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Vitreous enamel - tanks

Permastore Tank Shells for the Medupi Power Station 

The Medupi Power Station is a new dry-cooled coal fired power station being built in the Limpopo province of South Africa. When completed, the power station will have six high pressure boilers each powering an 800 Mega Watt turbine, producing 4800 Mega Watt of power and will be the largest dry-cooled coal fired power station in the world.


The boilers require extremely highly purified water, requiring the removal of all dissolved organics and suspended solids. The water is subject to many purifying processes including ultrafiltration, reverse osmosis, and electrodialysis to achieve the level of purity required by the boilers. During and after the treatment process, the water would be contained in 19 storage tanks which must retain the integrity of the quality of the water, and not allow any impurities from the tank coating to enter the water stream which could affect the operation of the high pressure boilers. The extremely tight parameters for the water quality specified a maximum silica content from the tank shells of < 1 ppb, and for operating temperatures between 30oC and 90oC. For such demanding containment requirements, PERMASTORE® Glass-Fused-to-Steel bolted tanks were chosen ranging in capacity from 85m3 to 5,000m3. The tanks were supplied via Permastore’s local Distributor in South Africa.


In order to confirm the suitability of PERMASTORE® Glass-Fused-to-Steel tank shells for this application, extensive independent testing was carried out on the Glass-Fused-to-Steel coating. The testing was carried out and confirmed that the Glass-Fused-to-Steel tank coating met the stringent parameters required for the demineralised purified water.


The tanks needed to meet a very tight schedule for supply and installation. This was another reason that the modular bolted tank design was chosen over the potential alternative of a welded design, which historically have a considerably longer installation period.  Permastore’s Distributor in South Africa completed the tank installation.


Permastore Limited has over 50 years’ experience as the leading manufacturer dedicated to the Glass-Fused-to-Steel tank and silo market in all regions of the world. Internationally recognised as the world’s leading dedicated Glass-Fused-to-Steel tank and silo manufacturer, Permastore has supplied more than 300,000 structures, installed in over 110 countries worldwide. Permastore is at the forefront of development of Glass-Fused-to-Steel (GFS) / Glass-Lined–Steel (GLS) tanks which are utilised to give customers the optimum solution for their containment requirements. 


Overview of Permastore's enamelling process:





































For further information and to see our tank build video please visit