超稠油掺入焦化柴油辅助降黏脱水技术与应用

Viscosity Reduction and Dehydration Technology Assisted by Mixing Super Heavy Oil with Coking Diesel Oil

针对新疆某油田超稠油脱水时间长,破乳剂用量大,脱水效率低的问题,提出了掺入焦化柴油辅助处理超稠油热化学沉降脱水技术,室内考察了不同温度下、掺入不同种类稀释剂对超稠油黏度的降低幅度,在此基础上重点研究了超稠油提炼出来的焦化柴油回用于掺稀后对超稠油黏度、旋流除砂、破乳剂加药浓度以及脱水效果的影响,并进行了掺入焦化柴油现场试验。研究结果表明:在超稠油中掺入柴油可缩短超稠油热化学沉降脱水时间,降低破乳剂加药浓度。现场掺入9%的焦化柴油后二段沉降罐满罐后即可达到净化油含水合格指标,掺入5%的焦化柴油后二段平均沉降仅需13.4 h,较掺入柴油前二段平均需27.8 h的沉降时间有了较大幅度的缩短;掺入柴油后破乳剂SB-1加药量可降至100 mg/L,较掺入焦化柴油前的220 mg/L降幅达54.5%。此外掺入焦化柴油还可增强旋流除砂效果,降低原油黏度,结束了现场罐车拉运的历史,实现了超稠油长距离的管道集输,较之前罐车拉运成本降低40%以上。

Aiming at the problems of long dehydration time,large amount of demulsifier,and low dehydration efficiency of a certain heavy oil field in Xinjiang,a thermochemical sedimentation dehydration technology assisted by mixing super heavy oil with coking diesel oil was proposed.Experiments were carried out in the laboratory to reduce the viscosity of super heavy oil by adding different kinds of diluents at different temperatures,and the effect of the coking diesel oil extracted from super heavy oil on viscosity,cyclone desanding,demulsifier dosing concentration and dewatering was studied.The results showed that when blending coking diesel oil into the super heavy oil,the dehydration time of thermochemical sedimentation of super heavy oil was shortened and the concentration of demulsifier was reduced.When the second stage sedimentation tank was filled with super heavy oil blending with 9%coking diesel oil,the qualified water cut index of purification oil could be achieved as soon as the tank was full,and the average settling time of the second stage sedimentation tank filled with super heavy oil blending with 5%coking diesel oil was only 13.4 h,while the settling time before blending with coking diesel oil was 27.8 h.Moreover,the dosage of demulsifier SB-1 could be reduced to 100 mg/L after blending super heavy oil with coking diesel oil,which was 54.5%lower than that before blending,being of 220 m g/L.In addition,the addition of coking diesel oil could also enhance the swirling sand removal effect,reduce the viscosity of crude oil,end the history of on-site tank truck transport,achieve the long-distance pipeline gathering of super heavy oil,and reduce the cost by more than 40%.