PRELIMINARY STUDY ON APPLICATION OF SLUDGE DENSIFICATION SYSTEM TECHNOLOGY IN AN INVERTED AAO CONTINUOUS FLOW WASTEWATER TREATMENT PLANT
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摘要: 选取无锡市某污水处理厂(设计规模15万m3/d)进行污泥致密系统处理技术(SDST)工艺优化,在外回流工艺段增设污泥致密模块以实现污泥沉降性能的有效提高。该厂采用倒置AAO工艺(缺氧/厌氧/好氧),一期和二期工程分别作为实验组和对照组,设计规模分别为4万,11万m3/d。致密模块以半覆盖式处理(最大处理量为原设计剩余污泥量的50%),成功运行90 d,一期工程TN去除能力显著提升,出水浓度下降14.7%,由6.32 mg/L下降至5.39 mg/L。启动阶段(1~36 d),一期好氧池污泥沉降速度提升至1.92 m/h,稳定提升阶段(42~90 d),其沉降速度和SVI30分别为(3.62±0.52) m/h和(49.3±5.5) mL/g,而二期分别为(1.93±0.35) m/h和(59.3±5.5) mL/g。污泥致密模块具有稳定的污泥致密作用,致密污泥MLSS为(19.3±2.75) g/L,SVI30仅为(36.7±9.0) mL/g。通过镜检成功观察到致密污泥中含有大量的小型颗粒状絮体,但颗粒化程度有限。研究发现,活性污泥中大量的纤维状和惰性无机物质是影响致密模块稳定运行的重要因素,通过增设螺旋式格栅可以保障致密模块的稳定运行,而无机物质中的砂、铁盐和铝盐等对系统的影响仍需进一步探讨。此外,耦合除砂措施并采用全覆盖式处理以优化改造致密模块是进一步提高致密污泥颗粒化程度的关键。该工程案例系SDST在国内倒置AAO连续流污水处理厂的首次成功应用,将为国内存量污水处理厂的升级改造提供重要思路。
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关键词:
- 污泥致密系统处理技术 /
- 倒置AAO /
- 连续流污水处理工艺 /
- 工艺优化 /
- 沉降性能
Abstract: The sludge densification system technology (SDST) was applied in a wastewater treatment plant (WWTP) for engineering modification, located in Wuxi, with a designed treatment capacity of 150000 m3/d, and a sludge densification module was added in the external reflux process section to effectively improve sludge settling performance. The inverted AAO (anoxic/anaerobic/oxic) process was adopted in the WWTP with the Phase Ⅰ project (40000 m3/d) and Phase Ⅱ project (110000 m3/d), acting as the experimental group and control group, respectively. After the engineering modification, the densification module was successfully operated for 90 days in a half-scale mode, which maximum treatment capacity was 50% of the original design surplus sludge volume. The removal capacity of TN in the Phase Ⅰ project was significantly improved, and the effluent concentration decreased by 14.7% (from 6.32 mg/L to 5.39 mg/L). During the start-up stage (day 1 to 36), the settling rate of aerobic sludge increased to 1.92 m/h. In the stable and lifting stage (day 42 to 90), the settling rate and SVI30 were (3.62±0.52) m/h and (49.3±5.5) mL/g, respectively, while the counterparts of sludge in the Phase Ⅱ project were (1.93±0.35) m/h and (59.3±5.5) mL/g. The densification device had a stable sludge densification effect so that the densified sludge MLSS was (19.3±2.75) g/L, and the SVI30 was only (36.7±9.0) mL/g. Many small granular flocs in densified sludge were successfully observed through microscopic examination, but the degree of granulation was limited. This study found that the massive fibrous and inert inorganic matters in activated sludge were important factors affecting the operation of the densification module, while a spiral grating was added to ensure its operation. Moreover, the effects of these inorganic substances such as sand, iron salt, and aluminum salt on the system still need to be further discussed. In addition, coupling sand removal measures and adopting full coverage treatment to optimize and transform the densification module were the key to further improving the granulation degree of densification sludge. Our team has successfully applied the SDST in an inverted AAO continuous flow WWTP in China for the first time, providing an important method for the upgrading and modification of existing wastewater treatment plants. -
