Depressurization and augmented injection scale inhibitor for low-permeation water injection well and preparation method of depressurization and augmented injection scale inhibitor

Abstract

The invention provides a depressurization and augmented injection scale inhibitor for a low-permeation water injection well and a preparation method of the depressurization and augmented injection scale inhibitor. The depressurization and augmented injection scale inhibitor is prepared from the following raw materials: 10-12 parts of a nonionic surfactant, 18-20 parts of a triethylenetetramine-N,N,N',N'',N''',N'''-hexaacetic acid hexasodium salt, 5-8 parts of an anionic surfactant, 6-8 parts of an organic phosphonocarboxylic acid scale inhibitor, 2-5 parts of a dispersant, 15-18 parts of a diluents, 8-10 parts of an organic amine salt and 30-36 parts of water. The depressurization and augmented injection scale inhibitor for the low-permeation water injection well has the characteristic of multiple efficacy with one dose, is good in effects of swelling resistance, swelling shrinkage, corrosion inhibition and calcium sulfate and barium (strontium) sulfate scale inhibition when the dosage is 0.5 percent of water injection rate of the water injection well and barium sulfate solubility is improved by 3125 times at the temperature being 60 DEG C.

Description

technical field [0001] The invention relates to the field of oil exploitation, in particular to an anti-scaling technology for oil exploitation, and more specifically to a pressure-reducing and increasing-injection anti-scaling agent for low-permeability water injection wells and a preparation method thereof. Background technique [0002] Low-permeability reservoirs have poor reservoir properties, mainly low-porosity and low-permeability thin-throat reservoir structure. In addition, the content of cement is high, and the reservoir physical properties lead to high water injection pressure and difficult injection of water injection wells. [0003] Difficult water injection and high injection pressure are common problems in low permeability reservoirs. Analysis of the reasons for high water injection pressure: the fundamental reason is that low (ultra-low) permeability reservoirs have a starting pressure gradient, which must be overcome during water injection development to est...

AI Technical Summary

Problems solved by technology

[0004] An object of the present invention is to provide a kind of anti-scaling agent for low-permeability water injection wells; the anti-scaling agent of the present invention can solve the problem of refractory scales such as calcium sulfate, barium sulfate, strontium sulfate, etc. that cannot be solved by conventional chemical methods. It can remove the scale near the wellbore and inside the pipe of the water injection well, establish new pores and flow channels, restore the permeability of oil and gas flow, and realize the depressurization and injection increase of the water injection well