Elevated Vertical-Flow Constructed Wetlands for Light Greywater Treatment

Integrated planning of urban blue–green infrastructures is crucial to strengthen urban environmental quality and mitigate negative climate change-associated effects. It implies, however, increased water demand for irrigation, wherefore greywater (wastewater excluding wastewater from toilets and urin...

Full description

Bibliographic Details
Main Authors: Carlo Morandi, Gerhard Schreiner, Patrizia Moosmann, Heidrun Steinmetz
Format: Article
Language:English
Published: MDPI AG 2021-09-01
Series:Water
Subjects:
Online Access:https://www.mdpi.com/2073-4441/13/18/2510
id doaj-b8a8042f85c1479b986e60e888c79eb5
record_format Article
spelling doaj-b8a8042f85c1479b986e60e888c79eb52021-09-26T01:38:46ZengMDPI AGWater2073-44412021-09-01132510251010.3390/w13182510Elevated Vertical-Flow Constructed Wetlands for Light Greywater TreatmentCarlo Morandi0Gerhard Schreiner1Patrizia Moosmann2Heidrun Steinmetz3Department for Resource-Efficient Wastewater Technology, Faculty of Civil Engineering, Technische Universität Kaiserslautern, Paul-Ehrlich-Straße 14, 67663 Kaiserslautern, GermanyDepartment for Resource-Efficient Wastewater Technology, Faculty of Civil Engineering, Technische Universität Kaiserslautern, Paul-Ehrlich-Straße 14, 67663 Kaiserslautern, GermanyDepartment for Resource-Efficient Wastewater Technology, Faculty of Civil Engineering, Technische Universität Kaiserslautern, Paul-Ehrlich-Straße 14, 67663 Kaiserslautern, GermanyDepartment for Resource-Efficient Wastewater Technology, Faculty of Civil Engineering, Technische Universität Kaiserslautern, Paul-Ehrlich-Straße 14, 67663 Kaiserslautern, GermanyIntegrated planning of urban blue–green infrastructures is crucial to strengthen urban environmental quality and mitigate negative climate change-associated effects. It implies, however, increased water demand for irrigation, wherefore greywater (wastewater excluding wastewater from toilets and urinals) can be used, yet it requires handling for safe reuse. One treatment option is the use of constructed wetlands (CW), which have thus far not been broadly applied in inner-city districts due to large area requirements. This work investigates a novel bipartite container-based vertical-flow constructed wetland (VFCW) for the treatment of light greywater (from showers and hand wash basins) and its use as irrigation water for urban facade greenery. The VFCW consists of two compartments with 2.5 m<sup>2</sup> filter area each, filled with 75 cm zeolite-containing lava sand (0–4 mm) and 75 cm Rhine sand (0–2 mm), respectively. In short, screening has proven to be well suitable for coarse solids removal, so there is no further need to settle light greywater, which reduces overall treatment area and benefits urban application. Treated greywater complied with irrigation standards at all times, yet mixing with rainwater can help reduce salt contents, if applicable. The modular/elevated lava sand VFCW exhibited extensive nitrification, even at extremely low water temperatures, as well as mean effluent concentrations of 6.3 mg/L COD and <0.05 mg/L P<sub>tot</sub>, which makes it a very promising treatment option for greywater. All in all, the modular/elevated design promotes urban application of VFCW as a multifunctional blue–green system that can help increase urban resilience.https://www.mdpi.com/2073-4441/13/18/2510blue–green infrastructurescontainer-basedlava sandlow temperaturenature-based solutionsnitrification
collection DOAJ
language English
format Article
sources DOAJ
author Carlo Morandi
Gerhard Schreiner
Patrizia Moosmann
Heidrun Steinmetz
spellingShingle Carlo Morandi
Gerhard Schreiner
Patrizia Moosmann
Heidrun Steinmetz
Elevated Vertical-Flow Constructed Wetlands for Light Greywater Treatment
Water
blue–green infrastructures
container-based
lava sand
low temperature
nature-based solutions
nitrification
author_facet Carlo Morandi
Gerhard Schreiner
Patrizia Moosmann
Heidrun Steinmetz
author_sort Carlo Morandi
title Elevated Vertical-Flow Constructed Wetlands for Light Greywater Treatment
title_short Elevated Vertical-Flow Constructed Wetlands for Light Greywater Treatment
title_full Elevated Vertical-Flow Constructed Wetlands for Light Greywater Treatment
title_fullStr Elevated Vertical-Flow Constructed Wetlands for Light Greywater Treatment
title_full_unstemmed Elevated Vertical-Flow Constructed Wetlands for Light Greywater Treatment
title_sort elevated vertical-flow constructed wetlands for light greywater treatment
publisher MDPI AG
series Water
issn 2073-4441
publishDate 2021-09-01
description Integrated planning of urban blue–green infrastructures is crucial to strengthen urban environmental quality and mitigate negative climate change-associated effects. It implies, however, increased water demand for irrigation, wherefore greywater (wastewater excluding wastewater from toilets and urinals) can be used, yet it requires handling for safe reuse. One treatment option is the use of constructed wetlands (CW), which have thus far not been broadly applied in inner-city districts due to large area requirements. This work investigates a novel bipartite container-based vertical-flow constructed wetland (VFCW) for the treatment of light greywater (from showers and hand wash basins) and its use as irrigation water for urban facade greenery. The VFCW consists of two compartments with 2.5 m<sup>2</sup> filter area each, filled with 75 cm zeolite-containing lava sand (0–4 mm) and 75 cm Rhine sand (0–2 mm), respectively. In short, screening has proven to be well suitable for coarse solids removal, so there is no further need to settle light greywater, which reduces overall treatment area and benefits urban application. Treated greywater complied with irrigation standards at all times, yet mixing with rainwater can help reduce salt contents, if applicable. The modular/elevated lava sand VFCW exhibited extensive nitrification, even at extremely low water temperatures, as well as mean effluent concentrations of 6.3 mg/L COD and <0.05 mg/L P<sub>tot</sub>, which makes it a very promising treatment option for greywater. All in all, the modular/elevated design promotes urban application of VFCW as a multifunctional blue–green system that can help increase urban resilience.
topic blue–green infrastructures
container-based
lava sand
low temperature
nature-based solutions
nitrification
url https://www.mdpi.com/2073-4441/13/18/2510
work_keys_str_mv AT carlomorandi elevatedverticalflowconstructedwetlandsforlightgreywatertreatment
AT gerhardschreiner elevatedverticalflowconstructedwetlandsforlightgreywatertreatment
AT patriziamoosmann elevatedverticalflowconstructedwetlandsforlightgreywatertreatment
AT heidrunsteinmetz elevatedverticalflowconstructedwetlandsforlightgreywatertreatment
_version_ 1716868569418956800