Experimental study on piloted ignition temperature and auto ignition temperature of heavy oils at high pressure

Abstract

Explosion related safety problems of heavy oil and liquid oil are of great concern in energy related industries. For the petroleum industry, air injection assisted steam recycling (huff and puff) and in-situ combustion are important techniques for the exploitation and development of heavy oils, but a number of explosion accidents that occurred related to heavy oil have greatly restricted the application of the techniques. Aiming at the explosion problems in the air injection process for heavy oil production, the explosion conditions and characteristics of heavy oil-air mixtures at high pressure and high temperature were investigated via laboratory experiments using an improved explosion testing facility to simulate the explosion in a narrow pipe-like space. The effect of pressure (up to 15 MPa) on piloted ignition and auto ignition temperatures of different heavy oil types has been studied. The influences of pressure and properties of heavy oil on the evaporation and explosion detonation of heavy oil components were revealed. Based on the experimental and theoretical analysis results, the necessary conditions for the explosion and its influencing factors of heavy oil-air mixtures were determined, and the effect of average relative molecular weight of HC on auto ignition point was investigated.