The increasing prevalence of herbicide-resistant weeds in agriculture necessitates innovative, non-chemical weed management strategies. This study presents a novel approach for weed seed separation and devitalisation, designed for integration into combine harvesters to enhance field hygiene and reduce weed seed return. A new device was developed to selectively separate weed seeds and grain losses from the cleaning discharge, thereby reducing the power requirements compared to conventional hammer mill systems. Laboratory field tests conducted over four years demonstrated a separation efficiency of up to 93% for grain losses. Field trials indicated that the technology led to improved field hygiene and increased crop yields in treated plots. The device is suitable for retrofitting on various combine harvester models, supporting its broad applicability. This approach offers a sustainable and resource-efficient alternative tool for weed control. Further development and large-scale trials are recommended to optimize integration and assess long-term agronomic impacts.