DRILZONE L Low-Cost Surfactant | SLB


Low-cost surfactant

Schlumberger Oilfield Services

Designed specifically for onshore drilling, DRILZONE L low-cost surfactant improves ROP in water-based drilling fluid, especially when run with PDC bits. Its special blend of surface-active agents helps remove buildup of drill solids below the bit, enabling the PDC cutters to make continuous contact with new formation. As a result, bit and BHA balling as well as torque and drag are significantly reduced.

Typical Physical Properties
Physical appearance Yellow to brown liquid
Odor Very mild hydrocarbon
Specific gravity 0.78–0.85
Solubility in water Insoluble
Flash point 215.6 degF [102 degC]


For ROP enhancement, 1% to 2% by volume of the DRILZONE L surfactant should be introduced directly to the mud system at or near the pump suction over one circulation period—ideally, before drilling out the casing shoe. Alternatively, treatment can take place after a trip before entering the hole while the bit and BHA are clean. After the initial treatment, the product should be continually added or injected into the mud stream at the pump suction while drilling. The injection rate varies according to hole size, pump rate, dilution rates, and ROP.

Typically, addition rates range from 15 to 30 galUS [57 to 114 L] per hour of drilling. An injection pump attached to the low-pressure side of the mud pump helps to precisely control addition rates. DRILZONE L surfactant concentrations of up to 5% to 7% by volume do not affect drilling fluid properties or environmental toxicity.


  • Effectively increases ROP while drilling all shales
  • Improves bit life, reducing the number of trips
  • Reduces torque and drag
  • Improves mud filtercake quality and lowers fluid-loss values
  • Works well with high-performance PDC bits
  • Contains surface-active, metal-wetting agents that reduce the potential for bit and BHA balling
  • Does not induce foaming or aeration of the mud system


  • High-solids and weighted fluids above 14 ppg [1.68 g/cm3] can develop slightly higher viscosities and gels
  • Optimal performance may not be realized if the material is not added continuously in sufficient concentration while drilling
  • Some mud fluorescence is possible at high product concentrations
  • Some materials containing gilsonite or asphalts can partially solubilize in the presence of the DRILZONE L surfactant, which can promote sheening of offshore discharges

Toxicity and handling

Bioassay information is available upon request. Handle as an industrial chemical, wearing protective equipment and observing the precautions described in the safety data sheet.

Packaging and storage

DRILZONE L surfactant is packaged in 55-galUS [208-L] drums and is available in bulk. Store in a dry, well-ventilated area. Keep container closed. Keep away from heat, sparks, and flames. Store away from incompatibles. Follow safe warehousing practices regarding palletizing, banding, shrink-wrapping, and stacking.