Influence of hydraulic loading rate and recirculation on oxygen transfer in a vertical flow constructed wetland

2019 ◽  
Vol 668 ◽  
pp. 988-995 ◽  
Author(s):  
Samara T. Decezaro ◽  
Delmira B. Wolff ◽  
Catiane Pelissari ◽  
Rolando J.M.G. Ramírez ◽  
Thiago A. Formentini ◽  
...  
Keyword(s):  
Constructed Wetland ◽  
Oxygen Transfer ◽  
Loading Rate ◽  
Vertical Flow ◽  
Hydraulic Loading Rate ◽  
Hydraulic Loading ◽  
Vertical Flow Constructed Wetland

Effects of Hydraulic Loading Rate on Nutrient Removal in Multi-Stage Constructed Wetland

2013 ◽  
Vol 864-867 ◽  
pp. 1498-1502
Author(s):  
Qing Feng Chen ◽  
Wen Guo Dong ◽  
Jun Jian Ma ◽  
Qing Li ◽  
Xin Guo Gao ◽  
...  
Keyword(s):  
Constructed Wetland ◽  
Loading Rate ◽  
Optimal Parameter ◽  
Removal Rate ◽  
Operational Parameter ◽  
Hydraulic Loading Rate ◽  
Hydraulic Loading ◽  
Multi Stage ◽  
Operation Period ◽  
D 12

Hydraulic loading rate (HLR) is an important operational parameter for constructed wetland to purify wastewater. In this paper, it is the main objective to select the optimal parameter of HLR. During the four HLRs (i.e., 6 cm/d, 12 cm/d, 24 cm/d and 48 cm/d) operation period, six days were used as one stage. The experimental results showed that the best average removal rates of CODcr (59.7%) and NH3-N (89.4%) were at the HLR of 6 cm/d. In the meantime, the best average removal rate of total phosphorus (TP, 50.0%) was at the HLR of 24 cm/d. According to the low influent TP concentration, it is suggested that the HLR of 6 cm/d should be used in the multi-stage constructed wetland.

Influence of earthworm presence and hydraulic loading rate on the performance of vertical flow constructed wetlands

2020 ◽  
pp. 1-9 ◽  
Author(s):  
Alexandre Atalla ◽  
Catiane Pelissari ◽  
Milina de Oliveira ◽  
Mariana Antonio de Souza Pereira ◽  
Priscila Sabioni Cavalheri ◽  
...  
Keyword(s):  
Constructed Wetlands ◽  
Loading Rate ◽  
Vertical Flow ◽  
Hydraulic Loading Rate ◽  
Hydraulic Loading ◽  
Vertical Flow Constructed Wetlands

scholarly journals Purification ability of tail water and optimal hydraulic loading rates in vertical flow constructed wetland

2016 ◽  
Vol 28 (1) ◽  
pp. 114-123
Author(s):  
LIANG Kang ◽  
◽  
CHANG Junjun ◽  
WANG Feihua ◽  
LIU Shuangyuan ◽  
...  
Keyword(s):  
Constructed Wetland ◽  
Vertical Flow ◽  
Loading Rates ◽  
Hydraulic Loading ◽  
Vertical Flow Constructed Wetland ◽  
Tail Water

scholarly journals Performance of the first stage of the French system of vertical flow constructed wetlands with only two units in parallel: influence of pulse time and instantaneous hydraulic loading rate

2018 ◽  
Vol 78 (4) ◽  
pp. 848-859 ◽  
Author(s):  
Jorge A. García Zumalacarregui ◽  
Marcos von Sperling
Keyword(s):  
Constructed Wetlands ◽  
Loading Rate ◽  
Oxygen Demand ◽  
Feeding Time ◽  
Vertical Flow ◽  
Hydraulic Loading Rate ◽  
Hydraulic Loading ◽  
Vertical Flow Constructed Wetlands ◽  
Removal Efficiencies ◽  
Raw Wastewater

Abstract The technology of vertical flow constructed wetlands – French system for treating raw wastewater depends on several hydraulic factors, one of them being the duration of the pulse feeding and the resulting instantaneous hydraulic loading rate. This paper analyses two scenarios in the same system, the first of a faster feeding by pump and the second of a slower feeding by siphon, both with instantaneous hydraulic loading rate values lower than the literature recommendations. The system treated raw wastewater from a population equivalent of 100 p.e. in Brazil, and was comprised by only the first stage and two units in parallel. The shorter duration of feeding time and higher instantaneous hydraulic loading rate were associated with significantly higher chemical oxygen demand and total Kjeldahl nitrogen removal efficiencies, but with no significant differences in terms of biochemical oxygen demand (BOD) and suspended solids (SS). Oxygen concentrations and redox potential in the effluent were evaluated, together with the effluent flow rate profiles. The removal efficiencies were associated with the accumulation of solids in the upper part of the filter resulting from seven years of operation and to the operating hydraulic conditions, which are important elements in the performance of the system.

scholarly journals A tracer study in a vertical flow constructed wetland treating septage

2018 ◽  
Vol 15 (3) ◽  
pp. 345-353 ◽  
Author(s):  
Jason Jie Xiang Bui ◽  
Yee Yong Tan ◽  
Fu Ee Tang ◽  
Carrie Ho
Keyword(s):  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Retention Time ◽  
Evaluation Method ◽  
Hydraulic Retention Time ◽  
Vertical Flow ◽  
Content Type ◽  
Hydraulic Loading ◽  
Hydraulic Behaviour ◽  
Vertical Flow Constructed Wetland

Purpose This study aims to investigate the hydraulic behaviour of a pilot-scale, two-staged, vertical flow constructed wetland (VFCW) for septage treatment, in terms of factors such as hydraulic retention time and hydraulic loading rate and its influence on the treatment dynamics. Because of intermittent feeding mode of VFCW systems and variation in its loading, its hydraulic behaviour is highly variable and need to be understood to optimize its treatment performance. Design/methodology/approach Tracer test were carried out using bromide ion with varying hydraulic loading rates (HLR) of 6.82 cm/d, 9.09 cm/d and 11.40 cm/d (i.e. equivalent to 75 L/d, 100L/d and 125 L/d). Tracer data is then analysed using the Residence Time Distribution (RTD) method. Findings RTD analysis showed that the increase in HLR increases the average hydraulic retention time (HRT). Subsequently, the increase in HLR results in a lower recovery of effluent, resulting in poor productivity in treatment. The study also showed that the removal of nitrogen and organic matter improved with increasing HRT. However, observations show no correlation between HRT and total solids removal. Originality/value A performance evaluation method (by tracer) is proposed to understand the hydraulics of flow in constructed wetlands, which has not been widely studied. Additionally, the dynamics of treatment in VFCWs treating septage may also be revealed by the tracer method. The study can be applied to any constructed wetlands designed for treatment of wastewater, septage or sludge.

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