| The diatomite is the biologic quartzite which is made up of the diatoms and the siliceous which remains of the other microorganisms. It owns a huge ratio surface area and strong surface adsorption. As a new type of natural micro porous material, the diatomite has extensive sources, good effect of treating sewage and uncomplicated equipment for subsequent sludge disposal, so it's application prospect is broad and bright.This paper makes a study of the preparation process of modified diatomite, and the adsorbing property of the new modified diatomite to Fe3+ under different conditions in the process. Then making a preliminary conclusion-which is the optimum modified conditions of diatomite. According to the adsorbing experiment of the modified diatomite to Fe3+in the wastewater(man made), the passage explores the effect of the amount of modified diatomite, reaction time, adsorption temperature, solution pH, Fe3+ ions initial concentration on the adsorption effect, and then concludes the best condition. Finally, using a combined process which is formed by the previous research result to treat wastewater. The main findings are as follows:1) During the modified Preparation of modified diatomite, the main factors affecting the process are different ratios, different baking temperature and time. The ideal conditions are:the ratio of the proportion of diatoms is 80%, baking temperature is 500℃, baking time is 90min.2) In accordance with the optimum conditions for the preparation process, the new form of modified diatomite can be described as follows:it has certain intensity, its distribution is regular, the particle size is about 5mm, the color is pale yellow small round particles.3) Within a certain range, the modified diatomite to Fe3+ ions with soil volume, adsorption time, adsorption temperature, pH value increases, the initial concentration of solution with the absorption increases, the removal rate of Fe3+ increases with the increase of soil volume, adsorption time, adsorption temperature and pH value, decreases with the increase of adsorbent initiative concentration. 4) According to the orthogonal experiment, the paper studies the combined effects of the amount of modified diatomite, pH, temperature and Fe3+ ions initial concentration to the adsorption of modified diatomite to Fe3+ions. The effect result is list from main to the second order:the amount of modified diatomite> Fe3+ ions initial concentration> pH value> temperature. The best adsorption conditions are as follows:the amount of modified diatomite is 10g/L, pH value is 4.0, temperature is 40℃and the Fe3+ ions initial concentration is for 50mg/L.Under the best condition, the paper researches the adsorption experiment of modified diatomite to Fe3+ which concentration is 100mg/L. The results show that the removal efficiency of the original soil to Fe3+ ions is only 86.73%, while the removal efficiency of the modified diatomite to Fe3+ ions can up to 99.51%, the efficiency increases 12.78%.5) The paper make a research of pilot scale with the use of modified diatomite. The wastewater is from Zhuzhou Yongli Chemical Co, Ltd, and the modified diatomite is used as a water treatment agent. The results showes that the modified diatomite is only suitable for the treatment of the wastewater, the concentration of the heavy metal in which is low, and it should not deal directly with high concentrations of heavy metals in the acidic waste water. When pH value has been adjusted, modified diatomite can remove some contaminants, the treatment systems can be remove As, Pb, Cu, Cd, SS, Cr and Fe3+ ions efficiently, and the quality of discharge is good. Because of the combined process of treatment, some of the total removal of contaminants has been close to 99%, and compliance rate of all pollutants are reach to 98%.The above research results is a certain instruction to the treatment of ferri industrial wastewater which is with the help of modified diatomite, and provides a theory basis and a technical support for the application of modified diatomite.
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