Remote gas monitoring apparatus for seabed drilling

摘要

Gas monitoring apparatus associated with a remotely operated seabed system, the apparatus including a detector which is adapted so as to enable detection and/or measurement in real time the interception of shallow gas in a bore hole. In one form the gas monitoring apparatus is suitable for use with a drilling rig for drilling into a sea bed, the drilling rig including a drill string. The gas monitoring apparatus includes a housing with a collecting chamber therein for receiving drilling fluid returns which result from a drilling operation. The apparatus further includes a discharge conduit for discharging the drilling fluid returns from the collecting chamber, the collecting chamber and discharge conduit being configured so that the drilling fluid is discharged in a stratified flow which includes a predominantly dissolved gas containing phase, and if present a free gaseous phase. A gas sensor is associated with the discharge conduit and positioned so as to sense any gas in the predominantly dissolved gas containing phase and transmit the measured gas concentration signal in real-time to a surface operating station. In another form the apparatus includes a gas monitoring probe assembly suitable for use with a drilling rig for drilling into a sea bed, the gas monitoring probe assembly including a housing attachable to one end of a drill string of the rig and which includes a gas sensor having a gas sensor face within the housing.

主权项

1. Underwater gas monitoring apparatus associated with remotely operated seabed survey equipment, the apparatus including a detector which includes a collector for continuously collecting drilling fluid returns and contacting the drilling fluid returns with an underwater gas sensor so as to enable detection and measurement in real time the interception of gas in a bore hole, the collector including a collecting chamber for receiving the drilling fluid returns which result from a drilling operation, the drilling fluid returns including fluid containing solids from the drilling operation and, if present, dissolved gas, the apparatus further including a discharge conduit for discharging the drilling fluid returns from the collecting chamber, the collecting chamber and the discharge conduit being configured so that the drilling fluid returns is discharged in a stratified flow which includes a predominantly dissolved gas containing phase, the underwater gas sensor associated with the discharge conduit and positioned so as to sense any gas in the predominantly dissolved gas containing phase.