Anaerobic Digestion

Anaerobic digestion (AD) is a series of processes in which microorganisms break down biodegradable material in the absence of oxygen. The process is used for both industrial and communal purposes to process waste flows and generate energy. Well-known fermentation applications are co-digestion of animal manure in combination with vegetable material in the agricultural sector, digestion of organic waste and the digestion of sewage treatment sludge.

As part of an integrated waste management system, the anaerobic digestion reduces the emissions of landfill gas into the atmosphere. Anaerobic digestion is widely used as a green energy supply because the process produces a biogas rich in methane that is suitable for energy production, which helps to reduce the use of fossil fuels. The nutrient rich digestate that is produced during the process can be used as a fertilizer in agriculture.

The fermentation process starts with the bacterial hydrolysis of the material to be fermented in order to break down the insoluble organic polymers, such as carbohydrates, and make them available to other bacteria. Acidogenic bacteria convert the sugars and amino acids into carbon dioxide, hydrogen, ammonia and organic acids. Acetogenic bacteria convert these organic acids into acetic acid, extra ammonia, hydrogen and carbon dioxide. Finally, the methanogenic strains convert these products into methane and carbon dioxide.

Nevertheless, from time to time anaerobic digestion systems experience operational problems, such as:


  1. Sour digestion – caused by the build-up of acid with simultaneous delay or standstill of the biogas production
  2. Grease blankets – caused by the buildup of insolubles on the surface of the digester.
  3. Foaming – caused by filamentous bacteria that end up with the biological sludge from the aeration tank of the waste water treatment in the AD installation.
  4. Nutrient imbalance – caused by the lack of certain key micronutrients. This slows the sludge stabilization process.

QM Environmental Services Nederland offers solutions that can help solve and prevent these problems. Contact us for more information about how QM Environmental Services Nederland products and services can help optimize your AD system

Contact us for more information about our products.

A) Starter package Trace element analysis.
Incl. deficiency analysis and product proposal

  • Analysis of 2 samples on a total of 13 trace elements
  • Identification of nutrient shortages
  • If necessary: Recommendation of a trace element mix and advice on application

B) Control analysis Trace elements dosage

  • For control and monitoring of changes or accumulation in the trace element concentration
Standard nutrient mix for anaerobic digestion plants Improves the performance of anaerobic digestion plants. Strengthens the breakdown of fats and increases gas production
Liquid biocompatible antifoaming agent for the control of biologically formed foam layers in wastewater treatment and AD plants. It has been formulated for use in aeration tanks and fermentation tanks to suppress foaming without inhibiting the biomass in its activity or causing other negative side effects often associated with the use of conventional defoamers.
A natural product that results in an improved ecosystem in the anaerobic digester. The microorganisms present in the digester, which are responsible for the conversion of organic material and derive their energy from this conversion, can work optimally through the use of BioStym. This results in an improved methanogenic phase of the fermentation process, which ensures a higher biogas yield. Scientific research has shown that, independently of the fermentation reactor volume, an increase of 5 to 25% in biogas production is achieved.