Well testing under full field production

1. A method for well testing under full field production, wherein well flow from multiple wells ( 200 a - 200 d ) is run through a production system during full field production, the production system comprising a production slug suppression and gas removal unit ( 100 ) and a separator system ( 10 ) comprising multiple interconnected inclined tubular separators ( 11 a - 11 e ) for separating gas, oil and water from the well flow, comprising the steps of:

(a) isolating well flow from one of the multiple wells ( 200 a - 200 d ) to define an isolated well and isolating at least one of the inclined tubular separators ( 11 a - 11 e ) from the multiple interconnected inclined tubular separators ( 11 a - 11 e ) and dedicating the at least one isolated inclined tubular separator ( 11 a - 11 e ) for testing,

(b) running the well flow from the isolated well ( 200 a - 200 d ) through a dedicated test slug suppression and gas removal unit ( 310 ) and the at least one isolated and dedicated inclined tubular separator ( 11 a - 11 e ) to initiate a test period,

(c) running well flow from non-isolated wells ( 200 a - 200 d ) through the production slug suppression and gas removal unit ( 100 ) and non-isolated inclined tubular separators ( 11 a - 11 e ),

(d) measuring volumes of gas, oil and water produced for the isolated well ( 220 a - 200 d ),

(e) adding the respective gas, oil and water produced for the isolated well ( 220 a - 200 d ) from the dedicated test slug suppression and gas removal unit ( 310 ) and the at least one isolated and dedicated inclined tubular separator ( 11 a - 11 e ) to the respective gas, oil and water produced for the non-isolated wells ( 200 a - 200 d ) from the production slug suppression and gas removal unit ( 100 ) and the non-isolated inclined tubular separators ( 11 a - 11 e ), and

(f) removing the isolation of the isolated well ( 200 a - 200 d ) and at least one isolated and dedicated inclined tubular separator ( 11 a - 11 e ) to end the test period.

2. The method according to claim 1 , comprising repeating steps (a)-(f) for different wells ( 200 a - 200 d ).

3. The method according to claim 2 , comprising running the well flow from the isolated well ( 200 a - 200 d ) through at least one dedicated test sand trap ( 340 ) and measuring content of sand in the well flow.

4. The method according to claim 2 , comprising allowing a stabilizing period after step (b) and prior to step (d) of measuring volumes of gas, oil and water produced for the isolated well ( 220 a - 200 d ).

5. The method according to claim 1 , comprising running the well flow from the isolated well ( 200 a - 200 d ) through at least one dedicated test sand trap ( 340 ) and measuring content of sand in the well flow.

6. The method according to claim 5 , comprising allowing a stabilizing period after step (b) and prior to step (d) of measuring volumes of gas, oil and water produced for the isolated well ( 220 a - 200 d ).

7. The method according to claim 1 , comprising allowing a stabilizing period after step (b) and prior to step (d) of measuring volumes of gas, oil and water produced for the isolated well ( 220 a - 200 d ).

8. A system for well testing under full field production, wherein well flow from multiple wells ( 200 a - d ) is run through a production system during full field production, the production system comprising a production slug suppression and gas removal unit ( 100 ) and a separator system ( 10 ) comprising multiple interconnected inclined tubular separators ( 11 a - 11 e ) for separating gas, oil and water from the well flow, comprising:

(a) controllable units (PV 1 -PV 4 , TV 1 -TV 4 ) for isolating well flow from one of the multiple wells ( 200 a - 200 d ) from well flow of the non-isolated wells ( 200 a - 200 d ),

(b) a dedicated test slug suppression and gas removal unit ( 310 ) for separation of gas from the well flow from the isolated well ( 200 a - 200 d ),

(c) controllable units (HV 1 -HV 2 , HV 4 -HV 5 , WV 4 -WV 5 , LCVT, OV 4 -OV 5 ) for isolating at least one of the inclined tubular separators ( 11 a - 11 e ) from the multiple interconnected inclined tubular separators ( 11 a - 11 e ) and dedicating the at least one isolated inclined tubular separator ( 11 a - 11 e ) for separation of the well flow from the isolated well ( 200 a - 200 d ), and

(d) units (GM, OM, WM) for measuring gas, oil and water volumes (m 3 /h) produced for the isolated well ( 220 a - d ),

wherein the units for isolating well flow (PV 1 -PV 4 , TV 1 - 4 ) and units for isolating at least one of the inclined tubular separators (HV 1 -HV 2 , HV 4 -HV 5 , WV 4 -WV 5 , LCVT, OV 4 -OV 5 ) collectively allow the well flow from the isolated well ( 200 a - 200 d ) to be run through the dedicated test slug suppression and gas removal unit ( 310 ) and the at least one isolated and dedicated inclined tubular separator ( 11 a - 11 e ) for a test period while well flow from the non-isolated wells ( 200 a - 200 d ) is run through the production slug suppression and gas removal unit ( 100 ) and multiple interconnected inclined tubular separators ( 11 a - 11 e ),

and comprising outlets, lines or both ( 311 , 320 , 330 ) for adding the respective produced gas, oil and water for the separated well ( 220 a - 200 d ) from the dedicated test slug suppression and gas removal unit ( 310 ) and the at least one isolated and dedicated inclined tubular separator ( 11 a - 11 e ) to the respective produced gas, oil and water for the non-isolated wells ( 200 a - 200 d ) from the production slug suppression and gas removal unit ( 100 ) and the multiple interconnected inclined tubular separators ( 11 a - 11 e ).

9. The system according to claim 8 , comprising at least one dedicated test sand trap ( 340 ) and units (SV 4 -SV 5 ) for running the well flow from the isolated well ( 200 a - 200 d ) through the at least one dedicated test sand trap ( 340 ).

10. The system according to claim 9 , comprising a unit (MS) for measuring sand content in the at least one dedicated test sand trap ( 340 ).