Methods, systems, and devices for PFAS destruction including providing water containing PFAS to a reactor vessel, irradiating the water with UV light under conditions to destroy at least a portion of the PFAS, passing the treated water through a selective membrane to form permeate and membrane reject comprising PFAS, providing the membrane reject back to the reactor vessel, providing additional water containing PFAS to the reactor vessel within the reactor vessel or before being provided to the reactor vessel, and irradiating the membrane reject and the additional water containing PFAS within the reactor vessel with UV light. The steps may be repeated a plurality of times such that PFAS that is not destroyed is recycled through the reactor vessel. Sensitizers may be added and may also be recycled in the membrane reject with the PFAS.

A low-carbon granulated metallic unit having a mass fraction of carbon between 0.1 wt. % and 4.0 wt. % is disclosed herein. Additionally or alternatively, the granulated metallic unit can comprise a mass fraction of phosphorous of at least 0.025 wt. %, a mass fraction of silicon between 0.25 wt. % and 1.5 wt. %, a mass fraction of manganese of at least 0.2 wt. %, a mass fraction of sulfur of at least 0.0001 wt. %, and/or a mass fraction of iron of at least 94.0 wt. %.

Reduced-waste systems and methods for granulated metallic units (GMUs) production are disclosed herein. A representative method can include receiving a first supply of molten iron and producing GMUs by granulating the molten iron poured onto a target material of a reactor. The method can include removing residual fines of the GMUs via a classifier based on a threshold particle size and mixing the residual fines with a second supply of molten iron to produce additional GMUs.