工业园区边界污染气体定量分析及来源研究

Quantitative Analysis and Source of Trans-Boundary Gas Pollution in Industrial Park

工业园区中边界污染气体的浓度不仅受工业园区无组织污染源的排放影响,也受园区道路机动车尾气的扩散影响。利用AG-FTIR-DA3000型开放光程傅里叶变换红外光谱(Open-FTIR)测量系统,对厂区边界污染气体进行实时在线测量,确定污染气体厂界实测浓度。同时,针对机动车尾气扩散影响厂区边界污染气体浓度的问题,通过AG-FTIR-DX4000型便携式傅里叶变换红外光谱(FTIR)测量系统,确定不同排放标准下机动车尾气污染源浓度。利用便携式FTIR测量结果、风速风向、大气稳定度、车流量等变量因素建立参考坐标,给出了高斯扩散的数理模型。并结合Open-FTIR,对Open-FTIR的测量路径进行积分计算并构建点线源扩散模型,从而建立各种排放标准的烟团线源扩散表。将Open-FTIR实测浓度与构建的点线源扩散模型模拟浓度相结合,分析工业园区边界污染气体的来源。结果表明:厂区边界污染气体主要包括一氧化碳、甲烷、乙烯、乙醛、丙烯、甲醇、丙醛、异丁烯、甲醛、二氧化硫,其中一氧化碳、甲烷、乙烯浓度受机动车尾气的扩散影响。早晚高峰期时,机动车尾气的扩散对边界污染气体浓度影响较大;非高峰期,在1:00时与4:00—6:00时浓度骤升,出现高浓度点,不符合机动车尾气模型排放规则,主要受园区排放影响。其最高浓度与集中浓度分别为:5.50与4.00 mg·m^(-3);1.85与1.60 mg·m^(-3);78.00与40.00μg·m^(-3)。对比扩散表,符合尾气扩散浓度分布结果。其他测量结果组分的最高值和平均值依次为:1.65与1.40 mg·m^(-3);2.60与1.27 mg·m^(-3);43.53与11.40 mg·m^(-3);310.23与839.05μg·m^(-3);76.32与38.96μg·m^(-3);47.70与25.20μg·m^(-3);1.33与1.16 mg·m^(-3)。该研究不仅实现了工业园区边界多组分污染气体的实时在线测量,同时结合外场环境及便携式FTIR测量结果实现了边界污染气体浓度的混合测定。为今后对工业园区边界污染气体的来源判断提供了一种分析思路。

The concentration of pollution gas at the boundary of industrial parks is not only affected by the discharge of unorganized pollution sources in industrial parks but also by the diffusion of vehicle exhaust gas on roads in industrial parks.The ag-FTIR-DA3000 open-FTIR system was used to measure the polluted gas at the plant boundary in real-time and determine the measured concentration of the polluted gas at the plant boundary.At the same time,aiming at the problem that the diffusion of motor vehicle exhaust affects the concentration of polluting gas at the factory boundary,the concentration of motor vehicle exhaust pollution source with different emission standards is determined by ag-FTIR-DX4000 portable Fourier to transform infrared(FTIR)measurement system.A mathematical model of Gaussian diffusion was established based on the results of portable FTIR measurement,wind speed and direction,atmospheric stability,traffic flow and other variable factors.Combined with the open-FTIR measurement method,the integral calculation of the Open-FTIR measurement path was carried out,and the point-line source diffusion model was constructed to establish the smoke cluster line-source diffusion table of various emission standards.The concentration measured by Open-FTIR was combined with the concentration simulated by the point-line diffusion model to analyze the concentration source at the industrial park’s boundary.The comprehensive analysis results show that other polluting gases at the factory boundary mainly include carbon monoxide,methane,ethylene,acetaldehyde,propylene,methanol,propyl aldehyde,isobutene,formaldehyde and sulfur dioxide.The concentrations of carbon monoxide,methane and ethylene at the boundary are greatly affected by motor vehicle exhaust,and the concentrations of polluting gas at the boundary are greatly affected by motor vehicle exhaust diffusion at the peak time in the morning and evening.Off-peak,the concentration rises sharply at 1:00 and 4:00-6:00,and the high concentration point appears,which is not in line with the motor vehicle exhaust model emission rules,mainly affected by the park emissions.The maximum and average concentrations were 5.50 and 4.00 mg·m^(-3),respectively.1.85 and 1.60 mg·m^(-3);78.00 and 40.00μg·m^(-3).The diffusion concentration distribution results of tail gas are consistent.The highest and average values of other components were 1.65 and 1.40 mg·m^(-3) respectively.2.60 and 1.27 mg·m^(-3);43.53 and 11.40 mg·m^(-3);310.23 and 839.05μg·m^(-3);76.32 and 38.96μg·m^(-3);47.70 and 25.20μg·m^(-3);1.33 and 1.16 mg·m^(-3).This study not only realized the real-time online measurement of multi-component polluted gas at the boundary of the industrial park but also built a point-line source diffusion model,combined with the field environment and portable FTIR measurement results to achieve the mixed determination of the concentration of polluted gas at the boundary of the factory.It provides an analytical thought for judging the future source of polluting gas at the boundary of the industrial park.