Lecture

Denitrification: Water Quality and the Biogeochemical Engine

Graph Chat

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Description

This lecture covers denitrification, a process where nitrate is reduced to N₂ under anoxic conditions, resulting in the net loss of nitrate to the atmosphere. It explains the four steps involved in the reduction of nitrate to N₂, the different nitrate reduction pathways, and the enzymes involved in denitrification. The lecture also discusses denitrifying organisms, nitrate ammonifying organisms, and their metabolic processes. Furthermore, it explores the application of denitrification in wastewater treatment, emphasizing its critical role in removing nitrogen. The lecture concludes by highlighting the importance of denitrification in the nitrogen cycle and its impact on water quality.

Official source

Ontological neighbourhood

Environmental science

Pollution: Water pollution

Related concepts (32)

Nitrogen cycle

The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmospheric, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification. The majority of Earth's atmosphere (78%) is atmospheric nitrogen, making it the largest source of nitrogen.

Nitrogen fixation

Nitrogen fixation is a chemical process by which molecular nitrogen (N2), which has a strong triple covalent bond, is converted into ammonia (NH3) or related nitrogenous compounds, typically in soil or aquatic systems but also in industry. The nitrogen in air is molecular dinitrogen, a relatively nonreactive molecule that is metabolically useless to all but a few microorganisms. Biological nitrogen fixation or diazotrophy is an important microbe-mediated process that converts dinitrogen (N2) gas to ammonia (NH3) using the nitrogenase protein complex (Nif).

Wastewater treatment

Wastewater treatment is a process which removes and eliminates contaminants from wastewater and converts this into an effluent that can be returned to the water cycle. Once returned to the water cycle, the effluent creates an acceptable impact on the environment or is reused for various purposes (called water reclamation). The treatment process takes place in a wastewater treatment plant. There are several kinds of wastewater which are treated at the appropriate type of wastewater treatment plant.

Industrial wastewater treatment

Industrial wastewater treatment describes the processes used for treating wastewater that is produced by industries as an undesirable by-product. After treatment, the treated industrial wastewater (or effluent) may be reused or released to a sanitary sewer or to a surface water in the environment. Some industrial facilities generate wastewater that can be treated in sewage treatment plants.

Sewage treatment

Sewage treatment (or domestic wastewater treatment, municipal wastewater treatment) is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable to discharge to the surrounding environment or an intended reuse application, thereby preventing water pollution from raw sewage discharges. Sewage contains wastewater from households and businesses and possibly pre-treated industrial wastewater. There are a high number of sewage treatment processes to choose from.

Related lectures (64)

Water and Wastewater Treatment: Introduction

Covers the basics of water and wastewater treatment, including the history of wastewater treatment, undesirable pollutants, and treatment performance.

Biological Nutrient Removal: Nitrogen and Phosphorus

Explores biological nutrient removal in wastewater treatment, covering nitrogen and phosphorus removal, activated sludge process, nitrification, denitrification, and phosphorus recovery.

Wastewater Treatment: Nutrient Removal

Explores biological nutrient removal and chemical phosphorous removal in wastewater treatment plants, emphasizing denitrification and phosphate removal methods.

Wastewater Treatment I

Explores wastewater treatment principles, BOD removal efficiency, and typical pollutant concentrations.

Water Protection: Surface and Groundwater