Preparation Of Coated Adsorbent Belt And Removing Dyes Wastewater By Continuous Gas-assisted Adsorption

Adsorption separation technology is widely used in wastewater treatment due to its advantages such as low cost and simple process.In order to solve the problem that the technology is difficult to be continuous and cannot be applied to the suspended wastewater system,the research group has proposed to replace the belt adsorbent with the particulate adsorbent and coupled with the air flotation technology,and established a gas-assisted belt adsorption separation method.In order to further improve this brand-new method,this paper has carried out in-depth research on the preparation technology,desorption method and application system expansion of the adsorbent.Taking the dye wastewater as a model,this paper proposes and establishes the preparation method of the coated adsorbent belt and The method is extended to continuous and simultaneous removal of composite dyes in wastewater.The main research contents are as follows:(1)Adopting the non-woven fabric as the base epoxy resin coating method,the preparation method of the coated adsorbent tape was established,and its adsorption and desorption performance was investigated and optimized.The removal rates of the prepared coated belt adsorbent to crystal violet,malachite green,methyl orange and Congo red were 96.30%,99.39%,7.48%and 63.63%respectively.Taking crystal violet as the object,the adsorption zone can reach adsorption equilibrium within 20 minutes,and the removal rate is 96.30%.The adsorption process conforms to the Langmuir model,and the maximum saturation adsorption capacity is 833.33 mg/m~2.The elution rate was 30%by volume of ethanol,and the elution rate was 10.03%in 5 minutes.And the desorption rate was 81.75%in 10 minutes during hot steam desorption.(2)The performance of gas-assisted belt adsorption separation and removal of single-component crystal violet dye suspended wastewater under intermittent feeding was investigated,and the influence of initial concentration,time,p H,gas velocity,ionic strength,and surfactant on the process was obtained.And kinetic analysis of the separation process.Under optimized conditions,100 mg/L crystal violet and 250 mg/L sludge wastewater can be treated,and the removal rate can reach more than 90%at 87minutes,and no sludge was found.When using hot steam desorption,the removal rate can reach 96.28%,compared with 30%volume fraction of ethanol elution,the removal rate is only reduced by 3.69%.(3)The performance of continuous removal of crystal violet dye in wastewater in a continuous gas-assisted belt-type adsorption separation device was investigated.Based on the steady-state time,the regulation of the initial concentration,gas velocity,p H,and ionic strength on the process was investigated.Under optimized conditions,the continuous treatment of crystal violet wastewater with an initial dye concentration of30 mg/L and sludge concentration of 250 mg/L has a removal rate of over 90%.(4)It is proved that this method can be directly applied to the continuous and simultaneous removal of crystal violet and Congo red composite dye wastewater.First,the performance of the adsorption and desorption of the composite dye wastewater by the belt adsorbent was investigated and optimized,and then the key parameters of the eluent,mass ratio,gas velocity,p H and chlorination of the composite dye wastewater were obtained by intermittent gas assisted belt adsorption The influence law of sodium concentration on the removal effect.Under optimized conditions,the removal rates of crystal violet and Congo red were 99.72%and 92.34%,respectively.On this basis,the continuous process was further studied.Under optimized conditions,for the 20 mg/L crystal violet and 20 mg/L Congo red composite dye wastewater,when the feed flow is30 m L/min,the gas velocity is 80 m L/min At that time,the removal rates of Congo red and crystal violet were 92.56%and 95.17%,respectively.