Related Experiment Video

Updated: Jun 17, 2026

Preparation of Free-Surface Hyperbolic Water Vortices
04:35

Preparation of Free-Surface Hyperbolic Water Vortices

Published on: July 28, 2023

Free water content and sludge retention time: impact on oxygen transfer in activated sludge

Jochen Henkel1, Peter Cornel, Martin Wagner

  • 1Technische Universitat Darmstadt, IWAR, Wastewater Technology, Petersenstrabetae 13, 64287 Darmstadt, Germany. j.henkel@iwar.tu-darmstadt.de.

Environmental Science & Technology
|December 24, 2009
PubMed

More Related Videos

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor15:19

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor

Published on: October 15, 2015

A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities08:13

A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities

Published on: December 25, 2015

Related Concept Videos

Bioreactor Controls-II01:18

Bioreactor Controls-II

In aerobic fermentations, oxygen is vital for microbial growth and metabolite production. Since air comprises only about 20% oxygen and the gas is poorly soluble in water—just 9 ppm at 20°C—supplying sufficient oxygen becomes a critical challenge, especially in high-demand processes like yeast growth or citric acid production. Even a fully saturated broth may offer only a few seconds of oxygen availability.To address this, sterile or scrubbed air is introduced into the fermentor via a sparger...
Biological Treatment of Effluent and Waste Water01:30

Biological 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...
Microbial Wastewater Treatment01:30

Microbial 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.
Porosity and Absorption of Aggregate01:20

Porosity and Absorption of Aggregate

Aggregates contain pores of varying sizes; while some are completely enclosed within the particles, others open onto the surface, allowing water to penetrate. The porosity of aggregates is a major factor contributing to the overall porosity of concrete, given that aggregates constitute about three-quarters of concrete's volume.
When all pores in an aggregate are filled with water, the aggregate is considered saturated and surface-dry. If left in dry air, water will evaporate until the aggregate...
Oxygen Transport in the Blood01:27

Oxygen Transport in the Blood

Hemoglobin (Hb) is a crucial molecule in the human body, consisting of four polypeptide chains, each bound to an iron-containing heme group. This unique structure enables hemoglobin to bind to oxygen, with each molecule capable of combining with four molecules of oxygen, leading to rapid and reversible oxygen loading. When fully loaded with oxygen, it is called oxyhemoglobin, while hemoglobin that has released oxygen is called reduced hemoglobin or deoxyhemoglobin. As hemoglobin binds oxygen,...
Oxygen Requirements and Growth Patterns01:29

Oxygen Requirements and Growth Patterns

Microorganisms exhibit diverse oxygen requirements and growth patterns driven by their metabolic strategies and environmental adaptations. Oxygen, while essential for many organisms, can also be toxic under certain conditions, shaping how microorganisms grow and survive.Oxygen Requirements of MicroorganismsMicroorganisms are classified based on their ability to use or tolerate oxygen:● Obligate aerobes like Mycobacterium tuberculosis need oxygen for energy production, as it serves as the...