Installation and process for recycling wiping solution of one or more intaglio printing presses

Abstract

There is described an installation ( 01; 02 ) for recycling wiping solution of one or more intaglio printing presses ( 10 ) comprising a flocculation tank ( 12 ) for inducing flocculation of ink constituents contained in waste solution coming from the one or more intaglio printing presses ( 10 ), a processing tank ( 14 ) for pre-treating the waste solution for subsequent filtering, and a filtering unit ( 15 ), preferably a filter press unit, for filtering the waste solution coming from the processing tank ( 14 ) and producing recycled solution at an output of the filtering unit ( 15 ), which recycled solution is recycled to produce fresh wiping solution for use by the one or more intaglio printing presses ( 10 ). According to one embodiment, the installation ( 01 ) further comprises a centrifugation unit ( 13 ) for separating the waste solution coming from the flocculation tank ( 12 ) by centrifugation into precipitate and centrifuged supernatant, which centrifuged supernatant is fed to the processing tank ( 14 ). According to a second embodiment, the installation ( 02 ) further comprises a decantation unit ( 13 a ) for separating the waste solution coming from the flocculation tank ( 12 ) by decantation into precipitate and decanted supernatant, which decanted supernatant is fed to the processing tank ( 14 ), and a centrifugation unit ( 13 b ) for further separating the precipitate produced by the decantation unit ( 13 a ) by centrifugation into further precipitate and centrifuged supernatant, which centrifuged supernatant is fed to the processing tank ( 14 ). There are also described corresponding processes for recycling wiping solution.

1 . An installation for recycling wiping solution of one or more intaglio printing presses, comprising:
 a flocculation tank for inducing flocculation of ink constituents contained in waste solution coming from the one or more intaglio printing presses;   a centrifugation unit for separating the waste solution coming from the flocculation tank by centrifugation into precipitate and centrifuged supernatant;   a processing tank for pre-treating the centrifuged supernatant coming from the centrifugation unit for subsequent filtering; and   a filtering unit for filtering the waste solution coming from the processing tank and producing recycled solution at an output of the filtering unit, which recycled solution is recycled to produce fresh wiping solution for use by the one or more intaglio printing presses.   
     
     
         2 . An installation for recycling wiping solution of one or more intaglio printing presses, comprising:
 a flocculation tank for inducing flocculation of ink constituents contained in waste solution coming from the one or more intaglio printing presses;   a decantation unit ( 13   a ) for separating the waste solution coming from the flocculation tank by decantation into precipitate and decanted supernatant;   a centrifugation unit for further separating the precipitate produced by the decantation unit by centrifugation into further precipitate and centrifuged supernatant;   a processing tank for pre-treating the decanted supernatant coming from the decantation unit and the centrifuged supernatant coming from the centrifugation unit for subsequent filtering; and   a filtering unit for filtering the waste solution coming from the processing tank and producing recycled solution at an output of the filtering unit, which recycled solution is recycled to produce fresh wiping solution for use by the one or more intaglio printing presses.   
     
     
         3 . The installation according to  claim 1 , further comprising a supply of a selected flocculating agent into the flocculation tank induce flocculation of the ink constituents contained in the waste solution and wherein substantially all of the selected flocculating agent is removed with the precipitate that is separated out by the centrifugation unit. 
     
     
         4 . The installation according to  claim 1 , further comprising a supply of a selected filter aid agent into the processing tank to aid filtering of the waste solution by the filtering unit. 
     
     
         5 . The installation according to  claim 4 , wherein the selected filter aid agent is Perlite. 
     
     
         6 . The installation according to  claim 1 , further comprising a collecting tank for collecting the waste solution from the one or more intaglio printing presses before flocculation in the flocculation tank. 
     
     
         7 . The installation according to  claim 1 , further comprising an overflow tank for collecting overflow of wiping solution. 
     
     
         8 . The installation according to  claim 7 , further comprising a secondary waste solution treatment system for treating the overflow of wiping solution collected in the overflow tank. 
     
     
         9 . The installation according to  claim 1 , further comprising a secondary waste solution treatment system ( 20 ) for treating a selected share of the wiping solution and removing organic residues contained therein. 
     
     
         10 . The installation according to  claim 9 , wherein the secondary waste solution treatment system is designed to take the selected share of the wiping solution from the recycled solution derived from the filtering unit. 
     
     
         11 . The installation according to  claim 8 , wherein the secondary waste solution treatment system comprises:
 a waste solution treatment tank for collecting the wiping solution; and   a secondary filtering unit for filtering the wiping solution coming from the waste solution treatment tank and producing filtered solution at an output of the secondary filtering unit.   
     
     
         12 . The installation according to  claim 11 , wherein the secondary waste solution treatment system further comprises an evaporation unit for subjecting the filtered solution derived from the secondary filtering unit to evaporation so as to recover distilled water which is either recycled to produce fresh wiping solution or drained. 
     
