installation and process for dry cleaning composite textile articles.

Abstract

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

Description

Title of the invention: Installation and method for dry cleaning composite textile articles. technical field

[0001] The present invention relates to an installation and a method for dry cleaning composite textile articles. State of the art

[0002] Cut-resistant work gloves are made from knitted synthetic (hydrophobic) yarns reinforced with metallic threads to provide cut protection. Certain parts of the gloves may also be coated with a polymer, particularly polyurethane, and / or covered with or made of leather or suede. Some cutting aprons are made primarily of bovine leather.

[0003] These cutting gloves and other protective textiles are often stained with machining oil.

[0004] Cleaning such textiles is therefore difficult on the one hand because of their composite structure which can mix hydrophobic and hydrophilic material and the presence of machining oil whose formulation is itself complex.

[0005] These textiles were traditionally cleaned with perchloroethylene, the use of which is now strictly regulated and sometimes prohibited in certain countries.

[0006] Furthermore, dry cleaning (without the use of water as a solvent or vehicle for the cleaning agents) is carried out in special, completely sealed machines that allow for solvent recycling. These machines are programmable but often adapted to a limited range of cleaning products / solvents.

[0007] Various documents indicate that it is possible to clean work textiles without the use of perchloroethylene by improving the mechanical action of the treatment. The grease is removed mechanically rather than by dissolution in a solvent. This is the case, for example, in document CN 208863628.

[0008] An object of the present invention is to provide a dry degreasing installation, in particular for composite textile articles, especially work gloves, partially coated with mineral grease, which can be easily manufactured and at a lower cost.

[0009] Another object of the present invention is to provide an installation that is energy efficient.

[0010] Another object of the present invention is to propose a dry degreasing process for composite textile articles, in particular work gloves, partially coated with mineral grease which does not use perchloroethylene.

[0011] Another object of the present invention is to propose a method such as the one mentioned above which can be applied to composite articles comprising parts made of leather or suede.

[0012] Another object of the present invention is to propose a method such as the above-mentioned which can be implemented in a pre-existing installation or using standard cleaning devices. Summary of the invention

[0013] The present invention relates to a cleaning installation comprising: at least one solvent washing device which includes: a hermetically sealed circulation circuit, a rotating cleaning / spinning drum mounted on said circuit and 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 hermetically sealed circuit to said solvent reservoir, optionally at least one additive reservoir connected to said drum and a cooling circuit for said condenser; and at least one tank connected to the outlet of the condenser cooling circuit, said tank being connected to a heat exchanger whose outlet is connected to the inlet of the condenser cooling circuit;and / or at least one washing machine which includes a water inlet connected to said tank upstream of said heat exchanger.

[0014] The hot water exiting the condenser is cooled in the heat exchanger and then reintroduced into the inlet of the condenser cooling circuit to be used again for solvent condensation during the same distillation or 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.

[0015] The tank is preferably insulated so as to keep the water or other liquid exiting the condenser cooling circuit at a constant temperature.

[0016] The water used to condense the distilled solvent is hot. Using this hot water in a washing machine saves energy and water.

[0017] The solvent washing device advantageously includes means for vaporizing the additive in the drum, which are connected to the additive reservoir.

[0018] According to a preferred embodiment, the installation comprises two independent solvent washing devices and two independent washing machines, the cooling circuit of each device draining into an insulated storage tank, which is connected to each of said washing machines and a portion 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.

[0019] In all cases, the cooling water circuit(s) may be supplied by the mains water supply 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.

[0020] The solvent is not limited according to the invention. It is always different from perchloroethylene and mixtures containing perchloroethylene or any other halogenated hydrocarbon.

[0021] Thus, according to a particular embodiment, combinable with each of the embodiments of the invention, the solvent reserve contains a solvent selected from: - solvents comprising / consisting of a mixture of halogen-free hydrocarbons containing 11 to 13 carbon atoms, including isoalkanes 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 halogen-free hydrocarbons and containing 11 to 14 carbon atoms including isoalkanes and less than 2% by mass of aromatic hydrocarbons, with aliphatic hydrocarbons representing at least 30% of the mixture; and mixtures thereof.

[0022] These two solvents give good results in the case of mineral grease on composite articles including leather.

[0023] The solvent may therefore contain a surfactant which, due to its amphiphilic nature, allows it to clean several types of soiling.

