铊是一种典型的剧毒重金属元素,毒性与汞相当。作为一种稀有元素,铊的自然环境背景值低,但极易富集并伴生于金属硫化物矿物中。我国含铊矿产资源丰富,多年来矿产资源粗放式的开发利用导致大量的铊等有毒元素进入表生环境,通过食物链蓄积放大,形成极大的环境隐患。笔者在总结传统的含铊废水物理化学处理技术的基础上,重点阐述了含铊废水微生物处理技术的原理和最新进展。传统的物理化学处理技术对去除微量铊有一定的作用,但难以达到当前我国GB 3838—2002《地表水环境质量标准》的要求(0.1μg/L)。微生物处理技术作为一种新兴的重金属废水处理技术,通过利用特定微生物对铊的氧化还原、吸附絮凝等作用,最为有效的深度处理废水中痕量铊。今后应重点开发微生物协同物理化学的含铊废水处理新技术,保证饮用水安全。
Thallium (T1) is a typical toxic heavy metal, with toxicity comparable to Hg. As a rare element, T1 has a low background level in nature, but can be enriched in some sulfide ores. There are abundant Tl-bearing-mineral resources in China. The excessive exploration over a long period has released into the environment a large amount of T1 and toxic elements likewise, thereby forming a dramatic environmental hidden hazard through bioaccumulation of food-chain. This paper firstly summarized the characteristics of traditional physical-chemical treatment technology for Tl-containing wastewater, and then focused on the principles and advances of microbial technology. The traditional physical and chemical treatment technologies have some effects in removing T1 from wastewater, but it is difficult to achieve China's current surface water limit of 0.1 μg/L. As a new wastewater treatment technology, microbial treatment technology can reduce T1 levels by specific microbial oxidation, adsorption flocculation and become the most effective way to remove T1 from wastewater. Therefore, it is high time to encourage research on combining microbial technology with traditional physical-chemical treatment technology to develop a thoroughly effective treatment technology for Tl-bearing wastewater, for assurance of drinking water safety.