油泥与油砂尾砂共混萃取回收油泥油的工艺研究

以辽河油田浮渣油泥和玉门油砂萃取后尾砂为研究对象,利用X射线衍射、扫描电镜和梯度筛分表征了其矿物组成、形貌特征和粒径分布。结果表明:尾砂主要含结晶度高的石英、碳酸钙,质地坚实,粒径大于75μm的颗粒占95%以上;油泥主要含黏土矿物,质地松软呈絮状,粒径小于75μm的颗粒占89.7%。根据两者性质上的差异性将其进行合理配比,提出了油泥、油砂尾砂共混萃取的新工艺。通过不同比例油泥与尾砂的共萃取实验,考察了尾砂?油泥质量比、溶剂?(油泥+尾砂)质量比、萃取温度、萃取时间等工艺条件对油泥油收率的影响,确定共混萃取最佳工艺条件为:尾砂?油泥质量比0.5、溶剂?(油泥+尾砂)质量比2、萃取温度60℃、萃取时间20min。在最佳工艺条件下,一级共萃取油泥油收率高达81.8%,二级共萃取油泥油总收率高达89.4%。共混萃取通过利用油砂萃取后尾砂作为萃取助剂,提高了油泥萃取的油分收率,对油泥的无害化和资源化工业生产具有参考价值。

CO-EXTRACTION PROCESS OF OIL SLUDGE AND TAILINGS TO RECOVER OIL

The mineral composition, morphology and particle size distribution of Liaohe scum oil sludge and Yumen tailing oil sands were characterized by XRD, SEM and standard size sieve. A new co-extraction process for mixture of oil sludge and tailings was proposed for oil recovery efficiently base on the different properties of sludge and tailings. The results indicated that the tailings are mainly composed of quartz and calcium carbonate with high crystallinity and the size of more than 95% particle is larger than 75 μm, while oil sludge mainly contains clay minerals with soft texture and 89.7% of particles with size less than 75 μm. The effects of tailings/oil sludge mass ratio, solvent/(oil sludge+tailings sample) mass ratio, extraction temperature and time on the oil recovery were investigated. The results showed that under the optimal operation conditions: 60℃ and contact time 20 min, tailings/oil sludge=0.5, solvent/sample=2, the oil recovery by one stage co-extraction is 81.8% and the total oil recovery by two stage co-extraction can be as high as 89.4%. It is concluded that the oil recovery from oil sludge can be improved by co-extraction of tailings and oil sludge.