     
         13 . The installation according to  claim 11 , wherein the secondary filtering unit is a secondary filter press unit. 
     
     
         14 . The installation according to  claim 11 , further comprising a supply of the following processing agents into the waste solution treatment tank:
 a selected flocculating agent for inducing flocculation of ink constituents contained in the waste solution, including organic residues;   a neutralising agent for neutralising the pH of the waste solution; and   a filter aid agent to aid filtering of the waste solution by the secondary filtering unit.   
     
     
         15 . The installation according to  claim 14 , wherein the selected flocculating agent is calcium chloride (CaCl 2 ). 
     
     
         16 . The installation according to  claim 14 , wherein the neutralising agent is sulphuric acid (H 2 SO 4 ). 
     
     
         17 . The installation according to  claim 14 , wherein the filter aid agent is Perlite. 
     
     
         18 . The installation according to  claim 1 , further comprising a dosage tank for collecting the recycled solution coming from the filtering unit and dosing addition of fresh constituents to the recycled solution to produce the fresh wiping solution. 
     
     
         19 . The installation according to  claim 18 , wherein the fresh constituents include soft water, caustic soda (NaOH) and sulfonated castor oil (S.C.O.). 
     
     
         20 . The installation according to  claim 1 , further comprising means for selectively feeding the recycled solution derived from the filtering unit back to the centrifugation unit for the purpose of carrying out a cleaning operation of the centrifugation unit. 
     
     
         21 . The installation according to  claim 1 , wherein the filtering unit is a filter press unit. 
     
     
         22 . A process for recycling wiping solution of one or more intaglio printing presses, comprising the following steps:
 i. inducing flocculation of ink constituents contained in waste solution coming from the one or more intaglio printing presses to produce a flocculated solution;   ii. separating the flocculated solution by centrifugation into precipitate and centrifuged supernatant;   iii. pre-treating the centrifuged supernatant to produce a pre-treated solution for subsequent filtering; and   iv. filtering the pre-treated solution to produce a recycled solution, which recycled solution is recycled to produce fresh wiping solution for use by the one or more intaglio printing presses.   
     
     
         23 . A process for recycling wiping solution of one or more intaglio printing presses, comprising the following steps:
 i. inducing flocculation of ink constituents contained in waste solution coming from the one or more intaglio printing presses to produce a flocculated solution;   ii. separating the flocculated solution by decantation into precipitate and decanted supernatant;   iii. further separating the precipitate of the decantation by centrifugation into further precipitate and centrifuged supernatant;   iv. pre-treating the decanted supernatant and the centrifuged supernatant to produce a pre-treated solution for subsequent filtering; and   v. filtering the pre-treated solution to produce a recycled solution, which recycled solution is recycled to produce fresh wiping solution for use by the one or more intaglio printing presses.   
     
     
         24 . Use of centrifugation to process waste wiping solution of one or more intaglio printing presses, which use involves subjecting to centrifugation a flocculated solution produced as a result of flocculation of the waste wiping solution or a derivative of the flocculated solution to separate clarified solution for further processing. 
     
     
         25 . Use according to  claim 24 , wherein the clarified solution separated by centrifugation, or centrifuged supernatant, is recycled to produce fresh wiping solution. 
     
     
         26 . Use according to  claim 24 , wherein the flocculated solution is first subjected to decantation to separate the flocculated solution into precipitate and decanted supernatant and wherein only the decanted supernatant is subjected to the centrifugation. 
     
     
         27 . The installation according to  claim 2 , further comprising a supply of a selected flocculating agent into the flocculation tank to induce flocculation of the ink constituents contained in the waste solution and wherein substantially all of the selected flocculating agent is removed with the precipitate that is separated out by the centrifugation unit. 
     
     
         28 . The installation according to  claim 2 , further comprising a supply of a selected filter aid agent into the processing tank to aid filtering of the waste solution by the filtering unit. 
     
     
         29 . The installation according to  claim 28 , wherein the selected filter aid agent is Perlite. 
     
     
         30 . The installation according to  claim 2 , further comprising a collecting tank for collecting the waste solution from the one or more intaglio printing presses before flocculation in the flocculation tank. 
     
     
         31 . The installation according to  claim 2 , further comprising an overflow tank for collecting overflow of wiping solution. 
     
     
         32 . The installation according to  claim 31 , further comprising a secondary waste solution treatment system for treating the overflow of wiping solution collected in the overflow tank. 
     
     
         33 . The installation according to  claim 2 , further comprising a secondary waste solution treatment system for treating a selected share of the wiping solution and removing organic residues contained therein. 
     
     
         34 . The installation according to  claim 33 , wherein the secondary waste solution treatment system is designed to take the selected share of the wiping solution from the recycled solution derived from the filtering unit. 
     
     
         35 . The installation according to  claim 32 , wherein the secondary waste solution treatment system comprises:
 a waste solution treatment tank for collecting the wiping solution; and   a secondary filtering unit for filtering the wiping solution coming from the waste solution treatment tank and producing filtered solution at an output of the secondary filtering unit.   
     
     
         36 . The installation according to  claim 35 , wherein the secondary waste solution treatment system further comprises an evaporation unit for subjecting the filtered solution derived from the secondary filtering unit to evaporation so as to recover distilled water which is either recycled to produce fresh wiping solution or drained. 
     
     
         37 . The installation according to  claim 35 , wherein the secondary filtering unit is a secondary filter press unit. 
     
     
         38 . The installation according to  claim 35 , further comprising a supply of the following processing agents into the waste solution treatment tank:
 a selected flocculating agent for inducing flocculation of ink constituents contained in the waste solution, including organic residues;   a neutralising agent for neutralising the pH of the waste solution; and   a filter aid agent to aid filtering of the waste solution by the secondary   filtering unit.   
     
     
         39 . The installation according to  claim 38 , wherein the selected flocculating agent is calcium chloride (CaCl 2 ). 
     
     
         40 . The installation according to  claim 38 , wherein the neutralising agent is sulphuric acid (H 2 SO 4 ). 
     
     
         41 . The installation according to  claim 38 , wherein the filter aid agent is Perlite. 
     
     
         42 . The installation according to  claim 33 , wherein the secondary waste solution treatment system comprises:
 a waste solution treatment tank for collecting the wiping solution; and   a secondary filtering unit for filtering the wiping solution coming from the waste solution treatment tank and producing filtered solution at an output of the secondary filtering unit.   
     
     
         43 . The installation according to  claim 42 , wherein the secondary waste solution treatment system further comprises an evaporation unit for subjecting the filtered solution derived from the secondary filtering unit to evaporation so as to recover distilled water which is either recycled to produce fresh wiping solution or drained. 
     
     
         44 . The installation according to  claim 42 , wherein the secondary filtering unit is a secondary filter press unit. 
     
     
         45 . The installation according to  claim 42 , further comprising a supply of the following processing agents into the waste solution treatment tank:
 a selected flocculating agent for inducing flocculation of ink constituents contained in the waste solution, including organic residues;   a neutralising agent for neutralising the pH of the waste solution; and   a filter aid agent to aid filtering of the waste solution by the secondary filtering unit.   
     
     
         46 . The installation according to  claim 45 , wherein the selected flocculating agent is calcium chloride (CaCl 2 ). 
     
     
         47 . The installation according to  claim 45 , wherein the neutralising agent is sulphuric acid (H 2 SO 4 ). 
     
     
         48 . The installation according to  claim 45 , wherein the filter aid agent is Perlite. 
     
     
         49 . The installation according to  claim 9 , wherein the secondary waste solution treatment system comprises:
 a waste solution treatment tank for collecting the wiping solution; and   a secondary filtering unit for filtering the wiping solution coming from the waste solution treatment tank and producing filtered solution at an output of the secondary filtering unit.   
     
     
         50 . The installation according to  claim 49 , wherein the secondary waste solution treatment system further comprises an evaporation unit for subjecting the filtered solution derived from the secondary filtering unit to evaporation so as to recover distilled water which is either recycled to produce fresh wiping solution or drained. 
     
     
         51 . The installation according to  claim 49 , wherein the secondary filtering unit is a secondary filter press unit. 
     
     
         52 . The installation according to  claim 49 , further comprising a supply of the following processing agents into the waste solution treatment tank:
 a selected flocculating agent for inducing flocculation of ink constituents contained in the waste solution, including organic residues;   a neutralising agent for neutralising the pH of the waste solution; and   a filter aid agent to aid filtering of the waste solution by the secondary filtering unit.   
     
     
         53 . The installation according to  claim 52 , wherein the selected flocculating agent is calcium chloride (CaCl 2 ). 
     
     
         54 . The installation according to  claim 52 , wherein the neutralising agent is sulphuric acid (H 2 SO 4 ). 
     
     
         55 . The installation according to  claim 52 , wherein the filter aid agent is Perlite. 
     
     
         56 . The installation according to  claim 2 , further comprising a dosage tank for collecting the recycled solution coming from the filtering unit and dosing addition of fresh constituents to the recycled solution to produce the fresh wiping solution. 
     
     
         57 . The installation according to  claim 56 , wherein the fresh constituents include soft water, caustic soda (NaOH) and sulfonated castor oil (S.C.O.). 
     
     
         58 . The installation according to  claim 2 , further comprising means for selectively feeding the recycled solution derived from the filtering unit back to the centrifugation unit for the purpose of carrying out a cleaning operation of the centrifugation unit. 
     
     
         59 . The installation according to  claim 2 , wherein the filtering unit is a filter press unit.