[jabl]

> Are there any MSR designs that require NO reprocessing (whether online, batch or other)?

I think the Terrestrial IMSR (which is probably the one closest to commercializing in the West) is designed for a once-through uranium cycle, similar to current LWR plants. The idea, IIRC, is to replace the entire reactor vessel (including the fuel salt) every 7 years.

Not sure what the plan is for dealing with the spent fuel. If the fuel salt is water soluble (not sure, but salts tend to be, right?) I'd think some form of processing is necessary before geological disposal. But maybe that can be a cleaner and simpler process than a full PUREX.