RE:RE:RE:Posco America relocates HQ to Washington.....Maybe I'm late to the party in this analysis, but thinking further about the latest KPIs and the flow rate. I think they used the latest KPI release to maximize flow rate and see which KPI hit the constraint first which ended up being Lithium grade in product stream @25% or more. Where as the previous tests from 6.7 -> 9 flow rate seemed to have substantially higher purity with a more tapered dropoff from 6.7-9 in purity, but from 9 ->15.6, the purity went from 80% to 25% and concentration of lithium in stream went from 909 to 722 mg/L. I think this implies an exponential dropoff in purity
Now, while purity is apparently much less important cost wise to the total project, you don't exactly want to run a system toward the minimum of an acceptable KPI, and I've got to imagine that the fewer impurities in the stream, the easier and cheaper it is to convert to LHM. Sooo on a completely unscientific guess, I would say that the point of operation would be closer to 12-13 flow rate. Shoots the midpoint between the flow rates and likely is where impurities start to drop significantly while concentration in grade seems to be a fairly linear dropoff. So, I'd guess at a 12 flow rate, we'd have 60% purity and 800+mg/L of lithium in product at 92% recovery (also midpoint-between flow rates).
Just thinking out loud