Demercurization of mercury

Despite all precautions when working with mercury, accidents can occur in laboratory and production conditions, accompanied by mercury contamination of premises, equipment and clothing.

Demercurization of premises includes mechanical cleaning of visible amounts of mercury and chemical treatment of contaminated sites, followed by careful removal of mercury reaction products with chemical reagents.

For mechanical removal of spilled mercury, a glass trap with a rubber pear is used. Small amounts of spilled mercury can be collected with amalgamated strips or brushes made of tinplate, copper or brass wire and other amalgamating metals, as well as from metallized coal wolves.

To collect the droplets of mercury, a sticking plaster is also used, which is applied to a surface contaminated with mercury. The droplets of mercury adhering to the adhesive plaster are separated from it by washing with acetone or other organic solvents.

For demercurization of premises in production conditions, a mobile TD unit can be used that has a chamber that can be heated to 2000 ° C.
The mechanical treatment of contaminated surfaces from mercury is not enough, since mercury droplets may be retained if there are cracks or crevices in the surface.
For chemical cleaning of surfaces contaminated with mercury, solutions of potassium permanganate are often used. It is recommended to use a solution, in 1L. Which contains 1r. Potassium permanganate and 5 ml. Hydrochloric acid (density 1.19 g / cm2). Also, solutions of sodium sulfide and iron (III) chloride, a composition containing 15-20% ethylenediaminetetraacetic acid and
80-85% of thiosulphate (25 g of this mixture is dissolved in 1 liter of water), etc.

It is known that fabrics, especially those painted in dark colors, absorb mercury vapor well. However, in industrial conditions or when working with mercury in laboratories, the main source of garment contamination is not the sorption of its vapors, but the ingress of small droplets and splashes onto clothing due to careless handling of mercury. Mercury, which got on clothes and adsorbed it, is an additional source of poisoning not only for the one who wears these clothes, but also for those around. In the workplace and in the laboratory, when operating with large amounts of mercury, you should use outerwear, linens and shoes designed only for working with mercury. In accordance with the rules for washing clothes when working with mercury (not at home), contaminated clothing is freed from dust, loaded into the drum of the washing machine and rinsed with cold water for 30 minutes.

The washed overalls are poured with a soap-soda solution and washed for 30 minutes at 70-800 C. The washed clothes are washed in a drum first with hot and then with cold water and treated with a 1-2% solution of hydrochloric acid for 30 minutes. After that, repeat washing is performed. With this washing, the fabric is released from mercury by 96-99%. Individual protection and personal prevention measures.

When working with mercury and mercury devices, accidents can occur associated with the explosion of mercury equipment in which metallic mercury or highly toxic mercury compounds can be under high pressure and at temperatures much higher than their boiling point. In this case, the workplace is contaminated with tiny drops of mercury or the dust of its toxic compounds. In this connection, for workplaces for individual protection it is necessary to have oxygen insulating devices or industrial anti-mercury gas masks of “G” brand (yellow-black box), which in case of accident reliably protect workers from poisoning.

When working with mercury it is very important to carry out personal preventive measures, because otherwise no sanitary measures will prevent poisoning. Work with mercury is necessary in starched overalls, made of dense white fabric, tightly tied behind a ball gown without pockets, a white kerchief or a white cap.

Do not work in felted or soft cloth shoes. It is recommended to protect leather or rubber footwear with polyvinylchloride covers; Use this clothing only when working with mercury, and then they should be left in the dressing room.

At the end of work, and before eating, hands and face should be washed with warm water and soap, and after work take a shower and often visit the bath. When washing with hot water, the skin is cleansed, which helps to remove mercury from the body, since it, in particular, is secreted by sweat glands.
You can not smoke, eat and drink milk in the workplace, this should be done in specially designated rooms. During breaks in work should be in the open air, and, where possible, – engage in production gymnastics; Systematic training in physical culture and sports enhance the body’s resistance to harmful effects of mercury, strengthen the nervous system.

Along with preventive measures of a general nature, medicinal methods for preventing mercury poisoning are known, using various pharmacological preparations that increase the overall resistance of the organism to poisoning. In particular, thiol compounds have recently begun to be used as individual prevention agents, among which 2,3-dimercaptopropanesulfonate, the so-called unitiol, has the greatest antidote activity.

This drug is low in toxicity, improves metabolism and increases the overall resistance of the body. The drug, introduced before the entry of mercury vapor into the body, subsequently binds mercury and prevents poisoning, and when administered under conditions of chronic intoxication contributes to a faster and more complete removal of mercury from the body, especially during the initial period of administration.