改性粉煤灰在水处理方面的应用

粉煤灰因其具有多孔性、比表面积大、吸附能力强等特性,同时其结构中具有Al2O3、CaO等活性组分,目前在国内已被应用于废水处理方面。通过酸改性、碱改性、盐改性等方法对粉煤灰的表面结构进行装饰,可以增强其吸附性能,提高其对污染物的处理效果;在其表面引入活性基团,还可以拓宽其在污水处理方面的应用范围。在最优试验条件下,改性粉煤灰对印染废水、造纸废水、有机物废水中的色度以及COD的去除率可达85%以上,对废水中重金属离子的去除率可达95%以上,对废水中总磷和氨氮也有明显的去除效果;在藻类废水以及含油废水、生活污水、工业混合废水、矿井水等综合性废水处理方面,改性粉煤灰对其中的多种污染物也有较好的去除作用。同时指出对于改性粉煤灰在水处理方面的应用目前多数局限于试验室研究阶段,提出了可将改性粉煤灰应用于火电厂脱硫废水处理的建议。

Modified Fly Ash Application in Water Treatment

Fly ash has been widely used domestically because of its porosity,large specific surface area,strong adsorptive capacity and its active groups such as Al2O3,CaO etc.By modifying the surface condition of fly ash through methods of acid-modifiation,base-modifiation and salt-modifiation,its adsorptive capacity and treatment efficiency of pollutants can be improved and its range of application in researches on water treatment can be widened.Under the optimal experimental conditions and using modified fly ash,the removal rates of color and COD in printing and dyeing wastewater,papermaking wastewater and organic wastewater are over 85%,and the removal rate of heavy metal ions in wastewater is over 95%,and the removal rates of total phosphorus and ammonia nitrogen can also reach a high level.Modified ash fly can also paly an important part in removing various pollutants in comprehensive wastewater such as algae wastewater,oily wastewater,domestic sewage,industrial wastewater and mine water.It should be declared that until now the applications of modified fly ash in water treatment have mostly been in the stage of experiment,and it should be advised that with all the properties mentioned above,modified fly ash could be used in the treatment of desulfurization wastewater in power plants.