Friday, May 21, 2010

fracture fluids

Fracture Fluid
Guar gums are preferred as thickeners for EOR; guar gum and its derivatives declare for most of the gelled fracturing fluids. Guar is much irrigate meltable than otherwise gums, and it is also a punter emulsifier, because it has more galactose ramification points. Guar gum shows soaring low-shear consistency, but it is strongly shear-thinning. Beingness non-ionic, it is not artificial by ionic magnitude or pH but will degrade at low pH at conservative temperature (pH 3 at 50°C). Guar's derivatives support unchangingness in screechy temperature and pH environments. Guar use allows for achieving exceptionally towering viscosities, which improves the noesis of the fracturing liquifiable highly viscous pseudoplastic solutions of, mostly, greater low-shear viscosity than other hydrocolloids. The colloidal solids mouth in guar piddle fluids author prompt by creating little filter block. Proppant bundle conductivity is serviced by utilizing a changeful that has fantabulous liquid going command, much as the colloidal solids recognise in guar gum.

Borate cross-linked guar gum gels are both shear-thinning and thermally dilution; but on cooling, gel improvement is fast and thoroughgoing. These fluids are wise correctable gels since the crosslink junctions are not perpetual covalent bonds; they are short-lived, temporary junctions. The cross-linking agents do not abide any unchangeable chemical alteration during union disturbance at higher temperatures or deformation. The properties of the gel to be restored include the suppress of the cross-linking rates, smoothen suspending properties, and unrolled thermal stability . During a hydraulic fracturing discourse the liquid is transported eat the tubing into the fabrication. The subsequent temperature seem will alter the chemical counterbalance and the separate of cross-linked bonds; hence, dynamic the fluid's consistence. If the fluid's viscosity becomes too low, the cracking . Along with borate, zirconate crosslinkers person been victimized extensively in fracturing fluids. Piece the borates want thermal unchangeability (above 200oF), metal crosslinkers furnish trustworthy action up to liquid temperatures of ~350oF in impudent and saltiness.

1 comment: