Nets for bodies of water

Abstract

A net ( 10 ) for a body of water ( 12 ) that serves to collect flat objects ( 11 ), which are made of foamed plastic and which are saturated with contamination substances, is provided with a catching net part ( 13 ), which can be vertically placed in the body of water ( 12 ) by means of a longitudinally extending sink line ( 18 ) and of a longitudinally extending float line ( 21, 22 ). The aim of the invention is to be able to pull a net of the aforementioned type through the water while tensioned, whereby an upper area of the net always remains above the water surface even in rough water. To this end, the invention provides that the catching net part ( 13 ) is widened by a flexible net part ( 14 ) that, in the area of its free longitudinal edge, is fitted with a longitudinally extending sink line ( 32 ) and is fitted with at least one main float line ( 33 ) between said longitudinal edge and the upper float line ( 21, 22 ) of the catching net part ( 13 ).

1 . Net ( 10 ,  110 ) for waters ( 12 ,  112 ) to intercept, collect and/or recover flat products ( 11 ,  111 ), particularly of open-cell expanded plastic soaked with polluting substances, on or from the surface of water ( 12 ,  112 ), with a fixed net part ( 13 ,  113 ) which an be arranged in water ( 12 ,  112 ) mainly in upright position by means of a first longitudinal lower ballast unit ( 18 ,  118 ) and a first longitudinal upper float unit ( 21 ,  121 ), characterized by the fixed net part ( 13 ,  113 ) being widened by a flexible net part ( 14 ,  114 ) which, in the area of its longitudinal edge distant from the fixed net part ( 13 ,  113 ), is equipped with a second longitudinal ballast unit ( 32 ,  132 ) and, between the latter and the first upper float unit ( 21 ,  121 ) for the fixed net part ( 13 ,  113 ), with at least one second longitudinal main float unit ( 33 ,  133 ).  
     
     
         2 . Net according to  claim 1 , characterized by the main float line ( 33 ) being at a shorter distance from the ballast line ( 32 ) of the flexible net part ( 14 ) than from the float line ( 21 ,  22 ) of the fixed net part ( 13 ).  
     
     
         3 . Net according to  claim 1 , characterized by the distance between the main float line ( 33 ) and the ballast line ( 32 ) of the flexible net part ( 14 ) being considerably shorter than the distance between the float line ( 21 ,  22 ) and the ballast line ( 18 ) of the fixed net part ( 13 ).  
     
     
         4 . Net according to  claim 1 , characterized by one or more ancillary float lines ( 36 ) being provided between the float line of the grid net part ( 14 ) and the main float line ( 33 ) of the flexible net part ( 14 ).  
     
     
         5 . Net according to  claim 4 , characterized by the ancillary float lines ( 36 ) being evenly spaced between the float line ( 21 ,  22 ) of the fixed net part ( 13 ) and the main float line ( 33 ) of the flexible net part ( 14 ).  
     
     
         6 . Net according to  claim 1 , characterized by at least a part of the flexible net part ( 14 ) being composed of two or more superimposed net layers ( 26 - 28 ).  
     
     
         7 . Net according to  claim 6 , characterized by the net layers ( 27 ,  28 ) being superimposed in meanders.  
     
     
         8 . Net according to  claim 1 , characterized by the flexible net part ( 14 ) being bending-elastic along its width.  
     
     
         9 . Net ( 110 ) according to  claim 1 , characterized by, along the width of the net ( 110 ), a second fixed net part ( 120 ) being connected to the longitudinal edge, distant from the first fixed net part ( 113 ), of the net part ( 114 ) which is flexible along its width.  
     
     
         10 . Net according to  claim 9 , characterized by the second fixed net part ( 120 ) being connected by its free longitudinal edge ( 124 ) to the first fixed net part ( 113 ).  
     
     
         11 . Net according to  claim 10 , characterized by the second fixed net part ( 120 ) having a width corresponding to the width of the first fixed net part ( 113 ) and the free longitudinal edges ( 117 ,  124 ) of the two fixed net parts ( 113 ,  120 ) being connected to each other.  
     
     
         12 . Net according to  claim 11 , characterized by the first lower ballast unit ( 118 ) being common to the two fixed net parts ( 113 ,  120 ) and by a pull line ( 125 ) being provided in this connection area of the two fixed net parts ( 113 ,  120 ).  
     
     
         13 . Net according to  claim 9 , characterized by the width of the flexible net part ( 114 ) being equal to or somewhat less than the sum of the individual widths of the two fixed net parts ( 113 ,  120 ).  
     
     
         14 . Net according to  claim 9 , characterized by the flexible net part ( 114 ) being manufactured in a slack net design connected to nonmetallic flexible bars ( 150 ) over its width.  
     
     
         15 . Net according to  claim 14 , characterized by the flexible bars ( 150 ) being threaded through the net design.  
     
     
         16 . Net according to  claim 14 , characterized by the flexible bars ( 150 ) being evenly spaced over the length of the flexible net part ( 114 ).  
     
     
         17 . Net according to  claim 9 , characterized by the float units ( 121 ,  133 ) being composed of extended strips ( 151 ) preferably of closed-cell expanded plastic.  
     
     
         18 . Net according to  claim 17 , characterized by the float strips ( 151 ) being threaded through the net design.  
     
     
         19 . Net according to  claim 17 , characterized by several float strips ( 151 ) being provided in parallel side by side in each float unit ( 121 ,  133 ).  
     
     
         20 . Net according to  claim 9 , characterized by the first fixed net part ( 113 ), the flexible net part ( 114 ), and the second fixed net part ( 120 ) being manufactured as an integral unit.  
     
     
         21 . Net according to  claim 1 , characterized by its capability of being coiled in the flat state.  
     
     
         22 . Net according to  claim 1 , characterized by its capability of being placed on the water ( 12 ,  112 ) in the flat state.  
     
     
         23 . Net according to  claim 1 , characterized by a longitudinal pull rope ( 23 ,  125 ) being provided between fixed net part ( 13 ,  113 ) and flexible net part ( 14 ,  114 ).  
     
     
         24 . Net according to  claim 1 , characterized by an extraction hollow section ( 44 ,  144 ) being provided between two nets ( 10 ,  110 ) in the connecting area of fixed net part ( 13 ,  113 ) and flexible net part ( 14 ,  114 ) and above and/or below this area.  
     
     
         25 . Process to remove pollutant layers such as oily layers, e.g. oil patches, thin layers of oil or of liquid plastic, e.g. styrene, from surfaces of water using flat products or open-cell expanded plastic such as PP or PU or PE open-cell foam, the flat products being placed on the water surface and, when soaked with polluting substances, recovered by means of one or more nets according to  claim 1 , characterized by the net being uncoiled from a drum in the flat state and placed on the water surface, with two or more net sections being connected to each other by means of an extraction hollow section, and the free ends of the external net sections being connected to buoys or an anchor and/or ships by means of pull ropes.  
     
     
         26 . Process according to  claim 25 , characterized by one or two ships circling around the polluted zone on the water surface.  
     
     
         27 . Process according to  claim 25 , characterized by the net sections being placed off the coast in a zigzag manner.