Pilot Test Study On Medium Loading Cyclic Granulation Fluidized Bed Treatment Of High Algae

Cyclic granulation liquidized bed is a new generation of high-efficiency solid-liquid separation system integrating coagulation,clarification,precipitation and particle circulation developed by improving the internal structure of equipment on the basis of the practice of intensive coagulation engineering,which has the advantages of high treatment load,short hydraulic residence time,less floor space,strong water adaptability,etc.,and has self-granulation function,thereby enhancing the removal effect of turbidity organic matter and algae density.It can be seen that with the increase of the rising load in the liquidized bed,the removal effect of turbidity and organic matter is different,and it is found that the effluent effect is more stable when the rising load is 40m/h and 50m/h,when the rising load is 40m/h,the PAC dosage is 30mg/L,and when the PAM dosage is 0.8mg/L,the turbidity of the effluent is about 1.5NTU,and the removal rate of organic matter is about 40%.When the rising load is 50m/h,the PAC dosage is 30mg/L and the PAM dosage is 0.8mg/L.The turbidity of the effluent is about 2NTU,and the treatment effect for organic matter is about 42%.From the actual operation process of liquidized bed equipment in the formation of knots and fluoridation conditions,when the dosage of PAC is 20mg/L is the optimal dosage.The PAM dosage of 0.8-1.0mg/L is the most suitable.The cyclic agglomerated granulation liquidized bed is loaded with different mesh Microsecond when running,so that it can be fully liquidized in the equipment with different minimum rising loads.The maximum rising load is also different.The liquidized bed is loaded with 40-60 mesh micro-L,the rising load is 65m/h,the control PAM dosage is 0.8mg/L,and the PAC dosage is 10-30mg/L operation.When the experimental PAC dosage is 20mg/L,the effect is the best.The turbidity of the effluent is small.However,after continuing to increase the amount of PAC dosing,the effect has a downward trend,which may be caused by electrical neutralization,which is that the surface of the colloid has a positive charge,so that the destabilized colloid is stabilized.When loading 80-100 mesh of fine sand,the 40m/h rising load is optimal,and the turbidity of the effluent can reach about 1.5NTU.The removal effect of algae density gradually increased with the increase of PAC dosage,but when the PAC dosage was greater than 20mg/L,the removal effect of algae density and chlorophyll a gradually decreased.This is due to the increase of coagulant and the change of charge on the surface of the colloid,which is the change of the destabilization state of the colloid.Therefore,the removal effect and economic benefits are considered.When the dosage of PAC was 20mg/L,it had the best effect on algae density and chlorophyll a removal.Change the reaction time of the PAC by changing the length of the reaction tube.The reaction time of PAC was extended from 32s to 96s,and the removal effect of algae density and chlorophyll a gradually increased to about85%.By changing the length of the reaction tube to extend the reaction time,the removal rate of green algae is 90%,the removal rate of cyanobacteria is about 85%,and the removal rate of diatoms is about 88%.The dominant algae in the reservoir raw water are needle algae,brittle algae,chancellor.The removal rate of prolonged reaction time for needle algae is 93%,85%for brittle rod alga,and about 76%for chlorella.For the reservoir raw water,the dominant algae species have been improved to varying degrees.Under the condition that the magnetic particle rise load of circulating granulation liquidized bed was 30m/h,the algae density and chlorophyll a removal rate were92.18%and 91.12%,respectively.The dosage of potassium termagant significantly improved the algae density and chlorophyll removal.The density of protologue and chlorophyll a were 26 million/L and 25μg/L,respectively.The removal rate after increasing the dosage of potassium termagant increased from 90%and 86%to 93%and92%,respectively.The oxidant contact time was extended,and the algae density removal rate was stabilized from 93%to 95%.For chlorophyll a,it decreased from 3.77μg/L to 2.08μg/L.And its in fluent dominant algae,needle algae,pseudoscience,and chancellor.The removal rates were stable at 92.4%,91.6%and 88%,respectively.Increasing the dosage of sodium hypocrite for turbidity removal rate is from 75%-79%.For UV₂₅₄,the removal rate is increased from 25%to 42%.When the amount of Na Cl O was 3mg/L,the density of algae was about 2.353 million/L,and the removal rate was about 91%.The removal rate of chlorophyll Aincreased from 82%to 86%.Extended contact time increased turbidity removal from 78%to 86%and UV₂₅₄from 34%to 41%.Algae density removal rate increased to 91%.For chlorophyll a,it was reduced from3.26μg/L to 2.47μg/L.The removal rate is about 90.3%.