| A large mount of molasses alcohol wastewater(MAW)is produced during fermening molasses to produce alcohol,which contains high concertation organic and is hard to handle.It posed seriously to environmental problem on corporation and surroundings.We used self-made simple anaerobic reactor to treat molasses alcohol wastewater with two kind of feeding modes during the experiment,pulse feeding model and semi-continuous feeding model.Then we compared with outcome of two kinds of craft and analyzed microbial community dynamic,for finding a effective and economic treatment craft and paving the way to treat molasses alcohol wastewater.Our study was under pilot scale test and fermentation temperature was room temperature.We used self-made anaerobic reactor—operating volume was 4 L to treat molasses alcohol wastewater with two kinds of feeding models during the entire experiment,pulse feeding model(feeding substrate within 10 min)and semi-continuous feeding model(feeding substrate within 22 h),without adition of extra nutrient substance.Each treatment set three repeat.The inital organic loading rate(OLR)of reaction was 1 gCOD/(L·d),during the test by increasing the concentration of wastewater to increase the OLR.In the study,at the first phase of the trial we used mixed waste molasses acohol wastewater and manure waste as substrate,and the second phase sole molasses alcohol wastewater as substrate.Research data show that the OLR during 1-9 gCOD/(L·d),the hydraulic retention time of 8 days,at different feeding methods,the effect of treatment seems similar.When the OLR is 3 gCOD/(L · d),sCOD removal rate was the most high,semi-continuous feeding mode sCOD removal rate was 73.58%± 1.7%,the other was74.94%± 0.45%.When the mixed wastewater was used as the substrate,the OLR was 8 gCOD/(L · d),and the daily gas production was the largest.The maximum gas production in the first injection mode is 10650 mL ± 220 mL,and the maximum gas production in the semi-continuous injection mode is 10410 mL ± 120 mL.But they are not good in cleaning color.The microbial community structure at different stages was elucidated by high throughput sequencing and biometric analysis.Q30 is greater than 96%,proving that the sequencing results are more reliable.The dilution curve is close to smooth,indicating that the data is reasonable.After OTU clustering analysis,the number of OTUs for B1 and B2 is 2063 and 1950 respectively.The number of OTUs for C1 and C2 is 1739 and 2071,respectively.The number of OTUs for D1 and D2 is 1874 and 1769,respectively.The number of OTUs for El and E2 is 1331 and 1704,respectively.The results of species annotation indicate that the abundance of the two species is basically the same at the level of the phylum and genus,except that the species with abundance are different in different groups.The effect of the reactor on the wastewater treatment is simlar to that in the different injection mode,which indicates that the microbial community is redundant.Compared with the initial sludge,the relative abundance of the Proteobacteria and Smithella decreased,while the relative abundance of Sedimentibacter increased a lot in E phase. |
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