| Mixed strains fermentation biological hydrogen production technology, as one of the important ways to develop new clean and renewable energy has been accepted by people, and how to improve the production efficiency has gradually become a hot research topic.A large number of studies have shown that improve the continuous flow of hydrogen production by anaerobic reactor is one of the effective ways to improve the capacity of producing hydrogen mixed bacteria middle hydrogen microorganism quantity and production activity. Magnetic field has been confirmed can effectively improve the growth of microbes and enzyme activity. And the use of magnetic field to improve the efficiency of the anaerobic biological hydrogen production reactor to produce hydrogen research has not been reported.The condition during start-up was based on the medium temperature (37±1?), 78 mT of static magnetic field, and its operation parameters are optimized, looked at 78 mT magnetic field effect on the reactor start-up process, discusses the pH, C/N and iron ion concentration on the influence of magnetic reactor to produce hydrogen, and magnetic reactor was optimized to produce hydrogen conditions; Analyses the intermediate process of hydrogen, has been clear about the fermentation types; The PCR-DGGE, high-throughput sequencing of magnetic field on the characteristics of residual sludge anaerobic fermentation to produce hydrogen and the influence of the biological community succession, get the following conclusion:(1) During start-up time, when the hydraulic retention time was 12h, and magnetic group to achieve the most prolific gas rate, production rate and hydrogen content were 0.56 mol/mol · glucose,0.35 mol/mol · glucose and 80.3%, compared with no magnetic group, hydrogen production rate can be increased by 45%. Steady static magnetic field can effectively stabilize the reactor sludge quantity and pH, at startup stage basic maintained at 4.9-5.3. When the inlet COD is 5000 mg/L, magnetic group average removal rate of COD was 40.3%, the blank group can be increased by 37.9%.(2) When HRT was 8 h, under the condition of hydrogen for the added magnetic reactor to produce the best pH range of 4.0-4.5, the best carbon and nitrogen ratio is 40. Iron ions optimal dosing quantity is 200mg/L. Optimized for hydrogen production by anaerobic reactor eventually hydrogen production rate can be up to 0.35 mol/mol · glucose.(3) Two groups of liquid phase reactor end product was consistent, but the proportion of each product is different, no magnetic groups are mainly composed of butyric acid and acetic acid, and the product of magnetic group are mainly composed of ethanol and acetic acid, and the operating parameters optimized fermentation type did not change, that steady static magnetic field and is beneficial to the development of the ethanol type fermentation anaerobic microorganisms.(4) The original sludge in the reactor are mainly composed of filamentous fungi and bacteria, and magnetic field under the action of anaerobic sludge mainly bacillus and staphylococcus aureus, after add magnetic sludge together more closely. Each cycle of the community without too much change on the type, strip type did not have obvious change, but change the brightness of the strip. The added magnetic reactor run by high flux means 50 days of sludge samples determined the magnetic field were calculated for Firmicutes of biological communities, has obvious enrichment in the community the Firmicutes up to 64.7%. By identifying species found Ethanoligenens is the main advantage of a magnetic hydrogen production reactor strains, the total accounted for 30.0%, main effect for producing hydrogen production of ethanol. |
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