Sodium Carboxymethyl Cellulose (CMC) and Polyionic Cellulose (PAC) in Petroleum Drilling: Applications and Functions
Sodium Carboxymethyl Cellulose (CMC) and Polyionic Cellulose (PAC) are essential additives in petroleum drilling, offering tailored solutions for diverse operational challenges. Below is an English introduction highlighting their applications in different drilling scenarios, suitable for corporate website product descriptions.
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| CMC High Viscosity | CMC Low Viscosity | Oil Drilling Grade PAC LV |
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| PAC LV | PAC R | Polyanionic Cellulose |
1. Sodium Carboxymethyl Cellulose (CMC)
Key Properties
CMC is a versatile anionic cellulose ether with excellent thickening, filtration control, and suspension capabilities. It performs reliably in moderate-temperature environments (up to 150°C) and is cost-effective for standard drilling conditions.
Applications by Scenario
• Drilling Fluid Formulation
• Viscosity Enhancement: Improves fluid viscosity to efficiently carry drill cuttings to the surface, preventing blockages.
• Filtration Control: Reduces fluid loss by forming a compact filter cake, stabilizing wellbore walls in porous formations.
• Saltwater Compatibility: Functions effectively in low-to-medium salinity environments without requiring additional preservatives.
• Completion & Fracturing Fluids
• Acts as a viscosity modifier in completion fluids and a cost-efficient alternative to guar gum in low-pressure fracturing operations, enhancing proppant suspension.
Technical Advantages
• Eco-Friendly: Non-toxic and biodegradable, meeting environmental regulations.
• Cost Savings: Low dosage requirements (e.g., 2.3–5.6 tons per well) and high slurry yield.
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2. Polyionic Cellulose (PAC)
Key Properties
PAC is a high-performance derivative of CMC with a higher degree of substitution (0.85–1.4). It excels in harsh conditions, including high salinity, extreme temperatures (150°C+), and high-pressure formations, while requiring 30–60% less dosage than CMC.
Applications by Scenario
• Complex Formation Drilling
• Saltwater & Offshore Drilling: Maintains stability in saturated brine and seawater environments, inhibiting clay swelling and minimizing formation damage.
• High-Temperature/High-Pressure (HTHP) Wells: Provides consistent filtration control and rheological stability in deep wells or geothermal reservoirs.
• Workover & Fracturing Fluids
• Low-Solid Workover Fluids: Reduces formation blockage and water influx, lowering maintenance costs.
• High-Efficiency Fracturing Fluids: Compatible with KCl solutions (up to 2%), rapidly forms gels, and delivers superior proppant transport in low-permeability reservoirs.
Technical Advantages
• Extreme Adaptability: Suitable for deserts, deep-sea drilling, and ultra-HTHP environments.
• Economic Efficiency: Reduced consumption and long-term cost savings due to enhanced performance stability.
Differentiated Applications Overview
| Application | CMC | PAC |
| Drilling Fluids | Standard onshore wells, moderate salinity | Offshore, high-salinity, HTHP wells |
| Filtration Control | Effective in low-temperature conditions | Superior in high-temperature, high-salt |
| Environmental Needs | Eco-sensitive land operations | Demanding marine/industrial environments |
| Cost Efficiency | Budget-friendly for shallow wells | Long-term savings in complex projects |
Technical Indicators
Technical Parameters of Petroleum Grade CMC
(Conforms to API Spec. 13A test methods)
| TYPE | Viscometer 600r/min reading | Filtration (ml) | ||
| In distilled water | In 40g/L salt water | Saturated Brine | ||
| LV-CMC | ≤ 90 | ≤10 | ||
| HV-CMC | ≥ 30 | ≥ 30 | ≥ 30 | ≤10 |
Technical Parameters of Petroleum Grade PAC
(Conforms to API Spec. 13A test methods)
| Type | Apparent Viscosity (mPa.s) | Filtration (ml) | Moisture (%) | Degree of Substitution (D.S) |
| PAC-LV | ≤ 40 | ≤16 | ≤10 | ≥ 0.9 |
| PAC-HV | ≥50 | ≤16 | ≤10 | ≥ 0.9 |
Technical Parameters of Ultra-high Viscosity Petroleum Grade CMC
| Type | Viscosity (1%, Brookfield, mPa.s) | Degree of Substitution (D.S) | pH | Purity (%) | Moisture (%) |
| CMC-5000 | 5000-6000 | ≥ 0.8 | 6.5-8.5 | ≥90 | ≤10 |
| CMC-6000 | 6000-7000 | ≤10 | |||
| CMC-7000 | 7000-8000 | ≤10 |
*We can customize according to the client's required specifications.