[1] 余诚, 王凯军, 张凯渊, 等. 连续流好氧颗粒污泥技术处理低浓度市政污水的中试研究[J]. 环境工程学报, 2023, 17(3):713-721. [2] STRUBBE L, DIJK E J H V, DEENEKAMP P J M, et al. Oxygen transfer efficiency in an aerobic granular sludge reactor:dynamics and influencing factors of alpha[J]. Chemical Engineering Journal, 2023, 452:139548. [3] van DIJK E J H, PRONK M, van LOOSDRECHT M C M. A settling model for full-scale aerobic granular sludge[J]. Water Research, 2020, 186:116135. [4] WEI S P, STENSEL H D, NGUYEN QUOC B, et al. Flocs in disguise? High granule abundance found in continuous-flow activated sludge treatment plants[J]. Water Research, 2020, 179:115865. [5] 丁健宁, 宫徽, 王顺煜, 等. 水力旋流分离器在水处理领域的应用研究进展[J]. 环境工程, 2021, 39(8):1-6. [6] GONG H, DING J, WANG S, et al. Optimizing granular anammox retention via hydrocycloning during two-stage deammonification of high-solid sludge anaerobic digester supernatant[J]. Science of the Total Environment, 2021, 791:148048. [7] GUO D, JIANG X, GUO M, et al. Role of hydrocyclone separator on the formation and separation of aerobic granular sludge:evaluating granulation efficiency and simulating hydrodynamic behavior[J]. Separation and Purification Technology, 2022, 283:120231. [8] ROCHE C, DONNAZ S, MURTHY S, et al. Biological process architecture in continuous-flow activated sludge by gravimetry:controlling densified biomass form and function in a hybrid granule-floc process at Dijon WRRF, France[J]. Water Environment Research, 2022, 94(1):e1664. [9] 李志华, 赵敏, 贺春博, 等. 旋流选择作用及KLa对污泥颗粒化的影响研究[J]. 环境科学与技术, 2014, 37(3):37-40, 45. [10] REGMI P, STURM B, HIRIPITIYAGE D, et al. Combining continuous flow aerobic granulation using an external selector and carbon-efficient nutrient removal with AvN control in a full-scale simultaneous nitrification-denitrification process[J]. Water Research, 2022, 210:117991. [11] GEMZA N, JANIAK K, ZIEBA B, et al. Long-term effects of hydrocyclone operation on activated sludge morphology and full-scale secondary settling tank wet-weather operation in long sludge age WWTP[J]. Science of the Total Environment, 2022, 845:157224. [12] WU D, ZHAO B, ZHANG P, et al. Insight into the effect of nitrate on AGS granulation:granular characteristics, microbial community and metabolomics response[J]. Water Research, 2023, 236:119949. [13] TCHOBANOGLOUS G, BURTON F L, STENSEL H D. Wastewater Engineering:Treatment and Reuse[M]. 4th Ed, McGraw-Hill, New York, 2003. [14] 王晓东, 毕学军, 初正崑, 等. 反应温度变化对活性污泥沉降性能的影响分析[J]. 中国给水排水, 2013, 29(23):128-131. [15] LONG B, YANG C Z, PU W H, et al. Rapid cultivation of aerobic granule for the treatment of solvent recovery raffinate in a bench scale sequencing batch reactor[J]. Separation and Purification Technology, 2016, 160:1-10. [16] 熊京忠, 来铭笙, 吉芳英, 等. 细微泥沙粒径对SBR系统污泥性质的影响[J]. 中国给水排水, 2015, 31(13):37-41. [17] MU Y, WAN L, LIANG Z, et al. Enhanced biological phosphorus removal by high concentration powder carrier bio-fluidized bed (HPB):phosphorus distribution, cyclone separation, and metagenomics[J]. Chemosphere, 2023, 337:139353. [18] 钱玉兰, 李燕, 乔椋, 等无机絮凝剂对SBR系统中活性污泥的影响研究[J]. 中国环境科学, 2020, 40(6):2445-2453. [19] 王水兵, 高俊贤, 王燕, 等. 某污水处理厂旋流沉砂池结构改造及运行效果分析[J]. 环境工程, 2020, 38(7):116-121. [20] ZHAO P, ZHAO S, WANG H G, et al. Encapsulation of bacteria in different stratified extracellular polymeric substances and its implications for performance enhancement and resource recovery[J]. Water Research, 2022, 220:118684. [21] AQEEL H, WEISSBRODT D G, CERRUTI M, et al. Drivers of bioaggregation from flocs to biofilms and granular sludge[J]. Environmental Science:Water Research & Technology, 2019, 5(12):2072-2089.
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