Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
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Như thể hiện trong các chương trước, hiếu khí hạt là một môi trường phù hợp công nghệ sinh học để điều trị nhiều loại nước thải. Tương tự như để kỵ khí hạt, hạt hiếu khí là quá trình tự cố định vi khuẩn có nghĩa là thúc đẩy bởi áp lực chọn lọc trong các lò phản ứng hàng loạt trình tự (SBR) (xem chương 6). | 15 Filamentous Growth in an Aerobic Granular Sludge SBR Yu Liu and Qi-Shan Liu CONTENTS 15.1 Introduction.259 15.2 Causes of Filamentous Growth in the Activated Sludge Process.260 15.2.1 Wastewater Composition.260 15.2.2 Substrate Availability. 260 15.2.3 Dissolved Oxygen Concentration.261 15.2.4 Solids Retention Time SRT .261 15.2.5 Nutrient Deficiency.262 15.2.6 Temperature.262 15.2 Outgrowth of Filamentous Bacteria in Aerobic Granular Sludge SBRs . 262 15.4 Causes of Filamentous Growth in Aerobic Granular Sludge SBRs.267 15.4.1 Type of Substrate.267 15.4.2 Long Solids Retention Time in Aerobic Granular Sludge SBRs.268 15.4.3 Substrate Concentration and Concentration Gradients.270 15.4.4 Dissolved Oxygen Deficiency in Aerobic Granules.272 15.4.5 Nutrient Deficiency in Aerobic Granules.276 15.4.6 Temperature Shift in Aerobic Granular Sludge SBRs.277 15.4.7 Flow Patterns in Aerobic Granular Sludge SBRs.278 15.4.8 Length of Aerobic Feeding.279 15.5 Propagation Patterns of Filamentous Growth in Aerobic Granular Sludge SBRs.280 15.6 Control Strategy for Filamentous Growth.282 15.7 Conclusions.283 References.283 15.1 INTRODUCTION As shown in the preceding chapters aerobic granulation is a tailored environmental biotechnology for treating a wide variety of wastewaters. Similar to anaerobic granulation aerobic granulation is a microbial self-immobilization process that is driven by selection pressures in the sequencing batch reactor SBR see chapter 6 . Experimental evidence shows instability of aerobic granules is the major technical 259 2008 by Taylor Francis Group LLC 260 Wastewater Purification problem encountered in operating an aerobic granular sludge SBR while filamentous growth has been commonly observed in aerobic granular sludge SBRs Tay Liu and Liu 2001 Pan 2003 McSwain Irvine and Wilderer 2004 F. Wang et al. 2004 Schwarzenbeck Borges and Wilderer 2005 . Once filamentous growth dominates the reactor settleability of aerobic granules becomes poor. This .