Preparation of neutral compound scale inhibitor used for oil field reinjection water

Abstract

The invention provides a neutral compound scale inhibitor used for oil field reinjection water. The dosing is added according to the following parts by weight: adding 18-20 parts of self-made inhibitor, 25-30 parts of amino trimethylene phosphonic acid, 8-10 parts of acrylic acid-acrylic ester-2-acrylamide-2-ATBS ternary polymer and 20-22 parts of pure water into a reaction kettle for stirring for 30-60min with the temperature controlled at 20-35 DEG C; adding 14-16 parts of KOH within 30-45min, controlling the temperature below 60 DEG C, stirring for 90-120min, when cooling to below 30 DEG C, adding 8-10 parts of absolute alcohol, evenly stirring to obtain the compound scale inhibitor; synthesizing the self-made inhibitor, adding 25-30 parts of industrial acetic acid and 20-23 parts of pure water into the reaction kettle, stirring and slowing adding 33-37 parts of phosphorus trichloride within 30-40min, controlling the temperature below 40 DEG C for constant temperature for 15-30min, slowly raising the temperature to 110-120 DEG C within 30-60min, refluxing for 55-65min, carrying out cooling and reduced pressure distilling, when descending the temperature to 50 DEG C, slowly adding 15-18 parts of KOH within 30-60min, stirring for 60-90min with the temperature controlled below 50 DEG C, and cooling to room temperature. The addition of reinjection water in the preparation is 10-50mg / L. The preparation is also suitable for circulating water.

Description

technical field [0001] The invention relates to the antiscaling treatment of reinjection water in oil fields, in particular to the selection of antiscalant agents, in particular to the preparation of a neutral composite antiscalant agent for reinjection water in oil fields. Background technique [0002] Water injection is a commonly used method of oil production in oilfields. As the degree of exploitation deepens, the amount of water injection increases. The main thing is to reinject the produced sewage after treatment, but the produced sewage contains a large amount of calcium, magnesium, etc. Scaling-prone ions, they are easy to scale and precipitate on the inner wall of the pipeline under conditions such as temperature changes, affecting the normal production of the oil field. The use of chemical antiscalants to prevent scaling is a commonly used scale inhibition method for reinjection water in oilfields. This method is simple and easy to implement, but it is necessary t...

AI Technical Summary

Problems solved by technology

[0003] At present, the commonly used scale inhibitors are acid scale inhibitors or alkaline scale inhibitors. The commonly used acid scale inhibitors are single products such as hydroxyethylidene diphosphonic acid or their compound products. Corrosion of equipment and pipelines and high cost of use; commonly used alkaline scale inhibitors are single products such as ethylenediamine tetramethylene phosphate and their compound products, which have problems such as narrow application range and unsatisfactory scale inhibition effect

[0004] The present invention prepares a neutral composite scale inhibitor to avoid the disadvantages of equipment and pipeline corrosion, narrow application range, and high cost, and realize the purpose of low cost, high-efficiency scale inhibition and scale prevention, elimination of corrosion, and safe use