In sizes to handle gas volumes from 500 to 150,000 cfm, Series 6000 tray scrubbers have high-performance tray designs in single or multiple stages to achieve maximum gas absorption using once-through water at extremely low rates to absorb and concentrate products in one easy step, without needing recirculation pumps. The water flow pattern also enables recovery of higher vapor-pressure concentrated solutions for reuse. Where fine mists are formed, a final coalescing filter reduces emissions to extremely low, nearly non-detectable levels.