Green inhibitors reduce unwanted calcium carbonate precipitation: Implications for technical settings.

Mineral scale deposits in water drainage and supply systems are a common and challenging issue, especially by clogging the water flow. The removal of such unwanted deposits is cost intensive arguing for case-specific and sustainable prevention strategies. In the present study, a novel on-site approach to prevent calcium carbonate (CaCO) scale formation was assessed in two road tunnel drainages: Application of the eco-friendly green inhibitor polyaspartate (PASP) caused (i) a significant inhibition of CaCO precipitation, (ii) a more porous or even unconsolidated consistence of the deposits, and (iii) a shift from calcite to the metastable aragonite and vaterite polymorphs.

Scale deposits in tunnel drainage systems - A study on fabrics and formation mechanisms.

Rapid deposition of chemical sediments, particularly calcium carbonate, is a widespread phenomenon in tunnel constructions, which can significantly disturb water draining. The removal of the scale deposits in the drainage setting is labor and cost intensive. Prediction or prevention of these unwanted scale deposits are challenging and require detailed knowledge on their site-specific source, formation mechanisms and environmental dependencies.