PGSS法用于脱油沥青颗粒的制备

Preparation of De-Oiled Asphalt Particles by PGSS Process

在超临界溶剂脱沥青装置上,以辽河稠油减渣为原料,得到脱沥青油的同时,用PGSS法直接对脱油沥青进行造粒实验。在压力为5.0～7.0MPa、温度为150～165℃的范围内考察了操作参数、喷嘴结构、脱油沥青性质对所得沥青颗粒分布的影响。压力增加、温度减小,50～100目沥青颗粒的质量分数增大,50目、40目、30目沥青颗粒质量分数减小,其中50～100目沥青颗粒的质量分数大于66%。喷嘴长度由13mm增加到40mm、内径由2.0mm减小到1.0mm,50～100目沥青颗粒的质量分数增大,50目、40目、30目沥青颗粒质量分数减小。压力增加、温度减小,脱油沥青的软化点增大。沥青性质的变化导致了沥青颗粒分布的变化。扫描电镜分析结果表明,所得沥青颗粒为不规则的多孔性物质,沥青颗粒的范围主要在50～100目。

At the same time of using supercritical solvent to produce the de-asphalted oil, the particles of de-oiled asphalt （DOA） were manufactured by using PGSS process with supercritical pentane as solvent at 155～170℃ and 5.0～7.0 MPa. The effects of operation parameters, the nozzle structure and the properties of DOA on the prepared particle size and particle distribution were investigated. The results show that, with the increase of operation pressure or the decrease of temperature, the mass fractions of 50 mesh, 40 mesh and 30 mesh particles decrease respectively, while that of 50～100 mesh particles increases; in each case, the mass fractions of 50～100 mesh, 50 mesh, 40 mesh and 30 mesh particles decrease in turn and the content of 50～100 mesh particles is over 66%. As the length of the nozzle increases or the diameter of the nozzle decreases, the mass fraction of 50～100 mesh particles increases and those of 50 mesh, 40 mesh and 30 mesh particles decrease respectively. The experimental results also indicate that the softening point of the DOA increases with the pressure rise or the temperature decrease during the de-asphalt operation, and the variance of DOA properties will lead to the change of the particle size and distribution. The SEM images of the prepared DOA particles show that the asphalt particles are irregular and porous , and the particle distribution is mainly in the range of 50～100 mesh.