Research On Synchronous Removal Efficiency Of Iron And Barium From Cold Mineral Water Rich In Strontium By Aeration

The natural metasilicate-type cold mineral water source rich in strontium originatingfrom The Five connective Lakes Region in Heilongjiang Province of China has very highmedicinal value.The water contains both barium and strontium.Barium is very toxic tohuman body, while strontium is one of the trace elements beneficial to human body.Ourobjective is removing barium meanwhile retaining strontiu, however, belonging to thesame main group, the chemical properties of barium and strontium are similar to eachother. They are likely to be removed at the same time in the water treatment process. Atpresent most water treatment processes focus on common material removal, but fewresearches are carried on uncommen toxic ions such as barium. In addition, theseresearches almost ignored retention of beneficial elements.Whether traditional watertreatment process can remove barium meanwhile retaining strontium is still unknown.Only limited researches on removal of barium pollution from aqueous are reported athome and abroad,and these researches are difficult to meet the actual need of removingbarium meanwhile retaining strontium. With the quality of natural mineral water isbecoming more and more concerned, more safe and effective water treatment method ontreating mineral water should be explored.This research was studied on The Five connective Lakes cold mineral water rich instrontium as the background. This study investigated the removal of harmful elements asiron and barium and retaining of beneficial elements like strontium with the method ofsimulating the traditional mineral water treatment process aeration, sedimentation andfiltration. This study identified several water treatment process parameters which shouldbe focus on by investigating the influence of factors such as gas-water ratio, the initialcontent of each ion, the content of bicarbonate, pH at the end of reaction, the intensity ofaeration and the content of iron. To inspect the feasibility of this method, experimentswere carried out on the water samples collected from The Five connective Lakes. Thisresearch provided an important reference for the design of practical mineral watertreatment process. In addition, the study was carried on the mechanism of removal of ironand barium synchronously meanwhile retaining strontium with the method of aeration.Experimental results showed that in the aeration process of each system, the contentof Ba changed attached to the content of Fe, and gradually be eliminated during aerationas precipitate, and the content of the Sr almost stayed the same. So this method generallyremoved iron and barium and retained strontium at the same time. In each reaction system,content of iron and barium came to an equilibrium at the20th minute, in our words, at thepH of7.5or so. Aeration with Oxygen has no obvious advantage on the progress of removal iron and barium synchronously meanwhile retaining strontium. As a result, inorder to reduce the cost of water air is the recommented gas source. When the pH valueis greater than8.1at the end of aeration, the content of barium and strontium falled steeply.To retain maximum content of strontium, suggested that keep the pH value around8.0atthe end of reaction. When the initial content of the iron increased up to60mg/L, strontiumappeared a same decrease trend with barium. The maximum content of barium removedfrom water can be measured by a formula knowing the content of Fe in the water.Results of mechanism exploration show that, the mechanism of removal iron andbarium synchronously with aeration may due to adsorbing, which means flocs of ironhydroxide absorbed barium ion. And this adsorption conforms to the BET adsorptionisotherm model. Flocs of Iron hydroxide adsorbed ions with larger radius more easily.When PH increased up to8.0or above, barium ion and strontium ion were both removedfrom aqueous in the form of carbonate precipitation.