丙烯酸十八酯-丙烯酰十八胺对原油流变性的影响

Effect of Octodecyl Acrylate-octyodecyl Acrylamide Copolymer on the Flowability of Waxy Crude at Low Temperature

研究了丙烯酸十八酯 -丙烯酰十八胺共聚物对中原 WC98- 2井原油流变性的影响 ,探讨了降凝剂的筛选、不加剂和加剂原油的全黏温曲线的测定、重复加热和高速剪切对加剂效果的影响和降凝剂的改性效果的时效性 .试验表明 :降凝剂使原油的凝点和反常点降低 ,原油的牛顿流体温度范围变宽 ,并且使非牛顿流体温度下的黏度减小 ,但是 ,牛顿流体温度范围内的黏度基本没有变化 ;重复加热的温度高于原油的反常点 1 0 0℃以上时 ,重复加热对降凝剂的改性效果没有显著影响 .但是 ,重复加热温度低于原油的反常点 ,重复加热显著恶化降凝剂的改性效果 ;在原油的反常点以上 ,高速剪切对降凝剂的改性效果无明显的影响 .在原油析蜡高峰区温度范围内高速剪切 。

Octodecyl acrylate octyodecyl acrylamide copolymer is used as pour point depressants (PPD) of the waxy crude oil of WC98 2 well in Zhongyuan Oilfield at low temperature. The influences of various factors on the rheology and thermal characteristics of treated waxy crude are discussed, and the following conclusions are drawn: (1) PPDs can depress the pour point and abnormal point of the crude oil. They makes the Newtonian liquid temperature scope of the crude oil become broader, and they decreases greatly the viscosity of non Newtonian liquid crude. (2) The influences of reheating and high speed shear on the effects of PPDs mainly depend on their temperature. When the temperature of reheating 10℃ above crude's abnormal point, reheating has little influence on the effects of PPDs. However, when the temperature is below crude's abnormal point, reheating deteriorates the effects; above abnormal point, high speed shear has little influence on the effects; when a great large of waxy crystals separate out, high speed shear deteriorates the effects.