Status and progress of treatment technologies for arsenic-bearing groundwater

This paper is the result of groundwater geological survey engineering.

Objective There are hundreds of millions of people in more than 70 countries in the world facing the threat of high arsenic groundwater. Long-term drinking high-arsenic groundwater will lead to chronic arsenic poisoning, cancer, and seriously endanger health. The distribution of arsenic concentration in groundwater is the result of multiple factors including sedimentary environment, meteorological hydrology, mineral environment, and human activities. Therefore, it is necessary to start from the different physical and chemical properties of arsenic and select appropriate and targeted treatment technologies.

Methods Based on the current pollution status of arsenic-bearing groundwater, the current situation and progress of arsenic-bearing groundwater treatment were analyzed by comprehensively considering various factors such as removal amount, treatment cost, remediation rate, and reversibility.

Results This study comprehensively introduces the arsenic-bearing groundwater treatment technology, covering the research results of chemical oxidation, coagulation- sedimentation, adsorption, ion exchange, membrane technology and bioremediation, and shows the removal effect of different types of treatment methods on high- arsenic groundwater. In order to provide a meaningful reference for the comprehensive treatment of arsenic-bearing groundwater, the internal mechanism and the latest optimization measures for the technology are summarized, and the development trend of the arsenic- bearing groundwater treatment technology is prospected.

Conclusions The current arsenic-bearing water treatment technology has many defects, and the generated waste or sludge may become a potential source of secondary pollution. Therefore, to better protect our environment from As, new mixing techniques and safe disposal methods for As- laden waste/sludge are required. The lack of awareness of drinking water safety and availability in remote areas also presents challenges for arsenic management, so an affordable, easy-tobuild technology that operates at the community or household level is needed to address the problem.