高温对钻井液/完井液处理剂及体系生物降解性的影响研究

Influences of Biodegradability on Additives in Drilling Completion Fluids and Their Systems at High Temperature

实验测定了钻井液／完井液处理剂及体系在１４６℃的条件中作用２ｈ前后的ＢＯＤ５，ＣＯＤｃｒ值，并计算了ＢＯＤ５／ＣＯＤｃｒ比值。采用ＢＯＤ５／ＣＯＤｃｒ比值划分钻井液化学剂及油田化学剂可生物降解性的分级标准，对７种化学剂的可生物降解性进行了分级。结果表明，高温对钻井液／完井液处理剂及体系的生物降解性有不同程度的抑制作用：对化学需氧量影响不大，而对生化需氧量影响较大；对易降解物质的生物降解性影响不大，而对难降解物质的生物降解性影响较大。

Ratios of BOD 5 and COD cr of 7 kinds of chemicals in drilling/well completion fluids and their systems before and after treating for 2 hours in well are determined experimentally at a high temperature of 146℃ The ratio of BOD 5/COD cr is calculated and is adopted as the standard to classify biodegradability of chemicals in drilling fluids and oilfield chemicals 7 kinds of chemicals are classified The results show that a different degree suppression has taken place to biodegradability of drilling/well completion fluid additives and their systems at high temperature: the effect of BOD 5 is higher than that of COD cr , the effect of biadegradability of difficult degraded chemicals is higher than that of easy degraded chemicals, and more difficult degredation