高效固体防蜡剂的研制与试验

摘要

Paraffin deposit period is short in X block of Changqing oil field.Carbon number distribution mainly concentrates in C10～C51.The peak value is about C39.The high carbon wax presents high molecular weight and strong stability.The common paraffin inhibitor has the problem of strong pertinence and poor adaptability.According to the characteristics of waxy crude oil of X block,3 kinds of paraffin inhibitors were prepared and evaluated,wax control effect of the paraffin inhibitor for paraffin samples with different carbon numbers was analyzed by gas chromatography,and the main agent B of solid paraffin inhibitor was determined;The low melting point EVA-01 and high melting point LD-01 as the skeleton materials were compounded,then the dissolution rate was tested in different proportion,then the best ratio (2.5 ∶ 1)was determined;By analyzing the effect of JM-1 and FSJ-01,the formula of solid paraffin inhibitor was determined:10％B+85％(EVA-01/ LD-01 (2.5 ∶ 1))+5％ FSJ-01.When the paraffin inhibitor was 20 mg·L-1,the paraffin wax rate was 62.3％,and the wax precipitation point was reduced by 6.1 ℃.The field test showed that the solid paraffin inhibitor could decrease the load of the oil well and prolong the wax deposition cycle.%长庆油田X区块结蜡周期短,蜡质碳数在C10-C51之间,峰值在C39左右,呈现出蜡质碳数较高、蜡分子稳定性强的特点,常规防蜡剂防治困难,存在针对性强、适应性差的问题.针对X区块原油及蜡质特征,实验室合成的3种防蜡剂并进行防蜡率评价,应用气相色谱法对不同碳数范围的蜡样进行了防蜡剂防蜡效率的分析,确定出了固体防蜡剂的主剂B,可以适应C15-C51的蜡质;将低熔点EVA-01和高熔点LD-01的骨架材料复配,测试不同比例下的溶释速率,确定出两者最佳比例为2.5∶1;通过分析主剂B、分散剂FSJ-01加量的影响,确定出了固体防蜡剂的配方:10％B+85％(EVA-5/LD-03 (2.5∶1))+5％ FSJ-01.该防蜡剂在20mg·L-1时,防蜡率为62.3％,使原油析蜡点降低6.1℃.现场试验表明:固体防蜡剂可以降低油井载荷,延长结蜡周期,取得了较好的防蜡效果.