油井防盐工艺技术研究及应用

针对中原油田油井结盐严重的问题，分析了盐垢的组成，盐垢的主要化学组成是Ｎａ＋、Ｃｌ－为主，含有少量Ｃａ２＋、Ｍｇ２＋、ＨＣＯ－３等离子，分析了盐垢形成的原因。通过室内试验提出了一种化学防盐新工艺，使用的化学防盐剂的防盐机理是在盐水中加入一定浓度的防盐剂，防盐剂将改变ＮａＣｌ晶体表面的电荷分布，破坏ＮａＣｌ晶核的产生，从而抑制ＮａＣｌ从溶液中结晶析出。防盐剂的主要作用是：增大盐的溶解度和改变盐的结晶类型。通过室内研究和现场试验表明：该技术工艺简单，施工方便，成本低，应用后取得了良好效果。

STUDY ON SALT PREVENTION TECHNOLOGY IN OIL-WELLS AND ITS APPLICATION

Salt deposition is severe in oil wells in Zhongyuan Oilfield.This paper discusses the composition of salt scale,and reason for formation of salt scale.Salt scale is composed of Na ,Cl -,and a small proportion of Ca 2 ,Mg 2 and HCO - 3.Having conducted tests,a new chemical salt prevention technology is recommended.The mechanism of salt prevention agent used is by add a certain volume of salt prevention agent to change the distribution of electric charge on the surface of NaCl crystal,thus destroy the formation of crystal nucleus of NaCl,and prevent NaCl from crystallizing out of solution.So,the main functions of salt prevention agent are to increase solubility of NaCl and to change the crystallizing type of NaCl.Indoor study and field tests prove the technology is simple,convenient with low cost and good results.