Oxygen Monitoring Equipment for Sewage-Sludge Composting and Its Application to Aeration Optimization

Abstract

Oxygen is an important parameter for organic-waste composting, and continuous control of the oxygen in a composting pile may be beneficial. The oxygen consumption rate can be used to measure the degree of biological oxidation and decomposition of organic matter. However, without having a real-time online device to monitor oxygen levels in the composting pile, the adjustment and optimization of the composting process cannot be directly implemented. In the present study, we researched and developed such a system, and then tested its stability, reliability, and characteristics. The test results showed that the equipment was accurate and stable, and produced good responses with good repeatability. The equilibrium time required to detect oxygen concentration in the composting pile was 50 s, and the response time for oxygen detection was less than 2 s. The equipment could monitor oxygen concentration online and in real time to optimize the aeration strategy for the compost depending on the concentration indicated by the oxygen-measuring equipment.

Devitalization of Bacteria in Composted Cattle Manure with Natural Additives and Risk for Environment

“…The level of oxygen during composting without turning is lower than in aerated composted manure. Lower oxygen levels inhibit aerobic microorganisms' activity and metabolism, which lowers pile temperature and lengthens the composting process [31]. Conversely, O 2 molecules can reach composted manure substrates due to the porosity of clinoptilolite.…”