Domestic wastewater treatment performance using constructed wetland

Abstract

Constructed wetlands are treatment systems that use natural processes involving wetland vegetation, soils, and their associated microbial assemblages to improve water quality. These systems can be used commercially for efficient biological treatment of wastewater, and it will also act as a better eco-friendly method when compared with other conventional treatment methods. A constructed wetland pilot scale unit was constructed in the SRM University campus which was allowed to treat wastewater from the sewage treatment plant III. The pilot scale unit was designed based on EPA and CPCB guidelines. The dimension of the constructed wetland was 250 9 150 9 80 cm with a slope of 0.01 (1 %). The design is as per Darcy's law. The wetland unit has a cross section of 3.75 m 2 and has been designed with hydraulic loading of 0.8 m 3 /(m 2 /day) and recommended flow of 3 m 3 /day. The retention time provided for the unit was 24, 48, 72, 96, and 120 h. Phragmites australis also known as common reed was the wetland plant species planted in the unit. Six field trials were carried out during the project and with average removal efficiencies of 75.99 % for BOD, 76.16 % for COD, 57.34 % for TDS, 62.08 % for Nitrate, 58.03 % for Phosphate, 57.83 % for Potassium.

Microbial population dynamics in constructed wetlands: Review of recent advancements for wastewater treatment

“…Compost was used as a substrate for treating wastewater in vertical flow wetlands from refineries where total suspended solids, COD, BOD and heavy metals were removed with significant removal percentages [78]. The use of coal slag bed to treat domestic wastewater showed 60% removal efficiency for carbonaceous matters, 50% removal of ammonia nitrogen, 40% for phosphorus and 80% efficiency in removing total suspended solids [79]. Gravel and Zeolite were also experimented as bedding material and the average removal efficiencies for ammonia nitrogen, COD, Phosperous and Fe(III) were compared for units operating in horizontal and vertical modes.…”

Removal of inorganic impurities from wastewater after production of soda ash on selected sorbents

“…The use of reverse osmosis to remove potassium allowed to reduce its concentration by up to 97% 17,25 . Biological treatment on constructed wetlands decreased potassium concentration for almost 60% 18 . In this case results obtained in the experiment are similar to effects of nanofiltration, what suggests potential of sorbents in further study.…”

“…Striving to improve water quality, reduce costs associated with environmental protection and eliminate pollution at the source according to cleaner production assumptions causes that industrial plants are actively seeking innovative and effective ways to protect water resources. Individual ions present in such wastewater could be removed from wastewater among others in the processes of nanofiltration, reverse osmosis, precipitation, biological treatment, ion exchange resins [12][13][14][15][16][17][18][19] . However, most of them are expensive and ineffective in relation to all mentioned ions simultaneously.…”

Bacteriological Quality of a Forage Grass (<i>Pennisetum purpureum Schumach</i>) Used in Constructed Wetland Removing Domestic Wastewater Pathogenic Microorganism

“…Constructed wetlands (CWs) are artificial engineered wastewater treatment systems that use natural processes involving wetland vegetation, soils substrates (i.e. sand, stones, clay), and their associated bacteria and invertebrates population to improve water quality [1] [2]. These systems are increasingly recognized as a reliable wastewater treatment technology due to their efficiency, low energy consumption, good landscape integration and aesthetic appearance, but above all, due to the possible valorization of the above-ground biomass of the plant species used [3] [4].…”