Paper Title
Development of Recirculating Composting Reactors

Abstract
The rapid increase in the world’s population has resulted in increasing industrial and agricultural production. Increasing industrial and agricultural production leads to increasing energy demands and the amount of waste products. A significant part of these waste products is organic. Organic waste products are mostly formed because of agricultural activities, and they lead to significant environmental problems because of pathogen microorganisms and gas emissions. The composting process is an aerobic process that can be part of a sustainable management of waste products. Compost that is produced by this process can be used in agricultural production, fighting against erosion, in forests and landscaping areas to regulate the soil and as manure. In the composting process, microorganisms decompose the organic bonds inside the waste products. Active microorganisms in composting process emit CO2 and heat by consuming the oxygen inside the medium. Temperature change is especially important for the destruction of pathogenic microorganisms in the thermophilic phase. To destroy the pathogenic microorganisms, the composting process needs to proceed at 55°C for at least 3 days. Composting tests performed in composting reactors. Comporting reactor systems are simulating the composting reactions. In this study five experimental composting reactors were developed. In this system air recirculating rate, process temperature, CO2 and O2 concentration of process gas were measured with sensors. Gas analyzing systems have a gas sequencer. This unit sequenced the gas samples of reactors. All units of systems were managed by PLC (programmable logic controller). This study was supported by TUBİTAK (The Scientific and Technological Research Council of Turkey Project Number 216O266). Keywords- Composting, compost automation, air recirculation.