Use of Copper Slag in Concrete

Will turn green overtime (?) S.M.

I hadn't thought of that, but you are probably right.

Is it possible to use copper slag (waste from furnace) as partial replacement of portland cement? YES -but after detailed understanding /research. See these:

· The main kinds of metallurgical slags are:

Fast-cooled iron blast furnace slag (ggbs), steel slag, phosphorus slag,

Copper slag and Lead slag.

Due to their chemical and mineral

composition, these slags have cementitious and/or pozzolanic

properties and can be potentially used as cement main constituents.[This from Greece Research]-----------------

· Non Ferrous Slag products Copper Slag (CS)

Molten copper slag is produced by the reduction of ores and fluxes to liberate the copper metal. It is generally granulated to form very dark colored glassy single-sized (about 2mm) particles. The main use for copper slag In Australia is in grit blasting, due to its sizing and strength characteristics.[ This from Australia]----------------

· The study conducted by CRRI shows that use of copper slag in concrete

have no adverse effect on its strength (Fig.) and a blend of copper slag and

fine sand with slag up to 40 percent can be used as fine aggregate in pavement quality concrete as well as in dry lean concrete.[ This from Indian Road research]----

· Mixed with water, most slags do not generate hydration products. An activator

must be added to trigger their reactivity; activators may be bases such as sodium or

calcium hydroxide4. This is why slags react when added to portland cement, since its

hydration produces calcium hydroxide (in this case named portlandite) as one of the

hydration products.

Using calcium hydroxide it may be possible to experimentally model the reaction

which occurs within the cement paste between portlandite and copper slag. The evolution

of the microstructure with time of calcium hydroxide/slag pastes have been studied. Then

pastes of cement mixed with slag were prepared to observe the modification of the

hydration of portland cement due to the presence of copper slag.[This from Canada]--------------