Manuguru
17° 03' N 79° 50' E

Indian heavy-water production supports domestic natural uranium [versus enriched uranium] nuclear power plants. Difficulties in supplying reactor inventories have been mitigated by nuclear power plant construction delays. A total of eight operating heavy-water plants have a total production capacity of more than 650 te/yr, adequate both to support current domestic requirements and export sales [including 100 te to South Korea and 350 te to Romania]. Six of the plants use ammonia exchange processes and are associated with fertilizer production plants, and the other two use the hydrogen sulfide process.

The plants at Manuguru and Kota, which are based on indigenously developed water-hydrogen sulphide exchange process, as well as the other ammonia based plants, have shown very good performance and safety records. Commissioning of the indigenously developed ammonia injection system for bringing down the dust particle in flue gases at the inlet of chimney of the Captive Power Plant at Heavy Water Plant, Manuguru to well below the specified norms was a significant achievement.

The Heavy Water Plant at Manuguru, Andhra Pradesh is based on the Bithermal Hydrogen Sulphide-Water (H2S-H20) Exchange Process. This plant with a capacity of 185 MTY is the second plant based on this process, the earlier one being at Kota, Rajasthan for which the complete technology has been developed indigenously by the BARC and HWB.

Based on the process package developed indigeneously a Captive Power Plant (CPP) is also set up at Manuguru. The CPP consist of 3 pulverised coal fired boilers and 3 nos. of extraction condensing turbines each capable of supplying 30 MWe. and the required process steam at 32 and 8 atm. pressure.

The main heavy water plant consists of two streams each designed to produce 92.5 MTY of nuclear grade heavy water and the process employed is the combination of two processes namely isotopic exchange reaction between H2S and H20 followed by vacuum distillation. As H2S gas is very toxic, corrosive and hazardous in nature and each stream will have dynamic hold up of 200 Te H2S, extreme care has been taken in the design of the plant, selection of equipment and materials adhering to stringent fabrication procedures and codes to ensure the production of heavy water in a safe manner. The exchange process operates at about 20 atm. pressure and at a temperature of 30 to 130 deg.C. while the vacuum distillation plant works at a pressure of 100 mm Hg absolute. The isotopic exchange reaction which is the heart of the technology is carried out with the aid of specially designed efficient trays. The H2S gas required for the process is manufactured in a separate unit at the plant premises by the chemical reaction between sodium sulphide and sulphuric acid.Very elaborate H2S detection instrumentation is provided not only in the plant but also in the surrounding areas to meet the requirements of the off-site emergency plans.

The Manuguru site was chosen because of its proximity to Singareni coal fields and Godavari river which provide respectively large quantities of coal and water required by the plant. The nearest rail head Manuguru is at a distance of 10 KM from plant site. The Manuguru Power Project is located in Khammam District northeast of Hyderabad.