Welcome back to the next article in our Monitoring 101 series! We are beyond excited to continue our deep dive into the best practices for monitoring biogas operations.

Real-time monitoring in biogas operations is a critical practice that involves the continuous measurement and tracking of a wide range of parameters to ensure optimal process performance and maximize the efficiency of anaerobic digestion. By closely monitoring these key parameters, operators can gain valuable insights into the health and stability of the biogas plant, allowing for timely actions and informed decision-making. This is even more relevant when considering feedstock, one of the cornerstones of all biogas projects. In the journey to creating efficient data-driven biogas project management we have identified the following as key feedstock parameters to keep an eye on:

Feedstock Quality & Quantity

Monitoring the quantity and quality of feedstock is crucial for maintaining the desired feedstock-to-microorganism (F/M) ratio, which is essential for efficient biogas production and preventing process inefficiencies. It is necessary to closely monitor any changes in the amount of feeding and the composition of the feedstock, as these factors can significantly impact the stability and performance of the biogas production. The quality of the feedstock may include total solid (TS), volatile solid (VS), chemical oxygen demand (COD), nutrient content, etc.

To ensure accurate monitoring, it is important to record the mass of input feedstocks to the digester and establish robust monitoring systems for the feeding process. For example, in some cases a deviation of even less than 10% in the feedstock quantity can lead to a significant decrease in biogas production, highlighting the importance of precise monitoring.

Total Kjeldahl Nitrogen in Feedstock

Particular attention should be given to monitoring the TKN (total Kjeldahl nitrogen) content of feedstocks, as it directly affects the ammonia levels in the digester. Excessive ammonia accumulation can inhibit the activity of microorganisms and negatively impact biogas production. It is recommended to maintain TKN levels below 3-5 g/kg to avoid ammonia inhibition.

By implementing comprehensive monitoring strategies, biogas plant operators can make informed decisions and optimize the biogas production process.

Additional Feedstock Parameters to Monitor

Different studies have been done to showcase the impact of changes in feedstock quality on the overall biogas production and microbial communities in the reactors. For this reason, several key feedstock characteristics have been identified which should be monitored to assess their impact on the biogas process. This includes proper monitoring of the following:

  • Total solid
  • Volatile solid
  • Protein
  • Fat
  • Carbohydrates
  • Other influential nutrients

Monitoring of these parameters allows for a more in-depth understanding of feedstock composition and biogas production

Frequent monitoring of other feedstock characteristics such as pH, COD, and biochemical methane potential (BMP) enables operators to identify potential issues or deviations from optimal conditions promptly. This proactive approach facilitates timely adjustments and interventions, ensuring stable and efficient biogas production.

Embracing data-driven decisions in biogas operations through real-time feedstock monitoring is a powerful new tool for the modern biogas industry. By harnessing the power of data, biogas plant operators can make informed choices, maximize efficiency, and enhance sustainability, ensuring a greener, more efficient, and economically viable future for biogas production.

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