[0024] According to a preferred embodiment, combinable with each of the embodiments of the invention, said additive reservoir contains an additive selected from: - additives comprising / consisting of 25% to 50% by mass of a mixture of halogen-free hydrocarbons containing 11 to 14 carbon atoms, including isoalkanes, and less than 2% by mass of aromatic hydrocarbons, less than 15% by mass of sodium docusate, less than 10% by mass of C12-C14 alpha-hydroxy omega-hydroxy monoalkyl ether phosphates, less than 5% or 2.5% by mass of ethoxylated isotridecanol, less than 2.5% by mass of l-aminopropane-2-ol, and less than 0.1% of alpha-hexylcinnamaldehyde; and - additives comprising / constituted of less than 25% by mass of a mixture of halogen-free hydrocarbons containing 11 to 14 carbon atoms including isoalkanes and less than 2% by mass of hydrocarbons aromatics, 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 l-aminopropane-2-ol; and mixtures thereof.

[0025] The additive may have a boiling point higher than that of the solvent and in particular than the mixture of non-halogenated hydrocarbons constituting or included in the solvent.

[0026] In the case of the additive, said surfactant has a boiling point higher than that of the solvent.

[0027] According to a preferred embodiment, the installation includes, upstream of the distilling column's boiler, a filter equipped with at least one magnet. The Applicant has observed that work textiles, particularly cutting gloves, are often contaminated by metallic particles that become embedded in their thickness during glove use. These metallic particles can clog the solvent circulation circuit and damage the various components of the dry cleaning device. The particles may also be fragments of the metallic threads contained within the gloves. The magnet(s) stop the ferrous particles upstream of the distilling column, at the drum outlet.

[0028] Advantageously, the filter is sized so as to be at least partially filled with the solvent exiting the drum for most of the time during which the solvent flows to the distillation column, and the magnet(s) are arranged so as to be immersed in the volume of solvent contained in the 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 so as to easily remove any particles coating them before reuse.

[0029] The filter is not limited according to the invention. Its openings and their number are selected according to the solvent flow rate exiting the drum. The filter is advantageously concave, which allows the immersion of the magnet(s) when they are, for example, simply placed on the bottom of the filter.

[0030] The majority of the flow time means that for at least half of the flow time, the liquid immerses the magnet(s). Advantageously, the filter fills in such a way as to immerse the magnet(s), and the outflow / inflow ratio is such that the magnet(s) remain immersed until the filter empties when the inflow is zero.

[0031] Advantageously, said circulation circuit includes a solid / liquid gravimetric separator which is connected at the outlet to the reboiler of the distillation column and at the inlet to the outlet of the drum. This separator allows, in particular, the separation of the liquid from the solid particles it contains. The solid particles come, for example, from the attrition of textiles; they are pieces of textile or leather.

[0032] Advantageously, said circulation circuit includes a liquid / liquid gravimetric separator connected to the solid / liquid separator, which allows the separation between an aqueous phase and an organic phase. This separator makes it possible to treat the aqueous phase that forms when the treated composite textiles contain hydrophilic portions, such as leather or suede, for example.

[0033] It is indeed to the Applicant's credit that she observed that an aqueous phase forms during the treatment despite the absence of liquid water being introduced into the circulation circuit. This water originates from the hydrophilic portions of the textiles; it binds to the surfactant of the additive and forms an aqueous phase that is heavier than the solvent and that can be treated in the installation of the invention.

[0034] Advantageously, said liquid / liquid separator includes mixing means and is connected to a mineral salt reservoir, in particular NaCl. The addition of salt breaks the emulsion and accelerates phase separation.

[0035] The present invention also relates to a dry degreasing process, in particular for composite textile articles, especially work gloves, partially coated 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, then an additive comprising or consisting of a mixture of halogen-free aliphatic hydrocarbons and / or at least one non-ionic and / or cationic surfactant and having a boiling point higher than that of said solvent is optionally sprayed onto said soaked articles, a mechanical action is exerted on said articles, in particular, said articles are agitated, said articles are then wrung out, the liquid mixture resulting from wringing is distilled so as to separate said solvent, the water used for the condensation of the distilled solvent is cooled and reused for the condensation of the solvent after distillation and / or the water used for distillation, which is therefore at a temperature higher than ambient temperature, is used to wash other textile articles with a detergent.

[0036] According to one embodiment of the process of the invention, said articles to be treated comprise parts of leather and / or suede at least partially covered with a mineral oil.

[0037] The solvent is not limited according to the invention. It is in all cases free from halogenated hydrocarbons and any halogen.

[0038] The solvent can advantageously be chosen from: - solvents comprising / composed of a mixture of halogen-free hydrocarbons containing 11 to 13 carbon atoms, including isoalkanes and less of 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 / constituted from 50% to 100% by mass of a mixture of halogen-free hydrocarbons containing 11 to 14 carbon atoms, including isoalkanes, and less than 2% by mass of aromatic hydrocarbons, with aliphatic hydrocarbons representing at least 30% of the mixture; and mixtures thereof.

