Study On Nitrogen And Phosphorus Removal From Tiny Polluted Water Source By Modfied Zeolite

Base on the case that the water eutrophication tendency become more and more serious, many water sources were polluted seriously. A highly effective method with the low-cost to process the polluted water is needed. Processing the water by zeolite, especially the modified zeolite, is the one of proper methods.In this article, different methods were used to modified zeolite,such as: heating ( at different temperature), treating with acid (hydrochloric acid, sulfuric acid or nitric acid), base (sodium hydroxide), salt (ammonium chloride or sodium chloride) with different concentration and for different time. The experiment indicated: for removal of mmonia nitrogen in water modification of zeolite by heating or treating with acids or salts(except odium hydroxide and ammonium chloride) have obvious effect. Compare to the other temperature, hot modified zeolite has better removal effect of 1.8mg/L mmonia nitrogen at temperature of 300-600℃, and the best performance can be abtained at 500℃, the elimination rate reaches as high as 75%. The 0.1mol/L hydrochloric acid modified zeolite is the best method to remove the 1.75mg/L ammonia nitrogen in water, the best quantity is 2.5g/L water samper, the elimination rate reaches 97.1%; The nitric acid modified zeolite to remove the 1.2mg/L ammonia nitrogen when the HNO₃ concentration is 1.0mol/L, the zeolite quantity is 0.8g/L,1.5g/L, 0.25g/L water samper, ammonia nitrogen elimination rate is 99.9%. The sulfuric acid modified zeolite to remove the 1.2mg/L ammonia nitrogen when the H2SO4 density is 0.10mol/L, the modified zeolite quantity is 2.0g/L, ammonia nitrogen elimination rate is 99.4%. The sodium chloride modified zeolite in the sodium to remove 1.75g/L NH₃-N from water when chloride density is 0.4mol/L, the modified time is about 3h, the quality is 5.0g/L, ammonia nitrogen elimination rate is 95.96%. Processing the phosphorus water uses the different mass ratio the aluminum sulfate and the magnesium sulfate to modified zeolite, under the different time, the temperature, the pH value condition carries on the modification, the experiment indicated that the phosphorus polluted water with the sulfuric acid magnalium processing modified zeolite have the good adsorption effect. It is one kind of ideal modified zeolite chemical substance; The modified zeolite quality, the adsorption time, water temperature and so on can affect the modified zeolite's adsorption capacity and the phosphorus elimination rate.Best eliminates the phosphorus condition is: under the room temperature, the modified zeolite quality is 2g/L, the adsorption time is 24h, for 0.5mg/L water samper, the elimination rate reaches 83.7%, adsorption capacity achieved at 5.13μg/g.Finally this article also discussed the method and development of the modified zeolite the nitrogen phosphorus method and the prospects in the micro pollution water sample , discussing the prospect of how to eliminated the phosphorus as soon as to denitrogenation use modified zeolite.