钻井液用甲酸盐含量测定方法  

Methods of Measuring Formate Content in Drilling Fluids

作　　者：张晓光 杨俊贞 王萍 李彬 李慧敏[1] 陈蕾旭 张灵英 ZHANG Xiaoguang;YANG Junzhen;WANG Ping;LI Bin;LI Huimin;CHEN Leixu;ZHANG Lingying(CNOOC Energy Technology&Services Ltd Drilling&Production Co,Zhanjiang,Guangdong 524057;CNPC Bohai Drilling Engineering Company Limited Mud Service Branch,Tianjin 300457;China National Petroleum Corporation Quality Supervising and Testing Center for Drilling Fluids,Tianjin 300457)

机构地区：[1]中海油能源发展股份有限公司工程技术湛江分公司,广东湛江524057 [2]中国石油集团渤海钻探工程有限公司泥浆技术服务分公司,天津300457 [3]中国石油天然气集团公司钻井液质量监督检验中心,天津300457

出　　处：《钻井液与完井液》2025年第2期233-238,共6页Drilling Fluid & Completion Fluid

摘　　要：针对当前钻井液用甲酸钠、甲酸钾标准应用现状,分析了甲酸盐含量测定存在的主要问题和影响因素,并筛选优化出最佳的检测方法。对于甲酸钠含量测定结果普遍偏高甚至超百的技术难题,通过红外等分析方法确定了目前钻井用甲酸钠的均为副产法产品,其含有季戊四醇等有机杂质,适合的方法是灼烧滴定法,同时对该方法进行了优化,实验发现该方法中灼烧产物的洗涤转移过程中引入酚酞会导致滴定终点延后结果偏高,通过改进洗涤转移过程,排除了该影响;对于甲酸钾含量测定,适合用硫代硫酸钠滴定法测定,同时增加钾离子含量测定,提高了方法的科学性和准确性,解决了以单一甲酸根折算甲酸钾含量存在无法有效鉴别低成本甲酸盐掺假的弊端。以上研究成果已作为标准方法引入T/CPSI 06401—2024《钻井液用加重剂甲酸盐类》标准,该标准已于2024年4月正式发布实施。In studying the standards concerning sodium formate and potassium formate as drilling fluid additives,the major problems existed in and factors affecting the measurement of the concentrations of formates were analyzed,and a best detection method was screened out through optimization of many methods presently in use.Methods for sodium formate detection presently in use generally give results that are higher than the true values and are sometimes higher than 100%.To solve this problem,several methods such as infrared spectrum measurement were used to detect the content of sodium formate in a drilling fluid,and it was found that the sodium formate products presently in use are all manufactured by byproduct methods,and contain organic impurities such as pentaerythritol.The method that found suitable for the detection of sodium formate is the burning titration method,which was optimized through experiment.It was found in laboratory experiment that the introduction of phenolphthalein when washing and transferring the burned product causes the titration endpoint to delay and the result obtained is thus higher than the true value.By improving the washing and transferring process,this negative effect was eliminated.It was also found that sodium thiosulfate titration method is suitable for the detection of potassium formate.Increasing the content of the potassium ions helps obtain more accurate results,eliminating the disadvantages of the old methods in which the content of potassium formate is calculated only from the content of formate radical and it is thus unable to identify the low-cost formate adulteration.The achievements of this study have been introduced into the standard T/CPSI 06401—2024 named“Weighting Agent for Drilling Fluid—Formates”,which was issued and implemented in April of 2024.

关 键 词：钻井液 甲酸钠含量测定 甲酸钾含量测定 

分 类 号：TE254[石油与天然气工程—油气井工程]