What are the main causes of air pollution in Baoji? Measures to eliminate (or reduce) pollution

(1) The static wind frequency in the surface layer of Baoji City is high. Due to the narrow terrain, the annual average wind speed is only 1.2m/s, which is not conducive to the diffusion of air pollutants, but the diffusion conditions in the middle and upper atmosphere are good. ② The diurnal variation of wind direction and wind speed in the atmospheric boundary layer in Baoji City is great, and the circulation characteristics of mountain-valley wind are obvious. The vertical variation of wind speed is great, and the wind direction shears by 200-500 meters, and the atmospheric diffusion capacity is higher than Xianyang and Xi 'an. ③ The mixed layer in Baoji City is relatively high, and the ventilation is about 30% larger than that in surrounding areas, which is beneficial to the outward diffusion of air pollutants above the middle layer. ④ The shear field of wind near the surface layer in Baoji City is located in the "Qianweihui" area, and the shear of wind direction and speed is large, and the flow field is obviously different. The static wind frequency to the east of Wolong Temple is 22%, which is about 30% less than that in the urban area, and the annual average wind speed is 2.2 m/s, which is higher than that in the urban area1m/s. ⑤ Baoji City has a large annual precipitation and a good surrounding ecological environment, which plays a significant role in rainwater scouring and ecological purification of air pollutants. ⑥ The special terrain and meteorological conditions in Baoji City make the average life and half-life of air pollutants shorter. ⑦ There is a static peak in Qinling Mountains, and when the northeast wind flows backwards in winter, it is easy to aggravate the air pollution in urban areas. This is mainly caused by the weather system. ⑧ The equivalent environmental capacity of SO2 and NO2 calculated by multivariate model only accounts for 53.8% and 65.7% of the ideal environmental capacity of SO2 and NO2 in Baoji, and the atmospheric environmental capacity is still relatively large. Pet-name ruby inhalable particulate matter PM 10 in urban area is mainly caused by ground dust, secondary particulate matter and external input due to the small proportion of emission sources (industry and traffic). Attending from the accounting results, the air pollution sources of Baoji No.2 Power Plant and Guozhen Industrial Zone have little influence on Baoji City. From the above conclusions, we can see that there is still a lot of room for Baoji's economic development, no matter from meteorological conditions or atmospheric environmental capacity. The main suggestions are as follows: ① Urban planning and industrial layout should fully consider the meteorological conditions of Baoji and follow the transport and diffusion law of atmospheric pollutants. ② The future industrial layout of Baoji City should expand from the east to the east of Heqian River. ③ The point source emission height of air pollution from newly-built enterprises should be increased, and its effective emission height should be above 75 meters, which is conducive to the rapid diffusion of air pollutants. ④ Baoyuan Thermal Power Company (formerly Baoji Power Plant) is the biggest point source of air pollution in urban areas. In 2004, the annual emission of PM 10 was 70.7 tons. 5830 tons less than in 2002. However, the annual emissions of SO2 and NO2 still account for 72% of the total urban point source emissions. Companies should speed up the treatment of sulfur dioxide and nitrogen dioxide. ⑤ The air quality in the northern platform of the urban area (Lingyuan and Panlong platforms) is good, which is conducive to the diffusion of air pollutants and suitable for the construction of residential areas. ⑥ In the utilization of surplus atmospheric environmental capacity, more new enterprises with less resource consumption, high technology content and less environmental pollution will be developed, and heavily polluting enterprises will be prohibited from entering urban areas. ⑦ The environmental management department should speed up the implementation of the reduction plan, rationally utilize the existing atmospheric environmental capacity resources, and promote the sustainable development of Baoji City.