改性氧化铁沸石用于生物慢滤柱去除窖水中氨氮的实验研究

STUDY ON THE PERFORMANCE OF IRON-OXIDE-COATED ZEOLITES USED IN SLOW FILTERING COLUMN FOR AMMONIA NITROGEN REMOVAL IN CELLAR WATER

对比分析改性氧化铁沸石和普通沸石用于生物慢滤柱中的挂膜情况和对氨氮的去除效果,研究滤层厚度、滤速、水温、进水氨氮和CODMn负荷对氨氮去除率的影响。结果表明,沸石经改性后改善了表面性能,装填改性沸石的慢滤柱挂膜更快,对氨氮的去除率更高。慢滤柱对氨氮的平均去除率可以达到85%以上。随着滤层厚度增加氨氮去除率升高;滤速越大去除效果越差;氨氮去除率同水温呈正相关,与进水CODMn负荷呈负相关;进水氨氮负荷较低时,去除率随负荷加大而升高,进水氨氮负荷高于0.08mg/(L·h)时,去除率基本无变化。

Biology slow filtering techniques had the advantages of convenient operation and simple management, and they were applicable to cellar water in the towns in Northwest China. The contrastive analysis was made with iron-oxide-coated zeolites and common zeolites on the biofilm culturing, and the ammonia nitrogen removal effect in the slow filtering columns, the impacts of thickness of filter bed, filtration rate, water temperature, infiuent ammonia nitrogen loading and CODw loading on the ammonia nitrogen removal rate were analyzed. The results showed that the surface morphology of the zeolites improved after modification. The slow filtering column filled with modified zeolites had the faster speed for membrane forming and higher ammonia nitrogen removal rate. The average ammonia nitrogen removal rate of both the slow filtering columns could reach over 85%. The ammonia nitrogen removal rate was higher with the thickness of filter bed increased. The device had low removal rate under high filtration rate. There was a positive correlation between the ammonia nitrogen removal rate and water temperature, and a negative correlation between the removal rate and influent COD~ loading. When the influent ammonia nitrogen loading was low, the ammonia nitrogen removal rate increased with the ammonia nitrogen loading increased. When the influent ammonia nitrogen loading was over 0.08 mg/（L · h）, the removal rate had no change.