稠油掺稀管道输送工艺特性

Thermo-hydraulic features of a diluted heavy crude pipeline

对国内某WK掺稀稠油保温管道,进行工艺特性分析和安全输送能力计算。结果表明:1加热输送的掺稀稠油管道存在随输量减小压降急剧增大的不稳定区;2掺稀比增大时,管道的不稳定工作区左移,安全输送的临界输量减小,有利于管道在低输量下安全运行;3最大输送能力并非随掺稀比或首站出站油温单调递增;在某一掺稀比和/或首站出站油温下,WK掺稀稠油管道具有最大输送能力;4WK线的整体压降受掺稀比、输量的影响较大,但季节对压降的影响很小;5WK线整体温降主要受输量影响,而掺稀比、季节对其影响不大;6对于同一种掺稀比稠油和同样的出站温度,在不同季节下的末站进站温度、临界输量以及最大输送能力相近。

This paper investigated the thermo-hydraulic characteristics of diluted heavy crude insulated WK pipeline,and calculated the safe flow rate ranges. Results showed：①Unsteady working zones, which demonstrate sharp increases in pressure losses with decreased flow rates,occurred to the hot diluted heavy crude pipeline. ②With increasing dilution ratios,the unsteady zones moved to smaller flow rates,and hence safe working zones of the pipeline were enlarged. ③The maximum throughputs of WK pipeline did not increase monotonously with dilution ratios or/and its inlet temperatures,and its maximum pipelining capacities took place at certain dilution ratios and inlet temperatures. ④The total pressure drops of WK pipeline were considerably affected by dilution ratios and flow rates,but not by seasons. ⑤Flow rates had significant impacts on the total temperature drops of WK pipeline,but dilution ratios and seasons did not have such impacts. ⑥With regard to the same dilution ratios and inlet temperatures,the outlet temperatures,critical flow rates and the maximum throughputs of the pipeline differed little in different seasons.