Research On The Medical-stone Used To Optimize Drinking Water

With the improvement of living standards, people have put forward higher requirements for drinking water, not only hope that the water does not contain harmful substances, but also hope that the water is rich in composition that benefit to the human body. The natural Medical-stone is directly used for tap water treatment, changes of Pb, Cu, Mn and Zn ions in the water after treated by Medical-stone were studied by static experiments, single factor experiment was used to investigate the effect of the particle size, dosage of Medical-stone and time on the treatment result. It was shown that with the decreasing of the grain size and the increasing of dosage the optimization function of Medical-stone was enhanced. In a certain period of time, the optimization effect of Medical-stone on water quality is improved with the extension of time. Useing 40-60 mesh Medical-stone, the ratio of liquid to solid choose 5:1, processing for 1h is suitable.Under the suitable condition, the Medical-stone modified by acid, heat or both of them was used to treat drinking water. The impacts of the acid concentration, temperature and conditions of composite modification on the dissolution and absorption of Medical-stone was researched. Results show that both heat modification and acid modification can promote ion-exchange properties of the Medical-stone. Acid modification first is better than thermal modification first. Medical-stone modified by 1.5mol/L hydrochloric acid firstly, and then modified at 400 ℃ is suitable. Dissolution and absorption break through curve of Medical-stone modified under this condition has been determined. Effective time and equilibrium time has been researched.Studied the dissolution kinetics of Cu, Mn and Zn in the Medical-stone that modified under suitable conditions and kinetic of adsorbing Pb. The relationship between the dissolution rate constant and temperature of Cu, Mn and Zn is kcu=0.54965×e-9.8836/RT, kMn=0.0818×e-3.9/RT, kZn=0.1569×e-6.044/RT. The relationship between adsorption rate constant and temperature of Pb is ΣPb=1.554×e-11.165/RT.