Vented Gas Drilling Fluid Catch Apparatus

Abstract

The present invention is directed to a catch tank for drilling operations. The catch tank is located between a mud-gas separator and a flare. The catch tank has an inlet port with a closed end baffle which allows a drilling fluid-gas mixture to be separated and gas to proceed to the flare without entrained drilling fluid.

What is claimed is: 
     
         1 . An apparatus for capturing drilling fluid from a mud-gas separator located downstream from a drilling rig comprising:
 a gas line in communication with the mud-gas separator   a flare located downstream from the mud-gas separator; and   a catch tank comprising an inlet port located on the gas line between the mud-gas separator and the flare, wherein the catch tank comprises:
 a director for directing mud from the inlet port downward; and 
 a gas line outlet in communication with the flare. 
   
     
     
         2 . The apparatus of  claim 1  wherein the director comprises a baffle. 
     
     
         3 . The apparatus of  claim 2  wherein the baffle comprises a closed-end baffle. 
     
     
         4 . The apparatus of  claim 1  wherein the director comprises an interior wall of the catch tank. 
     
     
         5 . The apparatus of  claim 1  further comprising a panic line communication with the drilling rig and the catch tank, wherein the panic line is directed toward the director. 
     
     
         6 . The apparatus of  claim 5  further comprising an alarm for detecting fluid in the panic line. 
     
     
         7 . The apparatus of  claim 1  further comprising a fluid line outlet for removal of mud from the catch tank. 
     
     
         8 . The apparatus of  claim 1  wherein the inlet port is located on a bottom side of the catch tank. 
     
     
         9 . The apparatus of  claim 1  wherein the inlet port is located proximate a top side of the catch tank. 
     
     
         10 . The apparatus of  claim 1  wherein the inlet port is within the catch tank such that a portion of the gas line is within the catch tank. 
     
     
         11 . A method for preventing the escape of drilling fluid through a flare line comprising:
 receiving a gas stream from a. mud-gas separator at an inlet port of a catch tank;   directing any mud within the gas stream downward upon entering the catch tank; and   flaring the mud-free gas.   
     
     
         12 . The method of  claim 11  wherein the mud is directed downward by a closed-end baffle. 
     
     
         13 . The method of  claim 11  wherein the mud is directed downward by an inside wall of the catch tank. 
     
     
         14 . The method of  claim 11  further comprising removing drilling mud from the catch tank. 
     
     
         15 . The method of  claim 11  further comprising receiving a gas stream from a drilling rig at a panic line. 
     
     
         16 . The method of  claim 15  further comprising activating an alarm when a gas stream is received at the panic line. 
     
     
         17 . The method of  claim 11  wherein the mud-gas separator is downstream of a drilling rig. 
     
     
         18 . The method of  claim 17  wherein the catch tank is removable from a gas line, wherein the gas line is between the mud-gas separator and the flare. 
     
     
         19 . The method of  claim 18  wherein the mud is directed downward by an inside wall of the catch tank.