CSIR-Central Glass & Ceramic Research Institute
(A Unit of Council of Scientific and Industrial Research)

सीएसआईआर-केंद्रीय कांच और सिरेमिक अनुसंधान संस्थान
(वैज्ञानिक और औद्योगिक अनुसंधान परिषद की एक इकाई)
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Overview
  • Specialty Glass development and production constitute one of the major activities in CGCRI in view of their demand in the country for strategic applications. The main important variety of glass, which is currently either being produced for the Department of Atomic Energy are high density Radiation Shielding Window (RSW) glass. Starting from lab scale development, CGCRI has ventured into establishing pilot scale facility for technology demonstration and producing the materials to meet indigenous demand. Radiation Shielding Windows used in nuclear installations, are viewing devices, which allow direct viewing into radioactive areas while still providing adequate protection to the operating personnel. They are manufactured utilizing various types of glass blocks in densities from 2.5 g/cc to 5.2 g/cc. Glass blocks of 2.5 gm/cc are borosilicate type whereas the higher density glasses are based on PbO-SiO2-K2O system containing PbO in varying amounts. The density increases with increase in the content of lead in the glass. The glass blocks are stabilized against damage from radiation by introducing cerium in varying levels. The combination of glasses to be used in each window is worked out depending on the radiation shielding requirement and also for achieving optimum optical characteristics. Considering the essentiality of developing an indigenous technology to make the country self-sufficient for this critical item, CGCRI has taken up a major programme with the aim of achieving total indigenization in lead glasses required for RSWs under a MoU with BARC. As a logical extension to the lab-scale success, BARC and CGCRI, entered into an agreement towards attaining pilot scale indigenous manufacturing capability for producing larger size glass slabs. Under the terms of this agreement, CGCRI was required to not only scale up the high density glass production but also include in the manufacturing range medium density (3.9 gm/cc) glass blocks. CSIR-CGCRI has developed both un-stabilized and CeO2 stabilized RSW glasses of different sizes. Pt pot and bottom pouring technology (an indigenous technology) successfully demonstrated and pilot scale facility established for RSW glass blocks of sizes up to 400×400×100 mm and 700×700×35 mm. The reproducibility and reliability achieved in the aforesaid technology.
  • Management of radioactive wastes is an important issue that needs to be resolved if nuclear power is to make a significant contribution to the country’s power requirement.. The need is to immobilize high level radio-active liquid waste (HLW) within a molecular structure so that they will not come out of the structure and be released to the ambience. Glass has emerged as the material of choice for immobilization due to its unique random network structure. The glass bead in the five component borosilicate glass matrix comprising of SiO2-B2O3-Na2O-Fe2O3-TiO2 with the impurity level of chloride and sulphate less than 200 ppm is a critical material required for management of radioactive waste in a closed nuclear fuel cycle that is followed by India and has been indigenously developed by CSIR-CGCRI in the form of spherical shaped bead of desired sizes having stringent physical, chemical and mechanical properties. It functions as feed base glass to produce vitrified product during Immobilization of Radioactive Waste. In this process, glass beads with specific composition are fed into a high temperature Joule Melter along with HLW in a predetermined ratio to make the product glass with the desired properties. This ensures confinement of the radio isotopes in a stable matrix and safe disposal with no threat to the environment. The innovation provides waste volume minimization, recovery and recycles of valuables during nuclear waste immobilization and is of significant importance for the country’s nuclear power program. The material is now being commercially produced by M/s H. R. JOHNSON, Mumbai using this technology to meet the requirement of Department of Atomic Energy. The development of the technology is a significant step forward towards country’s self reliance in this important strategic sector. Till date around 42 MT of material of varying compositions had been supplied to the vitrification plants in Tarapur and Kalpakkam Atomic Power Stations. The demand is going to increase with the waste management being introduced to other units in the country. The success has brought a considerable recognition for CGCRI and CSIR as a whole for its contribution towards nuclear program of the country.

    Based on the successful commercialization of the aforesaid technology and utilization of the material for nuclear waste immobilization in DAE’s ancillary units at Trapur and Kalpakkam, DAE has now shown keen interest to the support of CGCRI in multi facet manner to sustain their nuclear program. The followings are the significant information in this direction:

  • Special Glass Nodules For Nuclear Waste Immobilization: Agreement for 7 Component Borosilicate Glass:
  • New Development on Low Melting High Sodium Content (Na2O: 23 wt%) Glass Beads:
ART OBJECTS DEVELOPED AT SIDC, CGCRI, KOLKATA




    Updated on: 03-09-2018 11:12 
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