原油裂解成气模拟实验、产物特征及其意义

AN ANALOGUE EXPERIMENT OF GAS GENERATING BY CRUDE OIL CRACKING,CHARACTERS OF PRODUCTS AND ITS SIGNIFICANCE

采用模拟实验方法 ,考察不同温度 (2 5 0～ 480℃ )、不同压力 (0 .1～ 5 0MPa)下原油裂解成气的演化特征。证明了高压可以降低油裂解的反应速度 ,抑制原油裂解 ;高压条件下比低压条件下的油裂解气更接近天然气的组成。讨论了LnC1/C2 与LnC2 /C3 间的关系。进行了裂解气碳同位素分析 ,证实了高演化阶段油裂解气的δ13C偏重确实与焦沥青裂解有关。建立了天然气单组分烃的δ13C与LgRo 间的关系式 ,其各组分Ro 适用范围 :C1为Ro<3% ,C2 ～C4 为Ro<1.7%。

The evolution characteristics of gas generating by crude oil cracking at different temperatures (250 ∼ 480 °C) and pressures (0.1 ∼ 50 MPa) have been investigated by use of an analogue experimental method. Through experiment it is proved that the crude oil cracking rate may be decreased at higher presssure, in other words, the crude oil cracking can be restrained; and the cracking gas generated at higher pressure is more similar to natural gas constituent than the one generated at lower pressure. The relation between ln C1/C2 and ln C2/C3 is discussed. By means of carbon isotope analysis of the cracking gas, it is indicated that the heavier δ13C value of the cracking gas generated in high evolution stage is indeed related to pyrrobitumen cracking. The relations between δ13C value and lg Ro for components C1 ∼ C4 are established and the Ro for various components are limited as follows: Ro2 ∼ C4.