5 - Anaerobic Digestion 2

These flashcards cover essential vocabulary related to the anaerobic digestion process, including key terms, definitions, and concepts that are important for understanding the lecture material.

Anaerobic Digestion

A biological process where microorganisms break down organic matter in the absence of oxygen, producing biogas and digestate.

Hydraulic Retention Time (HRT)

The average time that material stays in the digester vessel, calculated by dividing the digester working volume by the daily influent flow rate.

Organic Loading Rate (OLR)

The amount of organic matter fed into the digester per unit volume per unit time, expressed as kg COD m-3 day-1 or kg VS m-3 day-1.

Thermophilic Digestion

Anaerobic digestion that occurs at higher temperatures (55-60 °C), which can enhance the degradation of organic matter.

Mesophilic Digestion

Anaerobic digestion that occurs at moderate temperatures (35-40 °C), which is commonly used for many types of organic waste.

Volatile Acids

Short-chain fatty acids produced during the anaerobic digestion process; their concentration indicates the stability of the digester.

pH Control

Maintenance of appropriate acidity/basicity levels in the digester to optimize microbial activity and biogas production.

Toxicity

The presence of harmful substances that can inhibit microbial activity in the anaerobic digestion process.

Pre-treatment

Processes applied to feedstocks to enhance their biodegradability and subsequent biogas production efficiency.

Digester

A sealed vessel where anaerobic digestion takes place, enabling the conversion of organic materials into biogas and digestate.