ZHONGNi-qian,LIYi-pingAN,ZHOUYu-xuan,et al.Evaluation of Operation Efficiency and Quantitative Analysis of Carbon Sources Loss in Sewage Systems in Typical Hilly Area[J].China Water & Wastewater,2024,40(17):1-8.
Evaluation of Operation Efficiency and Quantitative Analysis of Carbon Sources Loss in Sewage Systems in Typical Hilly Area
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第40卷
Number:
第17期
Page:
1-8
Column:
Date of publication:
2024-09-01
- Keywords:
- hilly area; sewage system; external water inflow and infiltration; carbon sources loss; quality and efficiency improvement
- Abstract:
- The dilution by infiltration of external water and the deposition and degradation of pollutants are the key reasons for the loss of carbon sources in sewage systems. Taking a separate sewage system in the East China hilly area as an example, the simultaneous monitoring of water quantity and quality in the source drainage households, sewage pipe network and pump station was carried out. The study aimed to explore the hydraulic characteristics and response of water quality changes in the pipeline network, diagnose operational issues in the system and quantify the proportion of physical dilution, settling and degradation along the process. The results showed that the measured sewage volume of the system was 1.93 times of the theoretical value, indicating severe external water infiltration. The proportion of carbon source attenuation (measured by COD) from the discharged water to the pump station was 32.6%. Significant differences were observed in the operational characteristics of the upper and lower drainage zones. The upper pipeline was running close to full capacity, with some pipelines experiencing pressure flow, 68.6% of the network flow velocity was lower than 0.30 m/s and COD/NH3-N was lower than the downstream. In the downstream area, the average filling degree was 0.57 and COD/ NH3-N gradually decreased. Due to the complex terrain in the hilly area, the slope of the upper pipeline met the design standards but had a large drop, leading to poor drainage, high water levels and particle settling. In the downstream area with lower terrain, external water infiltration diluted pollutants. The carbon source loss mechanism in the typical low water volume and low load efficiency zone was mainly dominated by deposition and degradation, accounting for 74.67%, while in the high water volume high load efficiency zone, external water dilution was the main mechanism, accounting for 94.24%.
Last Update:
2024-09-01