The invention solves the problems of inefficiency which usually shows the conventional passive treatment systems. The reactive fills developed for the removal of inorganic contaminants historically have focused on removing low concentrations of these (typical features of coal mining), however when these fillers are faced to high concentrations of metals (sulfur mining, uranium, industrial water waste…) quickly clogging and loss of reactivity occurs. The present invention allows the removal of metals without clogging and/or loss of reactivity. This is achieved by the use of a coarse inert material with high surface mixed with a fine-grained reactive material, so that the surface of the inert material is breaded with reactive material. Coarse fragments of inert material act as a frame, providing large pores that reduces clogging by precipitates. The small particle size of the reactive material provides a large surface area that increases its reactivity.
Description of the technology
The present invention relates to a process for purifying contaminated waters by metals, such as acid mine drainage, and to the installation for implementing the procedure. Consists of a series of processes that cause oxidation, neutralization and precipitation of the metal components which contaminate the water, so that water is free of metals finally. The invention allows the removal of metals sustainably, without continuous addition of chemical reagents and without use of energy.
The most relevant feature of this technology is the reactive material developed which is at the same time permeable and reactive, and also has the property that when it starts to lose its primary porosity by void filler develop a secondary porosity by dissolution of the reactive material.
Main advantages of its use
- The benefits of this technology are based in its passive nature: once the system is built need minor maintenance or monitoring. Polluted water flows throughout the system by gravity force, so no need to use external energy. The reactive mixture used for oxidation, neutralization and precipitation the pollutants is made by low cost and conventional materials. The first environmental advantage is that the procedure and the system is a green technology, because the aim of this procedure and system is the metal removal from polluted waters, and the environmental impact derived for its built is minimum compared with the environmental benefits.
- Industrial sectors derived from mining and mineral processing. The applications are associated with the passive treatment of metal polluted waters, which are always present in working and abandoned mines, and in metallurgical or mineral processing industrial facilities. The customer profile are the minning and mineral processing companies, and also the environmental authorities when the polluted waters come from old abandoned mines or industrial facilities.