EFFECTS OF COPPER CONTAMINATION ON DIOXIN EMISSIONS FROM CFC INCINERATION

A test program was developed and implemented for investigating the eff ects of copper contamination on dioxin emissions from incinerating chl orofluorocarbons (CFCs). Experiments were performed using a turbulent flame reactor (TFR) with a capacity of 21 kW to investigate the effect of copper contamination in the combustor refractory on dioxin emissio ns. Distillate fuel oil doped with copper naphthenate was fired, follo wed by a copper nitrate solution which was injected into the TFR fired by natural gas, with 1 g/hr copper injection rate for a total of 20 h ours prior to the incineration of the unused, pure CFC-12 (8.7 vol% CF C-12, 92.3 vol% propane fuel). High dioxin emissions (454 ng/dscm tota l polychlorinated dibenzo-p-dioxins and dibenzofurans) were observed. Subsequent firing of the TFR with the propane fuel for 54 hours reduce d the dioxin emissions to about 386 ng/dscm during the following CFC-1 2 incineration test. The test results suggest that high dioxin emissio ns could be caused by a strong promotional effect when highly chlorina ted wastes, such as CFCs, are incinerated in a facility on which the r efractory is contaminated with trace levels of copper from the previou s treatment of a cooper-containing waste. Incineration tests were also performed on a recovered CFC-11,refrigerant which contains 5 vol% res idual oil (with 4 ppm copper contaminant in the oil). The test results show that the level of copper contaminant contained in the recovered CFC-11 is insufficient to cause dioxin emissions. The high levels (>99 .999%) of destruction efficiency and the low levels of products of inc omplete combustion (PICs) emissions from the incineration of the recov ered CFC-11 are found to be very similar to those from the incineratio n of unused, pure CFCs.