Coagulation Performance And Composition Change In Hybrid Fruit Peel Coagulants

In this paper,based on previous research and development achievements of research group,that was using banana peels and orange peels,which were readily available,as raw materials to prepare hybrid peel?HFP?coagulant and anti-corrosion modification?AHFP?coagulant.Some AHFP were adjusted for acid-base before application and increased anti-corrosion dose,which were recorded as AAHFP and IAHFP respectively.With the extension of storage time within 0-50 days,these four agents were taken as research objects.The coagulation effects of humic acid simulated water and clay simulated wastewater were studied by jar tests;and the number and morphology of microorganisms,cell concentration and total number of colonies were analyzed by microscope,nephelometry and spread plate method,respectively;and the total sugar content was measured by anthrone sulfuric acid colorimetry.And characterization of zeta potential was used to analyze the coagulation mechanism.The water treatment effects of four agents fluctuated with the extension of storage time:?1?In terms of turbidity and chroma removal rates,the trend of two removal rates of the same kind of raw water were the same with the same agent.The turbidity and chroma removal rates of AAHFP and AHFP for two kinds of simulated waters were both stable first and then experienced two cycles of fluctuation,and the former's turbidity and chroma removal rates basically reached 80%and 70%,respectively,which was significantly better than that of AHFP.The two removal rates of HFP for two simulated waters dropped first and were the most unstable.The two removal rates of IAHFP were lower than that of AAHFP;?2?The UV₂₅₄removal rate of four agents to humic acid simulated water fluctuated frequently from 35%to60%,and the difference was small,and the UV₂₅₄54 removal rate of clay simulated water was negative;?3?COD removal rate of four agents to humic acid simulated water was lower than that in clay simulated wastewater.The pH,color and character,microbes,and organic content of HFP changed significantly earlier than those of the other three agents.Except for pH,the changes in the components of AAHFP and AHFP were basically the same and synchronized.In 0-50 days,the changes of pH,color and character of the same agent were basically synchronized.The pH values of HFP and AHFP both decreased to acidity and then rose to alkalinity and the color of HFP and AHFP became lighter.0 day,the p H of HFP and AHFP were close to 11 and were dark brown liquid with natural fragrance,which were reduced to the lowest at 6 d and 25 d,respectively 5.06 and 5.62,and they became light brown and viscous.The pH value of HFP and AHFP rised with the increase of odor,wall hanging phenomenon and white film.However the pH values of IAHFP were greater than that of HFP and AHFP,and had always remained light brown.With the extension of storage time,the microbial quantity and morphology observation,OD₆₀₀ value and total number of colonies of the same agent all increased and the changes were basically consistent.The number and size of microorganisms in agent increased,and there were obvious bacterial aggregation phenomena,and various microbial forms.Bacteria,yeasts and molds were produced in the agents,and the maximum dilution factor of HFP,AHFP,and IAHFP was 10¹¹,10¹³,and 10¹³,respectively,which were basically consistent with the change process of OD₆₀₀:the OD₆₀₀ value of HFP first increased and stabilized at the earliest,and reaching the maximum value of 3.21 on 37 day;the OD₆₀₀00 value of AHFP and AAHFP stabilized within 0-23 days,and gradually increased to 4.2 after 23 days;the OD₆₀₀value of IAHFP decreased first and then increased to 4.1.With the extension of storage time,the total organic content except IAHFP increased slightly,and the total organic content of HFP,AHFP,AAHFP and the total sugar content of the four agents decreased in a fluctuating manner.In 0-25 days,the total sugar content of AAHFP and AHFP was higher than that of HFP,and the total sugar content of the four agents was basically below 1 mg/mL and the difference was extremely small after 25 days.The total organic content of IAHFP was mostly higher than that of AHFP and AAHFP,and that of HFP was the lowest.The water treatment effect and composition of the four agents changed with the extension of storage time.Water treatment effect and composition of HFP changed first and were at a disadvantage.AAHFP had the best water treatment performance on the two kinds of simulated water,and compared with AHFP,the turbidity and chroma removal performance of were obviously improved,while the UV₂₅₄ and COD removal performance were not significantly improved,and the effect of acid-base regulation on composition change was small,and there was basically no difference between the change curve of each component of AHFP.The water treatment effect and composition of IAHFP only improved slightly at some times.Changes in the components of the same agent affected each other and were related.The mechanism of coagulation was mainly based on the adsorption and bridging effect of the active groups contained in organic substances,and supplemented by the rewinding of the net,and the mechanism of coagulation of AAHFP also included the charge neutralization.