硫酸钡溶垢效果影响因素实验研究

为了研究溶垢剂DEED 溶垢效果的影响因素，采用失重法对溶垢剂开展了溶垢剂浓度、温度、时间以及pH 值 对溶垢效果影响因素实验研究。首先，采用化学方法对溶垢剂的溶垢机理进行分析，得出溶垢剂DEED 中能够与Ba2+ 发生螯合反应的主要官能团，从而更准确合理地解释各因素对溶垢剂溶垢效果的影响。其次，对影响溶垢剂溶垢效果 的因素进行实验研究。在实验条件下，溶垢剂浓度为9% 时，溶垢率高达82.41%。溶垢时间和温度对溶垢效果影响较 大，随着溶垢时间的增加，溶垢率逐渐增加，在前24 h，溶垢率增加幅度较大，符合油田施工要求。在溶垢时间为24 h 时，当温度从25 ?C升高到85 ?C 的过程中，溶垢率由32.02% 增加到82.88%。pH 值对溶垢剂化学结构中羧基的电离 度及鳌合性能影响很大，从而影响溶垢剂溶垢效果，在溶垢时间为24 h 时，当pH 值从6 增加到12 的过程中，溶垢率 从8.37% 增加到81.26%，在油田施工时，可以考虑注入碱性前置液。

An Experimental Study on Influencing Factors of Dissolution Effect of#br# Barium Sulfate Scale

To study the influence factors of the dissolving effect of scale dissolving solvent DEED，we conducted weight loss method experiments on the effects of solvent concentration，temperature，time and pH value on scale dissolving. First，we analyzed the scale-dissolving mechanism of DEED via chemical methods through which the main functional groups of DEED that can chelate Ba2+ are found. As a result，the reason behind different scale dissolving effects under various conditions can be explained more accurately and reasonably. Then，a number of experiments were conducted to study the influence factors of scale dissolving effect of the agent. Under the experimental conditions，when the concentration of scale-dissolving agent is 9%，the highest dissolving rate of 82.41% would be attained. The scale dissolving time and temperature have a great impact on scale dissolution. With the increase of acting time，scale dissolving rate gradually increases，and the scale dissolving rate increases greatly during first the 24 hours，which satisfies the requirement of field application. With a 24-hour dissolving time， dissolving rate increases from 32.02% to 82.88% as temperature increases from 25 ?C to 85 ?C. On the other hand，the pH value has a significant influence on the dose of carboxyl ionization and chelating performance of scale dissolving agent，thus affecting scale dissolving effect of the agent. With a 24-hour dissolving time，dissolving rate increases from 8.37% to 81.26% as pH value increases from 6 to 12. Thus alkaline pre-flush injection is recommended in oil field operation.