Challenges and innovations in management and disposal of radioactive solid wastes

Radioactive solid waste generated from every step of nuclear fuel cycle are safely managed by applicable volume reduction techniques and conditioning before safe disposal to Near Surface Disposal Facilities (NSDF). Category-I is contributing about 85% (v/v) of total radioactive solid wastes. Out of the generated volumes, the cellulosic wastes form small fraction, and is managed by conventional diesel fired incinerators for achieving Volume Reduction Factor (VRF) of >30. Residue ash is cemented before disposal to NSDF. Rubber and plastic wastes, contributing about 40- 50% of the Category-I, are generated mainly from used plant protective equipment (PPEs) and decontamination procedures. At present they are compacted where VRF achieved is. Incineration of these wastes is associated with formation of dioxins and furans like toxic gases. Plasma pyrolysis system is developed and demonstrated in recent years to achieve higher VRF (about 30-40) in the management of rubber and plastic wastes with negligible probability for formation of dioxins and furans. Plasma pyrolysis demonstration facility installed at BARC, Trombay employing in-house developed plasma torch has successfully treated about 850 kg of mixed solid waste (cellulose (70- 80%) + rubber and plastic (20-30%)) including 501 kg of actual Radio Active Waste (RAW) (< 5 mR/hr contact dose). Radiological and conventional gaseous discharges are well within the regulatory limits. Representative sampling for dioxin and furans and in-house analytical methodology meeting international accepted standards is in advance stage of implementation