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Clinoptilolite- a natural zeolite has been investigated for the removal of heavy metals from the wastewaters. A pyrex-glass column of 30 mm diameter and 600 mm height was used. The column was filled with the conditioned clinoptilolite of 0.5-1 mm. In the first stage of the research, synthetic wastewater containing single cation 0.02 N and 0.04 N Cu and 0.02 N Fe and Zn solutions were passed through the column. Two liter of 0.02 N Cu and 750 ml of the 0.04 N Cu solution was treated with 100 percent removal efficiency. Clinoptilolite column was regenerated for the reuse when the removal efficiency decreased. The cation exchange capacities were calculated as 1.0663 and 1.5342 meq/g clinoptilolite for 0.02 N and 0.04 N Cu solutions, respectively. In the second stage of this research, the same procedure was repeated with the actual wastewater samples of the equalization and the neutralization tanks of the Telka-Rabak Electrolytic Copper Industry. A volume of 1811 ml of the wastewater of the equalization tank and 180 ml of the neutralization tank wastewater, which had high concentrations of Ni, Zn, Cu and Fe, was treated with 100 percent efficiency. The cation exchange capacities of clinoptilolite for the wastewater of the equalization and the neutralization tanks for Cu were 0.4483 and 0.4274, respectively. It was observed that only one third of the single copper ion solutions were obtained with the actual wastewater having competing ions such as Zn, Fe and Ni. The experimental results also indicate that the clinoptilolite is an effective cation exchanger for the removal of the metals from the wastewater and the removal efficiency is higher when there is not ant competing ions.

The open dump of Ümraniye-Hekimbaşi was the main solid disposal site of the Asiatic side of Istanbul. At this site, which was in operation since 1976, 1500-2000 tonnes of solid wastes were disposed of daily. No waste compaction was undertaken during placement. The slope formed by the solid wastes was very steep (3 vertical to 1 horizontal), and recently demolition wastes were disposed of on top of these wastes. On 28 April 1993, an "explosion" took place, followed by the displacement of a large mass of solid wastes which engulfed 11 houses causing the death of 39 people. This paper investigates the possible reasons for this accident and concludes that it was caused by the initial sliding of the solid wastes, which were not deposited in a stable way, followed by an explosion of the methane generated and retained in the landfill. © 1995 ISWA

Efficient health-care waste management is crucial for the prevention of the exposure of health-care workers, patients, and the community to infections, toxic wastes and injuries as well as the protection of the environment (Safe Management of Wastes from Health-care Activities. World Health Organization, Geneva). The amount of health-care waste produced in the Istanbul Metropolitan City in Turkey is 30 ton day(-1) in total. The method used for the final disposal of most of the health-care waste of Istanbul is incineration. However, a great portion of the infectious waste is disposed of with the domestic waste into the sanitary landfill because of improper segregation practices applied in the health-care institutions. Therefore the alternatives for the treatment and disposal of health-care waste were evaluated. The technical information related to the available treatment technologies including incineration, microwave irradiation, mobile or stationary sterilization, etc. were also investigated. The capital investment cost, transportation/operational costs for each alternative method and the different locations for installation were compared. When the data collected were evaluated, it was found that separate handling and disposal of health-care waste generated on the European and the Asian sides of the city was the most economic and practicable solution. As a result, it was concluded that the capacity of the Kemerburgaz-Odayeri incineration plant is enough to incinerate the health-care waste generated on the European side of Istanbul, the construction of a new incineration plant or a stationary sterilization unit for the disposal of health-care waste generated on the Asian side was the most effective alternative.