FR3135735A1 - installation and process for dry cleaning composite textile articles. - Google Patents

Abstract

The present invention relates to a dry degreasing process, in particular for composite textile articles, in particular work gloves, partially covered with mineral grease. According to the process, said articles are impregnated with a first solvent comprising/consisting of a mixture of alkanes free of halogen and then an additive comprising or consisting of a mixture of aliphatic hydrocarbons free of halogen is optionally sprayed onto said soaked articles. halogen and/or at least one non-ionic and/or cationic surfactant, a mechanical action is exerted on said articles, said articles are then wrung, the liquid mixture resulting from the spinning is distilled so as to separate at least said first solvent, the water used for the condensation of the distilled solvent is cooled and it is reused for the condensation of the solvent after the distillation and/or the water used for the distillation is used and which is therefore at a higher temperature at room temperature to wash other textile items with detergent.

Description

installation and process for dry cleaning composite textile articles.

The present invention relates to an installation and a method for dry cleaning composite textile articles.

State of the art

Cut resistant work gloves are made from knitted synthetic yarns (hydrophobic) reinforced with metal threads to achieve cut protection. Certain parts of the gloves may also be coated with a polymer, in particular polyurethane, and/or covered or made of leather or suede. Some cutting aprons are mainly made of bovine leather.

These cutting gloves and other protective textiles are often stained with machining oil.

Cleaning such textiles is therefore difficult on the one hand due to their composite structure which can mix hydrophobic material and hydrophilic material and the presence of machining oil whose formulation is itself complex.

These textiles were classically cleaned with perchlorethylene, the use of which is now strictly regulated and sometimes prohibited in certain countries.

Furthermore, dry cleaning (without the use of water as a solvent or vehicle for cleaning active ingredients) is carried out in special, completely waterproof machines, which allow the recycling of the solvent. These machines are programmable but often suitable for a limited range of cleaners/solvents.

Various documents indicate that it is possible to clean textile work articles without the use of perchlorethylene by improving the mechanical action of the treatment. The grease is removed mechanically rather than by dissolving in a solvent. This is the case, for example, of document CN 208863628.

An aim of the present invention is to provide a dry degreasing installation, in particular for composite textile articles, in particular work gloves, partially covered with mineral grease which can easily be manufactured and at lower cost.

Another aim of the present invention is to provide an installation which is energy efficient.

Another aim of the present invention is to propose a process for dry degreasing of composite textile articles, in particular work gloves, partially covered with mineral grease which does not use perchloroethylene.

Another aim of the present invention is to propose a method such as the aforementioned which can be applied to composite articles comprising leather or suede parts.

Another aim of the present invention is to propose a method such as the aforementioned which can be implemented in a pre-existing installation or using standard cleaning devices.

The present invention relates to a cleaning installation comprising: at least one solvent washing device which comprises: a hermetic circulation circuit, a rotating cleaning/drying drum mounted on said circuit and which is connected by said circuit at the inlet of said drum to a solvent reservoir, the outlet of said drum being connected by said circuit to the boiler of a distillation column, a condenser mounted on said circuit, at the outlet of said distillation column and whose outlet is connected by said hermetic circuit to said solvent reserve, possibly at least one additive reserve connected to said drum and a cooling circuit of said condenser; and at least one tank connected to the outlet of the cooling circuit of the condenser, said tank being connected to a heat exchanger whose outlet is connected to the inlet of the cooling circuit of the condenser; and/or at least one washing machine which comprises a water inlet connected to said tank upstream of said heat exchanger.

The hot water leaving the condenser is cooled in the heat exchanger then reinjected into the condenser cooling circuit to be used again for the condensation of the solvent during the same distillation or during a subsequent distillation. The heat released by the water is used at the heat exchanger to heat the building, for example. When the installation does not include a washing machine, the water in the cooling circuit may contain glycol or be replaced by glycol or any other heat transfer fluid.

The tank is preferably insulated so as to keep the water or other liquid leaving the condenser cooling circuit at a constant temperature.

The water used to condense the distilled solvent is hot. By using this hot water in a washing machine, we save energy and water.

The solvent washing device advantageously comprises means for vaporizing the additive in the drum, which are connected to the additive reserve.

