Patent ID: 9638024
Date: 2017-05-02
CPC Classifications: C09K,E21B

Claim:
1. An in situ clean-up verification method for use at a well location having a well at an end of a well drilling completion process, when starting production of petroleum fluids while a completion rig is still at the well location, the verification method comprising the following steps: marking one or more separated zones along the well with one or more distinct tracers before starting the production of petroleum fluids, wherein said distinct tracers are added along with a completion system, said distinct tracers are oleophilic, said distinct tracers are optically detectable, and said distinct tracers are arranged so that they are released from each separated zone to an inflowing fluid of oil or gas; starting up the production of petroleum fluids; collecting at least one sample of a produced petroleum fluid; processing the at least one sample by a chemical cleavage reaction which introduces water soluble groups to tracer molecule structures to change said distinct tracers into non oleophilic tracers, thereby achieving at least one processed sample, wherein said non oleophilic tracers are dissolvable in a polar fluid, transferring said non oleophilic tracers from an oil in the at least one processed sample into an added, polar fluid phase, which is not miscible with an original oil phase of the at least one processed sample; and optically inspecting the added fluid phase for non oleophilic tracers to verify whether or not all of said non oleophilic tracers occur in the at least one processed sample of the produced petroleum, which thus verifies if inflow of petroleum fluids in said tracer marked separated zones takes place or not, in a start-up phase of the production.