Assessing the impact of Solids Retention Time (SRT) on the secondary clarifier capacity using the State Point Analysis

作者：James, Oleyiblo Oloche^*; Cao, Jia-Shun; Kabo-Bah, Amos T.; Wang, Gan

来源：KSCE Journal of Civil Engineering, 2015, 19(5): 1265-1270.

DOI：10.1007/s12205-014-0106-1

• activated sludge
• oxidation ditch
• secondary clarifier
• SPA
• SRT

The State Point Analysis (SPA) tool implemented in BioWin software was used to study the impact of Solids Retention Time (SRT) on the secondary clarifier as it relate to effluent quality in a full-scale treatment plant. SRT is the operating parameter which replaces loading factor as the key design parameter in the activated sludge design. It influences a number of factors, such as; growth rate of microorganisms, nitrification, biomass stabilization, degradation of slowly biodegradable organics, selection of microbial composition of the mixed liquor and its settling and treatment characteristics. SRT is the most difficult parameter to manipulate, its control is paramount to ensure effective waste water treatment. Studies have shown best operating SRT's, nevertheless, the clarifier working conditions in those studies were not considered. SPA is a practical tool developed for the purposes of assessing clarifier performance under different operating scenarios. This study shows the usefulness of SPA in determining optimum operating SRT while maintaining clarification and thickening without compromising clarifier operation. The SPA results revealed that the clarifier is overloaded at the present operating SRT (16 days). However, it was found that the treatment plant performs better at 12 days SRT without violating effluent concentrations and without being critically loaded.

• 出版日期2015-7
• 单位河海大学