of an anolyte chamber of membrane electrolysis apparatus 12.

Water is then fed regulating valve 38 and flow-meter 39 to inlet nozzle 10 of catholyte chamber.

A salt tank 41 is filled with water through check valve 49 and salt (from time to time) for saline water formation, which is further fed tap water from feed pipe by metering pump 42, where tap water and saline water are mixed with water and the resultant solution is fed to inlet nozzle 5 of membrane-less electrolysis apparatus 2. Membrane-less electrolysis apparatus 2 comprises a housing, an anode 3 and a cathode 4, an inlet nozzle 5 and an outlet nozzle 6. The anode is constructed from a

Titanium substrate with an MMO coating from RuO ₂ and IrO ₂ in an equal ratio (1 :1) while the cathode is instructed from any suitable material such as uncoated titanium.

The housing and electrodes can be round or flat, but, in any case, a distance between anode and cathode is generally from 4 to 20 mm.

A conductivity meter sensor 50 is set at the end of an inlet nozzle 5 to the membrane-less apparatus 2. The sensor regulates the quantity of saline water entering apparatus 2. The aqueous solution in the processing chamber of membrane-less apparatus 2 is subject to an electric current from anode 3 and cathode 4, which are both connected to a DC supplier 7, and the current passes through the processing chamber such that electrochemical reactions occur at the anode and cathode. Ions generated at the anode are cations and chemical agents, such as, but not limited to HOCI, HCI, Cl ₂ , H ⁺ , HO ₂ , H ₃ O+, Na ⁺ , and K ⁺ . At the

cathode, the following types of anions are generated OH ^" , H ₃ O ₂ ^" , NO ₃ ^" , CO ₃ ^2" , SO ₄ ^2" , CIO ^" . These cations and anions may react together in one or more neutralization reactions resulting in non-treated aqueous solution and reactions products such as NaOCI, NaOH, KOH, H ₂ O, HOCI etc. with pH about of from 8.0 to 9.0 at outlet nozzle 6 of membrane-less apparatus exit.

After passing through the membrane-less apparatus 2, the resultant aqueous solution and reactions products are fed into membrane apparatus 12 as described above. Membrane electrolysis apparatus 12 comprises a housing, an anode 13, a cathode 14, a membrane 54, inlet nozzles 10 for anode and cathode chambers and outlet nozzles 11 for anode and cathode chambers, The anode is constructed from a Titanium substrate with an MMO coating of RuO ₂ and IrO ₂ in an equal ratio (1 :1). The cross section ratio of the outlet nozzles 11 to cross-section of the inlet nozzles 10 is, in some cases, 2:1.

Electrochemical reactions occur at the anode and at the cathode. However, apparatus 12 has a membrane disposed between the anode and cathode chambers. Thus, the neutralization reactions occurring in apparatus 2, cannot occur herein due to their separation by the membrane. Thus, electrochemical reaction products accumulate in their respective chambers and exit the chambers through outlet nozzles 11 of membrane apparatus 12 to catholyte tank 15 and anolyte tank 16.

As described above the pH level of the catholyte in tank 15 is typically in the range of 11.0 to 12.4 and ORP to Platinum, relative to Ag/AgCI, in the range of from -650 to -920 mV. The pH level of the anolyte in tank 16 is typically in the range of from 1.7 to 2.4, and ORP to Platinum, relative to Ag/AgCI, of from +800 to +1200 mV.

The anolyte and catholyte produced are for use in the laundering process in drum washer 23. Additives may also be added to the drum washer to improve the laundering quality, thus an enzyme holding tank 17 contains a solution of washing enzymes known in the art, such as lipases. Another additive used in the art is a grease remover (any kind of solvent) held in tank 18. An optical brightener is held in tank 19. A softener is held in a softener- tank 20. One or more fragrances or odorants are held in tank 21. All the aforementioned tanks are connected to drum washer 23 (in Fig. 1) or to tunnel washer - CBW 22 (Fig. 2). All solutions are fed to

the respective washers either by gravitation, per tank 15 for catholyte and tank 16 for anolyte, or by metering pumps 28 and electric valves 51, 52 and 63 for the greaser remover, metering pump 29 and electric valves 59, 53 and 64, for the enzyme, metering pump 30 and electric valves 55, 56 and 62 for the optical brightener, metering pump 31 and electric valves 57 and 58 for the softener, and atomizer 61 for the odorant.

