【作者】 高红梅；

【导师】 王明学；

【作者基本信息】 华中农业大学 ， 水生生物学， 2005， 硕士

【摘要】 沼山沸石是湖北省新近开发出来的一种天然斜发沸石,其研究工作刚刚开始。本课题是在实验室条件下进行的,重点研究沼山沸石吸附水中氨氮的基本性能,以及不同试验条件对该沸石去氨氮效果的影响;根据沼山沸石的吸附性能,制备改性沸石（主要是利用加热、酸、碱、盐改性）,研究合适的改性条件以及改性沸石去氨氮的效果;同时根据沼山沸石吸附微生物的特性,分别用来固定硝化细菌和光合细菌,制成生物沸石,研究生物沸石去除氨氮的效果及相关因素对氨氮去除效果的影响,试验结果如下: 沼山沸石的阳离子（NH₄⁺）交换容量为4.068mg/g,其对氨氮的吸附过程很好的符合Freundlich吸附等温式。沼山沸石吸附氨氮后会发生解吸,用1000mg/L的NaCl溶液洗脱吸附平衡后的沼山沸石,解吸率达到42.4%,并且解吸率随着沸石吸附量的增大而增大。 沸石的用量、沸石和氨氮接触时间、溶液pH值、环境温度都会对沼山沸石去氨氮的效果产生很大的影响。在氨氮含量一定的溶液中,开始时氨氮去除率随沼山沸石投加量的增加而增加,当氨氮去除率增大到一定的时候,再增加沸石用量,氨氮去除率增加有限;沼山沸石吸附水中氨氮的速度较快,约20min即可达到平衡,并且该平衡持续时间较长（2h）;溶液pH值对氨氮去除率有较大影响,pH<7时,氨氮去除率随pH值的升高而增加,pH>7时,氨氮去除率随pH的升高而降低,pH值=6-8时,氨氮去除率较高;温度越高,氨氮吸附量越大,但是温度大于25℃时,升温对氨氮吸附效果的改善不大,低温（小于25℃）的影响相对较大。 加热改性的适宜温度为450℃,适宜时间为2.5h,此时改性沸石的氨氮去除率比未改性时提高了12.36%;酸（H₂SO₄、HCl和HNO₃）改性沸石的氨氮去除率比未改性时略有提高,说明沼山沸石不适合用酸来改性;低浓度NaOH溶液（小于0.75mol/L）有一定的改性效果,但所需洗涤时间较酸和盐长,操作麻烦;NaCl改性能明显提高沸石对氨氮的去除率,且改性沼山沸石对氨氮的吸附性能比未改性时要提高10倍以上。综合考虑技术经济等因素的影响,认为适宜改性的NaCl浓度为2.0mol/L,改性时间4h,并且该浓度下适宜改性的沸石质量与NaCl溶液体积比为0.25g/ml。更多还原

【Abstract】 Zhaoshan zeolite is a kind of clinoptilolite newly exploited in Hubei, the study on the zeolite is at an eary stage. This paper mainly studied three aspects about Zhaoshan zeolite: first, the basic performance of ammonia-nitrogen absorption and influence factors on the effect of ammonia-nitrogen removal by Zhaoshan zeolite. Second, the choices of suitable method to make zeolite modified and the effect of ammonia-nitrogen removal by the modified zeolite, Third, immobilizing nitrobacteria and PSB respectively using Zhaoshan zeolite as bio-zeolites and influence factors on the effect of ammonia-nitrogen removal by the bio-zeolite. The experiment results were as follows:Results showed that the cation （NH₄⁺） exchange capacity of the Zhaoshan zeolite was 4.068mg/g, the process of ammonia-nitrogen was fit for the formula of Freundlich. The desorption efficiency was 42.4% after soaked by 1000mg/L NaCl and the desorption efficiency was increasing with the increasing of ammonia-nitrogen absorption.The dosage, treating time, pH and temperature had great influences on the ammonia-nitrogen adsorption. The ammonia-nitrogen removal rate was increasing with the increasing dosage, treating time, pH, temperature in general. In the experiment, treating 20min, pH=6-8, could get a good effect. Increasing temperature could promote the effect only a little（t>25℃）.Heating 2.5h at 450℃was the optimum condition for the zeolite modified by heating, at this time the ammonia-nitrogen removal rate was much higher by 12.36% than the Zhaoshan zeolite’s; The zeolites modified by H₂SO₄, HCl and HNO₃ were not fit for ammonia-nitrogen removal because of bad effect; The zeolite modified by NaOH of lower concentration （<0.75mol/L） had some good effect, but the process to get the modified zeolite was very difficult with costing great time; The zeolite modified by NaCl had remarkable effect on ammonia-nitrogen removal, the adsorption capacity ofammonia-nitrogen was ten times better than the natural zeolite, and treating 4h at 2.0mol/L of NaCl was the optimum condition for the zeolite modified by NaCl thinking of the factor of technique and economy, and the optimum ratio of （zeolite weight）/（solution volume） was 0.25g/ml.The effect and endurance of zeolite immobilized by nitrobacteria was better than the effect of single Zhaoshan zeolite and single nitrobacteria on ammonia-nitrogen removal. Inoculation dosage, pH, temperature had great influences on ammonia-nitrogen removal. It required a weak alkaline pH and 32 °C. The ammonia-nitrogen removal rate was increasing with the increasing of nitrobacteria inoculation dosage pH and temperature, but would decrease with a superfluous inoculation dosage and pH>8.5, temperature over 32 °C. Moreover lower temperature（<20°C） would be a limited factor for ammonia-niatrogen removal.The effect of zeolite immobilized by PSB was better than the effect of single Zhaoshan zeolite and single PSB on ammonia-nitrogen removal. This showed that the immobiliztion could preserve the avtivity of PSB very well and exert the function of bio-chemical combination on ammonia-nitrogen removal. The ammonia-nitrogen removal rate was increasing with the increasing of PSB inoculation dosage and pH and temperature, but would decrease with a superfluous inoculation dosage, pH>8and temperature over 30 °C.更多还原