Summary of the invention
The objective of the invention is in the stratum; the heterogeneity of oil, G﹠W; and completion mud is analyzed the telescopic mechanism of corrosion; consider the protection formation contaminant simultaneously; prevent the stratum from collapsing and design a kind of substitute of mud; it has provide protection to casing corrosion, protects the borehole wall to prevent the pollution of the environment simultaneously, and its use can improve the quality of well cementation greatly.
The concrete scheme of this product is: its primary structure composition contains inhibiter, sterilant, stablizer, weighting agent and tackifier.Inhibiter is an amine inhibitor, primary amine or alkylamine or acid amides; Sterilant is diquaternary amine salt or dichlorophen or dioxide peroxide; Stablizer is by trivalent aluminium salt; Weighting agent is by powdered iron ore; Tackifier are polyacrylamide or Walocel MT 20.000PV (CMC).Each moiety scope by weight percentage is inhibiter 0.25%--1.50%, sterilant 0.15%--1.20%, stablizer trivalent aluminium salt 0.50%--3.00%, weighting agent 2.00%--5.00%, tackifier 0.50%--5.50%, slope soil 3.0%--11.0%, all the other are water; Function is the prevention casing corrosion, and the stable exposed borehole wall improves cementing quality; Principle is the amine inhibitor that is added with some amount in the protective material, can form layer protecting film at casing wall, has completely cut off like this because effects such as oxygen corrosion, bacterial corrosions.Contain sterilant, can avoid owing to the long-term bacterial reproduction that causes of placing, as sulfatereducting bacteria.Adding in the protective material has trivalent aluminium salt to prevent sleeve pipe caving in of exposed stratum outward as potent inhibitor.Good suspending power is arranged, and density, viscosity can be adjusted as required, require its Auto-regulating System of Density of Heavy Medium scope between 1.10-2.15 according to different well depths.
Oil drilling of the present invention well cementation specialized barrel anti-corrosive protecting agent mainly solves down-hole open hole section casing corrosion and protection question behind the oilfield well completion, prevents the open hole sloughing problem simultaneously.Its objective is that protective casing is not subjected to the corrosion of completion mud and local water etc., prolong oil well work-ing life, reduce the oil-field development cost.Using method is very convenient, can inject into well by spearhead is disposable when the completion well cementing operation, can carry out cementing operation.It has provide protection to casing corrosion, protects the borehole wall to prevent the pollution of the environment simultaneously, and its use can improve cementing quality greatly.Confirm that by experiment its effect is obvious, corrosion inhibition rate reaches more than 90%, can make with more than the regional oil well life-span prolongation 4-10, and tangible corrosionproof protection effect is arranged.
The implementation result corrosion inhibition rate all reaches more than 90%.
Embodiment
Embodiment 1:
Press routine composition and weight percent proportional arrangement, amine inhibitor primary amine 0.25%, sterilant diquaternary amine salt 0.15%, stablizer trivalent aluminium salt 0.50%, weighting agent powdered iron ore 2.00%, tackifier polyacrylamide 0.50%, slope soil 3.0%, all the other are water.Its protective material density is 1.10, is incubated 38 ℃, corrosion inhibition rate 91%.
Embodiment 2:
Press routine composition and weight percent proportional arrangement, amine inhibitor acid amides 1.50%, sterilant dioxide peroxide 1.20%, stablizer trivalent aluminium salt 3.00%, weighting agent powdered iron ore 5.00%, tackifier Walocel MT 20.000PV 5.50%, slope soil 11.0%, all the other are water.Its protective material density is 2.15, is incubated 38 ℃, corrosion inhibition rate 94%.
Embodiment 3:
Press routine composition and weight percent proportional arrangement, amine inhibitor alkylamine 0.88%, sterilant diquaternary amine salt 0.68%, stablizer trivalent aluminium salt 1.75%, weighting agent powdered iron ore 3.50%, tackifier polyacrylamide 3.00%, slope soil 8.5%, all the other are water.Its protective material density is 1.75, is incubated 38 ℃, corrosion inhibition rate 98%.
Embodiment 4:
Press routine composition and weight percent proportional arrangement, amine inhibitor alkylamine 0.40%, sterilant alkylamine 0.25%, stablizer trivalent aluminium salt 0.90%, weighting agent powdered iron ore 2.50%, tackifier polyacrylamide 1.00%, slope soil 4.50%, all the other are water.Its protective material density is 1.35, is incubated 38 ℃, corrosion inhibition rate 93%.
Embodiment 5:
Press routine composition and weight percent proportional arrangement, amine inhibitor acid amides 0.60%, sterilant dioxide peroxide 0.45%, stablizer trivalent aluminium salt 1.35%, weighting agent powdered iron ore 3.00%, alkene acid amides 2.00% in tackifier are poly-, slope soil 5.5%, all the other are water.Its protective material density is 1.50, is incubated 38 ℃, corrosion inhibition rate 96%.
Embodiment 6:
Press routine composition and weight percent proportional arrangement, amine inhibitor primary amine 1.00%, sterilant 0.85%, stablizer trivalent aluminium salt 2.00%, weighting agent powdered iron ore 4.00%, tackifier Walocel MT 20.000PV 4.00%, slope soil 9.1%, all the other are water.Its protective material density is 1.80, is incubated 38 ℃, corrosion inhibition rate 94%.
Embodiment 7:
Press routine composition and weight percent proportional arrangement, amine inhibitor alkylamine 1.20%, sterilant 1.00%, stablizer trivalent aluminium salt 2.50%, weighting agent powdered iron ore 4.50%, tackifier Walocel MT 20.000PV 5.00%, slope soil 9.5%, all the other are water.Its protective material density is 1.92, is incubated 38 ℃, corrosion inhibition rate 97%.
Embodiment 8:
Press routine composition and weight percent proportional arrangement, amine inhibitor alkylamine 0.88%, sterilant dichlorophen 0.68%, stablizer trivalent aluminium salt 1.75%, weighting agent powdered iron ore 3.50%, tackifier polyacrylamide 1.50%, slope soil 8.8%, all the other are water.Its protective material density is 1.80, is incubated 38 ℃, corrosion inhibition rate 96%.
The corrosion inhibition rate data obtain by following method and formula:
In the soak case, laboratory experiment adopts the lacing film method, gets interior poly-sulphur mud of well and configuration protection liquor ratio.Put into preceding weight-taking-up back weight=etching extent, the preceding weight=corrosion rate of etching extent/put into.
Calculation formula is as follows:
Average corrosion rate Fa=[(G1-G2) 3650]/(St ρ)
Unit: mm/a, in the a--formula:
Wherein: G1--test piece initial mass, g G2--test back test piece quality, g S--test piece surface-area, cm2 t--test period, d, d--days ρ--test piece density, g/cm3 gets 7.8.