Referring further to Fig. 1, by laundering with drum washer 23 in washing phase, the catholyte from tank 15 is used with additives such as grease remover from tank 18, enzyme from tank 17, optical brightener from tank 19 and tap water by means of electrical valve 45. The required pH level of the washing solution in this phase is controlled by time control of electrical valves 34, 45, 51, 55 and 59, which is based on a response to the readings from pH sensors 43.

In a bleaching and disinfecting phase, anolyte is added from tank 16, supplied using time control of electrical valve 33 and tap water added by means of electrical valve 44, which is based on a response to the readings from pH sensors

43.

The required pH level of the rinsing solution is supplied in this phase by time control of electrical valves 34, 44 and 58, which is established on basis of pH measurements from pH sensors 43. It should be emphasized that in prior art washing systems the pH level in a drum washer was not monitored since the pH sensor was disposed externally to the drum washer.

Turning now to Fig. 2, it should be noted that in laundering with a CBW - tunnel washer 22, there are three different laundering zones: 1) a washing/laundering zone with a highly alkaline pH level;

2) a bleaching- disinfecting zone with a low and acidic pH level; and

3) a rinsing zone with neutral or alkaline pH level.

The three zones are continuously controlled by three respective pH sensors 24, 25 and 26. In the washing zone, the washing solution used is the catholyte from tank 15, with the addition of additives such as grease remover from tank 18, enzyme from tank 17 and optical brightener from tank 19. Tap water is added by means of electrical valve 46. The required pH level of the washing solution to this zone is

effected by time control of electrical valves 35, 52, 53 and 56, which is established by measurements from pH sensor 24.

In the bleaching and disinfecting zone, anolyte is used as a bleaching and disinfecting solution, and is received from tank 16. Tap water is added to this zone by means of electrical valve 47.

The required pH level of the bleaching and disinfecting solution is supplied by time control of electrical valves 36 and 47, which is established on the basis of pH measurements from pH sensor 25.

In the rinsing zone, the required pH level of rinsing solution is supplied to this zone by activation of electrical valves 37, 48 and 57, which, in turn are fed signals on the basis of pH measurements from pH sensor 26.

All laundering operations with either the drum washer 23 or CBW - tunnel washer 22 are controlled by means of a controller, exemplified herein by, but not limited to Programmable Logic Controller (PLC) 40. Any other computer control system of the art could be used in place of PLC 40. PLC 40 has inputs (24, 25, 26, 43, 50, 9, and 39) and outputs (1, 7, 8, 9, 38, 49, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 42, 44, 45, 46, 47, 48, 51 , 52, 53, 55, 56, 57, 58, 59, 60, 61 , 62, 63 and 64).

Typically, the PLC will have several different programs for corresponding washing programs for different types and quantities of clothes. Reference is now made to Fig. 3, which is a simplified flowchart 300 of a method for laundering, in accordance with some embodiments of the present invention.

In a first step, 310 catholyte and anolyte solutions are prepared in one or more electrolytic stages. Further details of this step are described with reference to Fig. 4 hereinbelow.

In a washing or laundering step 320, soiled, dirty or stained clothes are placed in the washer, such as drum washer 23 (Fig. 1) or tunnel washer 22 (Fig.2). Tap water or reverse osmosis water is fed from via a water pipeline and valves 1 , 34 from 60 to the washer, 22 or 23. Catholyte from tank 15 is fed and mixed with the water such that the resultant solution is a washing solution of pH from 10.8 to 12.3 and ORP to Platinum, relative to Ag/AgCI, of from - 600 to -900 mV. Typically, the washing solution comprises the catholyte in combination with tap water and additives, wherein the pH of the

catholyte is from 11.0 to 12.4 and the ORP of said catholyte to Platinum, relative to Ag/AgCI, is from -650 to -920 mV.

The additives added to the washing stage are grease remover from tank 18, enzyme from tank 17, optical brightener from tank 19 and tap water by means of electrical valve 45. The required pH level of the washing solution in this phase is controlled by time control of electrical valves 34, 45, 51 , 55 and 59, which is based on a response to the readings from pH sensor 43.

Typically, the ratio of the water: catholyte is 1 : 1.

Typically the quantities of additives used are 20 - 30%, which are 70% less than the requirements of prior art processes.

The washing step is performed under controlled and maintained pH and

ORP. For example, if the pH of the washing solution drops from 11.5 to 10.8, pH sensor 43 measures the in situ pH of the washing solution in the washer and the

PLC receives signals from the pH sensor and sends a signal back to valve 34 which allows more catholyte to feed into the washer and the pH is raised.

According to some embodiments, the pH and ORP are set to a set-point and the PLC adds one or more of an additive, water, catholyte and anolyte responsive to the pH change.

Typically the washing stage takes 2 to 10 minutes and is performed at a temperature of 17 to 40 ⁰ C.

According to some embodiments, at least one of a drain and a spin step is performed in the drum washer 23 to evacuate the spent washing solution prior to the next step. The wet clothes remain in the drum washer for all steps in flowchart 300.

According to some embodiments, at least one drain step is performed in the tunnel washer 22 to evacuate the spent washing solution prior to the next step. However, the wet clothes are passed from the washing zone to the next zone (disinfect and bleach zone) prior to the starting of the next step.

In a disinfect and bleach step 330, a bleaching and disinfection solution is added to the washer, having a pH of from 1.9 to 2.8 and ORP to Platinum, relative to Ag/AgCI, of from +750 to +1160 mV. The bleaching and disinfection solution comprises the anolyte from tank 16 in combination with tap water.

Typically the pH of the anolyte ranges from 1.7 to 2.4 and/or ORP to Platinum, relative to Ag/AgCI, of from +800 to +1200 mV.

Typically the disinfecting and bleaching step takes 2 - 8 minutes and is performed at a temperature of 17 - 4O ⁰ C.

According to some embodiments, at least one of a drain and a spin step is performed in the drum washer 23 to evacuate the spent disinfect and bleach solution prior to the next step. The wet clothes remain in the drum washer for all steps in flowchart 300.

According to some embodiments, at least one drain step is performed in the tunnel washer 22 to evacuate the spent disinfect and bleach solution prior to the next step. However, the wet clothes are passed from the disinfect and bleach zone to the next zone (rinse zone) prior to the starting of the next step.

In a rinse and soften step 340, a rinsing solution is passed into the washer, wherein said rinsing solution comprises tap water from valve 1 and softener from valves 57 and 58. Commercial softeners used according to this invention. Typically the quantities of softener and other additives used are 20 - 30%, which are 70% less than the requirements of prior art processes.

The rinsing step may include several rinse, drain and spin sub-steps as are known in the art.

Typically the rinse and soften step takes 1 - 3 minutes and is performed at a temperature of 17 to 40 ⁰ C. Thus steps 310-340 take from 8 to 18 minutes in the drum washer and from

10 to 24 minutes in the tunnel washer as function of the tunnel construction.

An optional drying step may be performed after step 340, which is performed at 80 -120 ⁰ C over a time of 3 - 18 minutes. This drying step is much shorter than the drying steps of the prior art. Without being bound or limited to any theory, this may be because the surface tension of the catholyte is much less than that of tap water and thus is energetically less bound to the fabrics or clothes after the rinsing step.

