【作者】 赵芳；

【导师】 张忠诚；

【作者基本信息】 山东大学 ， 化学工艺， 2006， 硕士

【摘要】 油井生产系统中氯化钠的沉积是一个严重的问题。井下盐的沉积会导致油井的产能衰减，甚至会造成油井液流通道堵塞。采用注水技术清除盐垢是常用的工艺方法，但是这种方法要求消耗大量的通常不易得到的低矿化度水，不仅设备花费昂贵而且当环境温度低于水的冰点的时候不易操作。我们本着减少井底盐垢，提高油井产量，简化操作方法的目的，研制了一种用于石油开采的缓释性抑盐剂。抑盐剂防盐是一种向井中投入化学抑盐剂从而抑制结盐的有效方法，这种方法简便有效，但是也有它的不足，存在着加料频繁，有效周期短的问题。因此开发一种缓慢释放型抑盐剂，将解决这些问题，并存在着很好的研究价值和市场前景。 化学清防盐主要是应用盐抑制剂抑制结盐。其作用主要表现在2个方面：一是增加盐的溶解度，使之不容易析出结晶；二是改变盐的结构类型，将氯化钠结晶由致密的立方体结构变为疏松、细碎的絮状结构，使之容易清除和被流体带走，从而避免油井结盐或盐卡。实验证明亚铁氰化钠的抑盐效果非常好，其在溶液中的浓度对氯化钠的溶解度影响很大，一般60～100ppm即可以达到很好的抑盐效果。但亚铁氰化钠是一种易溶性无机盐，在水中具有较大的溶解度，因此必须选择合适的方法减缓它的释放速率。 我们采取两条思路进行抑盐剂的缓释实验。A)将抑盐剂用树脂进行包裹，通过改变配比及添加辅料改变释放速率。我们以亚铁氰化钠为主剂，环氧树脂，淀粉为辅剂聚酰胺树脂为固化剂，按比例7∶6∶3∶6制成直径为1.54cm高0.9cm的柱状样品颗粒。环氧树脂的固化反应没有水和其他副产物放出，固化后的树脂体系具有优良的耐酸碱，耐溶剂，和耐热性能，可有效阻止亚铁氰化钠渗出到溶液中。但环氧树脂是粘稠性液体，流动性较好，单纯采用环氧树脂和亚铁氰化钠混合，不易成型，且释放速率不易控制。淀粉是天然的有机高分子化合物，无污染易降解，而且遇水高温下糊化，具有较高粘度和韧性，加入一定量的淀粉，可以调节亚铁氰化钠的释放速率，也可以改善环氧树脂固化后结构，使之变成疏松网状结构。随着亚铁氰化钠的释放和淀粉的不断降解，最后剩下网状树脂骨架，较容易除去。实验证明，其释放速率已大大减慢并达到释放要求，它不仅有较好的缓释抑盐效果而且适合于井下的高温环境。B)将抑盐剂的有效基团转化成难溶盐形更多还原

【Abstract】 Precipitation of sodium chloride is a troublesome problem in many oil wells, which is extremely undesirable since it causes deposits which build up in conduits and in the formation itself. Such deposits often interfere with the flow of oil being produced from the formation. So the oil producing ability was decreased. In general, treating with fresh water has been used to remove sodium chloride deposits. However, such treatment is quite impractical when only a limited amount of fresh water is available or when the ambient temperature is below the freezing point of water. Since a large number of oil producing formations are located in areas where only small amounts of fresh water are readily available, it has also been very expensive and economically unattractive to perform fresh water treatments. We developed a kind of sodium chloride inhibitor with slow releasing rate, for the purpose of inhibiting salt deposition, increasing the yield of oil well and simplifying the operating process. It’ s an effective method of inhibiting salt deposition by throwing chemical inhibitor to the oil well. However it has shortcomings of feeding inhibitor frequently and short period of validity. So there is a good foreground and research worthiness to develop a kind of inhibitor with slow releasing rate.The chemical salt inhibitor operates by two ways: one is increasing the salt’ s solubility to inhibit the solution from crystallizing salt, and the other is altering the structure of the crystals from compact cube configuration to loosen and smash configuration, so it is easier to be cleared and brought out by the fluid. It is showed by experiment that sodium ferrocyanide is a good inhibitor. The concentration of sodium ferrocyanide influence the solubility of sodium chloride evidently, commonly there is a good effect when the concentration is 60～100ppm. Sodium ferrocyanide is an inorganic salt with good solubility, so we must try to slow its release rate.更多还原