Hydroxyethyl Cellulose (HEC) in Drilling Fluids
Product introduction:
Hydroxyethyl Cellulose, or HEC, is a non-ionic, water-soluble polymer derived from cellulose. Think of cellulose as the structural backbone of plants – the stuff that makes up wood and cotton. HEC is created by modifying this natural polymer with hydroxyethyl groups, making it readily soluble in water. This modification process gives HEC unique properties that are highly beneficial in drilling fluid applications.
It is essentially a thickening agent, much like cornstarch in gravy, but with added functionalities specifically tailored for the demanding environment of a drilling well. It increases the viscosity of the drilling fluid, helping to suspend drill cuttings and control fluid loss into the surrounding formation. Because it is non-ionic, HEC is less susceptible to interference from salts and other contaminants commonly found downhole, maintaining its effectiveness even under harsh conditions.
Specifications:
| Product Name | Viscosity (Brookfield 1%) | Substitution Degree | Application | Key Features |
| HEC-30 | 2000-3000 | 1.8-2.2 | Saturated salt drilling fluids | Salt-tolerant, maintains viscosity in high-salinity environments |
| HEC-35 | 2500-3500 | 1.8-2.2 | Freshwater-based drilling fluids | Excellent viscosity building, good fluid loss control |
| HEC-50 | 3500-5000 | 1.5-2.0 | High-temperature drilling fluids (up to 300°F) | Thermally stable, maintains viscosity at high temperatures |
| HEC-60 | 4500-6000 | 1.8-2.2 | High-viscosity drilling fluids, cuttings suspension | High viscosity, superior cuttings suspension, enhanced hole cleaning |
Application:
HEC (Hydroxyethyl Cellulose) is widely used in oil drilling, particularly in well completion, workover, stimulation fluids (fracturing), and borehole cementing.
Well Completion and Workover: HEC acts as a thickener, enhancing the viscosity of completion and workover fluids, improving sand-carrying capacity, reducing fluid loss, and stabilizing wellbore integrity, thus increasing operational efficiency.
Stimulation Fluids (Fracturing): In hydraulic fracturing, HEC is used to formulate fracturing fluids with high viscosity, enabling effective transport of proppants (such as quartz sand or ceramic beads) into fractures, ensuring sustained conductivity and enhancing oil and gas production.
Borehole Cementing: HEC serves as a rheology modifier in drilling fluids, helping control mud viscosity and fluid loss, reducing wellbore instability risks, and improving cementing quality while maintaining stability under high-temperature and high-salinity conditions.
Due to its excellent water solubility, chemical stability, and low environmental impact, HEC is an essential additive in modern oil drilling operations.
Steps and methods of making solution:
1. Add a prescribed amount of clean water to the container.
2. If hydroxyethyl cellulose is stirred at low speed, stir until all materials are completely wet.
3. Add other ingredients of the formula and stir well.
4. The surface-treated HEC will form a viscosity in about 30 minutes after dispersing it in water. Or after the material is completely wet, add alkali to adjust the pH between 8 and 10 to form a viscosity.