[0039] Said additive is advantageously chosen from: - additives comprising / consisting of 25% to 50% by mass of a mixture of halogen-free hydrocarbons containing 11 to 14 carbon atoms, including isoalkanes, and less than 2% by mass of aromatic hydrocarbons, less than 15% by mass of sodium docusate, less than 10% by mass of C12-C14 alpha-hydroxy omega-hydroxy monoalkyl ether phosphates, less than 5% or 2.5% by mass of ethoxylated isotridecanol, less than 2.5% by mass of l-aminopropane-2-ol, and less than 0.1% of alpha-hexylcinnamaldehyde; and - additives comprising / consisting of less than 25% by mass of a mixture of halogen-free hydrocarbons containing 11 to 14 carbon atoms including isoalkanes 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 l-aminopropane-2-ol; and mixtures thereof.

[0040] The additive is preferably used when the solvent does not contain alkoxylated propanols.

[0041] The solvent may advantageously have a boiling point of 170°C or higher, in particular 180°C or higher and less than or equal to 190°C, a flash point of 61°C or higher, in particular 65°C or higher and less than or equal to 72°C, a saturated vapor pressure at 20°C of 45 Pa or higher and in particular 54 Pascal or lower than or equal to 65 Pa, a density lower than that of water and in particular 0.84 g / cm3 and a KB value measured according to ASTM Standard (Method D-1133) of 161.

[0042] The additive preferably has a flash point above 61°C.

[0043] Definitions

[0044] For the purposes of the invention, a machining oil comprises or is made up of a mixture of saturated or aromatic hydrocarbons comprising 15 to 40 carbon atoms and not comprising any halogen atoms. A mineral oil may also be a aqueous emulsion (oil in water or water in oil) and contain various active agents including bactericides and antifoaming agents, for example.

[0045] The term “isotridecanol” refers to 11-methyl dodecanol.

[0046] The terms "ethoxylated isotridecanol" refer to the reaction product between 11-methyldodecanol and ethylene oxide.

[0047] For the purposes of the invention, dry cleaning means cleaning by using a solvent or vehicle other than water. Brief description of the figures

[0048] The features and advantages of the invention will become apparent from the following description, which is based on [Fig. 1]: [Fig. 1] schematically represents an embodiment of the invention; Detailed description

[0049] With reference to [Fig.1], a particular embodiment of the installation of the invention will now be described.

[0050] The installation includes a sealed dry cleaning device containing a rotating drum 1, a solvent reservoir 12, and an additive reservoir 14. The additive reservoir 14 and the solvent reservoir 12 are connected to the drum 1 by lines fitted with controllable solenoid valves. The cleaning device is equipped with a spray nozzle (not shown) that allows the additive contained in the reservoir 12 to be sprayed into the drum 1, particularly when the drum is rotating. The drum 1 also allows the articles to be wrung out once they have been soaked with the solvent and the additive and have been sufficiently agitated in the drum 1. The liquid extracted by centrifugation from the drum 1 passes through the line 3 and falls into a filter 5 containing a magnet 7. This magnet 7 retains all the ferrous particles that have been extracted from the articles. This prevents the lines of the device from clogging.The liquid exiting filter 5 is sent to a solid / liquid gravimetric separator 8. The separator 8 is connected to the reboiler 95 of the distillation column 9. The cooling circuit of the condenser 93 of the distillation column 9 is supplied with water from the municipal water supply. This water therefore circulates in a circuit separate from the hermetically sealed circulation circuit that connects the drum 1, the reservoirs 12 and 14, the reboiler 95, the distillation column 9, the condenser 93, and the two separators 8 and 81. It is thus never in contact with the solvent but is heated by contact with it in the condenser 93, causing the solvent to condense. The outlet of the condenser 93 is connected to the reservoir 12 and / or to the inlet of the reboiler 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 81 is connected to the solvent reservoir 12 and / or to the reboiler 95 of the distillation column 9. (these connections via . Conduits not shown, for the sake of clarity, are indicated by stars on [Fig. 1].

[0051] The condenser cooling water circuit 93 is shown in dashed lines in [Fig. 1]. The outlet of the condenser cooling circuit 93 is connected to an insulated tank 55, which is connected to a washing machine 56. The insulated tank 55 is connected to a heat exchanger 67 that cools the water contained in the tank 55. The outlet of the heat exchanger 67 is connected to the inlet of the condenser cooling circuit 93. The connection is symbolized by two stars.

