Method and relative system for the extraction of the gases contained in drilling mud

Abstract

Method and relative system for the extraction of the gases contained in drilling mud, preferably, in a managed pressure drilling system, comprising the phases of: extraction of the drilling mud from the return piping, preferably, under pressure, sending of said mud to a degasser and extraction of the gases dissolved in the drilling mud by means of said degasser; characterised in that monitoring is provided of the quantity of drilling mud extracted from said piping, and a regulation of the quantity of mud to be extracted from said piping, said regulation being performed on the basis of said monitoring in such a way that the volumetric flow rate of mud which is sent to said degasser is constant.

What is claimed is: 
     
         1 . A method for the extraction of gases contained in drilling mud, preferably, but not exclusively, in a managed pressure drilling system, comprising the steps of:
 extracting the drilling mud by return piping, wherein said mud circulates after rising to the surface from a drilling well;   sending of said mud to a degasser;   extracting gases from said drilling mud by means of said degasser;   wherein said method provides for monitoring of a quantity of drilling mud extracted by the return piping, and a regulation of the quantity of mud to be extracted by said return piping, said regulation being performed on the basis of said monitoring in such a way that the volumetric flow rate of mud which is sent to said degasser is constant.   
     
     
         2 . The method of  claim 1 , wherein said monitoring of the quantity of drilling mud extracted by the return piping is performed by monitoring means placed downstream of a point of extraction of the mud by said return piping and upstream of said degasser. 
     
     
         3 . The method according to  claim 2 , wherein said regulation of the quantity of mud to be extracted by said return piping is performed by regulation means placed downstream of the point of extraction of the mud by said return piping and upstream of said monitoring means. 
     
     
         4 . The method according to  claim 3 , wherein said regulation means are suitable for receiving electronic signals coming from said monitoring means, the quantity of mud extracted by said return piping being dependent on said signals coming from said monitoring means. 
     
     
         5 . The method according to  claim 4 , wherein said monitoring means comprise a can suitable for collecting the drilling mud extracted by the return piping, the mud collected in said can being subsequently sent to said degasser. 
     
     
         6 . The method according to  claim 5 , wherein said monitoring means comprise a level sensor suitable for measuring the level reached by the drilling mud inside said can. 
     
     
         7 . The method according to  claim 6 , wherein said regulation means comprise an automatic valve with proportional opening suitable for receiving in input the drilling mud extracted by the return piping and to send in output to said can a quantity of mud proportional to the signal sent by said level sensor to said valve. 
     
     
         8 . The method according to  claim 7 , wherein said extraction of the mud by the return piping takes place by means of a self-cleaning filtration probe. 
     
     
         9 . The method according to  claim 8 , wherein said volumetric flow rate of mud which from said can arrives at said degasser is equal to approximately 3 litres per minute. 
     
     
         10 . The method according to  claim 9 , wherein said level sensor is a microwave level sensor. 
     
     
         11 . Method according to  claim 9 , wherein the mud is brought to a temperature between 50° C. and 70° C. before said extraction of the gases from said drilling mud by means of said degasser. 
     
     
         12 . The method according to  claim 10 , wherein the mud is brought to a temperature between 50° C. and 70° C. before said extraction of the gases from said drilling mud by means of said degasser. 
     
     
         13 . The method according to  claim 1 , wherein said regulation of the quantity of mud to be extracted by said return piping is performed by regulation means placed downstream of the point of extraction of the mud by said return piping and upstream of said monitoring means. 
     
     
         14 . The method according to  claim 1 , wherein said regulation means are suitable for receiving electronic signals coming from said monitoring means, the quantity of mud extracted by said return piping being dependent on said signals coming from said monitoring means. 
     
     
         15 . The method according to  claim 1 , wherein said monitoring means comprise a can suitable for collecting the drilling mud extracted by the return piping, the mud collected in said can being subsequently sent to said degasser. 
     
     
         16 . The method according to  claim 1 , wherein said monitoring means comprise a level sensor suitable for measuring the level reached by the drilling mud inside said can. 
     
     
         17 . The method according to  claim 1 , wherein said regulation means comprise an automatic valve with proportional opening suitable for receiving in input the drilling mud extracted by the return piping and to send in output to said can a quantity of mud proportional to the signal sent by said level sensor to said valve. 
     
     
         18 . The method according to  claim 1 , wherein said extraction of the mud by the return piping takes place by means of a self-cleaning filtration probe. 
     
     
         19 . The method according to  claim 1 , wherein said volumetric flow rate of mud which from said can arrives at said degasser is equal to approximately 3 litres per minute. 
     
     
         20 . The method according to  claim 1 , wherein said level sensor is a microwave level sensor.