The figures show cement and concrete production stages, and it is obvious that producing concrete needs more time than cement because it has extra two steps in contrast with producing cement.
In the first step of cement production, limestone and clay are poured through the two rollers into a mixer. Then by means of a pipe, stuffs are conducted to a rotating heater. After heating, they break down to smaller pieces by the grinder. Furthermore, they are packed by bags after becoming cement.
In order to produce concrete, an amount of cement (15%) is mixed by water (10%) and then sand (25%) and gravel (50%) are added. All these four ingredients are mixed by using concrete mixer, and concrete is produced.
All in all, cement, needs more processes than concrete. On the other hand two gradients are mixed and crushing, mixing, rotating, heating and grinding septs are important to produce cement. However, after producing cement, for making concrete we only need to mix some ingredients.
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