A critical review of mineral substrates used as filter media in subsurface constructed wetlands: costs as a selection criterion

ABSTRACT

This study reports a literature review of the state of the art, 2000-2020, on the substrates that are used as support media in constructed wetlands with subsurface flow. Its importance compared to the most used substrates worldwide and its economic feasibility as a substrate in CW. 13 different types of substrates have been identified in 155 different studies, but the most used substrates were gravel (32%) and sand (23%) for the development of bacterial associations. However, gravel and sand used in full-scale CW are expensive (10–35 $USD/m³), for wastewater treatment in small communities with economic difficulties. The tendency is to use substrates such as gravel (32%), sand (23%), sediments (13%), limestone or river rock (11%), granite (8%), zeolite (6%) and other alternative materials (7%). Among these we can mention: ceramics, pumice, steel, bricks, shells of different local aquatic fauna and some stone materials easily found in the study area. Therefore, the development of substrates of lower commercial value, reused material and material of easy operation is important, especially in developing countries where economic resources are one of the main constraints in the implementation of wastewater treatment systems. The use of treatment wetlands with economic materials detected in this study indicate that the future in wastewater treatment is this technology, because present multiple objectives, which include water treatment, fertilizer production, enhancement of biodiversity and cooling, vegetation production for handicraft, etc. CW are a technology with future role in circular economy that want to respond to sanitation worldwide.

GRAPHICAL ABSTRACT

KEYWORDS:

• Wastewater
• constructed wetlands
• substrates
• circular economy
• alternative materials

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data supporting the findings of this study are available within the article.

Additional information

Notes on contributors

Luis Carlos Sandoval Herazo

Luis Carlos Sandoval Herazo, professor in the Wetlands and Environmental Sustainability Laboratory, Division of graduated Studies and Research of the Tecnológico Nacional de México-Instituto Tecnológico Superior de Misantla in México Civil Engineering / University of Sucre (Colombia), Master's Degree in Engineering / Technological Institute of San Andrés Tuxtla (Mexico). Master in Sustainable Regional Development / El Colegio de Veracruz (Mexico). PhD in Sustainable Regional Development / El Colegio de Veracruz (Mexico). Doctorate in Engineering Sciences / Technological Institute of Orizaba (Mexico). Post-Doctorate in Civil Engineering / Francisco José de Caldas District University, Colombia. Research Areas: Environment and sanitation.

Alejandro Alvardo-Lassman

Alejandro Alvarado Lassman, professor in the Research and Graduate Studies Division of the Tecnológico Nacional de México-Instituto Tecnológico de Orizaba Chemical Engineering - Universidad Veracruzana, Master's Degree in Chemical Engineering - Technological Institute of Higher Studies of Monterrey, PhD in Food Sciences - Technological Institute of Veracruz Research Areas: Environmental Biotechnology.

José Luis Marín-Muñiz

Dr. José Luis Marín Muñiz, professor in Academy of Sustainable Regional Development, El Colegio de Veracruz, Xalapa, Veracruz, Mexico. Chemical Engineer, Master in Environmental Sciences, PhD in Tropical Ecology from the Universidad Veracruzana. Post-doctorate in Sustainable Regional Development, El Colegio de Veracruz, Mexico. Research Areas: Biotechnologies to improve environmental quality, Ecological Engineering, Socio-environmental implications and environmental education.

Juan Pablo Rodríguez-Miranda

Juan Pablo Rodriguez-Miranda, professor at the Francisco José de Caldas District University, Colombia. Sanitary Engineer, Master in Sanitary Engineering, PhD in Engineering from the Francisco José de Caldas District University, Colombia. Research Areas: Management and treatment of drinking water and wastewater.

Gregorio Fernández-Lambert

Dr. Gregorio Fernandez Lambert, professor in the Division of graduated Studies and Research of the Tecnológico Nacional de México-Instituto Tecnológico Superior de Misantla in México. Graduate in Chemical Industrial Engineering / Technological Institute of Orizaba (Mexico). Master of Science in Administrative Engineering / Technological Institute of Orizaba (Mexico). PhD in Logistics and SupplyChain Management / Universidad Popular Autónoma del Estado de Puebla (Mexico). Research Areas: Intelligent agroindustrial processes and sustainability.