GEOSYNTHESIS ENGINEERING

Development and service of drilling fluid

Designed for drilling wells in the most difficult geological conditions - areas of possible complications associated with the instability of clastic sediments. PIBR-3 can be used to drill directional wells, lateral and horizontal wells, opening of productive horizons.

In most cases, PIBR 3 provides a higher recovery rate of reservoir permeability than traditional hlorkalievy solution. The distinguishing feature of a washing system PIBR-3 is used as the basic reagent-modified acrylic copolymer stabilizer AbramiX-K®. AbramiX-K® is the most potent inhibitor of organic clay rocks, allowing, in most cases, provide the necessary level of stability of the wells without the use of potassium chloride.

HISTORICAL REFERENCE

The successful use of a washing system PIBR-2 confirmed the high efficiency of the acrylic polymer as a reagent inhibitors clay rocks. At the same time, the use of caustic soda in obtaining AbramiX® reagent, does not fully implement its security features. Maximum inhibition was achieved polymeric reagent AbramiX-K®, the composition of which have been completely excluded sodium-containing ingredients.

ADVANTAGES

  • PIBR-3 preserves all the main advantages over traditional inhibited drilling fluids based on lignosulfonate reagents that provides system PIBR-2. As PIBR-2, 3-PIBR system characterized by:
  • The limit of thermal stability at low 150-180oC downhole fluid loss.
  • High lubricating and anti-seize properties (CTC system, without the use of additional lubricating additives, does not exceed 0.15-0.18), which eliminates the use of environmentally hazardous lubricants, especially oil. Additional advantages PIBR-3, before the washing system PIBR-2 are as follows.
  • A higher inhibiting effect on clay rocks provides a maximum attenuation of physical and chemical processes, which caused a decrease in the stability of the rock walls of the well;
  • It becomes possible to provide the necessary stability to wellbores "freshwater" mud without the additional input of potassium chloride, which leads to fewer components washing system, economy of reagents stabilizers and facilitates the interpretation of geophysical data.
  • To create the most favorable conditions for the activities of purification mud.

LIMITATIONS

  • When the concentration of polyvalent ions in the wash liquid filtrate more than 0.1% due to water seepage or razburki cement, may increase fluid loss and rheological properties. In such cases it is necessary to make the processing of drilling fluid with potassium carbonate (potash), and then, if necessary, enter diluents, and then - the reagents stabilizers.
  • A side effect of the use of reagent AbramiX-K® is a possible increase in the rheological and structural-mechanical parameters of the wash liquid. As compared with the system PIBR-2 thickening effect is manifested more intensively.
  • Thickening contributes to pollution of the washing liquid mud cuttings. In such cases it is necessary to reduce the solids content by dilution or cleaning solution, and the solution was treated diluents.

COMPOSITION AND PARAMETERS OF FLUSHING SYSTEM

Drilling fluid composition:

  • AbramiX-K® - 2-3% (on dry product);
  • CMC (PAC) - 0.1-0.2%
  • Thinning agents: РПС® - 0,1-0,5% combined with coal-alkali reagent or lignosulphonate - 0,3-0,5%;
  • Soda ash - up to 0,5% (periodically for admission of multivalent ions);
  • Graphite - up to 1% (before casing running);
  • Weighting agents (baryte, hematite, chalk, ground limestone) - depending on the desired density;
  • Drill cuttings slurry or bentonite - rest.
  • Potassium chloride as an additional inhibitor is used in the most difficult geological conditions. Depending on the specific situation in the well, the concentration of KCl can vary from 0.5 to 10%.

Parametrs of drilling mud:

  • Density - 1160-2300 kg/m3,
  • Funnel Viscosity - 80-120 s,
  • Gel - 60/90-100/140 dPa
  • Filtration loss - 6-8 cm3/30 min.,
  • HPHT fluid loss at reservoir temperature and pressure drop 5 МPа - 18-22 cm3/30min.
  • pH - 9.5-10.5.