| 摘要 |
Pipe assembly for long distance transport of hydrocarbon fluids which allows to control and remove wax deposits from the inner wall of the pipe. The pipe assembly comprises an outer pipe (1) and an inner pipe (2), the inner pipe being suspended in free inner ends of legs (4) extended in an annular space (3) that is formed between the outer and inner pipes. The legs (4) carry at their inner end a support foot (5) that is formed with a recess facing towards the inner pipe (2), thereby forming a tunnel (6), into which heater cables (10) are installed for direct heating of the wall of the inner pipe. Cooling water is introduced into annular volume (3) for cooling the wall of inner pipe. The process includes cooling of the fluid stream for solidification and precipitation on the pipe wall of substances which are dissolved in the fluid at higher temperatures. In a successive heating step the pipe wall is heated for a time period sufficiently long to cause the deposited solid particles to be released from the pipe wall and returned to the fluid stream for further transport as solids in a fluid which is now below the solids formation temperature. |
