Ito Shumpei, Tanaka Yoshiaki, Hazuku Tatsuya, Ihara Tomonori, Morita Motoaki, Forsdyke Ivor
Research & Development Department, Yokogawa Electric Corporation, 2-9-32 Nakacho, Musashino-shi, Tokyo 180-8750, Japan.
Department of Marine Electronics and Mechanical Engineering, Tokyo University of Marine Science and Technology, 2-1-6 Etchujima, Koto-ku, Tokyo 135-8533, Japan.
ACS Omega. 2021 Feb 19;6(8):5310-5317. doi: 10.1021/acsomega.0c05415. eCollection 2021 Mar 2.
A method to estimate wax thickness inside petroleum pipes from the external pipe temperature measurements is proposed. When wax is deposited inside the pipe, the external pipe surface temperature decreases because the heat resistance of the wax reduces the heat flow from the fluid inside the pipe to the fluid outside the pipe. The decrease in the external pipe temperature can be calculated by solving a heat equation about the heat transfer from the pipe inner fluid to external ambient fluid, and thus the wax thickness can be estimated by measuring the pipe surface temperature. An experiment to validate the method was performed. Crude oil was passed through a pipe with an inner diameter of about 8 mm. Ten thermocouples were installed on the pipe. The pipe was covered by a heat-shrink tube as a substitute for an insulation material. The pipe was cooled by a coolant jacket, and wax about 0.8 mm thick was deposited in the pipe. The wax thickness estimated from the temperature measurements agreed well with the thickness estimated from the pressure rise because of the wax layer and from the final gross weight of the wax. The difference between wax thickness estimated from the temperature measurements and from the final gross weight was less than 0.2 mm.
提出了一种根据管道外部温度测量来估算石油管道内蜡厚度的方法。当蜡沉积在管道内部时，管道外表面温度会降低，因为蜡的热阻会减少从管道内流体到管道外流体的热流。通过求解关于从管道内流体到外部环境流体的热传递的热方程，可以计算出管道外部温度的降低，从而通过测量管道表面温度来估算蜡的厚度。进行了一项验证该方法的实验。原油通过内径约为8毫米的管道。在管道上安装了10个热电偶。管道用热缩管覆盖作为绝缘材料的替代品。管道由冷却套冷却，管道内沉积了约0.8毫米厚的蜡。根据温度测量估算的蜡厚度与根据蜡层压力上升和蜡的最终总重量估算的厚度吻合良好。根据温度测量估算的蜡厚度与最终总重量估算的蜡厚度之间的差异小于0.2毫米。
