SAFE-CARB ground marble bridging agent is a high-purity, acid-soluble calcium carbonate used as a bridging and weighting agent in drilling, drill-in, workover, and completion fluids. Compared with limestone, the agent features higher hardness and purity, providing better acid solubility.

This calcium carbonate bridging and weighting agent can be used in fluids ranging from conventional drilling fluids to advanced drill-in fluid systems, including

• FLOPRO NT water-based reservoir drill-in fluid
• FAZEPRO reversible invert-emulsion reservoir drill-in fluid system
• VERSAPRO invert-emulsion reservoir drill-in fluid system
• DIPRO high-density divalent reservoir drill-in fluid.

It can also be used with SEAL-N-PEEL fluid loss control pill to seal the inside of sand-control completion assemblies as a bridging agent and fluid-loss additive. Use OPTIBRIDGE software to select the optimal blend of SAFE-CARB agent to reduce fluid loss and minimize fluid and solids invasion.

The agent can also be added on a periodic basis for seepage control to limit losses to lost circulation and leak-off to high-permeability formations. It is particularly effective when drilling with high differential pressures caused by an overbalanced condition or when drilling depleted zones. Treatments range from 2 to 10 sacks per hour when used as a preventative measure. For depleted-zone drilling or induced-fracture applications, SAFE-CARB agent is most effective when used with

• G-SEAL sized graphite bridging agent
• G-SEAL PLUS wellbore stabilizing agent
• G-SEAL PLUS COARSE carbon-based bridging agent.

Median particle size (d₅₀) is reported as a size range due to variations in the manufacturing and grinding process. If a precise size distribution of a product is critical to a drilling operation, it should be measured with the appropriate recommended test procedure using samples that are representative of those expected to be used in that operation. Nominal d₁₀ and d₉₀ values are available upon request.

Imperial measurements

Volume of SAFE-CARB agent in lbm/bbl = (980 [w₂–w₁])/(23.3–w₂)

where
w₁ = initial mud weight in lbm/galUS
w₂ = desired mud weight in lbm/galUS.

Metric measurements

Volume of SAFE-CARB agent in kg/m3 = (2,800 [w₂–w₁])/(2.8–w₂)

where
w₁ = initial mud weight in relative density
w₂ = desired mud weight in relative density.

Applications

• Controlling fluid loss, density, and bridging in a range of fluids
• Sealing of sand-control completion assemblies

Advantages

• Minimized formation damage through high-quality, acid-soluble material design
• Effective bridging, especially when using OPTIBRIDGE bridging agent selection software to design an optimized, application-specific blend
• Simplified method of identifying the approximate d50 of agent
• High-hardness ground marble makeup that resists particle-size degradation
• Essentially inert for minimized effect on fluid properties 

Toxicity and handling

Bioassay information is available upon request. No claim of personal safety is intended nor implied by the use of the name “SAFE” in this product. Handle as an industrial chemical, wear protective equipment, and observe the precautions as described in the material safety datasheet (MSDS).

Packaging and storage

SAFE-CARB agent is packaged in 50-lbm [22.7-kg], 55-lbm [25-kg], and 110-lbm [50-kg] multiwall paper sacks. Store in a dry, well-ventilated area. Keep container closed when not in use. Store away from incompatibles. Follow safe warehousing practices regarding palletizing, banding, shrink-wrapping, and stacking.