Scale and corrosion inhibitor for oilfield water injection and preparation method thereof

Abstract

The invention discloses a scale and corrosion inhibitor for oilfield water injection, which is composed of the following components in percentage by mass: 10-20% of oxidized amino trimethylene phosphonic acid, 5-15% of terpolymer, 2-8% of imidazoline-ammonium-salt, 0.5-2 parts of sodium gluconate and the balance of deionized water, wherein oxidized amino trimethylene phosphonic acid is trimethylene phosphonic acid, and is synthesized by heating and oxidizing amino trimethylene phosphonic acid and hydrogen peroxide at a temperature of 60-90 DEG C under alkaline conditions; the terpolymer is maleic anhydride-acrylic acid-polyoxyethylene ether acrylate terpolymer.

Description

technical field [0001] The invention relates to a water treatment agent and a preparation method thereof, in particular to a scale and corrosion inhibitor used for oilfield water injection. Background technique [0002] The secondary oil recovery process of the oilfield adopts sewage reinjection treatment, and the reinjection water contains a large amount of metal ions such as calcium, magnesium, strontium, barium, and CO 2 , SO 2 、H 2 S, Cl - And other corrosive gases, correspondingly bring problems such as calcium and magnesium scaling and corrosion of pipelines. In addition, there are various microorganisms in oilfield water, and the salinity is high, which aggravates the corrosion of pipelines and equipment, and even leads to pipeline perforation. Scaling of water injection pipelines can cause failures such as pipe plugging, pump jams, and increased water injection pressure, resulting in serious hazards such as decreased water injection efficiency and greatly reduced...

AI Technical Summary

Problems solved by technology

Most of the existing commercially available products cannot meet the oilfield water environment in some aspects. For example, although the patent publication number CN102911651 uses sodium molybdate with good effect as a film-forming agent, the entire compound components are water-soluble components, which are difficult to adapt to. Oilfield water and oily pollution agents are difficult to disperse, and cannot achieve the desired effect; although propanol or ethanol is used as oil pollution co-solvent in Patent No. CN102363886, they cannot play a stable role because of their low boiling point and easy oxidation; Another example is the narrow scope of application of GCS series oilfield scale and corrosion inhibitors, and the formula must be adjusted if the water quality changes slightly.