Research on the possibility treatment of radioactive substances in the water waste titanium exploitation by vetiver grass and the reed

Abstract: Direct sewage from titanium mines containing radio nuclides can contaminate soil and water seriously affecting human health as well as ecological balance. In recent years, the method of using flora in order to treat radioactive pollution is being investigated due to low investment costs, safety and environmental friendly. Therefore, the intention of this study is to evaluate the ability to remove radio nuclides 232U and 238Th in titanium mining wastewater by two types of vetiver grass and reed plants in pilot-scale. Result of the experiements has showed that both Vetiver grass and Reed grow well in the condition of flooded environment with the radioactive wastewater, these plants lead to the best growth with the height, biomass rising to 90% and 43.4% for Vetiver grass as well as 22.2% and 8% for Reed respectively after the experiment terminated.
After 15 days of planting uptake efficiency of 238U of Vetiver grass reached 59% higher than that for Reed of 48%. However, with 232Th nuclide, the uptake efficiency of Vetiver grass was 79.7% lower than that for Reed of reached 86.5%. Total alpha and beta were also quite well-modeled with a 90% processing efficiency for both Vetiver and Reed models. Specifically, wastewater treatment efficiency with Vetiver model for total alpha is 99.67% and beta is 95%; Reed model for alpha is 99.6% and beta is 91.3%. The output effluent meets the standard of Class A according to QCVN 08-MT: 2015 / BTNMT. Model of radioactive sewage treatment by Vetiver grass and Reed presents a good treatment efficiency in a simple operation with the prospect of applying in practical conditions for wastewater treatment in the Titanium mining industry.
Keywords: Vetiver, Reed, Titanium mining