Drum for generator steam of HRSG boilers systems (Heat recovery steam generator) during construction in Combined-Cycle Co-Generation Power Plant. red steel framework building indoor perspective view illustration Drum for generator steam of HRSG boilers systems (Heat recovery steam generator) during construction in Combined-Cycle Co-Generation Power Plant. Many bridges over river in sunset, Harrisburg, Pennsylvania, Susquehanna river crossings aerial view, dramatic evening reflection in water Drum for generator steam of HRSG boilers systems (Heat recovery steam generator) during construction in Combined-Cycle Co-Generation Power Plant.