草桥稠油热-氧化降黏规律

Viscosity Reduction for Caoqiao Heavy Oil Under Low-temperature Oxidation

为实现稠油永久性降黏,对草桥稠油氧化剂辅助下热降黏行为进行了研究。用GSHA型高压反应釜模拟热采时的井下条件,从降黏率、裂解气组成和元素组成的角度分别考察了温度、氧化剂浓度对草桥稠油热降黏效果的影响。实验结果表明,加入2%H2O2时,草桥稠油的热降黏效果最好。加入适量的H2O2,反应温度越高,降黏效果越好。CO、CO2、H2S和轻质烃的生成,表明稠油中部分组分发生热裂解和氧化还原反应,稠油中轻质组分增加,实现了稠油的永久性降黏。由于高锰酸钾的强氧化性,使得草桥稠油黏度不降反增。在低温下适度的氧化作用有利于稠油降黏,但深度氧化会使稠油黏度升高。

In order to reduce viscosity of heavy oil irreversibly, the behavior of viscosity reduction was investigated under low-temperature oxidation. The GSHA high pressure reaction vessel is used to simulate the downhole conditions of thermal recovery. The effect of reaction temperature and concentration of oxidant on heavy oil viscosity reduction is investigated by studying viscosity reducing rate and cracked gas composition and elementary composition. The result indicates that hydrogen peroxide is beneficial to viscosity reduction. When the concentration of oxidant is moderate, the higher the reaction temperature, the better the viscosity reducing result. CO, CO2 and H2S generate in the course of thermal treatment, which suggest heavy oil cracks and oxidation. Potassium permanganate can＇t improve viscosity reducing result. Moderate redox can make the viscosity reduce at low temperature, while deep redox make the viscosity increase at high temperature.