| Activite zeolite capping can not only inhibit the sediment release ammonia tooverlying water body, but also eliminating part of the nitrogen load in the sediments,which is an effective way to control internal pollution. However, the regeneration ofzeolite limits the popularization and application of the technology and how to achieveits regeneration is the key issue. In this study, take four kinds of zeolites for example,investigated the characteristics, mechanism and influencing factors of the regenerationprocess of the activite bacteria which inoculated in zeolite situ regeneration, on thisbasis, the contaminated sediments which isolated from the ancient Canal of Yangzhou isproceeded capping test, obtained the main factors to affect situ regeneration of theactivite zeolite to provide a theoretical basis for the demonstration project along theancient Canal of Yangzhou.The main results are as follows:（1）After vaccination of active bacteria HF3, HF7and WGX10,WGX18,ammonium adsorption regeneration rate of zeolite of up to81%was higher than thecorresponding regeneration rate （62%） under vaccination of indigenous bacteria. Theresults showed that active bacteria HF3, HF7and WGX10, WGX18were suitablevaccination of bacteria source for situ regeneration of zeolite.（2）The internal structure characteristics of zeolite and itself composition are twoinfluence factors of zeolite situ regeneration. The results of scanning electronmicroscopy showed that the surface of zeolite F1and F2attached a large number ofbacteria. However, it is difficult for zeolite F3and F4to attach to zeolite surface. It isverified that the organisms which attached to situ zeolite surface was essential toregeneration of zeolite; of XRD phase analysis showed that: the total cation amount of zeolite itself contain which could exchange the NH4+is impact of zeolite situregeneration, zeolite F1contains a large number of Ca2+、K+、Al3+and Na+, so it isconducive to the regeneration of active bacteria, after activation142day, theregeneration rate up to82.68%; Secondly, zeolite F2, Ca2+, K+and Al3+and Na+cations the total, after activation142day, the regeneration rate up to34.65%; F3zeolite containing of Ca2+, Mg2+,Fe3+, Al3+and other cations, the F4zeolite containingCa2+, total number of cations is rarely,it is not conducive to the zeolite situregeneration,after activation142day, they can’t regeneration.（3） In order to investigate the ability of the activie bacteria in situ regeneration ofzeolite, four kinds of zeolite are proceeded5round capping test. By analyze the data,the results showed that the situ regeneration could make the zeolite F1processexpectancy to5.87years which is the most obvious effect, followed by zeolite F2,process expectancy to2.63years, but can not change the process of the zeolite F3andF4（0.11,0.02years）, after capping F3and F4several months, or even days the systemwere failure（4）Nitrogen load will affect the zeolite situ regeneration process. For zeolite F1,when the ammonia concentration was14.55mg/L, the effective process of zeolite was5.87years, but when the ammonia concentration increased, the effective process ofzeolite F1was reduced to3.33years. Increasing capping density of the zeolite canimprove the rate of regeneration, when capping density were0.21kg/m2,0.63kg/m2,1.05kg/m2,1.46kg/m2,1.89kg/m2, the effective process of zeolite were0.7years,2.14years,2.71years,3.90years, and4.67years, respectively. The regeneration rate ofzeolite increased with increasing zeolite capping density.（5）When the release rate of sediment were varying from0.14mg/（m2.d）,1.61mg/（m2.d）,4.71mg/（m2.d）, to8.51mg/（m2.d） and capping active zeolite （capping desitywas1.46kg/m2）, the eliminating efficiency of TN which capping active zeolite were85.5%,87.82%,89.82%,80.01%, respectively. When the release rate was greater than4.71mg/（m2.d）, the eliminating efficiency of TN decreased significantly.（6）When the active zeolite capping density was different, the eliminating efficiencyof total nitrogen was quiet different. The results showed that when the activite zeolitecapping density were0.21kg/m2,0.63kg/m2,1.05kg/m2,1.46kg/m2,1.88kg/m2,2.30 kg/m2,2.85kg/m2,3.81kg/m2, the eliminating efficiency of total nitrogen were46.57%,64.98%,85.22%,88.87%,88.26%,89.47%,93.12%,91.30%, indicated that the activezeolite of nitrogen loading have a increasing trend with increasing the capping density. |
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