渗透反应格栅技术处理铀矿山酸性废水室内试验研究

东华理工大学硕士学位论文AbstractAcidic wastewater containing low level uranium mine production in China has anurgent need to solve the problem,to find cost-effective approach to uranium mining onenvironmental protection and sustainable development is of great significance.The"Permeable reaetive barriers"(PRBs)teehnology,a popular method of in situremediation of contaminated groundwater widely used reeently in Europe and Ameriea,is apassive treatment teehnology that removes dissolved contaminants from polluted water.Theapproaeh,compared to the earlier method,is charaetered with in situ remediation,goodlong-term performanee,many remediable contaminantsands and low costs.In this paper,with acidic wastewater containing low-level uranium from 721 as theresearch subject,five PRBs reactorswere designed with themixture of zero valentiron(ZVI),active carbon,zeolite as reaction media.The feasibility and effectiveness of treatingacidic wastewater containing low-level uranium from 721 by PRBs weretested.Theresearch results are as follows:1)PRBs reactor acid heap leaching of uranium mine waste water technology is feasible.Hybrid materials with different ratio of reaction column can make wastewater pollutioncomponents (U.Fe3+)to meet emission standards,after wastewater treatment incolumn Deffluent concentration of U longest national emission standards,oncentration of Fe3+afterwastewater treatment concentration up to the national emission standards in column E.2)PRBs as well as neutralize the acid,pH after treatment were 6 to 9,in line with nationalemission standards.3)Different ratio of reaction materials reflect different water-rock handling mechanism inthe treatment of pollutants of the Stage.ZVI in a stable period of time can restore the waterUO22+to UO2;Limestone and bentonite can neutralize acid,bentonit with a larger surface areaadsorbs the success of the Fe3+.When pH value increased to 4.38,UO22+will be hydrolyzed toUO2(OH)2,Fe3+conversion Fe (OH)3 precipitation,and thus achieve the effect of pollutioncomponents.4)ZVI as the main reaction medium,limestone and bentonite for the auxiliary reactionmedium PRBs in the mixed materials of different proportion,Reaction conditionsEh<260mV,5.2

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