Study On Optimization Of Micro-vortex And Coagulation With Backflow Of Sludge Water

During the production and operation process of the water purification plant,a large amount of production waste water will be generated,especially for many small water plants and township water supplies in Jiangxi,which cannot be discharged into natural water bodies nearby to avoid to damaging the hydrological environment,it is particularly important to treat this part of wastewater.Due to the scale of the water plant and economic constraints,under the premise that a complete sludge disposal system cannot be configured,in the concept of"turning waste into treasure",it is a feasible way to return sludge water for reuse.At the same time,microvortex flocculation technology,as a new type of flocculation technology,encountered a series of problems in the process of application and promotion,and the technology needed to be optimized.The application of backflow of sludge water to the micro-vortex flocculation technology can not only save water resources and protect the ecological environment,but also promote the popularization and application of micro-vortex flocculation technology.Therefore,it is necessary to carry out optimization and optimization of micro-vortex flocculation technology.The research on the synergistic effect of backflow of sludge water should also study whether its effluent will cause safety risks.In this paper,focuses on the optimization of micro-vortex flocculation technology as the core of the research,and conducts a pilot study on the optimization of micro-vortex flocculation technology and the coordination of sludge water backflow.The research is mainly carried out in terms of micro-vortex flocculation parameters,sedimentation tank effluent indicators,safety analysis of sludge water after reflux,Zeta potential and changes in floc and molecular numbers in water,and low-temperature and low-turbidity water treatment effects.The main research results are as follows:1.Experimental research on optimization of micro-eddy current technologyBy controlling the dosage of the vortex reactor,the micro-vortex reaction time in the flocculation tank accounts for 3/4 of the total flocculation reaction time?at this time,the micro-vortex flocculation time is 8.1 min?,thereby achieving technical optimization.The results show that in this case,the effect of strengthening coagulation can also be achieved.Compared with the case where the entire reaction cell is transformed into a micro-vortex flocculation tank?the micro-vortex flocculation time is 10.8 min at this time?,it can also increase the maximum treated water volume by 25%and save 17%of the dosage.At the same time,this technology can achieve similar treatment effects under the same working conditions for water bodies that have been affected by different weather changes within a short period of time,and have strong adaptability,it can greatly reduce the Zeta potential,and at the same time,it can basically remove molecules with a particle size of 100?m or more in water.In this part of experiment,the optimal dosage is 25mg/l,the treated water volume is 6m³/h,and the mixing ratio of the vortex reactor is 3/4?Top 3/4?.2.Pilot-scale experimental study of micro-vortex synergistic sludge water backflowBased on the optimization experiments,the results of the pilot experiments of the micro-vortex folding plate and the sludge water backflow experiments show that the micro-vortex technology and the sludge water backflow technology enhance the coagulation effect significantly.The maximum amount of treated water was increased to 7m³/h,which was increased by more than 30%,and the saving rate was up to 20%,and all water quality indicators could meet the treatment requirements.Among them,for turbidity,color,CODMn and UV₂₅₄,the removal effect is relatively obvious.Under the optimal dosage,the turbidity of the sedimentation tank effluent can be stable below 3NTU,and the removal rates of COD_Mnn and UV₂₅₄54 are 55%respectively And 60%,and the best reflux ratios are between 2%and 4%.Due to the high ammonia nitrogen content in the raw water,the removal effect of ammonia nitrogen is not ideal.Although the maximum removal rate can reach more than 30%,it cannot be effectively reduced to the limit due to the coagulation process itself,With the increase of the reflux ratio,the concentration of ammonia nitrogen will also increase to a certain extent,so it is more appropriate to control the reflux ratio under 4%under a certain reflux concentration.The removal effect of total P is better,it can reduce the content by more than50%,and it will have a more significant effect at low dosage.The content of total P in the effluent will not be larger with the increase of reflux ratio Increase.Analysis of the metal composition of the effluent of the sedimentation tank by ICP-CES shows that the backflow of sludge water does not cause obvious enrichment of various metals,and the effect of removing metal components is not ideal.If the metal composition exceeds the standard,it is necessary to consider adding other corresponding processing devices.At the same time,the measurement results of the total number of bacteria and fecal coliforms in the water before filtration under different reflux ratios show that under a certain reflux concentration,when the reflux ratio is 0 to 4%,it will not cause a large number of microorganisms to accumulate.However,when the reflux ratio is greater than 6%,the number of microorganisms in the water body will increase by multiples,which may have an impact on subsequent processes,and the reflux ratio needs to be strictly controlled.The measurement of the zeta potential-level floc morphology in the water after the synergistic reaction shows that the zeta potential of the colloid can be further reduced by the synergistic reaction,and the effect is obviously better than the unilateral action of the coagulant.It can also form compact,large particles and small porosity flocs,which can greatly promote their adsorption and precipitation.It can be found that the removal rate for molecules with a particle size of 10?m or more is as high as 85%,which has a significant effect.The experiments under low temperature and low turbidity conditions show that micro-eddy current and sludge return water have better removal rate of turbidity,CODMn and UV254,and can deal with low temperature and low turbidity water better.3.Engineering application of micro-vortex synergistic sludge water backflow technologyAccording to the engineering application of the micro-eddy current synergistic sludge drainage backflow technology,it is known that its adaptability to small and medium-sized water plants,especially agricultural drinking water projects,can well solve most of the problems encountered in current drinking water projects.The transformation of the plant can also provide scientific advice and guidance.In summary,through the above research,it can be shown that within a certain reflux concentration,the micro-vortex synergistic sludge water reflux technology only needs to be in the proper reflux ratio and dosing ratio?the values are 4%and 3/4 in this article?.It can enhance the coagulation to a certain extent,improve the effluent quality of each structure,and ensure the effluent safety when the quality of the raw water is reliable,and further reduce the processing load in the filtration and disinfection stage.In addition,it can also adapt to the treatment of complex water bodies in extreme weather?such as low temperature and low turbidity water?.