| 用于地下水原位生物脱氮的缓释碳源材料性能研究 |
| 摘要点击 4303 全文点击 2446 修订日期：2007-10-31 |
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| 中文关键词 地下水 原位脱氮 缓释碳源材料 α-淀粉酶 |
| 英文关键词 groundwater in-situ nitrate removal carbon source materials α-amylase |
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| 中文摘要 |
| 针对地下水原位生物脱氮时缺乏电子供体（碳源）导致反硝化受抑的问题，以淀粉为碳源原料，聚乙烯醇（PVA）为载体，α-淀粉酶为添加剂，采用共混技术制备GPVAS和GEPVAS两类反硝化原位反应格栅（PRB）缓释有机碳源（SOC）材料.扫描电镜和静态实验研究结果表明，材料内部形成淀粉分子填充的PVA网状骨架结构，释碳符合二级动力学过程，动力学参数平衡浓度（cm）和释放速率系数（k）可作为评价缓释碳源释碳能力的核心指标.材料配比和α-淀粉酶含量对材料性能影响显著，当淀粉/PVA＝40/60时，材料 cm和k值最低；cm值随酶含量增加显著升高，k值随酶含量增加先升高后降低，表明碳源释放速率可通过组分配比和酶添加剂含量进行有效控制，以适应不同地下水环境和硝酸盐污染程度，提高原位脱氮效率. |
| 英文摘要 |
| As lack of electron donor (carbon source) is a key problem of in-situ denitrification in groundwater, slow-release organic carbon-source (SOC) materials were produced as appropriate electron donor in denitrification PRB. GPVAS and GEPVAS series were manufactured by blending starch and PVA together, with α-amylase as the additive, and their performance was detected through SEM and static batch experiments. The results showed that PVA fromed the framework filling with starch molecule, and the carbon releasing process followed the law of second order kinetics. Equilibrium concentration of COD (cm) and release rate coefficient (k) were key factors of kinetics evaluation. Both cm and k of GPVAS-40 were the lowest. The influence of α-amylase to the performance of SOC materials was remarkable. The cm values would ascend rapidly with augmenting of α-amylase content, while the releasing speed rose when amylase activity was lower than 0.03 Ｕ/g and then decreased. Consequently, the releasing process was controllable through changing the content of starch and activity of α-amylase to meet needs of different situations and pollution of groundwater and improve the effect of in-situ nitrate removal. |
