USING SOLID WASTE OF SOME FOOD FACTORIES TO REMOVE HEAVY METALS FROM THE INDUSTRIAL WASTE WATER

The solid waste of some food factories such as dates syrups, tomato paste were used to remove heavy metals like Pb, Cr, Cd, and Fe from their standard solution and samples of waste water from leather factories. Results showed that the percentage of removal efficiency of heavy metals like Fe, Cu, Cr, Pb, Zn and Cd in their standard solution when dates stone powder was used were 68.8%, 79.3%, 88.9%, 90%, 91.58%, and 92.2%, respectively. On the other hand, the percentage of removal efficiency of heavy metals from waste water of leather factory, when dates stone powder was used were 99.9%, 54.1%, 52.4% and 62.5% for Cr, Pb, Fe, and Zn, respectively. Both date skin waste powder and tomatoes seed waste powder achieved the following removal efficiency percentages when they used on waste water from leather factory were 99.9%, 51.7%, 40.9% and 40% for Cr, Pb, Fe, and Zn when dates skin waste powder was used and were 98%, 48.8%, 55.9% and 41% when tomato skin powder was used. Both pH and temperature have a significant effects on the percentage of removal efficiency of heavy metals.