Quote:
Originally Posted by burn_this_city
Nuclear has it's limitations, from what I understand there is a maximum distance (15km) you can send steam down a pipeline before it condenses.
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You're correct in that statement, but also incomplete in the scope.
That is for existing conventional CANDU reactors, who generate steam at around 4.7MPa. This will certainly limit the distance you can pipe the steam and still have it be useful for injection for SAGD as most schemes need pressure at the pad edge anywhere from 3 - 6 MPa with a high enough vapour content (steam quality).. and as there is no such thing as lossless distribution, that outlet pressure on the CANDU is just too low to fit the bill. The advanced CANDU designs can generate at around 6MPa, but that's still not great. On top of that, the reactor sizes and capital requirements are so large that you'd need to be supplying steam to a very sizable SAGD project (in excess of 100,000 bbl/d) to be economic. No company can be that confident in the reservoir performance at the beginning of a project. So the combination of reactor size, reservoir uncertainty and marginal steam conditions makes existing nuclear not a great fit with SAGD. If we ever had a successful low pressure SAGD scheme... then maybe but distribution is still an issue.
Here's a great paper with the details that point to the same conclusion you allude to:
http://web.mit.edu/finana/Public/oil...WhitePaper.pdf
In contrast, the molten salt reactor operates at higher temepratures than a CANDU reactor. With an MSR you can generate supercritical steam at the outlet of the steam supply system (12 - 25MPa). That really helps in breaking through that distribution problem, and even opens the door to possibly accelerating production by bringing on pads that are further out in the field earlier than you normally would. I haven't been able to assess that yet, but intuitively I think it makes sense. The low cost of steam would also allow the operator to enjoy a higher economic cut-off for steaming on a field wide basis which would allow the project to have higher ultimate recoveries or even "greenfield" a reservoir that might have been considered marginal under conventional means.