Table of Contents
Introduction of Super Sulphate Cement
Super sulphate cement is a particulr type of cement which is consist of ground granulated blast furnace slag. In short from, ground granulated blast furnance slag is known as GGBFS. Granulated blast slag as the main raw material, gypsum as a sulfate activator, and clinker and lime as an alkali activator.
Compared to regular Portland cement, super sulphate cement has significant advantages. It is made by grinding the raw materials to a specified fineness and mixing them evenly, without the need to bake the raw materials. The production of super sulphate cement is simple and environmentally friendly. It requires low energy consumption and low CO2 emissions.
Therefore, the application of super sulphate cement is not only helps in industrial waste recycling, but also saves energy and protects the environment. In particular, the heat of hydration of super sulphate cement is very low. Super sulphate cement has micro-expansion properties and excellent resistance to alkaline-aggregate reaction and sulfate attack.
Chemical Composition
Super sulphate cement contains 75-85% GGBFS, 10-20% sulphate and 1-5% alkali activator. Ground granulated blast furnance slag is the main component if super sulphate cement. This type of cement is also called as sulphate activated metallurgical cement.
Storage Tips
Great care should be taken when storing diluted cement, compared with Portland cement, because the risk of deterioration of this cement is higher.
Advantages of Super Sulphate Cement
- Less heat of hydration is released when super sulphate cement is hydrated.
- It provides resistance to sulphate attack.
- It consumes a large amount of gypsum compared to portland cement and thus helps in solid waste management.
- Its compressive strength is almost similar to that of OPC.
Disadvantages of Super Sulphate Cement
- Care should be taken when storing because super sulphate cement is easily degraded.
- It cannot be mixed with any other cement.
- It is not recommended for use at temperatures below 50 °C. This is because the rate of strength increase is quite reduced at lower temperatures.
- More water is required for curing, otherwise it will dry out and form a powdery surface.
Uses of Super Sulphate Cement
- It is used in foundations if foundations are located in chemically aggressive soils.
- Super sulphate cement can resist sea water attack better than portland blast furnace slag cement. Therefore, it can be used for concreting marine structures.
- Reinforced concrete pipes for burial in sulphate soil can be cast with super sulphate cement.