低温下磁加载强化纯膜MBBR工艺除磷效果OA北大核心CSTPCD
Phosphorus removal effect enhanced by magnetic seeds loading in pure membrane MBBR process at low temperature
在低温条件下向纯膜MBBR工艺出水投加铁盐除磷时,由于生成的微细含磷絮体难以沉淀而导致磷去除率偏低.该研究以氯化铁为混凝剂,在10℃下考察了不同粒径磁粉的强化除磷效果.结果表明,投加18和58 μm的磁粉分别比不投加磁种时的TP去除率提高了 8.52%和5.12%,其原因主要在于微细含磷絮体得到了强化去除.比较投加5种粒径磁粉生成絮体的分形维数,发现磁粉粒径在18~58μm时,粒径越小生成絮体的分形维数值越大,即絮体密实度越高;而当磁种粒径超过58µm后分形维数值迅速降低,即絮体的密实度变差.絮体抗剪切能力测试结果表明,投加18 pm磁粉形成的含磷絮体强度优于58 µm磁种,且前者的污泥沉降性能也明显好于后者.以上结果表明,低温条件下投加微小粒径磁粉有助于形成以磁粉为核心的密实絮体,絮体良好的沉降性能和对细微含磷颗粒的捕集能力提高了 MBBR工艺磷的去除率.
When iron salts were added to the effluent of pure MBBR process for phosphorus removal at low temperature,the phosphorus removal rate was low due to the poor setting performance of the fine phosphorus-contained flocs.In this study,ferric chloride was taken as coagulant to investigate the enhanced phosphorus removal effect by magnetic seeds with different particle sizes at 10 ℃.The results showed that in comparison with that of FeCl3 coagulation without magnetic powder addition,TP removal rates increased by 8.52%and 5.12%after addition of 18 μm or 58 μm magnetic powder,respectively.This was mainly attributed to the enhanced removal of fine phosphorus-contained flocs.By comparing the fractal dimensions of the flocs formed after adding five kinds of magnetic powders,the smaller the particle size for magnetic powders of 18~58 μm,the larger the fractal dimension,and the more compactness of formed flocs.When the size of magnetic powders exceeded 58 μm,the fractal dimension of formed flocs decreased rapidly,and their compactness became worse.The anti-shear test of flocs showed that the strength and settling ability of phosphorus-contained flocs after addition of 18 μm magnetic powders were better than them after addition of 58 μm magnetic powders.The study confirmed that the addition of magnetic powders with small particle size at low temperature could form the dense flocs with magnetic seeds as the core,and good settling ability and capture ability for fine phosphorus-contained particles of flocs can improve the phosphorus removal rate of the MBBR process.
李金成;焦硕;夏文香;刘杰;董京洲;郑泽坤;王占江
青岛理工大学环境与市政工程学院,青岛 266033
环境科学
磁种MBBR除磷低温絮体结构
magnetic seedsMBBRremoval of phosphoruslow temperaturefloc structure
《环境工程学报》 2024 (010)
2805-2813 / 9
国家自然科学面上基金资助项目(52174336);山东省自然科学面上基金资助项目(ZR2020ME256)
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