Disposal of Obsolete Pesticides Including DDT in a Chinese Cement Plant as Blueprint for Future Environmentally Sound Co-Processing of Hazardous Waste Including POPS in the Cement Industry

In September 2009, 350 tons of Obsolete Pesticides (OP) including 160 tons of DDT (dichlorodiphenyltrichloroethane, a Persistent Organic Pollutant, POP) has been successfully disposed as a business case in Huaxin Jinmao Cement Company at Suzhou, China. Disposal of the Ops was carried out in a New Suspension Pre-calciner (NSP) kiln with clinker capacity of 3’200 tons per day. Before disposal campaign, a comprehensive trial burn scheme designed beforehand was conducted to find out the optimized operation parameters such as feeding rates and to get insight of Destruction Removal Efficiency (DRE) of DDT and as well as the emission level of Dioxins/Furans. In the trial, DDT feeding rates ranged from 150 kg/h, 500 kg/h, 1’000 kg/h and up to 2’000 kg/h at maximum. The results revealed that DRE of 99.99999% and emission of Dioxins/Furans well below 0.1 ng TEQ/Nm3 were found out when 2 tons of DDT preparations of 30% chlorine content in the highest among the series are fed to the kiln.