
腐蚀防护
减薄管内壁结蜡助力安全清管的措施
刘智广,元
李妍曾海伟1
赵文洲1
李媛媛1
李媛媛等:减薄管内壁结蜡助力安全清管的措施
摘要:独克DN377输油管道自输送中石化春光原油以来,近5个月未进行清管,冬季最冷月时管线运行压力呈明显上升趋势。分析异常参数可知,,
压力上升的原固是管内壁结蜡使管径减
小,反算析蜡高峰区位置缩径达46%,管线的输送安全受到威胁。为此,需采取应急措施维持管道安全输送,实验室实验及现场工业试验表明,选加注点注热案油与大排量冲剧相配合可有效减薄管道结蜡厚度。将上述措施应用于首次清管过程中,首次通球成功,未发生卡阻事故。目前该管线按照清管周期正常清管
关键词:清管;内壁结蜡;注热柴;大排量冲剧 Doi : 10.3969/j.issn.10066896.2017.12.020
Safe Pigging Measures of Thinning Inwall Wax Precipitation Li Yuanyuan, Li Yan, Zeng Haiwei, Liu Zhiguang, Zhao Wenyuan
Abstract: Duke DN377 oil transportation pipeline had not conducted pigging for almost five months since it began to transport Sinopec Chunguang crude oil. During the coldest month in winner, the pipeline operation pressure increased obviously.By analyzing abnormal parameters, it is found that the cause of pressure increase is the pipeline diameter decrease caused by inwall wax precipitation. Through back calculation it can be known that the pipeline diameter reduced by 46% in the wax precipitation peak area, which directly threatened the safety of pipeline transportation. Therefore, emergency mea sures are taken to ensure safe pipeline transportation. Tests in laboratory and field show that hot diesel injection at selected injection points and large displecement washing can effectively thin pipeline wax precipitation. By applying above medsures in the first pigging process, the first sphere pigging succeed ed, and no jam accidents happened. Now the pipeline normally conducts pigging according to pigging period.
Key words: pigging; inwall wax precipitation ; hot diesel injection; large displacement washing
原油长输管道输送过程中,必须定期清管以保证管道安全、高效运行。清管过程受油品物性、管道运行工况、管道内部复杂状况、管道本体变形情况等因索影响,且清管器在管内运行期间一且发生卡堵直接影响管线清管及正常输油作业。如异常过程参数未被及时发现,将会引发加压设备故障、管道凝管停输等重大事故,致使生产摊痪,经济损失巨大。对于首次清管的管线,上述风险更高。
1
管道运行现状
独克DN377输油管道起点为独山子区独山子
站,终点为克拉玛依区总站,1991年建成投产,设计输量300x10*t/a,设计压力6.4MPa。2012年停产,2015年9月启输四站一总站管段,后段经701一
新疆油田油气储运分公司 70
万方数据
总站调油复线自四泵站反输中石化春光原油。其辅送难点为:输送春光原油凝点较高(14℃),管线较长(88km),输量较低(1200d),补充哈国原油降凝后,冬季在最小输量附近跟难运行。
异常工况分析
1.1
2016年2月发现四泵站外输压力由0.8MPa升高至2.0MPa,并呈持续升高趋势,春光原油外输困难。分析原因主要是自投产以来,由于工艺受限、低输量等问题,管线长达近5个月时间未进行清管,内壁结蜡增厚。
管壁结蜡最厚的位置水力、热力共同指向四泵
站出站11.7~17.2km处,与管线轴向析蜡高峰区位置一致,单层结蜻厚度达到80mm,
管内径由
油气田地面工程httpu/wwwayqtdimgc.com