Preparation Of Modified Ceramsite And Experiment Research In Enhanced Filtration

Alongside the sources of drinking water are polluted increasingly, traditional water treatment technology can hardly reach the national hygiene standard of drinking water,so it is necessary to develop new water treatment technology.Coating of iron-oxide can improve the surface characters of original filter media,and will then ehance the ability of filter media to remove contaminent such as organic matter.This experiment uses a kind of ceramsite which is produced by a filter material factory of Pingxiang as the carrier,choosing FeCl₃ as the modifying agent,we assume the way of high-temperature preparation to modify ceramisite preparation. After confirming modifying conditions, density of modifying agent, roasting temperature, roasting time and pH value, we discover a kind of ceramsite to reach the highest removing rate of organic matter, which contains FeCl₃ with the density of 2mol/L, roasting temperature at 650 centigrade, roasting time of 3 hours as well as without sodium hydroxide.Surface area after modified is 2.06 times as large as that of plain ceramisite;pH value at zero point of charge on oxide is higer than 7.Static absorbing experiment shows that the absorbing capacity of organic matter by modified ceramsite is larger than unmodified ceramsite and quartz,the adsorbing of organic matter agree with Langmuir model;but the effect of removing ammonia-nitrogen is less.Filter experiment with model filter pillar indicates that the filter period of modified ceramsite is longer than unmodified ceramsite and quartz, while the increasing rate of water head loss is smaller, morever,the water productivity within a period and the capacity of retaining impurities are higher than the later ones.The effect of removing organic matter with the slightly acid condition is best. With low density of intaking water, the average rate of removing organic matter reaches high. With the slower filter speed , the time that organic matter touches the filter bed longer, the removing effect is better.