According to a preferred embodiment, the installation comprises two independent solvent washing devices and two independent washing machines, the cooling circuit of each of the devices opens into a heat-insulated storage tank, which is connected to each of said washing machines. wash and part of the water contained in the storage tank is cooled in a heat exchanger to be reinjected into the cooling circuit of the condenser of each of the two solvent washing devices.

In all cases, the cooling water circuit(s) may be supplied by the city water circuit or contain glycol or any other heat transfer fluid. When the heat transfer fluid circulating in the cooling circuit of the condenser(s) is water, the installation advantageously includes at least one washing machine.

The solvent is not limited according to the invention. It is always different from perchlorethylene and mixtures containing perchlorethylene or any other halogenated hydrocarbon.

Thus, according to a particular embodiment, combinable with each of the embodiments of the invention, the solvent reserve contains a solvent chosen from:
- solvents comprising/consisting of a mixture of hydrocarbons free of halogens and containing 11 to 13 carbon atoms, including iso alkanes and less than 2% by mass of aromatic hydrocarbons and a mixture of alkoxylated propanols , said mixture of alkoxylated propanols representing 50% to 70% by mass of said solvent;
- solvents comprising/consisting of 50% to 100% by mass of a mixture of hydrocarbons free of halogens and containing 11 to 14 carbon atoms including iso alkanes and less than 2% by mass of aromatic hydrocarbons, aliphatic hydrocarbons representing at least 30% of the mixture; and their mixtures.

These two solvents give good results in the case of mineral grease on composite articles including leather.

The solvent can therefore contain a surfactant which, due to its amphiphilic nature, makes it possible to clean several types of dirt.

According to a preferred embodiment, combinable with each of the embodiments of the invention, said additive reserve contains an additive chosen from:
- additives comprising/consisting of 25% to 50% by mass of a mixture of a mixture of hydrocarbons free of halogens and containing 11 to 14 carbon atoms including iso alkanes and less than 2% by mass of aromatic hydrocarbons, less than 15% by mass of sodium docusate, less than 10% by mass of alpha hydro omega hydroxy mono alkyl ethers C12-C14 phosphates, less than 5% or 2.5% by mass of ethoxylated isotridecanol, less than 2.5% by mass of 1-amino-propan-2-ol and less than 0.1% alpha hexylcinnamaldehyde; And
- additives comprising/consisting of less than 25% by mass of a mixture of a mixture of hydrocarbons free of halogens and containing 11 to 14 carbon atoms including iso alkanes and less than 2% by mass of aromatic hydrocarbons, less than 15% by mass of sodium docusate, less than 5% by mass of C12-C14 ethoxylated alcohol phosphate, less than 5% or less than 2% by mass of ethoxylated isotridecanol and less than 2 % by mass of 1-amino-propan-2-ol; and their mixtures.

The additive may have a boiling point higher than that of the solvent and in particular the mixture of non-halogenated hydrocarbons constituting or included in the solvent.

In the case of the additive, said surfactant has a boiling point higher than that of the solvent.

According to a preferred embodiment, the installation comprises, upstream of the boiler of said distillation column, a filter provided with at least one magnet. The Applicant has in fact noted that work textiles, in particular cutting gloves, are often contaminated by metal particles which have become embedded in their thickness during use of the glove. These metal particles are likely to clog the solvent circulation circuit and damage the various elements of the dry cleaning device. The particles can also be fragments of the metal wires contained in the gloves. The magnet(s) make it possible to stop the ferrous particles upstream of the distillation column, at the outlet of the drum.

Advantageously, said filter is dimensioned so as to be at least partially filled with said solvent leaving said drum for the majority of the duration of flow of said solvent towards said column to be distilled and said magnet(s) are arranged so as to be immersed in the volume of solvent contained in said filter. Since the particles float in the solvent contained in the filter, they are easily attracted to the magnet(s). The magnet(s) are preferably removable in order to easily remove the particles covering them before their reuse.

The filter is not limited according to the invention. Its openings and their number are selected according to the flow of solvent leaving the drum. The filter is advantageously concave, which allows the immersion of the magnet(s) when the latter, for example, are simply placed on the bottom of the filter.

Majority of flow time means that for at least half of the flow time, the liquid immerses the magnet(s). Advantageously, the filter fills so as to immerse the magnet(s) and the outgoing flow/incoming flow ratio is such that the magnet(s) remain immersed until the filter empties when the incoming flow is zero.

