The scope of work for this project includes: 1) to update and establish the emission inventory of toxic air pollutants (dioxin and heavy metals); 2) to analyze the existing major pollutants and evaluate the reduction strategy; 3) to follow up the dioxin reduction achievements and prepare the action plan according to the reduction target; 4) to execute the emission investigation for heavy metals emitted from the small and medium waste incinerators; 5) to assist in drafting the dioxin emission standard; 6) to evaluate the feasibility of the 2007 dioxin emission standard for electric arc furnaces; 7) to review and amend the existing emission standard of heavy metals for waste incinerators and etc; 8) to collect and summarize the related information regarding dioxin emission data, available control technology and emission standards from foreign countries; 9) to assist in investigation of the dioxin- polluted-duck-eggs case at Chang-Hua County . The achievements of this project are described as below:
The scope of work for this project includes: 1) to update and establish the emission inventory of toxic air pollutants (dioxin and heavy metals); 2) to analyze the existing major pollutants and evaluate the reduction strategy; 3) to follow up the dioxin reduction achievements and prepare the action plan according to the reduction target; 4) to execute the emission investigation for heavy metals emitted from the small and medium waste incinerators; 5) to assist in drafting the dioxin emission standard; 6) to evaluate the feasibility of the 2007 dioxin emission standard for electric arc furnaces; 7) to review and amend the existing emission standard of heavy metals for waste incinerators and etc; 8) to collect and summarize the related information regarding dioxin emission data, available control technology and emission standards from foreign countries; 9) to assist in investigation of the dioxin- polluted-duck-eggs case at Chang-Hua County . The achievements of this project are described as below:
1. Estimation of the total dioxin emission in Taiwan area is 144.0 g I-TEQ in 2004, and the reduction target (175.0 g I-TEQ) is achieved. The total dioxin emission in 2004 is 38% less than the emission in 2003. The reduction is achieved due to the promulgation of the dioxin emission standard for small incinerator and electric arc furnace in 2004, which enhanced the pollution sources to take consequent reduction actions. The largest pollution source is Taiwan Union Steel, which counts for 47% of the total emission. The other major pollution sources are the sinters. The China Steel has fulfilled the consequent dioxin reduction actions in 2005. It is expected that the total dioxin emission will be even lower in the future.
2. A total of 24 small and medium incinerators have been tested for heavy metals emission (lead, cadmium, mercury and arsenic) in this project. Based on the testing results, it was found that the concentration in stack as well as the total emission quantity of most of the tested incinerators is low. Only one medical waste incinerator was detected high lead concentration. This shows that the heavy metal emission of the small and medium incinerators is well controlled.
3. Based on technology feasibility, risk assessment and foreign related legislation emission condition, the draft”Dioxin control and emission standard of the ashes thermal refining facility for steel industry” was prepared. Starting from Oct.12, 2005, the newly installed thermal refining facility should meet the emission standard of 0.4 ng-TEQ/Nm3. Starting from Oct.12, 2005, the existing thermal refining facility should be improved to meet the emission standard of 9 ng-TEQ/Nm3; and by September 1, 2006, the existing thermal refining facility should be improved to meet the emission standard of 1 ng-TEQ/Nm3.
4. In order to further reduce the impact of dioxin to the environment, the draft”Dioxin emission standard of the stationary sources”was prepared. Starting from January 2, 2006, the newly installed stationary sources should meet the emission standard of 0.5 ng-TEQ/Nm3. Starting from January 1, 2007, the existing stationary sources should be improved to meet the emission standard of 2.0 ng-TEQ/Nm3; and by January 1, 2008, the existing stationary sources should be improved to meet the emission standard of 1.0 ng-TEQ/Nm3. After that the dioxin emission from all the stationary sources are regulated by the standard.
5. The heavy metal emission standard of the waste incinerators was reviewed and the recommended revised standards are prepared in this project. The recommendations are: the newly installed incinerator with treatment capacity over or equal to 4 tons/hour, the lead emission standard is 0.2 mg / Nm3，the cadmium emission standard is 0.02 mg / Nm3 and the mercury emission standard is 0.05mg / Nm3. With treatment capacity less than 4 tons/hour, the lead emission standard is 0.5 mg / Nm3，the cadmium emission standard is 0.04 mg / Nm3 and the mercury emission standard is 0.05mg / Nm3. For the existing incinerator with treatment capacity over or equal to 4 tons/hour, the lead emission standard is 0.2 mg / Nm3，the cadmium emission standard is 0.04 mg / Nm3 and the mercury emission standard is 0.08mg / Nm3. With treatment capacity less than 4 tons/hour, the lead emission standard is 0.5 mg / Nm3，the cadmium emission standard is 0.04 mg / Nm3 and the mercury emission standard is 0.08mg / Nm3.
6. The existing dioxin emission standard for electric arc furnace is 5.0ng-TEQ/Nm3 which has been effective since January 1, 2004. Based on the audit data by city government and self-testing data by the owner of electric arc furnace, the dioxin emission standard has been achieved by all the tested pollution sources. The dioxin emission standard for electric arc furnace will be strengthened to 0.5ng-TEQ/Nm3 in January 1, 2007. Based on the existing audit data by city government, there will be 62% pollution sources which can conform to 0.5ng-TEQ/Nm3. According to self-testing data by the owner of electric arc furnace, there will be only one electric arc furnace that can not conform to 0.5ng-TEQ/Nm3.
7.During the project execution period, there was the dioxin- polluted-duck-eggs case occurred at Siansi Township and Shengang Township in Chang-Hua County. And the Taiwan Union Steel, one of the major pollution sources, is located near the duct farms. Supplementary tasks were added to this project, which includes: assist the EPA to prepare the emergency response actions; and execute the field dioxin investigation, which includes ambient air, plant, soil, feed, Little Egret and Black-crowned Night Heron etc., During the investigation period, the Taiwan Union Steel was ordered to shutdown. The investigation results show that the dioxin concentration in ambient air can meet the Japanese environmental quality standard 0.6 pg TEQWHO98/Nm3. Dioxin content in the plant is lower than the past as the result of Taiwan Union Steel has been shutdown and there was two typhoons passing by. The dioxin concentration in soil was below the Soil Dioxin Control Standard of 1000 ng TEQ/kg d.w. However, higher dioxin concentration in soil near the Yao, Ho-Mu duct farm was detected, and the site was later confirmed to be an illegal dumping site of slag and fly ashes. The results show that dioxin concentration is between 14.8 pg I-TEQ/g fat – 32.2 I-TEQ/g fat for Little Egret and Black-crowned Night Heron.
