油井自生泡沫洗盐技术及其应用  

Salt Deposit Washing Technique in Oil Production Wells Using Gas-Generating Foaming Fluids

作　　者：尹依娜[1] 唐祖友[1] 黄雪松[1] 汪沈阳[1] 王咏梅[1] 马翠真[1] 崔连选[1] 

机构地区：[1]中国石化中原油田分公司采油工程技术研究院,河南濮阳257001

出　　处：《油田化学》2008年第2期115-117,174,共4页Oilfield Chemistry

摘　　要：中原油田一些区块的油井严重结盐，导致供液不足，产油量下降。对现用各种清防盐技术的应用效果进行了分析。清水洗盐法用于低压油井时有效期过短，洗盐周期为5～7天，其中生产期仅1～2天。地层水洗盐法效果略好，但用水量大，洗盐时间长，室内溶盐实验结果表明，洗盐水含盐量越大、流速越大。溶盐量越小。使用液体抑盐剂一般可延长洗盐周期5～10天，在产液量大、动液面高、结盐严重的油井只能延长洗盐周期1～2天，且固体防盐剂的释放速率和释放量不易控制。研发了通过两种溶液混合、反应、生成CO2气和N2气的自生气溶液体系，筛选出了一种复配起泡剂；在室内泡沫洗盐实验装置上，含1％起泡剂的自生气溶液起泡体系在60℃下以1．5和3．0m／s的流速通过储盐管，其溶盐量分别比清水增大54％和47％。在10口低压油井上用该泡沫体系洗盐，平均有效期超过30天，其中文13．160井的洗井周期由5天增至41天以上．产油量基本恢复。图2表3。The oil production wells in some districts of Zhongyuan are suffered from serious salt deposition troubles, causing insuffident fluids supplies and decrease in oil productivity. The effectiveness of various salt scale control techniques used in production wells are analyzed. The fresh water well washing is effective in a short time for low pressure wells and the period between two successive washing jods （PBWJ） is in range 5-7 days with 1-2 days of production being available. The formation water well washing gives better results by using a larger volume of water in a longer operating time and the laboratory tests show that the higher the salinity and the flow speed of the washing water used the less the amount of salt dissolved. The PBWJ can be elongated by 5-10 days by applying liquid salt precipitation inhibitors in general and by 1-2 days in wells of high fluids production and producing fluid level with serere salt scale troubles. The amount of inhibitor rdeased and the rdease rate from solidified salt precipitation inhibitors are difficult to control effectively. A gas-generating system of two chemical solutions, which produces gaseous CO2 and N2 in mixed state, is developed and a combinational foamer is selected. On a laboratory foaming/salt washing installation, the two gas-generating chemical solutions with 196 foamer added are mixed and flow through a salt pack at 60℃ at flow speed 1.5 or 3.0 m/s and the amount of salt dissolved is by 54% or 47% larger in comparison with fresh water. For well washing jobs by this foaming fluid on 10 low pressure wells, an average well washing life of more than 30 days is observed and, in particular, the PBWJ at well W-13-160 is elongated from 5 days for fresh water washing to more than 41 days and the oil production is practically recovered.

关 键 词：结盐垢 油井 洗井 自生气起泡体系 洗盐液 抑盐剂 低压油井 中原油田 

分 类 号：TE358.5[石油与天然气工程—油气田开发工程] TE39