轻油油藏高压注空气油与空气反应的活性研究

RESEARCH ON REACTIVITY OF OIL WITH AIR IN HIGH-PRESSURE AIR INJECTION AT LIGHT OIL RESERVOIRS

通过压力差热分析实验(PDSC)和热重与差热分析实验(TG/DSC),研究了鄯善轻油油藏原油在岩石矿物组成、温度、压力等的影响下,同空气反应的活性情况,以及由于氧化反应引起的自动升温及放热情况。结果表明,对鄯善油样,在温度低于300℃时,同氧气的反应能力很强,并能产生大量的热,同时增加压力能急剧提高氧化反应速度,在低温范围内,氧化反应放热量增加,热流曲线变得陡直;当压力达到4136kPa、温度215～220℃时油样表现出剧烈放热反应,出现气相中的燃烧或爆炸反应,放出大量的热;油样的氧化反应,也由于表面积的增加而加强,由于地层岩石中可能含有微量元素,起到催化作用,增进了油样氧化反应;在低温范围内鄯善油样有很强的挥发趋势,并没有反映出油样在气相中的氧化反应情况;同时油样具有较高API重度,低压条件下TG/DSC测试结果并不能全面反映氧化反应的趋势,高压条件下的TG/DSC或PDSC测试以及ARC测试是非常重要的。

By PDSC and TG/DSC,the reactivity of crude oil of light oil reservoir in Shanshan Oilfield with air is investigated with the influences of rock mineral composition,temperature and pressure and so on.Temperature increase and heat liberation caused by oxidation are also researched.The results show that for Shanshan light oil reservoir,when temperature is lower than 300℃,oil has strong reaction capability with oxygen,and a large of heat is released.At the same time,oxidation reaction rate can be increased sharply by increasing pressure.And in low temperature range,heat liberation of oxidation increases,heat flow curve is steep.When pressure reaches 4136kPa,oil shows violent exothermal reaction at 215～220℃,and burning or explosion reactions in gas phase take place with large heat liberation.The oxidation reaction of oil becomes stronger with the increase of surface area.Because of the catalytic action of microelement which may exist in formation rocks,the oxidation reaction of oil is enhanced.In low temperature range,Shanshan oil has strong volatility,and the oil oxidation reaction in gas phase is not shown.Because of high API of oil,TG/DSC results at low pressure can not show the trend of oil oxidation reaction completely,TG/DSC or PDSC at high pressure and ARC test are very important.