ZHANG Xiao-na,HE Jia-li,MO Wan-qiu,et al.Cause of Standard-exceeding of Thallium in Water Supply Treatment Process and Its Control Method[J].China Water & Wastewater,2020,36(21 21):35-41.
Cause of Standard-exceeding of Thallium in Water Supply Treatment Process and Its Control Method
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第36卷
Number:
21 21
Page:
35-41
Column:
Date of publication:
2020-11-01
- Abstract:
- In a water supply treatment process of a pilot test with a design capacity of 120 m3/d, it was found that thallium concentration in the product water of clear water tank increased. The reason was that manganese oxides on the surface of sand filter material were enriched with thallium, and the manganese oxide fell off and entered the clear water tank during the backwash process. When the water quality changed, the concentration of fluorescent dissolved organic matters (such as aromatic proteinaceous substances and soluble microbial metabolites) increased. The organic compounds could complex with thallium in the sediment of the clear water tank, resulting in an increase in the concentration of thallium. Preoxidation technologies of potassium permanganate, monopotassium persulfate, chlorine dioxide and sodium hypochlorite had no effect on controlling thallium pollution. The repair experiment indicated that high concentration multi-organic acids (such as tartaric acid, malonic acid, citric acid and oxalic acid) had obvious effects on the removal of manganese and thallium on the surface of the sand filter. High concentration hydrochloric acid had a remarkable effect on the removal of heavy metal thallium on the surface of the sand filter. Soaking treatment with low concentration oxalic acid and high concentration chloride ion solution could significantly improve the removal efficiency of heavy metal thallium.
Last Update:
2020-11-01