Method and apparatus for the wet treatment of laundry articles

Abstract

In the washing and drainage of laundry articles, treatment liquid which contains still unspent wash-active substances occurs at the end of the washing operation. These substances have hitherto been conducted, if appropriate after neutralization, into the discharge together with the treatment liquid. This known procedure has an adverse effect on the efficiency of the washing operation. According to the invention, spent wash-active substances are removed from the treatment liquid separated from the laundry articles after the washing operation. This takes place by means of precision filtration, in which only the spent wash-active substances which are larger due to the absorption of dirt from the washing operation are filtered out of the treatment liquid, but not the unspent wash-active substances having a smaller particle size. These can be reused, together with the treatment liquid, for a subsequent washing operation.

1 . Method for the wet treatment of laundry articles, the laundry articles being at least washed in a treatment liquid containing at least one wash-active substance, and thereafter the treatment liquid being at least partially separated from the treated laundry articles, wherein spent wash-active substances are removed at least for the most part from the treatment liquid separated from the laundry articles. 
   
   
       2 . Method according to  claim 1 , wherein at least one spent wash-active substance is removed at least for the most part from the treatment liquid after different treatment steps. 
   
   
       3 . Method according to  claim 1 , wherein the at least one spent wash-active substance is removed at least for the most part from the treatment liquid after at least one pre-wash. 
   
   
       4 . Method according to  claim 1 , wherein the at least one spent wash-active substance is removed at least for the most part from the treatment liquid a plurality of times. 
   
   
       5 . Method according to  claim 1 , wherein, during a rinsing of the washed laundry articles in a drainage device, at least one spent wash-active substance is removed at least for the most part from the treatment liquid separated from the laundry articles after washing and also from the treatment liquid separated from the laundry articles before rinsing in the drainage device. 
   
   
       6 . Method according to  claim 1 , wherein the at least one spent wash-active substance is separated at least for the most part from the treatment liquid by filtration. 
   
   
       7 . Method according to  claim 6 , wherein pre-filtration is carried out before at least one spent wash-active substance is filtered out of the treatment liquid. 
   
   
       8 . Method according to  claim 6 , wherein the filtering-out of at least a large part of at least one spent wash-active substance from the treatment liquid takes place by means of micro-filtration. 
   
   
       9 . Method according to  claim 6 , wherein, during filtration, spent wash-active substances with a particle size of 0.005 μm to 10 μm are removed at least for the most part from the treatment liquid. 
   
   
       10 . Method for the wet treatment of laundry articles, the laundry articles being at least washed in a treatment liquid containing at least one wash-active substance, and thereafter the treatment liquid being separated at least partially from the laundry articles, wherein, during treatment, the content of the at least one wash-active substance still contained in the treatment liquid is determined. 
   
   
       11 . Method according to  claim 10 , wherein, after the removal of at least a large part of spent wash-active substances from the treatment liquid, the content of at least one wash-active substance still contained in the treatment liquid is determined. 
   
   
       12 . Method according to  claim 10 , wherein the measured content of the at least one wash-active substance still contained in the treatment liquid is compared with a desired content of the respective wash-active substance in the treatment liquid, and, if the desired content is undershot, a corresponding quantity of at least one wash-active substance is added to the treatment liquid. 
   
   
       13 . Apparatus for the wet treatment of laundry articles, with a washing machine having a drum ( 13 ) drivable in rotation and with a drainage device following the washing machine, wherein at least one filter ( 52 ,  57 ) for removing at least one spent wash-active substance in the treatment liquid is assigned to an outflow line, returned to the start of a washing zone ( 47 ,  48 ) for the treatment liquid from the drum ( 13 ) and to an outflow line, returned to the start of the washing zone ( 47 ,  48 ) from the drainage device. 
   
   
       14 . Apparatus for the wet treatment of laundry articles with a washing machine having a drum ( 13 ) drivable in rotation and with a drainage device following the washing machine, wherein at least one filter ( 26 ,  32 ) for the removal of at least one spent wash-active substance from the treatment liquid is assigned to at least one outflow line, returned to the start of the washing zone ( 17 ,  18 ) for treatment liquid from the drum ( 13 ). 
   
   
       15 . Apparatus according to  claim 13 , wherein at least one pre-filter ( 25 ,  31 ,  51 ,  56 ) is arranged upstream of the filter ( 26 ,  32 ,  52 ,  57 ) for removing at least one spent wash-active substance from the treatment liquid. 
   
   
       16 . Apparatus according to  claim 15 , wherein the filter ( 26 ,  32 ,  52 ,  57 ) is designed as a micro-filter. 
   
   
       17 . Apparatus according to  claim 15 , wherein the filter ( 26 ,  32 ,  52 ,  57 ) is designed as a membrane filter. 
   
   
       18 . Apparatus according to  claim 17 , wherein the membrane filter is assigned at least one supporting body. 
   
   
       19 . Apparatus according to  claim 14 , wherein at least one pre-filter ( 25 ,  31 ,  51 ,  56 ) is arranged upstream of the filter ( 26 ,  32 ,  52 ,  57 ) for removing at least one spent wash-active substance from the treatment liquid. 
   
   
       20 . Apparatus according to  claim 19 , wherein the filter ( 26 ,  32 ,  52 ,  57 ) is designed as a micro-filter. 
   
   
       21 . Apparatus according to  claim 19 , wherein the filter ( 26 ,  32 ,  52 ,  57 ) is designed as a membrane filter. 
   
   
       22 . Apparatus according to  claim 21 , wherein the membrane filter is assigned at least one supporting body.