new technology to produce cement from gypsum instead of using limestone
You can't produce OPC without limestone and gypsum. Both are needed. You can find out only alternative material for individual material. You can't replace limestone by gypsum or gypsum by limestone to produce OPC.
Indeed, you need a source of lime in the clinker and this may only be obtained by calcining limestone. Calcining gypsum will only yield different forms of anhydrite (CaSO4).
Besides, remember that the gypsum addition is very few with respect to clinker (~5%) in order to balance the C3A hydration. Going over this will result in much trouble, especially with respect to durability.
In Spain we have a traditional Plaster to 1100 we can qualify for hydraulic plaster. The raw material is plaster (90%) and clay (10%) . The result is a mortar anhydrite and bassanite some calcium silicate phases
To produce clinker should be used about 75% lime stone it is source of CaO, some times used minor quantity of gypsum to make balance with alkalies ,
To produce clinker should be used about 75% lime stone it is source of CaO, some times used minor quantity of gypsum to make balance with alkalies , If used more gypsum it is more volatilize SO3 is kiln and build up happen
In any case if you replace limestone by gypsum you will not get Portland cement whatsoever.
To produce OPC you need limestone and clay. Gypsum is needed in low quantity. By calcining gypsum (dehydrated calcium hydroxide) at relatively high temperatures (more than 500 ºC) you can produce an hydraulic binder, composed by calcium sulphate (anhydrite), but not OPC. Anhydrite can be used for plasters or for decorative elements but as long as I know it is not used for structural elements.
Usually gypsum is used in low quantity (about 5%) in order to control the setting time of cement and control C3A. Adding more gypsum will affect the quality of cement and tits setting time. Gypsum can be added to cement for non-structural elements for example for plastering.
Usually gypsum is used in low quantity (about 5%) in order to control the setting time of cement and control C3A. Adding more gypsum will affect the quality of cement and tits setting time. Gypsum can be added to cement for non-structural elements for example for plastering.
Usually gypsum is used in low quantity (about 5%) in order to control the setting time of cement and control C3A. Adding more gypsum will affect the quality of cement and tits setting time. Gypsum can be added to cement for non-structural elements for example for plastering.