塔河油田碳酸盐岩储层自生酸深穿透酸压技术

随着塔河油田碳酸盐岩油藏勘探开发区块向外围扩展，储层条件越来越差，需要通过酸压提高产能，高温条件下常规酸液酸岩反应速度快、滤失量大等问题严重影响了酸液深穿透效果。为此，研制了一种在高温下缓慢生酸的耐温型自生酸体系，该体系由高聚合羰基化合物（A剂）和含氯有机铵盐类（B剂）组成。室内试验结果表明，A剂、B剂的体积比为1:1时生酸能力最强，自生酸具有较低的酸岩反应速率及较好的酸蚀裂缝导流能力，且与塔河油田地层水及常用工作液体系的配伍性良好。该自生酸体系在塔河油田累计应用15井次，油井酸压后的自喷时间和产油量比邻井（未应用自生酸酸压）平均提高了1.5~2.5倍，取得了较好的增油效果。研究表明，自生酸深穿透酸压技术能够满足塔河油田碳酸盐岩储层深穿透改造的要求。 

Deep Penetrating Acid Fracturing Involving Self-Generated Acid in Carbonate Reservoirs of the Tahe Oilfield

Reservoir conditions are deteriorating as carbonate reservoir exploration and development blocks of the Tahe Oilfield extend to the periphery of the oilfield. Under such circumstances, it is necessary to improve productivity through acid fracturing. Higher acid-rock reaction velocities of conventional acid fluids under high temperature, and large filtration losses would significantly affect penetration performances of acids. To solve this problem, a temperature-resistant self-generated acid system was developed to generate acids under high temperature with lower reaction velocity. It consists of highly polymerized carbonyl compound (agent A) and ammonium salt (agent B). Experimental results showed that the largest acid volume can be generated when agent A and B volume are equal; the self-generated acid has lower acid-rock reaction velocity and better acid fracture conductivity. In addition, it is highly compatible with formation water and the common acid system used in the Tahe Oilfield. This self-generated acid system has been used in 15 wells in the Tahe Oilfield. The production in the primary production period after acidizing was 1.5 to 2.5 times of that of adjacent wells (without self-generated acid fracturing). The results showed that the deep penetration acid fracturing of the self-generated acid can meet the requirement for deep penetration stimulation of carbonate reservoirs in the Tahe Oilfield.