INTRODUCTION:

Together with Great Technology Co. Ltd, we has conduct 2 (two) years research to determine the right type of chemical to increase well productivity by taking core samples represents the formation in SES Area.

The following chemical types are supplied:

A.  High Water Cut Wells Solution (Completion Fluid)

     The addition of these chemicals aims to change the physical properties of the reservoir fluid,

     which is reducing the interface tension between water and oil. Hence, the reduction in

     interface tension yields oil mobility increase in the reservoir so that the rate of

     production will be increased.

      Basic Composition:

      Completion fluid used is filtered sea water + KCL + scale inhibitor + clay stabilizer +

      oxygen scavenger this to avoid formation damage.

 B.  Low Flow Infill Well Solution (Unplugging Fluid)

      This chemicals application is repairing damage wellbore by recovering permeability

      value of affected formations so that it return to its initial condition, which ultimately

      results in increased well productivity. This type of chemical does not cause corrosion

      in production equipment because the average pH in chemical is 4 - 5 (Weak Acid).

      This chemical type has 3 (three) injection stages:

      1.    Pre Fluid 

             Function : Demulsification : dissolve Ca²⁺?Mg²⁺ ion solid particle near wellbore,

             Degradation and dispersion of clay minerals mud cake.

             Type: Unplugging agent?Density: 1.03    PH Value 2—3

      2.    The Main Fluid

             Function : Dissolution and chelation of aluminosilicate minerals and form a

             membrane on clay mineral surface?prevent causing secondary damage.

             Type: GTS-F non-acid plug removal?Density: 1.04– 1.07   PH Value 3—4

      3.    Flush Fluid

             Function : Well circulation flushing, carried the solid phase pollutant or

             non corrosion particles out Type?Low friction active water or work filed

             liquid : density: 1.03

SUCCESS STORY:

CNOOC SES Ltd awarded contract for this Chemical use in 2016. Project implementation involved

10 wells chemical completion and 1 well unplugging in the North and South CNOOC SES Ltd work

area with significant results 7 out of 10 Well. The injection completion fluid was declared successful.

in increasing the production of CNOOC SES Ltd. Therefore, by knowing the characteristics of the

reservoir, we can make the right formula to maximize the radius of the injection area.

Chemical composition used at CNOOC SES Ltd. following:

A. Completion fluid:

    2% GLT-6#High Salinity Crude Oil Water Soluble Viscosity Reducer + 1% GTA-3

    Clean up Additive + 1% DGC-8 Clay Inhibitor + 2% GTH-1 Mutual Solvent +

    1% GTA-8 Drag Reducer + 93% filtered seawater.

B.  Unplugging Fluid:

     1.      Pre-fluid  

              W ater + 2% GTA-7 Demulsifier Agent + 1% GTA-3 Emission Assistant Additive

              + 2%GTA-6 Anti-corrosive Agent + 6% GTA-C Non- Acid Plug Removal Auxiliary

              Agent + 2% DGC-8 Clay Inhibitor + 2% GTA-11 Fe Stabilizer.

     2.      Main Fluid   

              Water + 5% GTS-F Non- Acid Plug Removal + 8.5% GTA-C Non-Acid Plug

              Removal Auxiliary Agent + 2% GTA-7 Demulsifier Agent + 1% GTA-3

              Emission Assistant Additive + 2% GTA-6 Anti-corrosive  Agent + 2% DGC-8

              Clay Inhibitor + 2% GTA-11 Fe Stabilizer.

 7 wells that showed increasing oil production at CNOOC SES Ltd are: