Apparatus for collecting samples of drill cuttings and method of use

Abstract

An apparatus and a method for surface logging include a vacuum assisted transfer of drill cuttings from a shale shaker to sample jars. The cuttings samples are used for measurements to characterize formations in which a wellbore is drilled. The apparatus has an adjustable suction line that can be used to control moisture on the surface of the drill cuttings fragments. The method includes an automated sample collection and a high throughput sample treatment (e.g., washing or/and a controllable drying) to increase value of measurements.

What is claimed is: 
     
         1 . An apparatus for collecting samples of drill cuttings using vacuum assisted cuttings transfer from a shale shaker to a sample jar, the apparatus comprising:
 a movable inlet port;   a suction line to transfer cuttings from the inlet port to a discharge chamber;   a set of actuators to control position of the inlet port and the sample jar; and   an electronics unit.   
     
     
         2 . The apparatus of  claim 1 , further comprising a vacuum control unit, the vacuum control unit including an air operated (non-electric) vacuum pump. 
     
     
         3 . The apparatus of  claim 1 , wherein the set of actuators includes pneumatic actuators. 
     
     
         4 . The apparatus of  claim 1 , wherein the electronics unit is placed in an explosion-proof enclosure, the enclosure having a hermetic seal and a pressured nitrogen to avoid accidental penetration of flammable vapors inside the enclosure. 
     
     
         5 . The apparatus of  claim 1  further comprises a jar cassette for empty jars and a collection tray, the tray collecting the jars filled with the drill cuttings. 
     
     
         6 . The apparatus of  claim 1 , wherein the jar has a sample identification code. 
     
     
         7 . The apparatus of  claim 1  further comprises an at least one machine vision device. 
     
     
         8 . The apparatus of  claim 7 , wherein the at least one machine vision device is used for at least one of (i) monitoring the amount of the drill cuttings to be collected by the movable inlet and (ii) providing the cuttings description. 
     
     
         9 . The apparatus of  claim 1  further comprises an automated sample treatment unit. 
     
     
         10 . The apparatus of  claim 9 , wherein the sample treatment unit comprises means for a simultaneous treatment of a plurality of the drill cuttings samples, the treatment including at least one of (i) washing the sample and (ii) at least partly drying the sample. 
     
     
         11 . The apparatus of  claim 1  further includes sensors to monitor an at least one of (i) a pressure in the suction line, (ii) a pressure in a discharge chamber, (iii) a pressure in the vacuum control unit and (iv) the nitrogen pressure. 
     
     
         12 . The apparatus of  claim 1 , wherein the suction line is adjustable to control surface moisture of the drill cuttings. 
     
     
         13 . A method for collecting samples of drill cuttings, the method comprising:
 transferring the drill cuttings from a shaker using a vacuum assisted flow via a suction line;   collecting the drill cuttings samples in sample jars; and   using the samples for measurements to characterize formations in which a wellbore is drilled.   
     
     
         14 . The method of  claim 13  further comprises a step of at least partly removing residual fluids from the drill cuttings surface, the residual fluids controlled by adjusting geometry and/or regimes of the suction line; 
     
     
         15 . The method of  claim 13 , wherein the step of transferring includes a quantitative description of the cuttings. 
     
     
         16 . The method of  claim 13 , wherein the measurements comprises bulk sensitive measurements at a well site, the bulk sensitive measurements including at least one of (i) natural gamma spectroscopy and (ii) nuclear magnetic resonance relaxometry. 
     
     
         17 . The method of  claim 13  further comprises a step of placing the sample tray into an automated sample preparation unit to perform at least one of (i) automated washing the cuttings, (ii) controllable drying the cuttings and (iii) filling the space between the cuttings fragments in the sample jar with a fluid having known properties. 
     
     
         18 . A method of surface logging using measurements on drill cuttings, the method comprising:
 collecting a plurality of drill cuttings samples in sample jars;   treating the plurality of drill cuttings samples before the measurements, the treating conducted automatically on the plurality of the drill cuttings samples; and   using the measurements to evaluate formations.   
     
     
         19 . The method of  claim 18 , wherein the treating includes an at least one of (i) automated washing the cuttings, (ii) controllable drying the cuttings and (iii) filling the space between the cuttings fragments in the jar with a fluid having known properties. 
     
     
         20 . The method of  claim 18 , wherein the measurements comprise bulk sensitive measurements including an at least one of (i) natural gamma spectroscopy and (ii) nuclear magnetic resonance relaxometry.