Adsorption Of Reinjection Of Produced Water From Tight Gas Under Methanol Conditions

Ba²⁺,benzene,toluene and ethylbenzene（BTEX）are common pollutants in produced water.Improper treatment of produced water will cause great harm to soil,groundwater and other environment.The treatment technologies of produced water at home and abroad include simple treatment and reuse,discharge after treatment,and deep well injection（reinjection）.Among them,deep well injection（reinjection）technology has been widely used in the United States,and there is little application of this technology in China and lack of risk research.This thesis is divided into three parts.The first part and the second part are about the adsorption of Ba²⁺,benzene,toluene and ethylbenzene on Chang 3 gray rock powder respectively.The third part is the application of The Geochemist’s Workbench（GWB）software for the numerical simulation of Ba²⁺,benzene,toluene and ethylbenzene in the reinjection formation.Through the adsorption kinetics experiments of Ba²⁺on Chang 3 gray rock powder under different conditions,the influence of different variable conditions on Ba²⁺adsorption on Chang 3 gray rock powder was determined,and the experimental results were matched with different adsorption kinetics models to determine the applicable model of the adsorption process and explain the mechanism of the adsorption process.It is found that the adsorption kinetics of Ba²⁺on Chang 3 gray rock powder accords with the quasi second-order kinetics model.The adsorption process may include surface complexation,intra particle diffusion and other processes.At the same time,methanol has little effect on the adsorption process at a relatively low concentration.Through the adsorption isotherms of benzene,toluene and ethylbenzene on Chang 3gray rock powder,the adsorption capacity of benzene,toluene and ethylbenzene on Chang 3 gray rock powder was determined.Through the single component adsorption isotherm experiment,it is found that under the same conditions,the smaller the solubility of organic matter in water,the more conducive to its adsorption on the Chang 3 gray rock powder;through the adsorption isotherm experiment of mixed components,it is found that the adsorption of mixed component solution is more complex,one part is the distribution of three compounds in the rock organic matter,the other part is its adsorption on the mineral surface At the same time,methanol can promote the adsorption of benzene,toluene and ethylbenzene on Chang 3 gray rock powder.The adsorption and migration of Ba²⁺,benzene,toluene and ethylbenzene in the formation with water flow are simulated to predict the adsorption and migration of Ba²⁺,benzene,toluene and ethylbenzene in the formation.The results of numerical simulation show that Ba²⁺can be adsorbed almost completely,and Ba²⁺does not break through the boundary,while benzene,toluene and ethylbenzene are difficult to be adsorbed completely,and finally can break through the boundary.Methanol can enhance the adsorption of benzene,toluene and ethylbenzene,and hinder their migration in the formation,but it has no significant effect on the adsorption and migration of Ba²⁺ in the formation.