AMPRI researchers find new application of red mud as X-ray shielding tiles

Red mud, also known as bauxite residue, is one of the most underused industrial wastes created during the Bayer process used to process bauxite into alumina. However, with time, more than 700 red mud applications have been patented by scientists, out of which only a few have been adopted by the industry due to reasons like cost, poor public acceptability, environmental concerns, etc.

One such application was recently made by the Bhopal, India-based research institute, CSIR Advanced Materials and Processes Research Institute (AMPRI). The researchers developed a method for turning red mud into X-ray shielding tiles using a ceramic process by including a certain weight proportion of high Z material and binder that is both environmentally friendly and economically feasible.

Dr N. Kalaiselvi, DG, CSIR, and Secretary, DSIR, Government of India, released the first flyer of the brochure outlining the success story of the topic, starting from fundamental, to applied, to commercialisation to Prism Johnson and deployment of the technology, during the Directors' Conference held in Palampur.

According to the research, the attenuation of the 12 mm thick tiles at 100 kV is equivalent to 2.1 mm of lead. The created tile also has a breaking strength of 3369 N and a flexural strength of 34 N/mm2, according to a statement released on Saturday by the Union Ministry of Science & Technology.

In place of the hazardous lead sheet, these tiles may be utilised to create radiation shielding structures in diagnostic X-rays, CT scanners, cath labs, bone mineral density, dental X-rays, and other imaging facilities to shield the public from radiation risks. On June 10, 2019, at CSIR, New Delhi, the know-how for producing "Lead-Free X-ray Shielding Tiles" was passed to Prism Johnson Ltd.

AMPRI, and Prism Johnson collaborated to scale up this technology from the lab to the commercial level. On April 14 of this year, joint-free X-ray shielding tiles (30x30x1.2 cm3) were produced on a pilot scale. The Atomic Energy Regulatory Board (AERB) of India evaluates and certifies the created tiles. The government commercialised the product, and the first shipment began at INS Kattabomman in Tamilnadu.