calcining

The calcining and coking kilns are rare surviving examples of the thousands of kilns once found throughout Britain.

It should be noted that when the total carbon footprint of the alkali required to form geopolymer cement is considered, including the calcining of limestone as an intermediate to the formation of alkali, the net reduction in total CO emissions may be negligible.

Cement cannot be produced without carbon dioxide release, even an all electric method using a plasma arc torch to perform the calcining of the limestone feed would have carbon dioxide emissions 60% those currently achieved even if the electricity is derived from a low carbon source such as nuclear power or hydro.