Underwater sediment management

Abstract

The present invention relates to underwater sediment management. In particular, we will describe dredging and scouring apparatus for removing sand, silt, clay and like materials from sea or river beds. There is described an apparatus comprising a body ( 10 ) having a bottom face ( 13, 14 ) and comprising an outlet flow path ( 28 ) in which is mounted propeller thrust means ( 29 ) to direct, in use, a swirling jet of water downwards towards an area of sea or river bed or the like, orientation means ( 48, 49 ) to connect said apparatus, in use, to a support means to orientate said apparatus with respect to the sea or river bed, and at least one inlet flow path ( 30 ) through which water is supplied, in use, to the propeller thrust means ( 29 ); characterised in that the inlet ( 30 ) and outlet ( 28 ) flow paths are provided with respective openings in the bottom face ( 13, 14 ) or the body. In the preferred embodiments, the inlet and outlet flow paths are parallel, but of opposite directions.

1 . An apparatus comprising a body having a bottom face and comprising an outlet flow path in which is mounted thrust means to direct, in use, a wash of water downwards towards an area of sea or river bed or the like, orientation means to connect said apparatus, in use, to a support means to orientate said apparatus with respect to the sea or river bed, and at least one inlet flow path through which water is supplied, in use, to the thrust means; characterised in that the inlet flow path and outlet flow path are provided with respective openings in the bottom face of the body; in that at least a portion of the outlet flow path comprises a duct; and in that the thrust means comprises a propeller mounted within the duct.  
     
     
         2 . An apparatus as claimed in  claim 1  wherein the inlet and outlet flow paths are parallel, but of opposite directions.  
     
     
         3 . An apparatus as claimed in  claim 1  wherein the duct is formed with an outlet in the undersurface of a central section of the body.  
     
     
         4 . An apparatus as claimed in  claim 1  wherein an adjustable flow regulator is provided adjacent the inlet of the inlet flow path.  
     
     
         5 . A apparatus as claimed in  claim 4  wherein the flow regulator comprises a louvre assembly.  
     
     
         6 . An apparatus as claimed in  claim 1  wherein the body is in the form of a wing having an angled face at at least one of the leading and trailing edges thereof.