COMPUTATIONAL ELEMENTS FOR THE REQUIRED NITROGEN DURING THE ICE PLUG ISOLATION OF A HORIZONTAL HIGH DIAMETER PIPE-LINE
The technique of forming controlled ice plugs in pipe-line installations in order to isolate a section from the rest of the circuit is used for carrying out circuit maintenance or repair activities without shutting down the entire installation. Considering the results from a controlled test that has been carried out on a horizontal 300 mm nominal diameter pipe-line section, we elaborated a calculation model to reveal the quantity of required liquid nitrogen. It resulted consumption 50 % higher than the actual one. The difference comes from the approximations made for the ice plug dimensions in each stage of the process.
The paper then describes the convenience of visualizing the formation of ice plugs by studying the formation of the ice layers on the pipe inner wall.
Keywords: isolating a pipe-line section, visualizing the forming of ice layers
Cuvinte cheie: izolarea unui tronson de conductă, vizualizarea depunerii de gheaţă