Reference is now made to Fig. 4, which is a simplified flowchart 400 showing sub-steps of step 310 of Fig. 3. In a reverse osmosis step 410, tap water is fed into a reverse-osmosis module 60. The tap water typically has the following properties: pH=5.0 - 9.0, hardness= 60 - 180 ppm , conductivity = 0.1 - 1.5 mS. The reverse osmosis module provide reverse osmosis water having the following properties pH= 6.5,

hardness= 0 - 2 ppm, conductivity = 10 -15 μS. The function of the reverse osmosis step is to clean the tap water from Ca and Mg.

In a first electrolysis step 420, one or more of tap water and reverse osmosis water from step 410 are fed via valve 1 into apparatus 2. Salts added to the water from salt tank 41 such that the resultant saline solution comprises NaCI at a concentration of from 0.5 to2.5 g/l and KNO ₃ at a concentration of from 0.5 to 2.5 g/l. A current is passed between the electrodes (anode and cathode) 3, 4 such that electrochemical reactions occur. Ions generated at the anode are cations and chemical agents, such as, but not limited to HOCI, HCI, Cl ₂ , H ⁺ , HO ₂ , H ₃ O+, Na ⁺ , and K ⁺ . At the cathode, the following types of anions are generated OH ^" , H ₃ O ₂ ^" , NO ₃ ^" , CO ₃ ^2" , SO ₄ ^2" , CIO ^" . These cations and anions may react together in one or more neutralization reactions resulting in an aqueous solution, comprising reactions products such as NaOCI, NaOH, KOH, H ₂ O, HOCI etc., with a pH about of from 8.0 to 9.0 at outlet nozzle 6 of membrane-less apparatus exit. In a second electrolysis step 430, a membrane electrolysis step is performed.

The aqueous solution from nozzle 6 in step 420 is fed into apparatus 12.

A current is applied and an anolyte and catholyte solution form at anode 13 and cathode 14 respectively. As described hereinabove, the pH level of the resultant catholyte is typically in the range of 11.3 to 12.5 and ORP to Platinum, relative to Ag/AgCI, in the range of from -800 to -950 mV. The pH level of the resultant anolyte is typically in the range of from 1.3 to 3.0, and ORP to Platinum, relative to Ag/AgCI, of from +500 to +1250 mV.

It should be understood that the methods of the present invention allow for optimized washing/laundering processes in comparison to prior art processes. Some of the advantages include, but are not limited to:

? cleaner clothes- highly efficient washing cycle

? no requirement for detergent

? no environmental problems due to release of detergents

? no detergents traces in clean clothes ? energy saving-less or no requirement to heat water

? shorter washing cycles - saving in electricity and labor

? shorter energy-saving drying cycles

? smaller quantities of utilized water relative to standard processes ? smaller quantities of additives relative to standard processes ? reproducible cycles due to maintained parameter control ? washing cycle parameters matched to type and quantity of clothes. Very dirty clothes, such as hospital blood-stained laundry may require enzymes to denature blood proteins. Prior art processes for such laundry needed to be carried out at a pH of 8.6, with a working temperature to 50 ⁰ C. Furthermore, in prior art processes for bleaching such blood-soiled clothes, it was necessary to use both a chemical bleacher and an optical brightener at a pH of 9.6 and working temperature of from 60 to 90 ⁰ C. However, according to the present invention, the prior art process can be replaced by the washing/laundering step 320 with the addition of the required enzymes and optical brightener in the catholyte solution at temperature of about 30 or 35 ⁰ C (taking into account higher catalytic ability of catholyte). Mineral grease can be removed by adding any kind of solvent at a pH of 10.0 as an additive to the catholyte solution in step 320.

