沥青质沉积引起的储层损害与对策

Formation Damage Induced by Asphaltene Deposition and Measures for Damage Prevention and Removal

综述了近来受到国际石油界普遍关注的沥青质沉积引起近井地带储层损害的问题。综述论题有 :前言 ;原油沥青质吸附沉积过程及其对产能的影响 ;沥青质沉积的清除方法 ;结论。沥青质沉积对储层的损害和对产能的影响是不可忽视的 ,主要损害形式为孔喉堵塞、润湿反转和微粒运移等。沥青质沉积主要是原油所处热力学条件变化 ,原油中沥青质絮凝并沉降的结果。这类储层损害应以早期预防为主 ,一旦发生严重损害 ,应采取有效方法清除沉积的沥青质 ,使油井恢复产能。图 4参 32。

The formaton damage caused by asphaltene deposits in near bore zones as a problem deeply concerned by the international petroleum industry in recent years is reviewed. The topics covered are as follows: introduction; the processes of asphaltene adsorption and deposition and their effects on productivity; the methods of removing asphaltene deposits; conclusions. It is shown that the damage to reservoir formation and the negative influence on well productivity owing to asphaltene deposition can not be neglected in the processes of oil production; the damage are exerted mainly through blockage creation in pore throat, wettability alteration, and fines migration. The asphaltene deposition is the result mainly of asphaltene particles flocculation and precipitation in petroleum when the thermodynamic conditions changed. To this kind of damage early preventative measures should be the first approach to be tacken. Ones severe damage appears, some of the effective methods of asphaltene deposits removal must be adopted to restore the productivity of the oil wells.