The scope of work for this project includes analyzing air quality trend and develop air quality improvement goals of air quality zone, promoting the control strategy and pollution reduction of major development projects or main pollutant source hotspot, promoting the air pollution control and emission standards of volatile organic compounds(VOCs), tracing the air pollution reduction and improvement effects of the No.6 Naphtha Cracking Plant, reviewing the amendments to the stationary source emission standards, improving the reduction effect of fine suspended particles(PM2.5). The critical results are abstracted as followed:
1.Analyzing air quality trend and develop air quality improvement goals of air quality area.
EPA has announced the modified air quality control region for each class of special municipality, county and city on 2012/6/14, and the amendment will be in effect on 2013/1/1. In which, Nantou country PM2.5 deteriorated to Class 3 control region. It may relate to river bank fugitive dust, river channel dredging work, and transportation of earth and gravel caused by Typhoon Morakot. The improvement of ozone control region may relate to improvement of stationary source and mobile sources or climate change.
The poor air quality rate of Central Taiwan and Yun-Chia-Nan Air Quality Zone (including Nantou County) had improved significantly in 2012, which is the best condition for the past decade. Emission factor analysis shows that in 2011 the SOx and NOx emissions reduction is 29.4% and 23.2% comparing to 2001. The main strategy of VOCs control in the early stage is to identify major emissions sources. The VOCs reduction will be done in the future. Between 1987 and 2009, mobile sources showed 5% reduction in PM10 emissions, 95% reduction in SOx emissions, 22% reduction in NOx emissions, 69% reduction in NMHC emissions, 68% reduction in CO emissions, and 98% reduction in Pb emissions. It shows that the implementation of control measures have been effective. However, the amount of vehicles has grown by 30% between 1999 and 2009; the emissions reduction of mobile sources has reached a bottleneck. The meteorological factor analysis shows that the monthly raining days in 2012 were significantly higher than past few years. It contributed to the removal of primary pollutants and reduced the generation rate of secondary pollutants.
According to the analysis of the air quality impact from the No.6 Naphtha Cracking Plant, the concentration of ethylene and propylene at Taisi monitoring site is higher than other sites. The SOx abnormal days reached 80 days per year since the operation of the plant. However, it has started to improve in 2008, and decreased to 12 days per year in 2011.
Maximum concentrations of ethylene, propylene and benzene detected at the Taisi monitoring site occurred in a specific wind direction(north-northwest). It may be caused by the constant emissions from flares in the north-northwest wind direction.
2. Promoting the control strategy and pollution reduction of major development projects or main pollutant source hotspot.
The emission reduction strategies in air quality zones were proposed by local governments and coordinated by the central government.
Issues of controlling mobile sources in designated “Clean Air Zones” include dispute of sanctions in Alishan, and joint investigation of diesel cars in 7 counties and cities to prevent cars from escaping inspections by taking detours.
Fugitive source air pollution issues include tracking the improvement of fugitive dust from construction of West Coast Expressway(Route 61), promoting the cooperation and consultation mechanisms of ChoShui River fugitive dust control, and feasibility of reducing the straw open burning, straw reuse platform and incineration.
Stationary sources issues including major development projects (ex. Taichung Harbor) will be implement in the next phase according to the air pollution control experience of the No.6 Naphtha Cracking Plant. Small and medium-sized pollution sources issues include lump coal boiler control and the study of change of fuel consumption.
For the change of pollution source fuel consumption trends, such as oil changed to lump coal, oil changed to NG or LPG, lump coal changed to biomass etc., we proposed the improvements including strengthen the particle emission standards, proposed the sulfur content detection method of lump coal, proposed the specific heating value emission standard, and analyzed the feasibility of the oil fuel boiler changed to NG, LPG or biomass fuel.
3. Promoting the air pollution control and emission standards of volatile organic compounds (VOCs) and tracing the effect of air pollution reduction of the No.6 Naphtha Cracking Plant.
For the promoting of VOCs air pollution control and emission standards, we helped developing four VOCs standards reporting forms and assisted Environmental Analysis Laboratory in the completion of four test methods. There are still two test methods amendments in progress.
For the tracking of No.6 Naphtha Cracking Plant air pollution reduction results, the audit found out that the heating value of exhaust gas was too low in 2011. It had been solved by adding fuel gas. The total sulfur emissions of the Naphtha Cracking Plant will be reduced after the completion of high-temperature oxidation equipment in 2011. The leakage problem of equipment components had been solved by using the online repair technique. The chance of leak concentration greater than 10,000ppm was decreased from 0.13% in 1997 to 0.04% in 2011. It has gotten preliminary results. After the VOCs standards take effect, the VOCs, SOx and CO2 emissions reduction from flare and other equipments were 986, 916 and 1,385,572 tons per year, respectively.
For confirming air pollutant emissions from the No.6 Naphtha Cracking Plant, in the 219th EIA meeting(2012/7/25), EIA adopted that emission estimating item should include flare(including abnormal emission), painting ,cooling tower, tank washing and yearly repair. The confirming method was into the final draft. Our project helped EPA and Yunlin County EPD jointly to resolve the No.6 Naphtha Cracking Plant air pollution emission dispute.
For the implement difficulties of VOCs standards, the industry suggested to cut down the investigating item of local competent authorities. According to the suggestion, our project also collected the international control regulations and methods providing references to local competent authorities.
4. Review of the amendments to the stationary source emission standards, and improve the reduction effect of fine suspended particles(PM2.5)
Our project proposed eleven revision drafts for the emission standards announced in 80s. If these standards were coming into effect, the estimating pollution reductions of particle would be 3,823 tons per year, sulfur oxides reduction would be 12,733 tons per year, and nitrogen oxides reduction would be 37,089 tons per year. Among them, the revision draft for power generation facilities has the highest emission reduction. The coal-fired cogeneration boilers in our country need to invest 4.62 billion NT dollars in adding SCR to comply with NOx emission limits.
Considering emissions, energy conservation and carbon reduction and etc., it is recommended that five drafts should be implemented first. Steel Industry Sintering Plant Dioxin Control and Emission Standards had been announced on 2012/6/14. Notification for amendment of Stationary Pollution Source and steelmaking industry electric arc furnace emission standards were also announced. Power generation facilities and glass industry emission standards had been discussed with the industry sufficiently.