| The eutrophication situation of lakes is very severe in recent years. And the main reason which leads to the result is over surplus nitrogen and phosphorus into the water body. So many documents make clear that phosphorus quantity is the key role. Chemical and biological techniques play important role. However, the chemical methods consume great amount of medical flocculants and coagulating, and generate huge volumes of sludge. To the biological methods, there are operated badly, and at the same time temperature and pH vale of influence play a great impact on removal ratio. Absorption takes up with the deficiency of chemical and biological measures. Adsorbents with high specific-surface area separate phosphate from sewage by surface adsorption, ion exchange and precipitation, and farther phosphate can reclaim as resource.The thesis researches on the eutrophied water body, and uses zeolite which has natural selection of cheap, large and roughness surface area as raw material. Through experiment, preparing a new type of adsorbent properties and effects of removal, regeneration methods and conditions, different solid-liquid ratio, different size, different pHand temperature and so on. 2% of NaOH mixes with zeolite at solid-liquid ratio of 1:10 in 12h. Then washing and drying zeolite. Zeolite mixes with AlCl3, MgCl2 and water at mass ratio of 3:1:3:20. At pH=7,the mixture immerse in 10h.After washing and drying, makes the zeolite calcine in the muffle furnace at 350℃in 1h.The main conclusions have been summarized as follows:1. At the optimum conditions obtained for the modified zeolite by static and dynamic experiments to study the absorption properties. In the static experiments, with the increase of the immersion time, the adsorption capacity of absorbent will increase. When the immersion time reaches to 9h, the adsorption capacity will not change. With the crease of the adsorbent dosage, the removal rate will increase and the adsorption capacity will decrease. When the solid-liquid ratio is 1:200, the adsorbent will be the saturated adsorption state. Through the static test can see that when the concentration of phosphate solution increased continuously, the saturation adsorption capacity rises continuously as well. The adsorption process of phosphate on the modified zeolite fits the Fredulich-type adsorption isothermal models in the range of experimental concentrations of 5-500mg/L.2. With the crease of pH, the adsorption capacity of modified zeolite will increase. When pH=5, adsorption capacity was maximum. Then, adsorption capacity decreases with the increasing pH. At the same time, as the temperature increased, the adsorption capacity of the modified zeolite decreased, but little change. So the modified zeolite could be used for general treatment of phosphorus wastewater.3. In the dynamic experiment, compounding 50mg/L phosphorus wastewater simulating the water sample to be processed, choose a 30mm diameter glass column, and load the adsorbent to the column in 38.8cm high. The flow rate was fixed at 4.6ml/min, settling time was 60min, this adsorption post handled the water amount of 12546ml, and the average adsorption capacity is 2.89mg/g.5. When the water reached the phosphorus concentration of 1mg/L, it had already reached the penetration point, the modified zeolite could no longer treat anything. This experiment used static methods to study regeneration. The optimum regeneration condition: Zeolite was mixed with NaOH, Na2CO3 and water at mass ratio of 25:12:12:200 for 6h. The regeneration ability of modified zeolite is very good. The renewable capacity to maintain about 99.62%.This study is to determine the zeolite as the carrier of preparation of a new type of adsorbents, process simple, low-cost, easy recovery, no secondary pollution to solve the eutrophied water body and the high phosphate water is of great significance.
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