Anti-scale agent used for barium, strontium and iron and preparation method thereof

Abstract

An anti-scale agent used for barium, strontium and iron and a preparation method thereof. The preparation method includes following steps: on the basis of the mass of the composition as 100%, filling a reaction kettle with 30-55% by mass of a synthetic derivative composed of dihexenyltriamine, nitilotriacetic acid, formaldehyde and phosphorus trichloride; adding 5-10% of EDTA, and 15-30% of a synthetic substance composed of acrylic acid and 2-acrylamide-2-methylpropanesulfonic acid; performing a stirring process uniformly and a heating process to 40-60 DEG C; slowly adding dropwisely ammonia water and stopping adding the ammonia water until the pH value of the solution is 7.3-7.7; continuously carrying out a reaction for 2 hours with stirring; adding a certain amount of clear water; and performing stirring uniformly to obtain the anti-scale agent specially used for barium, strontium and iron. By means of the anti-scale agent, generation of large amounts of barium strontium sulfate scale and ferric oxide precipitate due to mixing between injected water and oil layer water can be prevented. The anti-scale agent can satisfy a requirement of large different and continuous change of the injected water in a water injection system, has a good inhibiting effect on the barium strontium sulfate scale and the ferric oxide precipitate, is low in cost and is more than 90% in anti-scale rate when a medicine adding amount achieves 200 mg / L.

Description

technical field [0001] The invention relates to an oilfield descaling agent, in particular to a barium strontium iron scaling agent for preventing barium strontium sulfate scaling and iron oxide precipitation and a preparation process thereof. technical background [0002] During the production process of the Yanchang Oilfield, with the prolongation of the production time, the pressure of the oil wells in the exploited oil wells continued to drop, resulting in a sharp drop in oil production. Relying on elastic oil recovery could not meet the production requirements, and it was necessary to inject water into the exploited oil layers. Supplementing the pressure of the oil layer deficit, due to the limited amount of separated water of crude oil production fluid, and the fact that Yanchang Oilfield is located in northern Shaanxi, with poor geographical environment, part of the separated water of crude oil production fluid cannot be centrally processed and reinjected, and the inje...

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Problems solved by technology

When the two are mixed, calcium carbonate scaling will be generated at the temperature of the oil layer, and a large amount of calcium sulfate, barium sulfate, and strontium sulfate will be scaled. The oxygen in Luohe water will oxidize the ferrous ion in the oil layer water to produce a large amount of iron oxide precipitation. Due to the generation of carbonate scaling, sulfate scaling and iron oxide precipitation, the pressure of the water injected into the Luohe River in the Yanchang Formation oil layer increased greatly, and the rising speed was fast, and the water injection volume of the water injection well decreased significantly, and the injection requirements could not be completed, which seriously affected The implementation effect of oilfield water injection to stabilize production has restricted the sustainable development of oilfield water injection to increase oil production and the improvement of economic benefits

[0003] At present, a large number of corrosion and scale inhibitors on the market have a single scale inhibition effect, and cannot effectively control the mixed scaling and precipitation of sewage with high content of sulfate radicals, high oxygen content, high content of barium strontium ions, and high content of ferrous ions.

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