| 英文摘要 |
In 2010 every cities and counties in Central and Yun-Chia-Nan Air Quality Zones were rated as Class 2 for ozone and particulate matters. In 2014, only the Kaohsiung and Pingtung Air quality zone were rated as Class 3 for ozone quality; Kaohsiung, Pingtung, , Yunlin, Chiayi, and Tainan were rated as Class 3 for particulate matters, which has improved significantly since 2000. However, for all cities and counties, the annual average concentration of PM2.5 was 23.5μg/m3, with every cities and counties in western Taiwan surpassing the national standard of 15μg/m3.
This project has three main tasks: 1. Emission control in emission hot spots. 2. Reduce emission in air quality zones. 2. Revise emission standards for major stationary sources. Each task will be explained further below.
I. Emission control in emission hot spots
The air quality monitoring results around the Sixth Naphtha Cracking Plant is gradually improving over the years. The propylene and benzene concentration was reduced by 60% and 35% respectively since 2007, due to the implementation of the new VOCs regulations and reduction of flaring.
From 2000 to 2007, the non-attainment days of ozone in Yun-Chia-Nan Air Quality Zones increased along with the increase of ethylene production. After 2007, with the implementation of various control strategies, the non-attainment days had decreased from 16 days in 2007 to 1 day on 2015 regardless of further increase in ethylene production. The SO2 concentration detected in Taixi monitoring station also displayed decreasing patterns since 2007.
Even though, the regulations allow the usage of flares during annual maintenance, the annual maintenance of the FPC Company OL3 factory in 2014 resulted several air pollution incidents. On Aug. 15th and 16th, the propylene concentration reached 56.3ppbC in Chung-Ming monitoring station. On Aug. 21st, complaints was filled by the nearby elementary school. On Sept. 27th and 30th, the O3 exceeded the standard. The EPA had requested the company to improve its flare tower operation procedures during the maintenance period.
The VOCs regulations demands a reduction project from those who uses flare towers for more than 30 days. Reduction measures were also taken regarding to components and storage tanks.
As for the management of petrochemical hot spot in Kaohsiung and Pingtung, the number of ozone non-attainment day has decreased from 23 days in 2007 to 10 days in 2014. Monitoring and modeling data indicates that the USI facory and the CPC’s Third Naphtha Cracking are the major sources. After implementing flue gas recovery system in flares, only 4 non-attainment days for ozone was observed as of December 2015; below the 8 day threshold for Class 2 air quality zone.
To control the emission in Taichung Port Area, regulations were strengthened to reduce emissions from Taichung Power Plant, Dragon Steel Company, and the logistic companies. To reduce mobile source emissions, filters were applied to trucks and ships along with reducing speed limit while entering the port area. Measure were also taken to reduce fugitive particulate emissions.
The PM2.5 concentration in Shalu are around 4 in 2010 and 2013. To further reduce emission, cogeneration and distribution of heat and energy in Taichung Port Area is recommended. Further reduction on mobile sources is also recommended.
II. Emission reduction in air quality zones
The Central Air Quality Zone has been upgraded to Class 2 for PM10 improvements due to regulations in storage fields, construction sites, and river dredging projects. Same strategies will be implemented in Yun-Chia-Nan Air Qaulity Zone to improve PM10 concentration there.
The precursors of PM2.5 have seen reduction over the last decade(2005 to 2014). SO2 concentration was reduced by 23% and 24% in Central and Yun-Chia-Nan Air Quality Zones respectively. NO2 was reduced by 20% and 17%; NMHC was reduced by 25% and 21%. Ammonia concentration in Lunbei was the highest among the 5 stations in Taiwan; it hasn’t shown any significant reduction over the years. NH3 mainly comes from sewers and livestock. Construction of sewer collection system and anaerobic digesters is advised.
III. The Revision of Stationary Sources Emission Standards
This year the emission standards for cement factories is being revised. Other than strengthening the traditional PSN standards, mercury and fluoride standards were also implemented.
After the implementation of the new VOCs standards, the number of non-attainment days for ozone has significantly decreased. However, its effect on PM2.5 concentration is still unclear; further investigation is still required. Further investigation is also required to understand the effects of the newly implemented emission standards for steel refineries, glass manufactures, electricity industries, and stationary sources on the PM2.5 concentrations.
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