Implementation of online VFA sensor for the control and optimization of the anaerobic process for low cost biogas from manure

A VFA (Volatile Fatty Acids) sensor on headspace chromatography technique had been constructed and implemented for online monitoring of the lab-scale and the pilot-scale manure digester. The sensor has shown very satisfying results in terms of sensitivity and reliability for monitoring the biogas process. The combination of biogas production, total VFA concentration and proprionate concentration could effectively reflect the dynamic state of the process which was very crucial for autmatic control. The implementation of the sensor in full-scale biogas plants would need som optimisation to minimize the maintenance under long-term operation. (Energy 11)