原油管道输送过程的热分析

由热量传递关系导出了原油管输过程不同性质热量计算公式,研究了输送过程原油损失热、释放热、油流摩擦热及其组成比例与输量或输送速度的关系.结果表明,油流摩擦热并非为输量增大后吨油输送耗热量降低的唯一原因,原油管中通过时间的缩短降低了输送过程单位质量沿线损失热.通过时间缩短且同时摩擦热增大的共同影响是输量增加后热经济性明显提高的主要原因.管道总损失热则与单位质量情况不完全相同,它取决于散热环境和油地温差,优化加热方案并使油地温差维持在合理水平,也可使总损失热随输量增大而有所降低.

Thermal Analysis of Oil Transportation Process in Pipeline

Based on heat transfer theory the thermal analysis for crude oil transportation by pipeline was performed in this paper. The formulae for calculating all kinds of caloric value were outlined. The regular patterns that these values and their component percentages vary with oil discharge rate were studied. Results showed that the friction heat, caused by water head loss during transportation process, was not a unique reason why the heat consumption for unit mass oil was down as discharge rate increased. The shorter the oil pass time in pipeline, the less is the heat loss for unit mass oil. Factors of both oil pass time and heat value of friction play an important role in upgrading heating economics. The total heat loss for pipeline was slightly different from the case for the unit mass. It depends on the condition of heat preservation for pipeline and the temperature difference between oil flow and soil that the pipeline was buried. If the heating scheme were optimized and the temperature difference maintained on a reasonable level, the total heat loss would also be down as discharge rate increased.