Operation And Hydrogen Production Efficiency Of Fluid-solid Co-construction Biofilm Anaerobic Baffled Biological Hydrogen Production Reactor

The rapid development of the economy has accelerated the consumption of fossil energy,while also promoting the development of clean energy such as hydrogen.Biological hydrogen production has been widely recognized because of the low cost,cleaning production process,free pollution and other advantages.The experiment constructed a fluid-solid co-construction biofilm ABR biological hydrogen reactor based on the principle of biological hydrogen production.The starting experiment of the reactor was carried out with molasses wastewater as substrate,and the ABR reactor was compared with molasses wastewater and sweet sorghum pressing wastewater as substrates in running stage.The results showed that,when the temperature was(35+1)oC,the pH value was between 6.50-7.00,the initial HRT was 48 h and the initial COD concentration was 952.4 mg/L,the reactor was started.And the reactor was started successfully at 39th day through the phased regulation of the COD concentration and HRT of the inlet.The COD removal rate,pH value,ORP and other indexes in the reactor began to stabilize,bubbles were produced in the gas-collecting bottle and the system formed ethanol type fermentation.The fluid-solid co-construction biofilm ABR biological hydrogen reactor is carried out using molasses wastewater and sweet sorghum pressing wastewater as substrates.The results showed that the maximum COD removal rate is 53.9 percent when using sweet sorghun pressing wastewater as substrate and the maximum hydrogen yield in a single day got maximum value of 60.38 L at 7500 mg/L COD concentration.When the substrate was molasses wastewater,the maximum COD removal rate reached 75.7 percent,but the maximum hydrogen production value of 48.2 L/d appeared in the COD concentration of about 7000 mg/L.It indicated that when the substrate was sweet sorghum pressing wastewater,the ABR system has higher hydrogen production efficiency but lower COD removal capacity.It can be considered to using sweet sorghum pressing wastewater as substrate of hydrogen production system.The first chamber maintained the maximum COD removal ability during the start-up operation,while the second and third chambers have the strongest hydrogen production capacity and high acetic acid content,which indicates that the dominant population of the first chamber is the acid-producing fermented bacteria group,while the dominant population of the second chamber is the acetic acid and hydrogen-producing bacteria,and the ABR system maintains good microbial separation characteristics.The fluid-solid co-construction biofilm ABR biological hydrogen reactor showed good stability during the start-up and running stage.It always maintained a stable ethanol type fermentation system.And compared with the common ABR biological hydrogen reactor,it has better COD removal capacity and hydrogen production efficiency.