Advantageously, said circulation circuit comprises a gravimetric solid/liquid separator which is connected at the outlet to the boiler of the distillation column and at the inlet to the outlet of the drum. This separator makes it possible to separate the liquid from the solid particles it contains. Solid particles come, for example, from the attrition of textiles; These are pieces of textile or leather.

Advantageously, said circulation circuit comprises a gravimetric liquid/liquid separator connected to the solid/liquid separator and which allows the separation between an aqueous phase and an organic phase. This separator makes it possible to treat the aqueous phase which forms when the treated composite textiles contain hydrophilic portions, such as leather or suede for example.

It is indeed the merit of the Applicant to have noted that an aqueous phase forms during the treatment despite the absence of introduction of liquid water into the circulation circuit. This water comes from the hydrophilic portions of the textiles; it binds to the surfactant of the additive and forms an aqueous phase heavier than the solvent and which can be treated in the installation of the invention.

Advantageously, said liquid/liquid separator comprises mixing means and is connected to a reserve of mineral salt, in particular NaCl. Adding salt breaks the emulsion and accelerates phase separation.

The present invention also relates to a dry degreasing process, in particular for composite textile articles, in particular work gloves, partially covered with mineral grease. Characteristically, according to the process of the invention, said articles are soaked with a solvent consisting of a mixture of halogen-free alkanes and then an additive comprising or consisting of a mixture is optionally sprayed onto said soaked articles. of aliphatic hydrocarbons free of halogen and/or at least one nonionic and/or cationic surfactant and having a boiling temperature higher than that of said solvent, a mechanical action is exerted on said articles, in particular said articles are mixed, said articles are then drained, the liquid mixture resulting from the spinning is distilled so as to separate said solvent, the water used for the condensation of the distilled solvent is cooled and it is reused for the condensation of the solvent after the distillation and/or the water used for the distillation and which is therefore at a temperature above room temperature is used to wash other textile articles with a detergent.

According to one mode of implementation of the method of the invention, said articles to be treated comprise leather and/or suede parts at least partially covered with a mineral oil.

The solvent is not limited according to the invention. It is in all cases free of halogenated hydrocarbons and any halogen.

The solvent can advantageously be chosen from:
- solvents comprising/consisting of a mixture of hydrocarbons free of halogens and containing 11 to 13 carbon atoms, including iso alkanes and less than 2% by mass of aromatic hydrocarbons and a mixture of alkoxylated propanols , said mixture of alkoxylated propanols representing 50% to 70% by mass of said solvent;
- solvents comprising/consisting of 50% to 100% by mass of a mixture of hydrocarbons free of halogens and containing 11 to 14 carbon atoms including iso alkanes and less than 2% by mass of aromatic hydrocarbons, aliphatic hydrocarbons representing at least 30% of the mixture; and their mixtures. ,

Said additive is advantageously chosen from:
- additives comprising/consisting of 25% to 50% by mass of a mixture of a mixture of hydrocarbons free of halogens and containing 11 to 14 carbon atoms including iso alkanes and less than 2% by mass of aromatic hydrocarbons, less than 15% by mass of sodium docusate, less than 10% by mass of alpha hydro omega hydroxy mono alkyl ethers C12-C14 phosphates, less than 5% or 2.5% by mass of ethoxylated isotridecanol, less than 2.5% by mass of 1-amino-propan-2-ol and less than 0.1% alpha hexylcinnamaldehyde; And
- additives comprising/consisting of less than 25% by mass of a mixture of a mixture of hydrocarbons free of halogens and containing 11 to 14 carbon atoms including iso alkanes and less than 2% by mass of aromatic hydrocarbons, less than 15% by mass of sodium docusate, less than 5% by mass of C12-C14 ethoxylated alcohol phosphate, less than 5% or less than 2% by mass of ethoxylated isotridecanol and less than 2 % by mass of 1-amino-propan-2-ol; and their mixtures.

The additive is preferably used when the solvent does not contain alkoxylated propanols.

The solvent may advantageously have a boiling point equal to or greater than 170°C, in particular equal to 180°C and less than or equal to 190°C, a flash point greater than or equal to 61°C, in particular equal to 65°C. C, and less than or equal to 72°C, a saturated vapor pressure at 20°C greater than or equal to 45 Pa and in particular equal to 54 Pascal and less than or equal to 65 Pa, a density less than that of water and notably equal to 0.84 g/cm ³ and a KB value measured according to the ASTM standard (Method D-1133) of 161.

