Pre-melt won't melt metal.. neither would the main reactor (low temp). Residue clean-out is automated now -- no shut down (= no slow down). As for the % metal:plastic .. the rate of throughput (20 tons/day) is only limited by the condenser and not at all about the feeding of raw feedstock into the system. Therefore only the hydrocarbon mass rate-of-condensing will throttle the system. So even if ragger-tail is 50% non-plastic (by weight), the system should still approach 20 tons of hydrocarbon input per day.. or 40 tons of ragger tail. I would imagine that all other aspects of the system can keep up: feeder, pre-melt, residue, etc.