小风条件下工业园区无组织VOCs溯源方法

为在小风条件下对工业园区周边监测点的无组织VOCs来源进行溯源解析，建立了以烟团积分扩散模型为基础的工业园区无组织VOCs排放溯源模型。通过小风条件下烟团积分扩散模型，计算有组织VOCs排放源对园区下风向监测点的VOCs质量浓度贡献；并结合上风向监测点背景值（VOCs）及下风向监测点质量浓度值（TVOCs），计算无组织排放源对下风向监测点的质量浓度贡献。根据无组织VOCs排放面源的位置坐标，利用小风条件下烟团积分扩散模型，建立无组织排放源与下风向监测点之间的响应模型；再利用最小二乘法反演出各无组织面源的VOCs排放强度，最后得到VOCs从各无组织排放源到下风向监测点的质量浓度和各监测点的浓度贡献比。在此基础上，推断出各监测点的无组织VOCs来源。溯源结果说明：在监测点S₁，无组织排放源D₁的污染物贡献率为25.71%，D₂的污染物贡献率为5.24%，D₃的污染物贡献率为3.81%；在监测点S₄，无组织排放源D₁的污染物贡献率为14.59%，D₂的污染物贡献率为36.31%，D₃的污染物贡献率为4.83%；在监测点S₁₂，无组织排放源D₁的污染物贡献率为20.17%， D₂的污染物贡献率为0.33%，D₃的污染物贡献率为0.39%。统计结果表明，工业园区无组织VOCs的理论计算值与实际值的误差平方和 R为0.001 5。本研究结果可为小风条件下工业园区无组织VOCs排放溯源解析提供参考。

Research on traceability method of unorganized VOCs emission in industrial park under low wind condition

In order to trace and analyze the source of unorganized VOCs from monitoring points around the industrial park under the condition of low wind and quickly locate the pollution source, a traceability model of unorganized VOCs emissions from the industrial park was established based on the smoke integral diffusion model backward method. Firstly, the concentration contribution value of organized VOCs emission source to downwind monitoring point in industrial park was calculated by smoke cluster integral diffusion model under low wind condition. The contribution value of unorganized VOCs emission source to downwind monitoring point was calculated according to the TVOCs value of downwind monitoring point and VOCs environmental background value of upwind monitoring point. Then combined with the location coordinates of the disorganized VOCs emission point source, the relationship between disorganized VOCs emission source and downwind monitoring point was established by using the smoke cluster integral diffusion model under low wind condition, and the emission source strength of each disorganized VOCs emission point source was calculated by using the least square method. Finally, the concentration of each unorganized VOCs emission source to the downwind monitoring point and the concentration contribution ratio to the monitoring point are calculated. The results can clearly infer the source of unorganized VOCs at each monitoring point. In this case, at the monitoring site S1, 25.71% of the pollutants come from the disorganized VOCs emission source D1, 5.24% from D2, and 3.81% from D3. In S4, 14.59% were derived from D1, 36.31% from D2, and 4.83% from D3. In monitoring site S12, 20.17% came from D1, 0.33% from D2 and 0.39% from D3. The sum of squares of error R between the theoretical calculated value and the actual value of unorganized VOCs in industrial park is 0.0015. This study provides a new idea for the traceability analysis of unorganized VOCs emissions from industrial parks.