| Fly ash, largely produced from thermal power generation, causes many serious environmental problems throughout the world nowdays. Much attention has been paid on the utilization of it both in public and industry. In this paper, it has been conducted that fly ash, collected from Dalian Beihai thermal plant, adsorbs the pollutants of cookery waste water, collected from the effluent of Beigang Coke Plant, in which the water has been treated by the processes of pretreatment, A/O biological treatment. The chemical composition, mineral components, the surface texture and N2 gas adsorption performance of the fly ash were analyzed by modern analytical instruments. The adsorption experiments of removing organic pollutants from coking wastewater by fly ash were performed via the batch technique, and fly ash saturated with organic pollutants was regenerated by Fenton reagent experimentally.By the X-ray fluorescence, it was discovered that silica, alumina and iron oxides are the primary components of fly ash, and with a small amount of calcium, magnesium, potassium, sodium, phosphorus and titanium oxides. The content of the three primary components is more than 90%. The X-ray diffraction pattern of the fly ash showed that the main mineral crystals are quartz, mullite and magnetite, and there are a large amount of glassy particles in the fly ash.The SEM showed that the fly ash is made up of glassy particles, unburned carbon particles and spherical particles. After regenenation of Fenton reagent oxidation, a large amount of small pores has been yieled, and the number of spherical particles increased greatly. The microstructure of fly ash is becoming from irregular into reticular, making the specific surface larger, as well as a higher adsorption capacity.The adsorption experiments of N2 by the fly ash have taken out to determin the physical properties. The results are as follows:BET method surface area, BJH method cumulative adsorption surface area, BJH method cumulative adsorption pore volume, BET method average pore diameter, BJH method adsorption pore dameter and BJH method desorption pore diameter are 6.97 m2/g,5.505m2/g,0.0128 cm3/g,7.943nm,1.732nm and 1.386nm respectively.The adsorption and regeneration experiments had conducted respectively. Results show that, in the range of 283-313K, the equilibrium adsorption is attained by 60min, the equilibrium adsorption capacity decrease with increasing temperature, and pH has little effect on the adsorption. Equilibrium adsorption data satisfied both Freundlich and Langmuir isotherms. The rate of adsorption follows first order kinetics before attaining equilibrium. A significant effect of Fenton regeneration was obtained. The regeneration efficiency was up to 136% at 30℃by Fenton oxidation at pH 5, with molar ration of Fe(Ⅱ) to H2O2 for 1 to 3, and mass ration of H2O2 to COD for 2 to 3 at 10min.Above all, fly ash has a good adsorption capacity for removal of organic pollutants in coking wastewater. The adsorption capacity is further improved by Fenton reagent oxidation, so it can be recycled and resused many times. That is to say, fly ash does not need to change frequently in wastewater treatment and there will have no sludge treatment. Fly ash is expected to be large-scale application in wastewater treatment area.
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