微泡沫转向酸技术研究

发布时间：2018-01-01 21:12

本文关键词：微泡沫转向酸技术研究　出处：《西安石油大学》2017年硕士论文　论文类型：学位论文

【摘要】：泡沫酸化技术可以有效缓解常规酸化过程中酸岩反应速度过快,酸化效果不均以及酸化后含水量上升等问题。泡沫酸化可以使酸液进入低渗透层和油层,控制酸化后含水量的上升,使酸液达到转向分流的目的;但通常的泡沫酸化技术需要气源和注气设备等,增加了酸化施工的成本。本文围绕泡沫酸化技术,利用酸液与碳酸岩反应放出的CO_2为气源在储层中形成泡沫酸。同时使用气流法,岩心驱替实验装置等对泡沫酸的配方及缓蚀性能做了研究,并得出以下几点结论:(1)以CO_2为气源;通过加入不同的酸液添加剂组成稠化酸,复配酸,常规酸体系;并在三种酸液体系中加入不同起泡剂进行评价。实验得出在三种酸液体系中,起泡剂OP-10的泡沫综合指数最高;在常规酸和稠化酸中添加量为0.6%,在复配酸中添加量为0.45%时,就有较强的起泡性能,稳泡性能,耐矿化度和耐温性能。稠化酸和复配酸中相同浓度起泡剂的泡沫综合指数优于常规酸。(2)通过泡沫酸与碳酸盐岩屑的溶蚀实验可以看出,相同时间内泡沫酸的溶蚀率比酸液基液的溶蚀率小4%—10%左右,但温度越高,溶蚀速度越快;这说明泡沫酸有一定的缓蚀作用,可以有效的防止近井壁地带由于酸岩反应过度导致垮塌,并且可以对地层深部进行酸化。通过泡沫酸与20#钢腐蚀挂片的反应可以看出,泡沫酸的腐蚀速度低于酸液基液的腐蚀速度,且不会出现点蚀现象。在三种酸液体系中稠化酸与复配酸的腐蚀速度均低于0.4g/m2h。(3)通过单岩心暂堵和双岩心分流实验表明,实验所配置的泡沫酸溶液可以依靠酸岩反应自生CO_2气体形成白色乳状液状态的泡沫。所产生的泡沫酸可以有效封堵含水岩心,对含油岩心的封堵能力很弱。对渗透率极差为8左右的并联岩心进行驱替,泡沫酸会优先封堵高渗岩心,使酸液进入低渗岩心,对非均质地层较为适用。其中,黏度较高的稠化酸对岩心的暂堵和分流效果更好,但注酸时所需的压力较高,在实际应用泡沫酸时,应选择合适的酸液基液黏度。
[Abstract]:The foam acidizing technology can effectively alleviate the acid rock reaction speed over the conventional acidizing process, acidizing effect is uneven and the water content increased after acidification. The problems can make acid foam acidizing fluid into the low permeability reservoir and oil reservoir, the rising water control after acidification, the acid liquid to reach the purpose of diversion; but usually the need air foam acidizing technology and gas injection equipment, increase the cost of construction. This paper focuses on the acidification of foam acidizing technology, using CO_2 from the reaction of acid and carbonate source formation of foam acid in the reservoir. At the same time, using the method of gas flow, core displacement experiment device and inhibition of foam acid the formula to do the research, we draw the following conclusions: (1) using CO_2 as the source; by adding acid additives composed of different thickening acid, mixed acid, the conventional acid system; and to join in the three acid systems of different foaming agents Experiment evaluation. In the three acid systems, foaming agent, foam comprehensive exponent OP-10 is the highest; in the conventional acid and gelled acid added amount of 0.6%, in the mixed acid in the dosage of 0.45%, have strong foaming properties, properties of foam, high salinity and high temperature properties of foam. The comprehensive index is better than that of the conventional acid foaming agent the same concentration of thickening acid and mixed acid. (2) through the dissolution of foam acid and carbonate debris can be seen within the same time of foam acid dissolution rate than acid base liquid corrosion rate 4% - 10%, but the higher the temperature is, the faster the speed of dissolution this shows that; foamed acid has good corrosion inhibition effect, can effectively prevent the near wellbore due to acid rock reaction and can lead to excessive collapse, acidification of the deep strata. Hanging plate and 20# steel corrosion through the foam acid reaction can be seen, the corrosion rate of foamed acid is lower than the acid liquid The corrosion rate of the base fluid, and no pitting phenomenon. In the three kinds of acid corrosion rate of thickening acid and mixed acid were lower than that of 0.4g/m2h. (3) by single core and double core shunt plugging experiments show that foam acid solution experimental configuration can rely on the acid rock reaction of authigenic CO_2 gas to form white the emulsion state of foam acid produced by foam. It can effectively seal the sealing ability of water core, oily core is very weak. The parallel core on the permeability range of 8 about the flooding, foam acid will give priority to plugging high permeability core, the acid into low permeability core, suitable for heterogeneous formation. Among them, viscous acid of high viscosity on core plugging and diversion effect is better, but the higher pressure required when acid injection, in the actual application of foam acid, acid base fluid viscosity should choose suitable.

【学位授予单位】：西安石油大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TE357.2

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