Effect Of Carrier On Microbial Communities Structure During Biochemical Treatment Of Acrylic Fiber Wastewater

The main components of acrylic wastewater contain nitriles,phenol,N,N-dimethylacetamide,alkanes,methyl acrylate,aromatic hydrocarbons,mercaptan,sodium methallylsulfonate,etc.It has been recognized one of the refractory organic wastewater due to its high pollutant concentration and complex composition.During the long-term research of the 11 th Five-Year national water pollution control major special project "acrylic wastewater biochemical treatment technology development and engineering demonstration" and the 12 th five national water pollution control major special project " Biological treatment technology and equipment for enhanced removal of organic matter and ammonia nitrogen from acrylic waste water",we found that carrier has a good promoting effect on the biochemical treatment of acrylic wastewater.In order to profoundly reveal the impact of different carriers on the biochemical treatment of acrylic wastewater.In this paper,the traditional activated sludge aeration tank,the baffled microbiological immobilization biochemical pool,and the SBBR experimental device with different carriers of Jilin Chemical Fiber Wastewater Treatment Plant are used as the targets.Illumina MiSeq high-throughput sequencing method is used to analyze the characteristics and changes of microbial community structure during the treatment of acrylic fiber wastewater in different reactors,and to explore the influence of different carriers on the microbial community structure during the biochemical treatment of acrylic fiber wastewater.It provides technical reference for acrylic fiber wastewater treatment,and also provides technical support for actual engineering transformation and provides reference for similar research.(1)In the traditional activated sludge aeration tank,from L1 to L4,the diversity of the overall microbial community structure is not significant.Among them,L2 has the highest microbial richness and diversity,while L3 is the lowest.At the phylum level,Proteobacterta,Planctomycetes,Bacteroidetes,Thermi are the dominant bacteria in traditional activated sludge aeration tank.At the genus level,Meiothermus,Paracoccus,Diaphorobacter,Nitrosomonas,Rhodobacter,Thauera are the main organic and ammonia nitrogen degrading bacteria in the traditional activated sludge aeration tank.The relative abundance of Meiothermus in all four samples are above 18%,it plays an important role in the degradation of organic matter in acrylic fiber wastewater.(2)In the compartments of the baffle microbial immobilization biochemical pool,the microbial community richness and diversity of the fourth compartment is the highest,and the first compartment is the lowest.At the phylum level,Proteobacteria,Bacteroidetes,Chloroflexi,Planctomycetes,Thermi,Chlorobi,Acidobacteria are the dominant bacteria in the baffled microbial immobilization biochemical pool.At the genus level,the microbial community structure in the fourth and fifth compartments tends to be stable.Its main dominant bacteria are Rhodanobacter,Diaphorobacter,Nostocoida,Mucilaginibacter,Candidatus brocadia,Aridibacter,Gemmata,Aquicella.The relative abundance of Aridibacter in the second and fifth compartments are above 5%,it may have special degradation capacity for polymerized organic matter in acrylic fiber wastewater.(3)The microbial community richness and diversity of baffle microbial immobilization biochemical pool are higher than in traditional activated sludge aeration tanks.At the phylum level,Acidobacteria and Chloroflex are the new dominant bacteria in baffle microbial immobilization biochemical pool.At the genus level,Aridibacter,Nostocoida,Mucilaginibacter,Rhodanobacter,Thermomonas,Gemmata,Chitinophaga,Desulforhabdus,Aquicella,Nitrosospira,Bosea,etc.are accumulated or Emerging Bacteria in baffle microbial immobilization biochemical pool.Most of these bacteria are related to organic degradation and denitrification.It can be seen that the addition of organic porous carriers can increase the diversity of microbial communities.Organic porous carriers have little effect on the total relative abundance of denitrifying bacteria,but can significantly improve the diversity of denitrifying bacteria community structure.(4)In the SBBR reactors with different carriers,the microbial community richness of reactor with organic porous carriers is the highest.And the microbial communities uniformity of reactor with "organic porous carrier and sponge iron" is higher,resulting in higher diversity.At the phylum level,the relative abundances of Proteobacteria and Planctomycetes are all above 50%,and they are the major contributors to the biodegradation of organics in acrylic wastewater.At the genus level,the S4 reactor with "organic porous carrier and sponge iron" has a superior microbial community structure.The main dominant bacteria are Gemmata,Planctomyces,Aridibacter,Fluviicola,Phycisphaera.The total relative abundance of Gemmata and Planctomyces in S4 reactor is 24%,the good treatment effect of S4 reactor is closely related to its metabolic growth.(5)The addition of carriers can significantly increase the relative abundance of denitrifying bacteria in each SBBR reactor,but different carriers have different effects.Both the organic porous carrier and the "organic porous carrier and sponge iron" composite carrier can promote the growth of denitrifying bacteria,the relative abundance is greatly increased,and the composite carrier is more selective to denitrifying functional bacteria.