Provided herein are neutron-based detection systems and methods that provide, for example, high throughput analysis of elemental analysis of scrap materials. Such systems and methods find use for the commercial-scale evaluation of bulk process materials where hazardous or otherwise undesirable materials or high value materials may be interspersed with the primary process material. In certain embodiments, the system is used to detect and potentially remove unexploded ordinance (UXO) from a conveyor of demilitarized shell casings being recycled by detecting the presence of nitrogen and other elements present in the UXO. In other embodiments, the system detects and removes unwanted or highly valuable materials from a stream of scrap material.