Method and Apparatus for Washing Rock Samples

Abstract

A methods and associated apparatus for washing rock samples, which is particularly suited to the washing and preparation of rock samples obtained from oil and gas wells. In one embodiment there is provided a method of washing rock samples involving a plurality of discrete rock samples; providing a plurality of sequentially arranged discrete washers each of which is spaced from a respective washing position and configured to direct a washing flow of water towards said washing position; and automatically conveying said samples relative to said washers so that each sample moves in succession through said washing positions for sequential washing by each said washer.

1 . A method of washing rock samples for subsequent studying and derivation of geological information from the rock samples, the method comprising the steps of:
 placing a plurality of discrete rock samples, each having derivable geological information on a conveyor;   automatically conveying each of said rock samples in a step-wise manner to a plurality of sequential washing stations, said washing stations provided by a plurality of sequentially arranged equi-spaced discrete washers, each washer providing a respective washing station by directing a washing flow of water onto said respective washing stations;   stopping each rock sample at each washing station for a predetermined equal washing period during which each sample is washed while stationary by said respective washing flow of water, wherein each sample is moved by an index distance between successive said washing periods equal to the distance by which said washers are equi-spaced apart;   automatically conveying, subsequent to said being washed, each rock sample in a step-wise manner to a plurality of sequential drying stations, said drying stations provided by a plurality of sequentially arranged equi-spaced discrete dryers, each dryer providing a respective drying station by directing heat onto said respective drying stations; and   stopping each rock sample at each drying station for a predetermined equal drying period during which each sample is dried while stationary by said respective direction of heat, wherein each sample is moved by said index distance between successive said drying periods equal to the distance by which said dryers are equi-spaced apart.   
     
     
         2 . The method according to  claim 1 , comprising supplying of fresh water to at least one of said washers. 
     
     
         3 . The method according to  claim 1 , comprising a step of collecting water used to wash said samples in each said washing station and recirculating the water for supply to at least one of said washers. 
     
     
         4 . The method according to  claim 3 , wherein said step of automatically conveying the samples to said washing stations comprises moving each said sample through the washing station associated with the at least one washer supplied with recirculated water before the washing station associated with the at least one washer supplied with fresh water. 
     
     
         5 . The method according to  claim 3  wherein a plurality of said washers are supplied with recirculated water, and a single washer is supplied with fresh water. 
     
     
         6 . The method according to  claim 3 , further comprising a step of filtering said recirculated water prior to its supply to the at least one washer. 
     
     
         7 . The method according to  claim 3 , further comprising a step of passing said recirculated water over a weir prior to its supply to the at least one washer. 
     
     
         8 . The method according to  claim 1 , further comprising a step of RF tagging each sample. 
     
     
         9 . The method according to  claim 1 , further comprising a step of placing each said sample in a respective receptacle prior to said conveying to said drying stations, wherein the respective receptacle permits water remaining on the sample to drain. 
     
     
         10 . The method according to  claim 9 , wherein each said receptacle takes the form of a sieve. 
     
     
         11 . The method according to  claim 1 , wherein each said dryer comprises an infrared lamp. 
     
     
         12 . The method according to  claim 1 , further comprising a step of automatically agitating each sample as it is dried. 
     
     
         13 . The method according to  claim 1 , further comprising a step of photographing each sample after said drying. 
     
     
         14 . The method according to  claim 1 , further comprising a step of weighing each sample after said drying. 
     
     
         15 . The method according to  claim 1 , further comprising a step of labelling each sample after said drying. 
     
     
         16 . The method according to  claim 1 , wherein the rock samples are small rock fragments from a drilling process, the small rock fragments obtained as ditch cuttings and arriving as dirty fragments of rock covered in drilling mud. 
     
     
         17 . The method according to  claim 1 , further comprising a step of labelling the samples with the identity and location of the rock samples for the subsequent studying and derivation of geological information from the rock samples. 
     
     
         18 . The method of  claim 1 , wherein the placing of the plurality of discrete rock samples on a conveyor further comprises sequentially placing the plurality of discrete rock samples on the conveyor.