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cess system). glycol (MEG), in to each and every

Subsea “The inclusion of subsea cool- pipe. Through evaluations, simula- ing, as a vital part of the process, tions and testing we have however infers stream temperatures decreas- made certain that inhibiting fuid is ing towards or even below hydrate properly distributed to all the pipes. formation temperatures. Inhibiting We can hence operate safely with- fuid, or anti-freeze if you will, is out unplanned shut downs due to therefore required in order to prevent hydrate clogging.” a hydrate plug from forming. Existing fow assurance challenges “On Åsgard, we have gone to and addressing hydrate formation on great lengths to keep us safe from Norway’s Ormen Lange development hydrates. For the Inlet Cooler, it has will be discussed been quite a focus and through thor- by Pabs Angelo, is “Global

This year’s UTC theme ough engineering and testing we feel senior fow as- subsea challenges, managing the old confdent that we have succeeded. surance engineer,

Subsea cooling and passive subsea Norske Shell. and the new.” The event will include the cooling is defnitely a feld for the Ormen Lange’s launch of a study commissioned from future,” Alfredsson says. fow assurance analysts Rystad Energy on the numbers

On Åsgard, the Inlet Cooler is system was up- of qualifed people in the industry designed to perform two functions graded in 2011 – cooling the hot gas coming back to include a new globally. The study shows where there from the compressor in an anti-surge pipeline monitor- could be gaps and helps the industry fnd event, and also to cool the well- ing system and possible solutions, including the most stream in normal production and in- leakage and block- important training/education facilities. crease the effciency of the compres- age module based sor station as a whole. By cooling the on a new transient

The event will be held June 19-20. wellstream, the compressor operates multiphase fow

For more information go to: at a higher effciency and, in addi- simulator, Flow- www.utc.no tion, more water and hydrocarbons Manager Dynamic. are condensed and can be pumped It has been able in the form of liquid rather than to give accurate predictions of pres- compressed as gas. sure, temperature, and fow rates of “The potential problem arises gas, condensate and water/MEG in when you cool your gas stream be- the wells, templates, fowlines and low the hydrate formation tempera- slug catchers.

ture,” Alfredsson says. “Not having It has also helped reduce the hydrate inhibitor available would “signifcant challenge” of hydrate mean that the pipe would eventu- and ice-formation by calculating the ally clog. And you have to bear in pressure, temperature, water content mind that there are a multitude of and MEG concentration through the pipes in this cooler. The challenge

Welltec’s WellCleaner tools lies within distributing the hydrate inhibitor, in this case monoethylene oedigital.com May 2013 | OE 93

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