Acidification blocking remover composition for high pour-point oil-water well and blocking removal method

[0022] Take a sandstone well (static 67-55) in 2017 as an example: the well was injected 50 cubic meters a day before the measure, and the water injection pressure was 16.26MPa. Months later, the daily injection was increased to 120 cubic meters, the daily injection was 60 cubic meters, and the pressure was 16.2MPa.

[0023] In response to the above situation, the sandstone water well was unblocked again in the later stage, and an organic solvent composition (15%-20% C9 aromatics, 1.5% ammonium chloride, 1% nonylphenol polyoxyethyl ether , 1% sodium cetyl sulfonate and surplus water) 15 tons, mass concentration is 15 tons of hydrochloric acid aqueous solution of 15%, 30 tons of soil acid.

[0024] In the initial stage, 50 m3 was injected daily with a pressure of 3.8 MPa. After half a month, 120 m3 was injected daily with a pressure of 7.5 MPa. Compared with conventional acidification, the plugging removal effect was significantly improved.

[0026] In 2017, a carbonate oil well (Shen 625-18-30) was implemented. The well normally produced 10 tons of liquid per day and 6 tons of oil per day. After operation in October 2016, it produced 1 ton of liquid per day and 0.5 tons of oil per day. During the operation, it was damaged by cold and the iron scale on the pipe wall fell off and blocked the formation.

[0027] In view of the above-mentioned situation, use this formula to unblock it, squeeze into the organic solvent composition (15%-20% carbon nine aromatic hydrocarbons, 1.5% ammonium chloride, 1% nonylphenol polyoxyethyl ether, 1% sodium cetyl sulfonate and the remainder of water) 20 tons, the mass concentration is 90 tons of hydrochloric acid aqueous solution of 15%, 44.92 tons of water.

[0028] After the measures, the output returned to normal, with a daily increase of 5.5 tons of oil, and a cumulative increase of 1,360 tons of oil in the year, and the effect of plugging removal is remarkable.

[0029] Shenyang Oi