Study On The Treatment Of Ammonia-nitrogen From Wastewater With Modified Zeolite

With the rapid growth of the economy, industry and agriculture, rapid population growth accelerates ammonia wastewater discharge. It wildly step over the self-purification capacity of the environment, so it exacerbated by eutrophication or "red tide", even "bloom" phenomenon. These severe cases may lead to massive deaths of aquatic organisms and bring about huge economic losses.In recent decades, researchers carried out a large number of ammonia wastewater treatment methods so as to lessen theammonia wastewater impact on environment. Wherein the zeolite acts as an inorganic mineral, researchers use it to remove the ammonia water to reduce cost. Its simple process operation, multiple recycling and other advantages draw a lot of attention. But there has a problem: natural zeolite adsorption amount of ammonia nitrogen is limited, as a result it can not fully play the full adsorption ability of ammonia. So how to find a method of increasing the amount of zeolite adsorption of ammonia treatment is necessary. Its Internal structure has a large pore zeolite, cavities, metal cation which shows that it has good adsorption and ion exchange properties. Therefore physically or chemically modification with natural zeolite to raise the amount of adsorbed ammonia is practicable.Firstly, the study adopt hydrochloric acid modified, sodium hydroxide modified, sodium chloride modified, roasting modified, modified and combined with microwave to improve natural zeolite’s adsorptive power. The results show that the union modified zeolite’s effect achieves the best. Experimental results show that 4g natural zeolite, 90g/L NaCl solution 50 ml, at 50% after the microwave power modified 5min can get the best amount of modified zeolite adsorption of ammonia. By X-ray diffraction, specific surface area and pore size tester, field emission electron microscopy and X-ray surface sweep spectrometer natural zeolite and modified zeolite characterization, experimental data and maps show: Combine modified zeolite has the largest surface area, and in the process of course there has some new substances that contain sodium.Secondly, we use combined modified zeolite as adsorbent to conduct static adsorption experiments with ammonia wastewater. When the modified zeolite dosage is 1.0g, in 135r/min, stirring at 20℃ 1h, 50 ml 100mg/L ammonia wastewater, the removal rate is 85%, ammonia adsorption is 4.25mg/g; when the reaction temperature is 25℃, adding 1.0g modified zeolite and stirred at 135r/min 1h, 50 ml 100mg/L of ammonia wastewater, the removal efficiency is 93%, the amount of ammonia adsorption is 4.65mg/g; when reaction time is 140 min, the dosage 1.0g modified zeolite, 135r/min, at 25℃, 50 ml 100mg/L ammonia wastewater, the removal rate is 92%, the amount of ammonia adsorption is 4.6mg/g; when the wastewater pH is 7, adding 1.0g modified zeolite, in 135r/min, stirring at 25℃ 1h, 50 ml 100mg/L ammonia wastewater, its removal rate is 86%, ammonia adsorption is 4.3mg/g; when the speed is 175r/min, casting 1.0g modified zeolite, at 25℃, pH=7, stirring 1h, 50 ml 100mg/L ammonia wastewater, the removal rate is 88%, the amount of ammonia adsorption is 4.4mg/g; when the dosage 1.0g modified zeolite, 135r/min, 25℃, pH=7 when stirred 1h, 50 ml, the initial ammonia concentration was 50mg/L, 200mg/L wastewater ammonia removal rate are 97%, 65%, ammonia adsorption capacity are 2.4mg/g, 6.5mg/g. Then orthogonal design experiments to determine the influence of five factors of ammonia adsorption joint modified zeolite order: initial concentration of ammonia nitrogen wastewater > pH > modified zeolite dosage > reaction temperature > speed.