Preparation And Performance Of A Hybrid Fruit-peel Coagulant

The banana peel and orange peel were used as raw materials to prepare the Hybrid Fruit-Peel（HFP）Coagulant through orthogonal experiment,and the final preparation method was determined through the study on the stability of HFP.HFP were characterized by scanning electron microscopy（SEM）,Fourier transform infrared（FTIR）spectrometer and nanometer particle size analyzer,respectively.HFP was used to treat humic acid simulated water and organic simulated water treatment to investigate its coagulation effect.Finally,the mechanism of HFP was simply analyzed.（1）Based on the results of orthogonal experimental,the preparation conditions of HFP were determined:the mass ratio of banana peel to orange peel is 3:1,the water bath time and temperature were 10 minute and 60℃,respectively.The adding amount of stabilizer was selected as 1.695g/L according to the single factor test.（2）Turbidity and color removal by HFP were measured in treating humic acid simulated water,compared with that by BBP which is a kind of coagulant prepared from pure banana peel.The influence of dosage,raw water pH,settling time,raw water turbidity,raw water color,and raw water temperature on the coagulation effect of HFP were investigated.The turbidity and color removal rate of HFP was 95.6%and 88.1%at suitable dosage,respectively,compared with that of BBP was 84.6%and 78.6%,respectively.However,the coagulation effect of HFP was significantly better than that of BBP at lower dosage.In the range of pH from 3 to 11,the turbidity removal rate of HFP was stable at around 95%,with the increasing of pH,the color removal rate decreases continuously and reaches the maximum value of95.5%when the pH value is 3.And in the range of pH from 3 to 11,the turbidity and color removal rate of BBP has been reduced,and the turbidity and color removal rate reached92.4%and 93.4%when pH was 3,respectively.When the precipitation time is 5min,the turbidity and color removal rate of HFP was 89.2%and 85.6%,respectively,compared with that of BBP was 67.89%and 67.7%,respectively.When the raw water turbidity at lower values,the turbidity removal rate of HFP and BBP was 80.9%and 53.2%,respectively.When the raw water color at lower values,the color removal rate of HFP and BBP was 44.2%and4.3%,respectively.The liquid HFP was solidified and used for coagulation experiments,at the same dosage,the coagulation effect of liquid HFP is always higher than that of solid HFP.With the increase of dosage,the coagulation effect gap between solid HFP and liquid HFP was narrowing.（3）COD and UV₂₅₄54 removal by HFP were investigated in the treating organic simulated water,compared with that by BBP.Research results show that,the COD removal rates of both HFP and BBP did not exceed 45%,with the increase of dosage,the removal efficiency of the two coagulants showed an overall downward trend.HFP and BBP had little effect on the removal of UV₂₅₄ in organic simulated water,moreover,with the increase of dosage,the value of UV₂₅₄ in organic simulated water presented a nearly linear increasing trend.（4）HFP is sugary and viscosity,the surface of HFP was roughness and the surface area is large.The main ingredients of HFP include protein,cellulose,lipid,polysaccharide and other substances.The coagulation mechanism of HFP is adsorption bridge or adsorption neutralization.The coagulant and the impurity particles are mutually adsorbed by hydrogen bonding or electrical neutralization,and are condensed into flocs by bridging in the water.And then settled to remove the impurity particles.