热历史和剪切历史对长庆含蜡原油凝点的影响

Effect of heating and shearing history on Changqing waxy crude oil condensation point

通过室内模拟长输管线热站的热历史作用、泵站的剪切和管流的剪切作用,定性分析了热历史和剪切历史作用对长庆含蜡原油凝点的影响效果,得知热处理温度是影响含蜡原油凝点变化的主要因素,高温热处理作用大幅度降低了含蜡原油的凝点,中温温度段的热历史作用会对含蜡原油凝点产生恶化效果;剪切历史作用是影响含蜡原油凝点的另一重要因素,低于200s-1的剪切作用会增大含蜡原油的凝点,高于400s-1的剪切历史作用对含蜡原油的凝点具有优化效果.热历史和剪切历史综合作用时,时间较短的中低剪速剪切历史作用对含蜡原油的凝点影响较小,高温和低温热处理作用有明显的降凝效果;长时间的高速剪切作用对含蜡原油凝点的影响明显,高温热处理和高速剪切综合作用对含蜡原油有较好的降凝效果.确定长庆含蜡原油的长距离输送热处理温度宜高于60℃,过泵剪切速率应高于200s-1.

Through the simulation of thermal history of the heat stations,shearing action of pumping stations in long-distance pipeline,we carried out an experimental study on waxy crude oil of Changqing oilfield with the shearing an heating action history,analyzed the effect of shearing and heating action on the condensation point of waxy crude oil,and came to the conclusion that heating history is the main factor affecting waxy crude oil. Contrary to medium temperature heat treatment,high temperature heat treatment reduces condensation point of waxy crude oil greatly. Shearing action is the other important factor which affects condensation point of waxy crude oil. Contrary to the shearing rate lower than 200 s-1,the shearing history with shearing rate higher than 400 s-1would reduce condensation point of waxy crude oil. After both the heating and shearing history action,short time,low or middle shearing rate action would result in a minor influence on the condensation point of waxy crude oil which is on the contrary to high or low temperature heating action. But long time shearing action would reduce condensation point of waxy crude oil greatly,and the integration of high temperature action and high shearing rate treatment would be the best effect on reducing condensation point of waxy crude oil. And lastly the appropriate temperature of heat treatment should be higher than 60 ℃ in long pipage transportation of Changqing waxy crude oil,pump shearing rate should be higher than 200 s-1.