低损害高密度无固相压井液技术研究

发布时间：2018-05-08 20:32

  本文选题：高密度 + 无固相压井液　； 参考：《西南石油大学》2015年硕士论文

【摘要】：随着对东海油气田的勘探开发不断向深层和低孔低渗油气延伸,高温高压的问题日益突出,必须研发一种抗高温、低损害的高密度无固相测试液和压井液技术,以达到针对高温高压井的安全、高效测试和压井的目的。 本文首先对平北二期区块构造和沉积特征做了简介,并且通过对储层特征的分析,包括岩性特征、储集空间类型、物性特征、孔隙结构特征以及黏土矿物敏感性分析,得出了该区块潜在的地层损害因素：其水敏性不强,酸化时发生酸敏效应的可能性也很小,该区储集层岩石的非均质性都比较严重,空隙结构特征表现为孔喉直径小,孔喉结构以微孔微喉为主,易遭受微粒(伊利石)分散运移损害,也可能存在因孔隙结构中微观规模的气水分布不均,影响气水流动,造成水锁损害和贾敏效应。 由于无论无机盐还是有机盐在淡水或海水中的溶解度都是一定的,所以普通的无固相测试液和压井液体系密度一般不会很高,这样就造成了在高温高压井测试液和压井液的选择方面面临极大困难的结果。解决这一问题的办法是利用增溶技术来提高了无机盐或有机盐的溶解度,使测试液和压井液密度满足所需。然而,一般而言,当盐类在溶解度达到一定高度后,就会出现不稳定的问题。为此采用助溶剂技术克服了高密度测试液的稳定性问题,不仅具备很好的热稳定性,而且在运输和入井泵入过程中也具备很好的稳定性,保证了密度的在各种条件下的一致性。本文简单地对增溶技术和助溶剂技术做了介绍,并做了高温高压井目前所用钻井液的损害评价和东海目前所用无固相压井液的损害评价实验,以对压井液的研发给予借鉴和指导。最终以WJZ-1无固相加重剂、HZR-1增溶剂、NTA-2盐重结晶抑制剂和HCY-1缓蚀剂为基础,成功地研发了HWJZ无固相压井液体系,其抗温能力可达170℃以上,密度最高达1.80g/cm3。 在实验室内针对平北二期区块的储层物性岩性特点,通过大量实验,结果证明HWJZ无固相压井液体系能够抗高温、无毒性,起到很好的保护储层作用。 现场施工结果表明低损害高密度无固相压井液在高温条件下,性能稳定,保证了压井作业的顺利进行。
[Abstract]:As the exploration and development of oil and gas fields in the East China Sea continue to extend to deep and low porosity and low permeability oil and gas, the problem of high temperature and high pressure is becoming increasingly prominent. In order to achieve the safety of high temperature and high pressure wells, high-efficiency testing and well-killing purposes. In this paper, the structure and sedimentary characteristics of Pingbei II block are introduced, and the reservoir characteristics, including lithology, reservoir space type, physical property, pore structure and clay mineral sensitivity, are analyzed. It is concluded that the potential formation damage factors in this block are: its water sensitivity is not strong, the possibility of acid-sensitive effect in acidizing is also very small, the heterogeneity of reservoir rocks in this area is serious, and the pore structure is characterized by small pore throat diameter. The pore throat structure is dominated by micropore microlarynx, which is vulnerable to the dispersed migration of particles (Illite). It may also be affected by the uneven distribution of gas and water on the micro scale of pore structure, resulting in water lock damage and Jamin effect. Because the solubility of both inorganic and organic salts in fresh water or seawater is certain, the density of ordinary solid-free test fluids and well killing fluids is generally not very high. As a result, it is very difficult to select the well logging fluid and the well killing fluid in high temperature and high pressure wells. The solution to this problem is to improve the solubility of inorganic or organic salts by using solubilization technology, so that the density of test fluid and well kill fluid can meet the needs. However, in general, when the solubility of salts reaches a certain level, instability will occur. In order to overcome the stability problem of the high density test liquid by using the cosolvent technique, it not only has good thermal stability, but also has good stability in the process of transporting and pumping into the well, which ensures the consistency of density under various conditions. In this paper, the solubilization technology and solvent assistant technology are briefly introduced, and the damage assessment of drilling fluid currently used in high temperature and high pressure wells and the damage evaluation experiment of non-solid phase killing fluid used in East China Sea are made. To give reference and guidance to the research and development of well-killing fluid. Finally, based on WJZ-1 solvent-free weighting agent (HZR-1), NTA-2 salt recrystallization inhibitor and HCY-1 inhibitor, a solid free HWJZ well killing fluid system was successfully developed. Its temperature resistance was over 170 鈩，

本文编号：1862980