The invention relates to the use of maghemite nanoparticles at pH less than 5 to remove sulphate, manganese, copper, nickel, cobalt and zinc metal ions from acid mine drainage (AMD). In conventional AMD treatment, these pollutants are only removed at higher pH, and that requires costly alkaline
The technology relates to a system which harvests thermal energy from various sources (e.g., sunlight, cars, power plants, factories and other industries) and converts it into electricity. In this system, heat energy is harvested and then stored in a storage tank, using water as energy storage