AUTOMATED PROCESS CONTROL FOR BIOGAS PLANTS

For efficient biogas production, sludge bacteria require a pH in the range of about 6.5 to 8. A stabilization of the pH in this area is mainly achieved ( 85) by the bicarbonate (= buffer substance) released in large quantities during anaerobic degradation.>

Process disturbances regularly lead to increased levels of free fatty acids (FFA) or decreasing bicarbonate levels, as the acids consume bicarbonate. However, the buffering effect of the bicarbonate hardly reduces the pH at first.

Only when the disturbance lasts for a long time and the stock of bicarbonate is largely exhausted, it comes to a rapid drop in pH and subsequently to a reduction or in extreme cases to a failure of biogas production.

ADVANTAGES OF A PROCESS CONTROL WITH THE BICARBONATE ANALYZER

• By fully automatic monitoring of the bicarbonate content with the BA42 Process Monitor, process disturbances can be detected significantly earlier than with the sole pH control. There is more time to avert economic losses.
• The high density of data of the automatic measurement allows a tight time assignment to changed operating conditions. The often difficult determination of causes for process disturbances is much easier in this way.
• Automated measurement enables remote monitoring of biology.
• The BA42 measurement technology thus increases the overall availability of biogas plants and thus their economic success.