二氧化硫在烤烟密集烤房群周围的空间分布

为实现 “节能减排、省工降耗”,同时为建设环境友好型现代烟草农业提供理论依据,以烤烟密集烤房群为监测对象,利用ecom-J2KN烟气分析仪和大气采样器对烤烟烘烤过程中密集烤房烟囱气体成分和烤房群周围空间环境SO₂浓度变化进行研究.结果表明: 烤烟烘烤过程烟囱烟气中CO₂和SO₂均在38 ℃稳温时最大,氮氧化物在42 ℃稳温时最大;SO₂排放浓度范围为1327.60～2218.40 mg·m^-3;通过添加4.0%的固硫剂,平均SO₂排放可减少49.7%.对烤房群下风向SO₂扩散的测算表明,SO₂地面浓度最大值出现在变黄期;水平方向43～80 m范围内,SO₂质量浓度超出0.5 mg·m^-3,其中50 m处的空气中SO₂浓度值最高,为0.57 mg·m^-3;在距离烤房群50 m的垂直方向上,距离地面0.9～1.8 m高处的SO₂质量浓度均超出0.5 mg·m^-3,其中1.6 m高处的SO₂浓度达到最高,为0.65 mg·m^-3;通过添加固硫剂,可使SO₂质量浓度平均降低0.43 mg·m^-3.密集烤房群下风向水平距离120 m范围内属于大气环境防护距离.

Spatial distribution of sulfur dioxide around a tobacco bulk-curing workshop cluster.

In order to manifest lower energy consumption and less labor employment, and provide the theoretical basis for constructing environmentally friendly modern tobacco agriculture, this paper analyzed gas composition of the chimney from a bulk-curing barn and the dispersion of sulfur dioxide (SO₂) around the workshop cluster using ecom-J2KN flue gas analyzer and air sampler. During curing, the concentrations of carbon dioxide (CO₂) and SO₂ in the chimney were both highest at 38 ℃, while the concentration of nitrogen oxides (NO_x) was highest at 42 ℃. The emission concentration of SO₂ from the chimney was 1327.60-2218.40 mg·m^-3. Average SO₂ emission would decrease by 49.7% through adding 4.0% of a sulfur-fixed agent. The highest concentrations of SO₂ in the surface soil appeared at the yellowing stage. SO₂ concentration in horizontal direction loca lized at 43-80 m exceeded 0.5 mg·m^-3. The highest concentration of SO₂ (0.57 mg·m^-3) was observed at 50 m. At 50 m in the downstream wind direction of the workshop cluster, SO₂ concentration in vertical direction localized at 0.9-1.8 m exceeded 0.5 mg·m^-3, and the highest concentration of SO₂ in vertical direction was 0.65 mg·m^-3 at 1.6 m. During curing, the average concentration of SO₂ was decreased by 0.43 mg·m^-3 by using the sulfur-fixed agent. The polluted boundary was localized at 120 m in the downstream wind direction of the workshop cluster.