OS PAYSAL S - Medium Viscosity, Highly Modified Starch
Reservoir Drill-In Fluid
OS PAYSAL SYSTEM comprises of specially ground and sized, pure Sodium Chloride salt as the main bridging agent, together with optimised levels of water based polymers to provide viscosity (particle suspension) and tight fluid loss control. The viscosifier is high quality Xanthan Gum and the fluid loss polymer is a specially modified polysaccharide intended purely for use in monovalent saturated brines.
Product Information
OS PAYSAL S is a highly modified polymer of medium viscosity with excellent fluid loss & filtercake producing properties. It is effective in fresh water but especially so in brines. It does not normally need any biocide as it is fermentation stable and has high thermal stability. It displays a useful synergy with xanthan gum exhibiting a high low-shear rheology in a static fluid and is very shear thinning in a dynamic one.
Typical Physical Properties
Type of product – Highly modified polymer
Appearance – Coarse, off-white free flowing powder
Suspension – Excellent in all types of drilling fluids, without lumping
Solubility – Readily soluble in all drilling fluid systems
Bulk density – 0.3kg / litre approximately
Fermentation – Completely stable
Thermal stability – Resistant up to 140°C in fresh water muds, higher in saline conditions
Advantages
OS PAYSAL S combines a medium viscosity with good filtercake producing properties, even in moderately Ca-++ contaminated muds.
Application
Specific flow and filtration characteristics make it an outstanding polymer for drilling fluids. It is suitable for low density as well as for high weighted muds, whatever the nature of the basis fluid may be, including many brine types. Drilling through calcium contaminated formations is possible with this product. Replacing CMC with OS PAYSAL S may also be a more economical option, mainly in seawater/brine muds.
Use: 3…12 lb/bbl depending on the type of drilling fluid.
Packaging
OS PAYSAL S is packaged in 50 lb sacks.

