利用重油梯级分离耦合萃余残渣喷雾造粒的方法将脱油沥青制成沥青粉,为脱油沥青提供了良好的应用前景.在连续溶剂脱沥青装置上考察了影响脱油沥青造粒的主要因素,原料为加拿大油砂沥青、委内瑞拉常压及减压渣油、中东减压渣油,溶剂为正丁烷、正戊烷、正己烷及其混合溶剂,萃取塔底温度分别为130、146、160℃,而副溶剂温度为130℃、150℃,压力为5MPa,溶剂比为4,喷嘴内径分别选用3、4、8mm,溶剂分散空间分别为受限空间及敞开空间,氮气气提流速分别为0.063 m·s-1、0.080 m·s-1.通过对脱油沥青颗粒进行拍照对比分析,发现影响因素主要有脱油沥青的性质、萃取塔底及副溶剂的温度、喷嘴内径、溶剂的扩散空间及氮气气提作用.要得到符合造粒要求的高硬组分含量的脱油沥青必须综合考虑原料及溶剂两种因素.适宜的萃取塔底及副溶剂温度、较小的喷嘴内径、溶剂扩散的敞开空间以及适宜的氮气流速均有利于喷雾造粒的顺利实施.%Using the spray granulation technology, the asphalt particles could be obtained from the de-oiled asphalt which is the coupled post-extraction asphalt residue of the heavy oil deep separation and the possibility of producing asphalt particles provides a nice prospect for the utilization of de-oiled asphalt In this paper, the influencing factors of asphalt particle production by spray granulation were studied with a continuous solvent deasphalting device; the feedstock used are Canada oil sand bitumen, Venezuela AR and VR, Middle East VR, respectively, and the other experimental operation conditions used respectively are as follows: n-butane, n-pentane, n-hexane and their mixture are used as solvents, temperatures at the bottom of the extraction tower are 130℃, 146℃ and 150℃, the auxiliary solvent temperatures are 130℃ and 150℃, the operating pressure is 5 Mpa, the mass ratio of solvent to feed is 4, the sizes of the nozzle (inside diameter) are 3 mm, 4 mm and 8 mm and the nitrogen flow rates are 0.063 m·s-1 and 0.080 m·s-1. The patterns of the asphalt particles produced under different operating conditions were recorded by photographs and compared with each other. It was found that the influencing factors mainly focus on several aspects, such as the property of de-oiled asphalt, the temperature at the bottom of the extraction tower, the temperature of the auxiliary solvent, the inner diameter of the nozzle, the diffuse space for solvent and the nitrogen stripping. In order to produce the qualified asphalt particles conveniently, both the feedstock and solvent used should be selected to let the asphalt could have high "hard component" content. Besides, the suitable temperature at the bottom of extraction tower and of the auxiliary solvent, a small size nozzle used, an open space for solvent diffusing and reasonable flow rate of nitrogen stripping, all these are favourable for the process of asphalt spray granulation.
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