In elementary form, mercury is a danger to humans and the environment. But chemically bound to sulfur it loses its toxicity and can be disposed safely. The process which transforms the highly toxic metal into an unproblematic red powder is called mercury stabilization. As a specialist for cleaning mercury contaminated soil and waste by vacuum distillation econ also offers a process for mercury stabilization. For this, we don’t use a vacuum for once.
Mercury: fascinating metal and deadly poison
Mercury is a fascinating and at the same time a deadly element. It is the only metal which is liquid under normal conditions and found its way into alchemy, medicine and technology in ancient times. In modern times it played and still plays a role in the chlor-alkali electrolysis, in gold washing, dentistry and other applications.
The metal itself is not that dangerous. Even when swallowed, the human body can hardly absorb it and excretes it almost completely. More problematic, however, is mercury vapor, which is emitted from the metal even at room temperature. Absorbed by organisms, organic mercury compounds such as methylmercury are synthesized inside the body, which are poisonous and even capable of easily passing the vital blood-brain barrier.
Although the acute cases of mercury poisoning resulting in death can be counted on one hand, the creeping, chronic form is much more insidious. Because chemical bonds like methylmercury accumulate in organisms like fish they reach the human body via the plate. Symptoms range from headaches and limb pain via paralysis and psychoses to coma and death.
In view of such risks, the use of mercury has long been scrutinized more closely. In many areas, the problematic metal has already been replaced and removed piece by piece from the economic cycle. For example, during the remediation of old industrial sites using the environmentally friendly VacuDry® process the metal is extracted in its purest form. Now the challenge is to store it safely.
econ’s safe method of mercury stabilization
Mercuric sulfide is the only non-toxic mercury compound and therefore the ideal candidate for disposing the environmental toxin safely. One modification of this compound is known as cinnabar, a red powder that has been appreciated by many generations of painters. Cinnabar is nearly insolubly in water and stable over a very long time.
econ has developed an ultra-modern and efficient mercury stabilization unit which fits in a standard container. Completely enclosed and under nitrogen atmosphere, the pure mercury is converted into stable red cinnabar.
The fact that for once we don’t count on a vacuum in this process has physical and chemical reasons. The presence of even small amounts of oxygen during the reaction of mercury and sulfur can lead to deflagrations. If the reaction takes place in a vacuum, a tiny leakage is enough to cause air flowing from the outside into the reaction chamber. The consequences for personnel and the environment can be devastating.
However, the reaction in a hermetically sealed mixing system under a nitrogen atmosphere at ambient pressure is not only technically safe, it can also be controlled significantly easier. The inert gas keeps the oxygen away and the neutral pressure ensures that even in case of a complete failure of a seal or a faulty operation no explosive reaction can occur. In addition, the mixing vessel is designed in a sturdy and solid way. So even in the extremely unlikely event of a complete failure of econ’s redundant nitrogen supply the mixing vessel can absorb the explosion pressure. As a result, any risk for the operating personnel is avoided.
This stabilization method is easy to use and has already withstood the critical examination of external certifiers. econ provides the mercury stabilization not only for sale but also as an on-site service.