It is intended for drilling of potentially unstable clastic sediments of the Lower Carboniferous DDI and opening of productive horizons (recovery rate of reservoir permeability is at a level that is achieved by using traditional chloro potassium solution).
The distinguishing feature of a washing system R-CPM is used as basic agent stabilizer condensed acrylic lignosulfonate Lignopol reagent. Unlike traditional CSSC, Lignopol has no effect on the dispersing argillaceous rocks, which can significantly increase the inhibitory properties chloro potassium washing system.
HISTORICAL REFERENCE
Despite the fact that the negative role of reagents lignosulfonate dispersant systems inhibited solutions is widely known, their use on the territory of the former Soviet Union is still very significant. In particular, in Ukraine, which has traditionally been used lignosulfonate reactants, the transition to the new polymer systems is associated with certain difficulties, mainly subjective. In addition, a lignosulfonate reagents characterized by a number of positive qualities, which are not characteristic of high molecular weight polymers. All this was a precondition for the development of new polymer-lignosulfonate reagents that allow to connect the advantages of the different classes of substances, and washing systems based on them.
ADVANTAGES
- High-inhibiting properties of the reagent Lignopol put him on a par with such organic polymeric inhibitors as AbramiX® and AbramiX-K®. At the same time, Lignopol exhibits significantly greater resistance to salts of polyvalent metals and has minimal impact on the rheological properties of drilling fluids. Application Technology Lignopol agent for the treatment of drilling fluids, similar to the traditional Ukrainian technologies CSSC, and does not require special training of staff. Thus, compared to conventional drilling fluids based CSSC system R-CPM has several advantages:
- Replacing lignosulfonate reagent CSSC on acrylic lignosulfonate reagent Lignopol allowed to dramatically increase the inhibitory properties of the mud due to the attenuation processes of dispersion and hydration of clay rocks.
- Lignopol has a high stabilizing effect. In systems inhibited drilling fluids Lignopol reagent consumption by at least 30% lower than traditional CSSC (KLST). In turn, the reduction of lignosulfonate component in the washing system leads to increase of its inhibitory properties.
- Thermal stability of the reagent system Lignopol inhibited solutions is at 140-150oC, which is significantly higher than that of CSSC, which today is produced in Ukraine and Russia.
- System R-CPM has a low downhole fluid loss, and has no tendency to thicken temperature. R-CPM does not require any special temperature stabilizers additives.
- Compared with the CSSC, Lignopol exhibits a significantly lower foaming ability.
RESTRICTIONS
- Efficacy reagent Lignopol reduced when the content of polyvalent metal ions in the filtrate of washing liquid level exceeding 0.12%. At a higher content of polyvalent ions before application Lignopol reagent, additional processing is necessary to make soda ash mud.
- When the primary processing of drilling fluids reagent Lignopol perhaps their thickening time. This effect is enhanced at high solids content, due to contamination of the washing liquid mud cuttings.
- Application Lignopol reagent may result in the need for defoamers.
COMPOSITION AND OPTIONS WASHING SYSTEM
THE COMPOSITION OF THE MUD
- Lignopol - 15-20%;
- CMC (PAC) - 0.1-0.2%
- KCl - 3-5% (if necessary, the concentration of KCl can be increased to 10%);
- CPF - 0.1-0.3% (if necessary, in the case of gelation);
- soda ash - up to 0.5% (periodically for admission of multivalent ions);
- Graphite - up to 1% (before running casing);
- weighting agents (baryte, hematite, chalk, ground limestone) - depending on the desired density;
- drill cuttings slurry or bentonite - rest.
PARAMETERS MUD
- Density - 1160-2300 kg / m3,
- viscosity - 50-90 sec.,
- SNA - 40 / 60-80 / 100 DPA
- fluid loss - 6-8 cm3/30 min.,
- downhole fluid loss at reservoir temperature and pressure drop 5 MPa - 18-22 cm3 / 30min.
- pH - 8-9.
