Yep, you nailed on several important points. First, solids are going to be produced and disposed of as with current technology. Wouldn’t surprise me if if this used an old fashioned stabilization pond type bioreactor, which takes a lot of area and very likely to require tertiary treatment that would tilt the economics the wrong direction.
At this point, there is no data to decide one way or the other. If it turns out NOT to generate solids, IMO, this would be a major plus.
"Wouldn’t surprise me if if this used an old fashioned stabilization pond type bioreactor, which takes a lot of area and very likely to require tertiary treatment that would tilt the economics the wrong direction."
For this test reactor, they used two beakers. A wee bit early to talk about ponds and such.