IOR Centre Theme 2 Task 5: Tracers for SOR measurements in IW and - PowerPoint PPT Presentation

IOR Centre Theme 2 – Task 5: Tracers for SOR measurements in IW and SW application - Some recent results and future plans Tor Bjørnstad Mario Silva Thomas Brichart Alexander Krivokapic Sissel O. Viig ENI, Milano 2016 Tor Bjørnstad

PITT and SWCTT • Interwell tracer injection probes the water- contactable volume between wells. PITT measures SOR in this volume (SPE 164059) • Single well push-and-pull (SWTT) tracer application measures SOR in a volume around a well 5-10 m from wellbore. SWTT PITT ENI, Milano 2016 Tor Bjørnstad

3 Injection Production well well • Preferential flow directions • Horizontal and vertical communication between wells • Permeability strata • Sweep volumes • Large-scale heterogeneities Statified reservoir ENI, Milano 2016 Tor Bjørnstad

4 Passive and partitioning tracers… • A passive water tracer moves only with the water water • Phase-partitioning tracer distributes betweeen water and oil • At residual oil saturation water moves, oil is (close to) stagnant K = (C Tr ) o /(C Tr ) w ENI, Milano 2016 Tor Bjørnstad

5 Passive and partitioning tracer – relative speed ∝ SOR Inj. Conc. Time ENI, Milano 2016 Tor Bjørnstad

6 Relative concentration S o = (T p – T np )/[T p + T np (K – 1)] Volume (or time) ENI, Milano 2016 Tor Bjørnstad

7 Thermal degradation and sorption to substrates Heating bath,- thermally controlled Rock substrate Sealed glass (sandstones, carbonates, ampoule clays etc.) ENI, Milano 2016 Tor Bjørnstad

2,3-Dimethylpyrazine (12 weeks) ENI, Milano 2016 Tor Bjørnstad

4-Methoxybenzyl alcohol (12 weeks) ENI, Milano 2016 Tor Bjørnstad

10 Co-operation with Cornell Univ. - C-dots ENI, Milano 2016 Tor Bjørnstad

C-dots and fluorescense Due to oxygen and nitrogen functional groups on their surfaces, these carbon nanoparticles shine brightly from blue to deep red when they absorb certain wavelengths of light ENI, Milano 2016 Tor Bjørnstad

12 SWCTT principle Chemical reaction Hydrolysis reaction + + Ester Water Alcohol Acid ENI, Milano 2016 Tor Bjørnstad

13 Can a passive and a partitioning tracer be used in a SWCTT test?  See next picture frame: ENI, Milano 2016 Tor Bjørnstad

14 On backproduction……  The answer is NO! ENI, Milano 2016 Tor Bjørnstad

15 Therefore, injection of a reacting tracer is necessary  The well is shut-in for conversion of ca. 50 % of the reacting tracer into a passive water tracer ENI, Milano 2016 Tor Bjørnstad

16 Therefore, injection of a reacting tracer is necessary  On back-production, the produced water tracer starts on the same starting line as the remaining partitioning tracer and they separate on their way back. ENI, Milano 2016 Tor Bjørnstad

17 Fluorescence of Rare Earth Compounds Fluorescence spectra of selected rare earths Fluorescence colors of selected rare earths ENI, Milano 2016 Tor Bjørnstad

18 Ester-based SWCTT = Single-Well Chemical Tracer Techn. Goal: * 3 – 5 new reacting tracers for H&P measurement of SOR * We synthesize new esters, for example starting with the poly- carboxylic acid DTPA etc. DTPA ENI, Milano 2016 Tor Bjørnstad

Promising reaction OH OH O O N O N O N N OH OH + Tb 3+ Temporarily Temporarily OH OH N N cencored cencored O N N O O O OH OH OH O OH O OH N O O N OH + R-OH H 2 O + Temporarily OH N cencored N O O OH O O R ENI, Milano 2016 Tor Bjørnstad

20 Post.docs and PhD-stud. Mario Silva , Thomas Brichart , Mahmoud Ould Metidji , PhD-stud. post.doc. post.doc. ENI, Milano 2016 Tor Bjørnstad

21 New SWTT – reduction in volume and time Future timeline – before production start New timeline – after a long production period Present timeline – after a long production period ENI, Milano 2016 Tor Bjørnstad