Enhancing The Adsorption In The Bulk Liquid By Using Foam Separation Column Fitted With Baffles

There are the two critical steps in foam separation:interfacial adsorption and foam drainage. Interfacial adsorption and foam drainage are the two essential steps affected the enrichment ratio and recovery percentage. Moreover, interfacial adsorption has an essential effect on foam drainage. Therefore, it is necessary to pay much attention to the study on enhancing interfacial adsorption in foam separation.In addition to physical properties of the feeding solution and operation conditions, column structures are very important for enhancing interfacial adsorption during the process of foam separation.It is necessary to intensify the study on enhancing interfacial adsorption by developing the internal component in the bulk liquid phase of foam separation column for further understand of foam separation and promote the industrialization of such resource-conserving and environment-friendly technology.In this work, a simple type of foam separation column with the baffle internal component (BIC) in the bulk liquid phase was developed in order to enhance interfacial adsorption, using SDS (sodium dodecyl sulfate) and soy whey wastewater as the model system. With decreasing tray spacing from40mm to10mm and the chord length of the baffle from45mm to29.8mm, both adsorbed mass flux and surface excess significantly increased. For SDS, the optimal volumetric flow of the air is250mL/min, the optimal concentration of positioning is0.6g/L, the optimal baffle spacing of baffles is10mm, the optimal chord length of the baffle is40mm. Under the optimal conditions, a surface excess of6.2×10-5g/cm2and an adsorbed mass flux of0.0058g/min were obtained with the BIC of10mm in the baffle spacing and29.8mm in the chord length of the baffle.In the soy whey wastewater model system, the optimal concentration of pH is6, both adsorbed mass flux and surface excess in the experiment column were higher than those in the control column. With the increase of the volumetric flow of the air from150to550 mL/min, both adsorbed mass flux and surface excess in both the columns decreased and approached to an asymptotic value. With decreasing tray spacing from40mm to10mm and the chord length of the baffle from45mm to29.8mm, the adsorbed mass flux and the surface excess significantly increased. Under the conditions of the proteins concentration in the bulk liquid phase1.8g/L and the volumetric flow of the air250mL/min, the baffle spacing of baffles10mm, the chord length of the baffle40mm, sparger aperture0.25mm, pH6, a surface excess of3.1×10-7g/cm2and an adsorbed mass flux of0.0076g/min were obtained with the BIC of10mm in the baffle spacing and29.8mm in the chord length of the baffle and they were193%and153%higher than those obtained without the BIC. Enrichment ratio of protein increased while its recovery percentage decreased. Enrichment ratio of the proteins in the experiment column was significantly higher than that in the control column.