The additive preferably has a flash point above 61°C.

Definitions

For the purposes of the invention, a machining oil comprises or consists of a mixture of saturated or aromatic hydrocarbons comprising from 15 to 40 carbon atoms and not comprising a halogen atom. A mineral oil can also be an aqueous emulsion (oil in water or water in oil) and contain various active agents including bactericides and antifoaming agents, for example.

The term “isotridecanol” refers to 11-methyl dodecan-1-ol.

The terms “ethoxylated isotridecanol” refer to the reaction product between 11-methyl dodecan-1-ol and ethylene oxide.

For the purposes of the invention, dry cleaning designates cleaning using a solvent or vehicle other than water.

Brief description of the figures

The characteristics and advantages of the invention will appear on reading the following description based on the :
there schematically represents an embodiment of the invention;

detailed description

In reference to the , a particular embodiment of the installation of the invention will now be described.

The installation comprises a sealed dry cleaning device containing a rotating drum 1, a solvent tank 12 and an additive reserve 14. The additive reserve 14 and the solvent reserve 12 are connected to the drum 1 by pipes equipped with controllable solenoid valves. The cleaning device is equipped with a spray nozzle (not shown) which allows the additive contained in the reserve 12 to be sprayed into the drum 1, in particular when the latter is rotating. The drum 1 also allows the articles to be drained once they have been soaked with the solvent and the additive and have been sufficiently mixed in the drum 1. The liquid extracted by centrifugation from the drum 1 passes through the pipe 3 and falls into a filter 5 which contains a magnet 7. This magnet 7 makes it possible to retain all the particles of ferrous material which have been extracted from the articles. This avoids blocking the pipes of the device. The liquid leaving the filter 5 is sent to a gravimetric solid/liquid separator 8. The separator 8 is connected to the boiler 95 of the distillation column 9. The cooling circuit of the condenser 93 of the distillation column 9 is supplied with water coming from the city network. This water therefore circulates in a circuit separate from the hermetic circulation circuit which connects the drum 1, the reserves 12 and 14, the boiler 95, the distillation column 9, the condenser 93 and the two separators 8 and 81. It is not therefore never in contact with the solvent but heats up on contact in the condenser 93, then causing condensation of the solvent. The outlet of the condenser 93 is connected to the tank 12 and/or to the inlet of the boiler 95 of the distillation column 9. The solid/liquid separator 8 is connected to a liquid/liquid separator 81. The upper part of the liquid/liquid separator liquid 81 is connected to the solvent reserve 12 and/or to the boiler 95 of the distillation column 9. (these connections via pipes not shown, for the sake of clarity, are indicated by stars on the ).

The cooling water circuit of condenser 93 is indicated in dotted lines on the . The outlet of the cooling circuit of the condenser 93 is connected to a heat-insulated tank 55, which is connected to a washing machine 56. The heat-insulated tank 55 is connected to a heat exchanger 67 which makes it possible to cool the water contained in the tank 55 The outlet of the heat exchanger 67 is connected to the inlet of the cooling circuit of the condenser 93. The connection is symbolized by two stars.

All flow adjustment valves have been omitted from Figure 1 for clarity.

The filter 5 has a concave shape and the magnet 7 is arranged so as to be at least partially immersed by the liquid leaving the drum 1, this in order to facilitate the capture of ferrous particles by the magnet 7.

The process of the invention will now be described with reference to the . The method of the invention and the installation of the invention are particularly suitable for cleaning work gloves, in particular anti-cut cutting gloves which have leather parts. Leather is a hydrophilic material that retains water to a certain extent.