[0052] All flow control valves have been omitted from diagram 1 for clarity.

[0053] The filter 5 has a concave shape and the magnet 7 is arranged so as to be at least partially immersed by the liquid exiting the drum 1, in order to facilitate the capture of ferrous particles by the magnet 7.

[0054] The method of the invention will now be described with reference to [Fig. 1]. The method and apparatus of the invention are particularly suited to cleaning work gloves, especially cut-resistant cutting gloves that have leather parts. Leather is a hydrophilic material that retains water to a certain extent.

[0055] The gloves are placed in drum 1. The solvent from reservoir 12 is introduced into drum 1. The drum is rotated to saturate the gloves. The additive is then sprayed onto the saturated gloves. The gloves continue to be agitated in drum 1. This agitation limits wear on the textiles and allows the gloves to be reused and cleaned several times. After a specified time, which a person skilled in the art can determine experimentally, the gloves are wrung out and then removed from the drum and, if necessary, dried. The liquid exiting the drum is therefore a mixture of the solvent, the additive, water carried along by the surfactant in the additive, and metallic, textile, and / or leather particles. The exiting liquid is poured onto the filter 5. As the liquid surrounds the magnet 7, the suspended ferrous particles readily adhere to the magnet 7.The filtered liquid is introduced into the solid / liquid separator 8, which removes the sludge formed by solid particles and textile fragments. The liquid phase is then sent to the reboiler 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 the hydrocarbon mixture it contains. The solvent is then condensed in the condenser 93 and returned to the solvent reservoir 12 or to the reboiler 95 of the distillation column 9 for a second distillation. The cooling water leaving the condenser 93 is sent to the insulated tank 55 or passes through it before reaching the machine. washing machine 56. The water not used for the washing machine 56 passes through the heat exchanger 67, is cooled there and is sent to the inlet of the condenser cooling circuit 93.

[0056] The mixture remaining at the bottom of the column after solvent distillation is introduced into a liquid / liquid gravimetric separator 81. Phase separation then occurs. At the bottom of the separator 81, an aqueous phase containing the surfactant of the additive is found, while the upper phase still contains solvent. The upper phase is sent to the reboiler 95 or to the solvent reservoir 12. It is also possible to connect the liquid / liquid separator 81 to a salt reservoir (not shown). The addition of salt promotes and accelerates phase separation in the liquid / liquid separator 81. In this case, the separator 81 also includes mixing means and becomes a mixer / decanter.

[0057] The duration 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 a person skilled in the art.

Claims

Demands

1. A dry degreasing process for composite textile articles partially coated with mineral grease, characterized in that said articles are soaked with a solvent comprising a mixture of halogen-free alkanes and then sprayed onto said soaked articles an additive comprising a mixture of halogen-free aliphatic hydrocarbons and / or at least one non-ionic and / or cationic surfactant having a boiling point higher than that of said solvent, in that a mechanical action is exerted on said articles, in that said articles are then wrung out, in that the liquid mixture resulting from wringing is distilled so as to separate at least said solvent,in that water used for the condensation of the distilled solvent is cooled and the cooled water is reused for the condensation of the solvent after distillation and / or in that the water used for distillation, which is therefore at a temperature higher than ambient temperature, is used to wash other textile articles with detergent.

2. A 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.

3. A process according to claim 1 or 2, characterized in that said solvent is selected from: - solvents comprising a mixture of halogen-free hydrocarbons containing 11 to 13 carbon atoms, including isoalkanes 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 50% to 100% by mass of a mixture of halogen-free hydrocarbons containing 11 to 14 carbon atoms, including isoalkanes and less than 2% by mass of aromatic hydrocarbons, aliphatic hydrocarbons representing at least 30% of the mixture; and mixtures thereof.

4. A process according to claim any one of claims 1 to 3, characterized in that said additive is selected from: - additives comprising 25% to 50% by mass of a mixture of halogen-free hydrocarbons and containing 11 to 14 carbon atoms including isoalkanes and less than 2% by mass of aromatic hydrocarbons, less than 15% by mass of sodium docusate, less than 10% by mass of C12-C14 alpha-hydro omega-hydroxy monoalkyl ether phosphates, less than 5% or 2.5% by mass of ethoxylated isotridecanol, less than 2.5% by mass of l-aminopropane-2-ol and less than 0.1% of alpha-hexylcinnamaldehyde; and - additives comprising less than 25% by mass of a mixture of halogen-free hydrocarbons containing 11 to 14 carbon atoms including isoalkanes 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 l-aminopropane-2-ol; and mixtures thereof.

Images