摘要 |
The invention relates to a method of separating and neutralizing heavy metals such as mercury and cadmium and lead of dangerous waste. When a classification of the source has been made, the heavy metals dangerous to the environment are to be destructed separately. At the same time as Hg and Cd are present in the gas phase in a heat treatment oven and lead is in the liquid phase, elementary Se is boiled off. By a following chemical reaction the heavy metals are neutralized when they are transferred into their metal selenides. A further chemical reaction will take place in the oven when a glass melt is formed. Then, the glass melt dissolves the metals which are assimilated by the glass; a vitrification has taken place. In the process the resources of the waste are utilized in such a manner that the composition of the waste will affect the final result, i.e. a glass billet is formed which neutralizes eternally fluorescent lamps, batteries etc. in a safe and simple manner. |