Résumé : |
Methods of preventing the discharge of chromium from tanneries to the environment and their effectiveness and practicability are discussed, viz. Complete uptake and fixation at tanning, direct recycling of spent chrome liquors and precipitation of spent chrome liquors, including reconstitution of new chrome tanning material. However, the chromium cannot be prevented completely from dissipating into the environment. The naturally occuring chromium in soils and the uptake of chromium by plants is discussed. Effects of chromium of chromium on wastewater treatment plants, soils, plants and animals including man are considered, distinguishing between hexavalent and trivalent chromium. |