Fabric softening can be achieved in several different ways, according to some embodiments of the present invention: a) the catholyte may be added to water at ratio of from 1:9 to 9:1 and the resultant catholyte solution may be used as a rinsing medium; b) a softener may be added to an anolyte solution at pH of 3.5 in a quantity of 3 to 5 fold less in comparison to regular washing. c) Additives may be added in a quantity of from 7 to 10 less compared to regular washing after pretreatment in the membrane electrolysis apparatus 12

Another notable improvement of the present invention over the prior art is the combination of NaCI and KNO ₃ salts in the electrolysis process. Such combination of salts in concentration of from 0.5 to 2.5 g/l produced sufficient amount of chloric oxidants (Cl ₂ , HCI), chloric - oxygen oxidants (HOCI) and oxygen oxidants (O ₂ , H ₂ O ₂ , HO ₂ , HO ³⁺ etc.), what is necessary for stain elimination (bleaching) of any specific disinfectants, e.g. as ALCOXIDINE (Skin disinfectant).

Yet another advantage of the present invention over the prior art is the reduction in drying time of clothes washed according to the method of the present invention. This has been verified experimentally and may be due to the fact that the surface tension of the catholyte is only 36x10 ³ N/m relative to tap water 72x10 ³ N/m.

Yet another advantage of the present invention over the prior art is the use of two electrolytic stages (2, 12), thus producing the anoiyte and catholyte by consecutively passing saline water through first the membrane-less electrolysis apparatus 2 wherein there is precipitation of Ca and Mg carbonates. Thereafter the solution is passed through then anode and cathode chambers of membrane electrolysis apparatus 12, having a membrane between the anode and cathode chambers. This arrangement allows for a decrease in the quantity of carbonates precipitation on the cathode of membrane electrolysis apparatus 12, thus improving quality of Electrochemically Activated Water (EAW) and extending the operating time of apparatus 12.

Another function advantage of the two stage electrolytic cell arrangement is that the pH level of the catholyte from membrane electrolysis apparatus is significantly higher (11.3 to 12.5) than that of a one-stage process (8-9).

A structural advantage of the electrolysis apparatus of the present invention is that the use of an anode coating comprising RuO ₂ and IrO ₂ in a ratio of approximately 1 :1. The anode coating allows production of chloric oxidants, chloric - oxygen oxidants and oxygen oxidants by various reactions from NaCI and KNO ₃ , the salts used in the electrolysis process.

Another structural advantage of the electrolysis apparatus of the present invention is that membrane electrolysis apparatus 12 is constructed such that the ratio of the inlet cross-section nozzle to outlet nozzles is 1 :2, and this, in turn, provides protection to the inlet piping from hydraulic shock, due to gases generated from the electrolytic reactions. This arrangement also provides a freer exit of the catholyte and the anoiyte to their respective storage tank 15, 16. DEFINITIONS

As used herein, the following terms are defined as follows:

Electrochemical Activation (ECA) - it is electrolysis of all kinds of liquids with small amount of salts for producing electrochemically activated (energetically exited)

liquids such as anolyte and catholyte by applying a voltage of from 5V to 100,000V in accordance with liquids characteristics.

Electrochemically Activated Water (EAW) - electrochemically activated (energetically exited) liquids such as anolyte and catholyte Anolyte - a cation containing liquid after treatment in ECAC;

Catholyte - an anion containing liquid after treatment in ECAC

Electrochemical Activator (ECAC) - a certain type of electrolyzer for the production of anolyte and catholyte:

Anode chamber - a half-cell of the activator wherein anolyte is produced; Cathode chamber - a half-cell of the activator wherein catholyte is produced;

ORP - Oxidation-Redaction Potential.

PLC - Programmable Logic Controller.

EC - Electro-Conductivity of a liquid.

RO - Reverse Osmosis The references cited herein teach many principles that are applicable to the present invention. Therefore the full contents of these publications are incorporated by reference herein where appropriate for teachings of additional or alternative details, features and/or technical background.

It is to be understood that the invention is not limited in its application to the details set forth in the description contained herein or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Those skilled in the art will readily appreciate that various modifications, such as pH, temperature and ORP and changes can be applied to the embodiments of the invention as hereinbefore described without departing from its scope, defined in and by the appended claims.

It will also be understood that the invention further contemplates a machine- readable memory tangibly embodying a program of instructions executable by the machine for executing the method of the invention.