原油与硫酸盐的热化学硫酸盐还原反应模拟实验及动力学研究

利用高压釜反应装置,在一定温度和压力下考察了吐哈原油和胜利原油与硫酸镁的热化学还原反应,热模拟实验在350～450℃含水条件下进行。利用库仑仪和气相色谱仪对反应后的气体产物进行分析,油相的总硫含量用库仑仪进行测定,固体产物组成利用红外光谱仪与X射线衍射仪进行分析,并对反应动力学进行了研究。结果表明,原油中的LSC含量对...

Thermal Simulation Experiments and Kinetics on the System of Crude Oil and Magnesium Sulfate

In the system of crude oil and magnesium sulfate, thermal sulfate reduction was conducted in autoclave under certain temperature and pressure conditions. The thermal simulation experiments were performed at 350~450℃ in the presence of water.  Gaseous products were analyzed using gas chromatography and microcoulometry. Gaseous products were composed of saturated hydrocarbons (C1 ~ C6), unsaturated hydrocarbons (C2~C5) and H2, CO2, CO. Content of CH4, H2 and CO2 increased with temperature growing. Gas dryness coefficient which was used to monitor the evolution of the hydrocarbon gas population also increased with temperature growing. Gas dryness coefficient of TSR was much more than Gas dryness coefficient of crude oil pyrolysis. It showed that the capacity of sulfate oxidization hydrocarbon increased with temperature growing. Total sulfate of the liquid products was analyzed by microcoulometry. At the begining, content of total sulfur in liquid products of TSR was higher than crude oil. It implied the reaction temperature for the system of crude oil and magnesium sulfate was lower than the pyrolysis temperature of crude oil. With the temperature growing, content of total sulfur in liquid products of reaction of Tuha crude oil and magnesium sulfate gradually reduced. It may be that large amounts of Labile Sulfur Compounds (LSC) contains in Tuha crude oil, whose degradation rate was higher than generation rate during reaction. While content of total sulfur in liquid products of reaction of Shengli crude oil and magnesium sulfate increaseed and then sharply reduced. It may be a lot of Stable Sulfur Compounds (SSC) contained in Shengli crude oil, which was hard to degrade in lower temperature. Solid products were analyzed by FT IR and X ray diffraction. MgO and MgSO4 were found to coexist in solid product of TSR. According to the the molar conversion calculated from the weight change of the solid products, the reaction kinetics was investigated. The activation energy of the system of Tuha crude oil and magnesium sulfate was 53.26 kJ/mol, while activation energy of Shengli crude oil and magnesium sulfate was 57.91 kJ/mol. Relative to the geological condition, the activation energy of crude oil and magnesium sulfate was lower. It was likely to be that the temperature of simulation experiment was higher than the critical temperature of water. Supercritical water could reduce the energy required to generate free radicals, which resulted in the faster reaction rate. The activation energy of the system of Tuha crude oil and magnesium sulfate was higher than activation energy of Shengli crude oil and magnesium sulfate.This maybe relate with content of LSC. It showed that content of LSC in the crude oil effected on the extent of reaction. The higher content of LSC, the stronger activity of TSR. In addition, the LSC has certain effect on the initial temperature of the TSR. LSC leaded to form reactive intermediates sulfate ester in the process of TSR. Sulfate esters were relatively unstable and would be expected to oxidize the hydrocarbon. This mechanism provided a possible explanation on the role of LSC in enhancing the rate of TSR at the initial stages. 