Mineralisation and pathogen removal in gravel bed hydroponic constructed wetlands for wastewater treatment

Williams, J.; Bahgat, M.; May, Eric; Ford, MG; Butler, John E.

doi:10.2166/wst.1995.0125

Cited by 34 publications

(27 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Bacterial reduction in porous media is normally attributed to diverse mechanisms besides the filtration, such as adsorption, microbial death and the so-called "die off" of bacterial cells (Torrens et al 2009) which also happened in the MSL system. Williams et al (1995) confirmed the ability of the hydroponic gravel layers of constructed wetlands to achieve a reduction of two log units for E. coli and total coliforms. The adsorption phenomenon is expected to occur at the soil mixture layers in the MSL system.…”

Section: Discussionsupporting

confidence: 59%

Removal of bacterial indicators and pathogens from domestic wastewater by the multi-soil-layering (MSL) system

Latrach

Masunaga

Ouazzani

et al. 2014

Soil Science and Plant Nutrition

View full text Add to dashboard Cite

This paper presents the performance and behavior of a multi-soil-layering (MSL) system to remove fecal contamination bacteria indicators and pathogens from domestic wastewater. The experimental setup was performed using a laboratory-scale MSL system (depth 30 × width 36 × height 65 cm). The MSL system was composed of soil mixture blocks (SMB) arranged in a brick-like pattern and surrounded by permeable gravel layers (PL). The SMB comprised sandy soil, charcoal, sawdust and metal iron at a dry weight ratio of 7:1:1:1. The hydraulic loading rate was 200 L m −2 day −1. Bacteriological analyses comprised total bacterial count at 22 and 37°C, fecal coliforms, total coliforms, Escherichia coli, streptococci, intestinal enterococci and pathogenic bacteria: Clostridium sp., Staphylococcus sp., Pseudomonas sp. and Salmonella sp. The best removal efficiency was achieved for Staphylococcus sp. by 1.42 log unit, while the lowest removal efficiency was found for E. coli by 1.01 log unit. The mean removal efficiencies of total suspended solids (SS), biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total nitrogen (TN) and total phosphorous (TP) were 93, 86, 81, 78 and 80%, respectively. Based on these results, the MSL system could efficiently remove organic matter, phosphorus and nitrogen. However, the performance to reduce bacterial indicators and pathogens was still moderate.

show abstract

Section: Discussionsupporting

confidence: 59%

Removal of bacterial indicators and pathogens from domestic wastewater by the multi-soil-layering (MSL) system

Latrach

Masunaga

Ouazzani

et al. 2014

Soil Science and Plant Nutrition

View full text Add to dashboard Cite

show abstract

“…Treatment cells using P. australis were much more efficient than those employing cattails, Typha angustifolia L. (House et al 1994). Phragmites australis has also been used in gravelbed hydroponic sewage-treatment systems to stimulate nitrification/denitrification activity, thereby increasing the efficiency of these treatments (Williams et al 1994;Williams et al 1995). Urbanc-Bercic and Bulc (1995) and increased reed stand density.…”

Section: Economic Importancementioning

confidence: 99%

“…In the UK and Egypt, water treatment systems with P. australis were found to be effective in reducing biochemical oxygen demand, in controlling the level of pathogens, and in increasing mineralization (Williams et al 1995). Phragmites australis, like most emergent plants, has a high metal uptake capability in the root system and is currently being used for biological detoxification in natural and constructed wetlands (Dunbabin and Bowmer 1992).…”

Section: Economic Importancementioning

confidence: 99%

The biology of Canadian weeds. 129. Phragmites australis (Cav.) Trin. ex Steud.

Mal¹,

Narine²

2004

Can. J. Plant Sci.

View full text Add to dashboard Cite

-common reed, is a perennial, emergent aquatic plant with annual cane-like stems developed from an extensive rhizome system. It grows in low-lying wet areas such as fresh and salt-water marshes, drainage ditches, shallow lake edges, sandy banks, roadsides, woodlands and rocky places. Stems can reach up to 6.0 m in height, vary in diameter from 4 to10 mm and have 10 to 25 cm long hollow internodes. Clones are extended by perennial rhizomes with extensive aerenchymatous tissue that supplies oxygen. Roots develop from rhizomes and other submerged parts of shoots. Leaves are smooth, alternate with narrow-lanceolate laminae, 20 to 70 cm long and 1 to 5 cm broad, and tapering to long slender points. The inflorescence is a terminal panicle, often 30 cm long, dull purple to yellow, with main branches bearing many spikelets. Seed production and germination are extremely variable and comparatively rare in many populations. Phragmites australis carries out photosynthesis through the C 3 pathway (or a variation thereof). Studies of genetic variation through isozyme and other molecular methods suggest that the populations are very closely related, and that variation in the metapopulation is small. Chloroplast DNA sequences of two non-coding regions indicate that non-native introduced genotypes of P. australis have displaced native genotypes in parts of North America. Phragmites australis often forms extensive monocultures in North America. As a consequence, habitat quality and species diversity have been documented to decline. However, in roadside populations it is effective in taking up many typical heavy metals that originate from nearby highways and buildings. Phragmites australis is found in all Canadian provinces and the Northwest Territories, but not in the Yukon Territory or Nunavut. The infestation of P. australis is most severe in the Great Lakes region and its migration is primarily mediated through rivers, canals and waterways but roadways are increasingly becoming important. Changes in the water regime have been linked to its success and could ultimately result in changes to the floristic composition of a habitat. Rodeo™, an aqueous solution of the isopropylamine salt of glyphosate, is most frequently used to control P. australis populations. Other methods of control include cutting, burning, and drainage of the species' habitat. As P. australis is considered to be invasive in North America, introduction of biological control agents is now being investigated. Can. J. Plant Sci. 84: 365-396. Le roseau commun Phragmites australis (Cav.) Trin. ex Steud. est une vivace aquatique dont le vaste système de rhizomes donne chaque année des tiges ressemblant à des cannes. L'espèce pousse dans les dépressions humides comme les marais d'eau douce et salants, les fossés de drainage, la rive des lacs peu profonds, les berges sablonneuses, le bord des routes, les boisés et les endroits rocailleux. Les tiges atteignent parfois jusqu'à 6,0 m de hauteur et leur diamètre varie de 4 à 10 mm, avec de longues sections creuses de 10 à ...

show abstract

“…Variation in EV reduction may be high due to wide changes in physical conditions and biological compositions of plants and microorganisms in different wetlands. A combination of elevated water temperature and biological activities in natural wetland water reduced PV1 by 1 to 4 log 10 (Rachmadi et al, 2016) and EV removal ranged from 2 to 3 log 10 (Williams et al, 1995). Additional data on removal of EVs in wetlands for wastewater treatment are given in Table 14.…”

Section: Wetlandsmentioning

confidence: 99%