Upflow Evapotranspiration System for the Treatment of On-Site Wastewater Effluent

Water

Sean Curneen¹  Laurence Gill¹ 

关键词: on-site wastewater;    low permeability;    evapotranspiration;    willow;    passive treatment;   

DOI  :  10.3390/w7052037

来源: mdpi

【 摘 要 】

Full-scale willow evapotranspiration systems fed from the base with septic tank or secondary treated domestic effluent from single houses have been constructed and instrumented in Ireland in order to investigate whether the technology could provide a solution to the problem of on-site effluent disposal in areas with low permeability subsoils. Continuous monitoring of rainfall, reference evapotranspiration, effluent flows and water level in the sealed systems revealed varying evapotranspiration rates across the different seasons. No system managed to achieve zero discharge in any year remaining at maximum levels for much of the winter months, indicating some loss of water by lateral exfiltration at the surface. Water sampling and analysis however, showed that the quality of any surface overflow from the systems was similar to rainfall runoff. The performance results have then been used to formulate design guidelines for such systems in Ireland’s temperate maritime climate. The effect of varying different combinations of design parameters (plan area, soil depth, etc.) has been evaluated with respect to the simulated number of overflow days over a five-year period using a water balance model. Design guidelines have then been based upon minimising the amount of runoff, in conjunction with other practical and financial considerations.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.