Related Experiment Video
Updated: Jul 31, 2026
06:42
Measuring Phosphorus Release in Laboratory Microcosms for Water Quality Assessment
Published on: July 22, 2019
Phosphorus removal in a vertical upflow constructed wetland system
N Farahbakhshazad1, G M Morrison
1Department of Applied Environmental Science, Göteborg University, P.O. Box 464, SE-405 30 Göteborg, Sweden. neda@miljo.gu.se
Summary
Phosphorus removal in macrophyte systems is enhanced by increasing flow rates and using intermittent loading. Continuous flow optimizes mass removal, while sand and Phragmites australis show effective phosphorus adsorption.
Area of Science:
- Environmental Science
- Water Treatment Engineering
- Plant Science
Background:
- Phosphorus (P) removal is crucial for preventing eutrophication.
- Macrophyte systems offer a sustainable approach to wastewater treatment.
- Optimizing P removal efficiency in these systems requires understanding substrate and flow dynamics.
Purpose of the Study:
- To investigate phosphorus removal mechanisms in a vertical upflow macrophyte system.
- To evaluate the impact of flow rate, substrate type, and loading strategy on P removal.
- To compare sand and light expanded clay aggregate (LECA) as substrates for P adsorption.
Main Methods:
- Controlled laboratory experiments using vertical upflow columns.
- Systems planted with Phragmites australis and filled with sand or LECA substrate.
- Varied flow rates, effluent recirculation, intermittent, and continuous loading conditions.
- Analysis of phosphorus concentrations in influent and effluent.
Main Results:
- Substrate P removal increased with higher flow rates, achievable via effluent recirculation.
- LECA showed better equilibrium adsorption but no kinetic advantage over sand in this system.
- Intermittent loading allowed control of P concentration, reducing peak effluent levels.
- Continuous flow proved optimal for maximizing total P mass removal.
Conclusions:
- Flow rate and loading strategy significantly influence P removal in macrophyte systems.
- Sand-based systems with Phragmites australis are effective for P removal.
- Optimized flow and loading regimes are key for efficient phosphorus management in constructed wetlands.
Related Concept Videos
04:01Factors Affecting Solubility
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Chȃtelier’s principle. Consider the dissolution of silver iodide:
01:06Coagulation
Colloidal solids are solid particles suspended in solution. They are usually negatively charged, attracting a compact primary layer of positively charged ions, which attract more counterions to form an electrical double layer. Electrostatic repulsion between the charged double layers prevents the particles from colliding, stabilizing the colloids. These solids are often undesirable because they can contain toxins that are difficult to remove. Coagulation is a technique that helps aggregate and...
01:14Conservation of Mass in Moving, Nondeforming Control Volume
Stormwater detention basins are essential in managing runoff during heavy rainfall, particularly in urban areas where impervious surfaces increase the risk of flooding. Understanding the conservation of mass in these systems allows engineers to optimize basin performance, balancing inflow, outflow, and water storage.
In the context of a detention basin, the conservation of mass states that the total mass of water entering the basin must equal the mass leaving the basin plus any accumulation of...
In the context of a detention basin, the conservation of mass states that the total mass of water entering the basin must equal the mass leaving the basin plus any accumulation of...
01:25Microbial Bioremediation of Uranium
Microorganisms play a critical role in the transformation and immobilization of uranium in contaminated environments through four main pathways: bioreduction, biosorption, bioaccumulation, and biomineralization. These mechanisms reduce uranium’s toxicity and prevent its migration through groundwater systems, offering sustainable approaches for in situ bioremediation.Bioreduction of UraniumBioreduction is driven by anaerobic bacteria such as certain strains of Geobacter and Shewanella, which use...
01:30Microbial Wastewater Treatment
Microbial communities in aquatic ecosystems play a key role in the natural breakdown of contaminants introduced through domestic and industrial effluents. Acting as biological catalysts, these microbes change and mineralize a wide range of organic and inorganic pollutants under different redox conditions.In oxygen-rich surface waters, aerobic heterotrophs lead organic matter breakdown, using oxygen as the terminal electron acceptor to efficiently oxidize substrates to carbon dioxide and water.
01:30Biological Treatment of Effluent and Waste Water
Biological wastewater treatment relies on the metabolic activity of microorganisms to remove pollutants from sewage. In modern treatment systems, this process is organized into sequential stages that progressively reduce solid material, dissolved organic matter, and microbial contamination. Each stage plays a distinct role in improving water quality and preparing the effluent for safe discharge or reuse.Primary and Secondary TreatmentPrimary treatment is a physical process that removes large...