Hydraulic Row Of Gray Scaling Process Dynamics And Scale Inhibition

The dissolving kinetics of free CaO in water and the aerating kinetics of ash-water were studied. And on the basis of that, the feasibility of treating high pH value ash water by being exposed to weather, and the feasibility of nature aerate-scale inhibitor technology were discussed. The results show that the dissolution rate of free CaO was fast. Eighty percent was dissolved in 30 minutes, and the whole process finished approximately in three hours. There was an apparent abduction period about 50-60 minutes in which the scale were informed in the scaling process of CaCO3. The dissolution process and the scale process were effected by various factors, such as water hardness, alkalinity, pH value, ash-water ratio and velocity, etc.The CO2 absorption kinetics of ash water can be deduced from double-films model. It was defined by the results of experiment, and can be used to predict the absorption of CO2 in ash field.Treating ash-water by nature aeration can reduced the pH value, hardness, alkalinity and suspended solid (SS) content under the drainage standard. It was simple, economical and safe.The method of nature aerate-scale inhibitor is feasible for anti-scale. Under the condition of being aerated 20 hours and the dose of PESA was 20 ppm, the scale didn't formed in the ash-transport line and backwater line. The recovery ratio of ash water is nearly 100%.