Dual stage flow back recovery system

Abstract

A flow back recovery system for wells includes a plurality of pressure vessels with baffles and outlets for separating the various components of the flow back fluid. A diffuser is positioned between the well head and the first pressure vessel. The diffuser includes an interior diffuser pipe having a plurality of baffles and outlets. The diffuser pipe may be easily replaced in the field should it wear out due to the abrasive nature of the flow back fluid.

I claim: 
     
         1 . A dual stage flow back recovery system comprising:
 a first pressure vessel having a diffuser at a fluid inlet;   a first baffle extending from a lower wall of the pressure vessel;   one or more dump valves in the lower wall of the pressure vessel for removing solid material from the pressure vessel;   a second pressure vessel having a second baffle extending from a lower wall of the second pressure vessel, the baffle serving to separate a water chamber from an oil chamber;   a conduit extending between the first and second pressure vessels at a lower portion thereof for conveying liquids from the first pressure vessel to the second pressure vessel;   a second conduit for gas extending between the first and second pressure vessels at an upper portion thereof for conveying gas from the first pressure vessel to the second pressure vessel;   a gas outlet conduit in the upper portion of the second pressure vessel for directing gas either to a sales gas line or a flare gas line;   one or more dump valves in the bottom of the second pressure vessel for discharging solid material from the second pressure vessel;   one or more mechanical dump valves in the bottom of the water chamber for dumping liquid water to a frac tank;   a mechanical dump valve in the oil chamber for directing oil to a remote location; and   a closed top tank for storing liquid separated out in the second pressure vessel.   
     
     
         2 . The system of  claim 1  wherein the components of the system are mounted on a trailer and are pre-assembled and tested for compliance with regulatory requirements. 
     
     
         3 . The system of  claim 1  wherein the closed top tank includes a vent and a flapper valve. 
     
     
         4 . The system of  claim 1  wherein the first and second pressure vessels and the closed top tank include pressure relief valves. 
     
     
         5 . The system of  claim 1  wherein the first pressure vessel includes an inclined baffle positioned to intercept the fluid as it flows into the pressure vessel from the diffuser. 
     
     
         6 . The system of  claim 5  further including one or more apertured baffle plates extending from a top portion of the first pressure vessel. 
     
     
         7 . A diffuser for a flow back recovery system comprising:
 a housing having a fluid outlet at one end and a closed second end with an opening for a diffuser pipe;   a diffuser pipe positioned within the housing and including a plurality of inwardly extending baffles; and   a plurality of outlets in the diffuser pipe;   
     
     
         8 . The diffuser as claimed in  claim 7  wherein the baffles are portions of the diffuser pipe formed by cutting through the pipe and bending the portions into the pipe. 
     
     
         9 . The diffuser as claimed in  claim 8  wherein the outlets are formed by bending the baffles inwardly. 
     
     
         10 . The diffuser as claimed in  claim 7  further including a sleeve positioned within the housing and in contact therewith. 
     
     
         11 . The diffuser as claimed in  claim 7  wherein the housing and the sleeve are cylindrical in shape. 
     
     
         12 . The diffuser as claimed in  claim 7  wherein the diffuser pipe is cylindrical in shape.