Early-warning is an effective way to control mud expansion in sewage treatment plants with A/O technology. In the research, warning indices and technology of active mud were explored and it is concluded that bacteria ...Early-warning is an effective way to control mud expansion in sewage treatment plants with A/O technology. In the research, warning indices and technology of active mud were explored and it is concluded that bacteria growth in mud can be obtained by observation of mud appearance and microorganism variety, and measurement of the number of filamentous bacteria, water quality, mud load and age, dissolved oxygen, temperature and pH. Furthermore, filamentous bacteria in mud can be researched through fluorescence in situ hybridization, PCR-temperature denaturing gradient gel electrophoresis and PCR-single-stranded conformation polymorphism in order to determine the characters and states of active mud to achieve early warning of mud expansion.展开更多
[Objective] This study aimed to make use of the limited filamentous sludge bulking characteristics to purify water quality and save energy. [Method] The effects of dissolved oxygen （DO） on sludge bulking were explor...[Objective] This study aimed to make use of the limited filamentous sludge bulking characteristics to purify water quality and save energy. [Method] The effects of dissolved oxygen （DO） on sludge bulking were explored by changing the DO con- centration in the aerobiotic pool of NO system from the low load （0.25 kg COD/（kg MLSS.d）） and the medium to high load （0.55 kgCOD/（kg MLSSod））. [Result] In the NO activated sludge system, when the sludge load was 0.25 kg COD/（kg MLSS.d）, DO=1.5 mg/L, the sludge index was at around 250, while when the sludge load- ing was 0.55 kg COD/（kg MLSS.d）, DO=1.5 mg/L, the sludge index was close to 300, occurring the limited filamentous bulking. The bulked sludge still showed high removal rates to COD, SS, nitrogen and phosphorus. [Conclusion] It could improve the oxygen transfer rate and reduce the aeration rate at low DO conditions to achieve energy-saving.展开更多
基金Supported by National Natural Science Foundation of China(51208068)~~
文摘Early-warning is an effective way to control mud expansion in sewage treatment plants with A/O technology. In the research, warning indices and technology of active mud were explored and it is concluded that bacteria growth in mud can be obtained by observation of mud appearance and microorganism variety, and measurement of the number of filamentous bacteria, water quality, mud load and age, dissolved oxygen, temperature and pH. Furthermore, filamentous bacteria in mud can be researched through fluorescence in situ hybridization, PCR-temperature denaturing gradient gel electrophoresis and PCR-single-stranded conformation polymorphism in order to determine the characters and states of active mud to achieve early warning of mud expansion.
基金Supported by the National Natural Science Foundation of China(51208068)~~
文摘[Objective] This study aimed to make use of the limited filamentous sludge bulking characteristics to purify water quality and save energy. [Method] The effects of dissolved oxygen （DO） on sludge bulking were explored by changing the DO con- centration in the aerobiotic pool of NO system from the low load （0.25 kg COD/（kg MLSS.d）） and the medium to high load （0.55 kgCOD/（kg MLSSod））. [Result] In the NO activated sludge system, when the sludge load was 0.25 kg COD/（kg MLSS.d）, DO=1.5 mg/L, the sludge index was at around 250, while when the sludge load- ing was 0.55 kg COD/（kg MLSS.d）, DO=1.5 mg/L, the sludge index was close to 300, occurring the limited filamentous bulking. The bulked sludge still showed high removal rates to COD, SS, nitrogen and phosphorus. [Conclusion] It could improve the oxygen transfer rate and reduce the aeration rate at low DO conditions to achieve energy-saving.
