Characteristics of photothermal transfer and biochemical reaction in up-flow direct absorption hydrogen reactor with embedded ribs

The anaerobic fermentation process of microbial community is a promising method to treat wastewater with high ammonia nitrogen, but it needs to provide suitable temperature. An innovative direct absorption anaerobic reactor was established to reduce the temperature fluctuation of biogas slurry by adding ribs to ensure the high efficiency and stability of anaerobic fermentation process. The effects of flow rate and number of ribs on gas production in the process of photothermal conversion and anaerobic fermentation were analyzed by numerical simulation. The results show that the addition of ribs can effectively reduce temperature fluctuation and increase gas production. Compared with 2269.7 mL/L gas production and temperature fluctuation of up to 8 K without ribs, the gas production increased by 863.1 mL/L and decreased to 0.1624 K when the number of ribs was 9, respectively. Simultaneously, a curve was fitted according to gas production to predict the best working conditions.