| Ranked second in industrial waste discharge,Papermaking waste water discharge in our country accounts for 16.7% of industrial wastewater discharge.the development of the paper industry and our living environment are seriously effected by its characteristics such as emissions,complex contaminants,difficult treatments and etc.It is very urgent to build the waste water treatment system of low-cost,high-efficiency and stable.Internal circulating anaerobic reactor with low-cost and stable effect,is widely used in the paper industry currently.In this paper,we regard the Internal circulating anaerobic reactor of a papermaking factory in Fujian as a research object and analyze the relevant data of waste water treatment process.At the beginning of the reactor operation,the influent Volatile Fatty Acid(VFA)seriously effected by the Chemical Oxygen Demand(COD)removal rate.The removal rate of CODCr fluctuated from 43% to 77%.After running about75 days,the buffering power of influent p H and VFA was enhanced,The removal rate of CODCr varied from 65% to 74%;After running about 9months,the ratio of volatile suspended solid(VSS)/total suspended solid(TSS)in sludge has a significant downward trend.Combined with The XRD and FTIR analysis,the inorganic salt Ca CO3 was gradually deposited in the sludge during the anaerobic operation process.Finally,the VSS/TSS was decreased and the activity of anaerobic granular sludge was effected by the sedimentation of inorganic salt Ca CO3.Through the acclimation of anaerobic granular sludge,the highly productive hydrogen and acid-producing bacteria DW01 were separated.We analyzed the DW01 strain by using the 16 S r DNA sequence analysis,as a result,the DW01 was a new species of Raoultella.The hydrogen production was measured under different carbon sources,nitrogen sources and substrate concentrations.The hydrogen production was also measured under different carbon sources,nitrogen sources and substrate concentrations.The results showed that the specific hydrogen production rate of DW01 strain was 1.28 mol-H2/mol under the condition that the initial p H was 7,15 g/L glucose as the carbon source and 0.883 g/L L-glutamic acid as nitrogen source.Then,the single factor test was used to determine the initial p H value,L-glutamic acid concentration and inoculation amount.The fermentation conditions of DW01 strain were designed by Central Composite Design(CCD).Used the Response Surface Methodology(RSM),we got the optimum fermentation conditions that the initial p H,concentration of L-glutamic and inoculation amount was 5.8 ? 4.3 g/L and 15%.Under these conditions,the cumulative hydrogen production was 2088.5 m L/L,which was 29.5% higher than that before optimization.Finally,we examined the DW01 strain on the influence biogas production of anaerobic granular sludge which sludge age of 70 d,180 d,335 d and 510 d.Under the optimal growth condition of DW01 strain,the same amount of anaerobic granular sludge was inoculated into batch fermentation experiment.The results showed that the biogas production was different from anaerobic granular sludge with different sludge age.When the sludge age was 180 d,the sludge biogas activity was the best,the production was 4242.7 m L.Under the same conditions,the fermentation experiment was carried out after adding DW01 strain.The results showed that the sludge with the age of 335 d was increased by15.2% compared with the untreated DW01 strain.In this paper,the internal environment of anaerobic reactor is controlled by strengthening the acidogenic bacteria,the activity of sludge in the stable period is improved,so we find a new way to prevent the deposition of Ca CO3 in the sludge. |
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