The use of integrated constructed wetlands (ICW) for the treatment of separated swine wastewaters

Abstract

The use of constructed wetlands for the treatment of wastewater is an approach that has received increasing attention over the last 30 years due to their innate ability to deal with a wide range of highly variable influent types. The treatment of swine wastewater is an on-going issue due to its generally higher nutrient concentrations and the limited land available to owners. The implementation of the European Union Nitrates Directive and Water Framework Directive is currently placing considerable pressure on agriculture in EU member states with its focus on the improvement and sustained quality of surface waters. The limit of 170 kg of organic nitrogen/ha/annum imposed by the Nitrates Directive can cause severe difficulties for wastewater management in the piggery industry in Ireland, where spreadlands are already receiving high application rates of organic N. A replicated mesocosm integrated constructed wetland (ICW) approach was examined for the effective treatment of anaerobically digested separated swine wastewater with emphasis on nutrient removal. These mesocosm systems are based on operations identified in the available literature as well as on the ICW Concept pioneered in Ireland. The removal efficiency yielded substantial results over an 18 month period and highlighted high mass removal of ammonia-nitrogen (98.1-99.9%) from the influent. The removal recorded in all operational replicates throughout the study period showed that wetlands based on the ICW concept may very well prove to be a viable and sustainable approach for the treatment of swine wastewaters in Ireland whilst successfully addressing both the Nitrates and Water Framework Directives.

Constructed Wetlands for Water Quality Improvement: A Synthesis on Nutrient Reduction from Agricultural Effluents

“…Constructed wetlands are considered relatively low-cost and low-maintenance opportunities for livestock wastewater management, specifically in regions with limited land for spreading manure (Harrington et al, 2012). The greatest challenges for the operation and continued performance of these systems include clogging (De la Varga et al, 2013), managing the large footprint (Masi et al, 2017), and the limited P adsorption capacity (Mankin and Ikenberry, 2004).…”

Constructed wetlands with light expanded clay aggregates for agricultural wastewater treatment

“…In recent years, the use of constructed wetlands (CWs) for the treatment of agricultural wastewaters, including those produced by food-processing industries and by livestock farms, has been gaining popularity due to their relatively low construction costs and maintenance requirements (Cronk, 1996;Knight et al, 2000;Del Bubba et al, 2004;Carty et al, 2008;Harrington and McInnes, 2009;Yalcuk et al, 2010;Herouvim et al, 2011;Yalcuk, 2011;Harrington et al, 2012;Kapellakis et al, 2012;Justino et al, 2012). Their use as buffer zones to provide effective protection of water bodies from agricultural runoff events, namely for the containment of associated pesticide contamination hazards, has also been studied and applied (Gregoire et al, 2009;Warsaw et al, 2012;Matamoros et al, 2012b).…”

An overview of Irish pig production, research and knowledge transfer since 1960

“…Those investigated by Teagasc include anaerobic digestion (Xie et al, 2011a(Xie et al, , 2011b(Xie et al, , 2012a(Xie et al, , 2012b(Xie et al, , 2017, composting (Nolan et al, 2011;Troy et al, 2012Troy et al, , 2013b and pyrolysis (Troy et al, 2013a(Troy et al, , 2013b(Troy et al, , 2014. Treatment of the liquid fraction of pig manure through integrated constructed wetlands (ICW; Harrington et al, 2012), woodchip biofilters (Carney et al, 2013(Carney et al, , 2016 and intermittently aerated sequencing batch reactors (Zhang et al, 2011(Zhang et al, , 2012 was also assessed. However, none of these technologies are currently cost-effective in Ireland, other than in limited scenarios (e.g.…”