The micro-mechanism of the scaling of pipelines in the cooling system under deep mine was studied. Firstly

the composition and content of the ions in the mining water were determined by the full analysis of water quality

and then the chemical model and mathematical model were built

finally

the adsorption of scaling ions on iron surface was calculated by using the VASP software based on density functional theory (DFT). The result shows that

① the scaling of the cooling system includes the combination of Ca2+ and CO32+ and the transform of MgCO3

CaSO4 to CaCO3; ② the scaling ions (Ca2+

HCO-

Mg2+ and SO42-) are the main factors leading to the CaCO3 scaling of the cooling system pipelines under deep coal mine and Mg2+ and SO42- could restrain the scaling. The research is of great importance to the understanding of the scaling of the cooling under deep coal mine

pretreatment

and descaling

in order to guarantee the cooling effect and production safety for the geothermal engineering.