Anaerobic Acidification-aerobic And Double Photosynthetic Bacteria Fluidized Beds To Treat High Concentration Organic Wastewater

A study on treatment of the ferment wastewater of marigold processing with high concentration ammonia and high concentration organic matter by using photosynthetic bacteria(PSB)process was conducted.The PSB process was divided into 2 stages,namely,pretreatment by soluabilization,main-treatment with PSB.This paper focused on the choice of optimal processing parameter for soluabilization stage and PSB stage,mechanism of removal or conversion of nitrogen Bio-species of PSB phase was investigated,and cost-effectiveness analysis of the treatment marigold wastewater by PSB process was tried.On the basis of the experiment,the optimum operating conditions for soluabilization phase were selected as follows:pH 6.0,hydraulic retention time(HRT)12h,and volumetric loading rate 120kgCOD/m³Â·d.Under this optimum conditions and at a COD concentration of 60000 mg/L and BOD₅ of 31200 mg/L in the influent,the average removal rates of COD and BOD₅ were 21.02%and 18.61%,respectively,and the reduced rate of sulfate was 52.5%.The total volatile acid(TVFA),the ratio of BOD₅/COD and TFVA/COD of effluent reached 32423mg/L mg/L,0.56and 0.714,respectively,which were favorable to the following PSB stage.The experimental results showed that the optimal operating conditions for The first photosynthetic bacteria fluidized bed is backfilled with light carbon residue with porous, the second one is backfilled with activated carbon,and the agitate way are mechanical agitated and mechanical agitated combined with air agitated,stable operation for 40 days.The resulted shows,after diluted to 8000～12000mg/L by domestic sewage enter into fluidized bed reactors and then stay for 48h under anaerobic in the daytime microaerobic in the evening condition the COD decreased to 295.8～420mg/L,more than 96.2%COD removals was achieved so as the removals of NH₃-N and TN were 97.6%,71.3%.Micrographs and the results of counting of microorganism indicated that the dominant level of PSB was high and mixed PSB strain existed in the reactor of PSB stage,which supplied important biological foundation of denitrification and desulfurization of PSB.Different kind of packings are backfilled with different phase,PSB1 is backfilled with light carbon residue with porous and its high Porosity is conteted to Attachment space for photosynthetic bacteria;Photosynthetic bacteria will release water-soluble pigment and the activated carbon has high Efficiency in water-soluble pigment absorbted.So the removals of Turbidity caused by water-soluble pigment is 62.7%. used for the treatment marigold wastewater.Not only can PSB process make treated effluent meet discharge standard but also it needed less capital and operating cost.Therefore PSB process was considered as a feasible one in practice.The experimental results,including the choice of the optimum processing parameter and the control of optimal operating conditions for soluabilization and PSB phase,the mechanism of removal or conversion of nitrogen,etc,was significant for the application of PSB process to the treatment of high concentration organic wastewater on the large scale.