The gloves are introduced into the drum 1. The solvent coming from the reserve 12 is introduced into the drum 1. The drum is rotated so as to soak the gloves. The additive is then sprayed onto the soaked gloves. We continue to mix the gloves in drum 1. Mixing limits wear on the textiles and allows the gloves to be reused and cleaned several times. After a given period of time that a person skilled in the art is capable of determining by experiment, the gloves are wrung out, which are then removed from the drum and possibly dried if necessary. The liquid leaving the drum is therefore a mixture of the solvent, the additive, water entrained by the surfactant of the additive, metal, textile and/or leather particles. The outgoing liquid is poured onto the filter 5. The liquid surrounding the magnet 7, the ferrous particles in suspension easily stick to the magnet 7. The filtered liquid is introduced into the solid/liquid separator 8 which allows it to be removed sludge formed by solid particles and pieces of textiles. The liquid phase is sent to the boiler 95 of the distillation column 9. The temperature in the distillation column 9 is such that it allows the evaporation of the solvent or at least of the hydrocarbon mixture it contains. The solvent is then condensed in the condenser 93 and returned to the solvent reserve 12 or to the boiler 95 of the distillation column 9 for a second distillation. The cooling water leaving the condenser 93 is sent to the heat-insulated tank 55 or passes through the latter to reach the washing machine 56. The water not used for the washing machine 56 passes through the heat exchanger 67 , cools there and is sent to the inlet of the cooling circuit of condenser 93.

The mixture remaining at the bottom of the column after distillation of the solvent is introduced into a gravimetric liquid/liquid separator 81. A phase separation then appears. At the bottom of separator 81 we find an aqueous phase containing the surfactant of the additive while the upper phase still contains solvent. The upper phase is sent to the boiler 95 or to the solvent reserve 12. It is also possible to connect the liquid/liquid separator 81 to a reserve of salt(s) (not shown). The addition of salt makes it possible to promote and accelerate the phase separation in the liquid/liquid separator 81. In this case, the separator 81 also includes mixing means and becomes a mixer/decanter.

The durations of the treatments, the flow rates of the solvent and the additive, the quantity of textiles treated, the temperatures and pressure are adjustable experimentally by those skilled in the art.

Claims (3)

Dry degreasing process, in particular for composite textile articles, in particular work gloves, partially covered with mineral grease, characterized in that said articles are impregnated with a first solvent comprising/consisting of a mixture of alkanes halogen-free then in that said soaked articles are optionally sprayed with an additive comprising or consisting of a mixture of halogen-free aliphatic hydrocarbons and/or at least one non-ionic surfactant and/or cationic and having a boiling temperature higher than that of said solvent, in that a mechanical action is exerted on said articles, in particular in that said articles are stirred, in that said articles are then drained, in that the liquid mixture resulting from the spinning is distilled so as to separate at least said first solvent and in that the water used for the condensation of the distilled solvent is cooled and in that it is reused for the condensation of the solvent after the distillation and/or in that the water used for the distillation and which is therefore at a temperature above ambient temperature is used to wash other textile articles with a detergent. Method according to claim 1, characterized in that said articles to be treated comprise parts of leather and/or suede at least partially covered with a mineral oil. Process according to claim 1 or 2, characterized in that said solvent is chosen from:
- solvents comprising/consisting of a mixture of hydrocarbons free of halogens and containing 11 to 13 carbon atoms, including iso alkanes and less than 2% by mass of aromatic hydrocarbons and a mixture of alkoxylated propanols , said mixture of alkoxylated propanols representing 50% to 70% by mass of said solvent;
- solvents comprising/consisting of 50% to 100% by mass of a mixture of hydrocarbons free of halogens and containing 11 to 14 carbon atoms including iso alkanes and less than 2% by mass of aromatic hydrocarbons, aliphatic hydrocarbons representing at least 30% of the mixture; and their mixtures,
and/or in that said additive is chosen from:
- additives comprising/consisting of 25% to 50% by mass of a mixture of a mixture of hydrocarbons free of halogens and containing 11 to 14 carbon atoms including iso alkanes and less than 2% by mass of aromatic hydrocarbons, less than 15% by mass of sodium docusate, less than 10% by mass of alpha hydro omega hydroxy mono alkyl ethers C12-C14 phosphates, less than 5% or 2.5% by mass of ethoxylated isotridecanol, less than 2.5% by mass of 1-amino-propan-2-ol and less than 0.1% alpha hexylcinnamaldehyde; And
- additives comprising/consisting of less than 25% by mass of a mixture of a mixture of hydrocarbons free of halogens and containing 11 to 14 carbon atoms including iso alkanes and less than 2% by mass of aromatic hydrocarbons, less than 15% by mass of sodium docusate, less than 5% by mass of C12-C14 ethoxylated alcohol phosphate, less than 5% or less than 2% by mass of ethoxylated isotridecanol and less than 2 % by mass of 1-amino-propan-2-ol; and their mixtures.