# Life Cycle Assessment of Mortars Produced Partially Replacing Cement by Treated Mining Residues
## 3 Results and Discussion  
### Impacts of Raw Materials in Mortar Manufacture  
During mortar production, there are several high energy consuming phases in regard to raw materials acquisition. In this context, the environmental impacts of using conventional materials, as cement, or raw mining residues in mortar manufacture was determined for 1 t of mortars. The environmental pressures based on the typology of the binder used (cement and residue) as function of their content, in each category, are presented in Table 4. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Mortar**} & \multicolumn{2}{c}{**Weight of**} & \multicolumn{5}{c}{**Environmental Impact Category**} \\ \cline{2-9}  & **Cement** & **ADP** & **GWP** & **ODP** & **POCP** & **AP** & **EP** \\ \cline{2-9}  & **Replaced (\%)** & **kg Sb eq.** & **kg CO2 eq.** & **kg CFC-11 eq.** & **kg ethene eq.** & **kg SO2 eq.** & **kg PO4\({}^{-}\) eq.** \\ \hline REF & 0 & \(1.58\times 10^{-4}\) & \(1.08\times 10^{2}\) & \(2.72\times 10^{-7}\) & \(1.76\times 10^{-2}\) & \(1.87\times 10^{-1}\) & \(2.64\times 10^{-2}\) \\ \hline M10 & 10 & \(2.67\times 10^{-4}\) & \(9.73\times 10^{1}\) & \(2.79\times 10^{-7}\) & \(1.64\times 10^{-2}\) & \(1.70\times 10^{-1}\) & \(2.52\times 10^{-2}\) \\ \hline M25 & 25 & \(4.30\times 10^{-4}\) & \(8.15\times 10^{1}\) & \(2.91\times 10^{-7}\) & \(1.46\times 10^{-2}\) & \(1.44\times 10^{-1}\) & \(2.34\times 10^{-2}\) \\ \hline M50 & 50 & \(7.03\times 10^{-4}\) & \(5.51\times 10^{1}\) & \(3.10\times 10^{-7}\) & \(1.17\times 10^{-2}\) & \(1.01\times 10^{-1}\) & \(2.03\times 10^{-2}\) \\ \hline \hline \end{tabular} ADP—Abiotic Depletion Potential; GWP—Global Warming Potential; ODP—Ozone depletion Potential; POCP—Photochemical Ozone Creation Potential; AP—Acidification Potential; and EP—Eutrophication Potential.  
\end{table} 
Table 4: Environmental impacts from the production of 1 t of mortars with cement and raw mining residues as binder constituents. \begin{table}
\begin{tabular}{l c c c c c c c} \hline \hline \multirow{2}{*}{
\begin{tabular}{c} **Mining** \\ **Residues** \\ **Management** \\ \end{tabular} } & \multicolumn{5}{c}{**Environmental Impact Category**} \\ \cline{2-7}  & **ADP** & **GWP** & **ODP** & **POCP** & **AP** & **EP** \\ \cline{2-7}  & **kg Sb eq.** & **kg CO2 eq.** & **kg CFC-11 eq.** & **kg ethene eq.** & **kg SO2 eq.** & **kg PO4\({}^{-}\) eq.** \\ \hline Direct disposal & \(3.35\times 10^{-9.4}\) & \(6.90\times 10^{-1}\) & \(9.80\times 10^{-8}\) & \(1.60\times 10^{-2}\) & \(1.20\times 10^{-2}\) & \(1.10\times 10^{-4}\) & [35] \\ \hline Electrodialytic treatment & \(2.92\times 10^{-10.4}\) & \(7.00\times 10^{-2}\) & \(4.10\times 10^{-9}\) & \(1.50\times 10^{-4}\) & \(2.80\times 10^{-4}\) & \(1.40\times 10^{-5}\) & [35] \\ \hline Thermal treatment & \(3.39\times 10^{-3}\) & \(4.21\times 10^{-1}\) & \(3.98\times 10^{-8}\) & \(5.20\times 10^{-5}\) & \(1.03\times 10^{-3}\) & \(6.47\times 10^{-5}\) & [18] \\ \hline \hline \end{tabular} ADP—Abiotic Depletion Potential; GWP—Global Warming Potential; ODP—Ozone depletion Potential; POCP—Photochemical Ozone Creation Potential; AP—Acidification Potential; and EP—Eutrophication Potential.  
\end{table} 
Table 3: Environmental impacts of the direct disposal, the electrodialytic treatment, and the thermal treatment of 1 kg of mining residues. The major impacts that come from raw materials exploration and uses are reported in the GWP category. The GWP is based on the quantity of greenhouse gases released to the atmosphere, namely CO\({}_{2}\) (that is dominant), methane (CH\({}_{4}\)) and nitrous oxide (N\({}_{2}\)O). Thus, GWP means the total climate change impact of all the greenhouse gases caused by an item as function of the amount of CO\({}_{2}\) that would have the same impact over a 100-year period [38]. From the production of 1 t of mortars, 1.08 \(\times\) 10\({}^{2}\) kg CO\({}_{2}\) eq. are released by the REF, followed by M10, M25, and M50. The highest the mining residues incorporation as binder, the lowest the GWP.