Research On The Effect Of Temperature On The LTO Process Of Crude Oil

The DaQing crude oil was used to simulate Low Temperature Oxidation (LTO) under the DaQing oil reservoir condition. The effect of temperature on LTO was studied; The gas and oil composition after reaction were analyzed; temperature rise brought by thermal effect was also studied.Simulation experiments were carried out to study the LTO process. Crude oil reacted with air under reservoir temperature and pressure. The crude oil might react with oxygen more easily than diesel oil. The oxidation rate would be fast in the existence of porous medium. Different crude oil sample had diversity oxidation reaction state under oil reservoir condition. Pressure increasing accelerated oxidation rate .Oxidation rate was increased with the rising temperature. CO,CO2 were produced and O2 content reduced after LTO reaction. The O2 consumption was affected by temperature directly. O2 consumption rate increased evidently from 91.5℃to 120℃. It might give the evidence that crude oil began to be more activity in this region. O2 consumption increased rapidly before 175℃. Most O2 was consumed after 220℃and the residual content was 1.2% at 220℃.Component containing oxygen-functional group was produced after LTO reaction. Temperature and pressure are two influencing factors in LTO reaction procedure. Light compositions (Saturate, Aromatic) decrease while heavy compositions (Resin, Asphaltene) increase after air injection under oil reservoir temperature and pressure. The light compositions will reduce further with the rising pressure while the heavy compositions will increase further. The effect of the temperature is more complex in the LTO process. Different compositions may have diversity activity under different temperature. The crude oil viscosity will increase after LTO reaction. Heavy compositions may be split. So the crude oil viscosity will reduce. The oil density has little change.LTO procedure will generate heat. The heat increases with the rising temperature from 91.5℃and has a maximal value at 225℃. The temperature rise brought by thermal effect reduces after 225℃. Oxidation rate decreases at the region of 250℃-350℃.