Abstract:

To resolve the core contradiction between “emission increment-carrying capacity threshold” in the Zhoushan Archipelago New Area, this study takes the region as the research object. Based on the WRF-CAMx coupled model, and by integrating 2022 ambient air quality data, air pollution source inventories, and projected emission increments from planning scenarios, it quantifies the monthly atmospheric environmental capacity of SO₂, NO_x, and VOCs under the constraint of PM_2.5 (with a control target of 20 µg·m⁻³). The results show that, 1) In 2022, pollutant emissions in Zhoushan exhibited distinct industry-specific characteristics. The annual NO_x emission was 30076 tons per year (t·a⁻¹), of which 60.3% came from portside marine diesel engines and 17.3% from coal-fired power plants. The annual VOCs emission was 44562 t·a⁻¹, with 70% derived from petrochemical processes and solvent use in the shipbuilding and repair industry. 2) Environmental capacity calculations indicate that under the baseline scenario (Scenario A, current emissions): when considering individual pollutant increments, the allowable additional emissions of NO_x, VOCs, and SO₂ were 30859 t·a⁻¹, 40117 t·a⁻¹, and 11436 t·a⁻¹, respectively; when considering the synergistic increment of the three pollutants, the allowable additional emissions were 16842, 22081, and 9276 t·a⁻¹, respectively, with no environmental capacity available only in January and December. Under the enhanced baseline scenario (Scenario B, incorporating planned emission increments: 8413 t·a⁻¹ for SO₂, 17299 t·a⁻¹ for NO_x, and 2006 t·a⁻¹ for VOCs): When considering individual pollutant increments, the allowable additional emissions of the three pollutants decreased to 9237, 12015, and 4892 t·a⁻¹, respectively; when considering synergistic increment, the values dropped to 5053, 6631, and 2998 t·a⁻¹, respectively. No environmental capacity was available throughout the entire winter (January-February and December). 3) A PM_2.5 concentration of 23 µg·m⁻³ was identified as the critical threshold: when PM_2.5 concentrations were below this value, the environmental carrying capacity was dominated by local emissions; when concentrations exceeded this value, the impact of regional pollution input became significant. The results demonstrate that the atmospheric environmental carrying capacity of the Zhoushan Archipelago New Area is generally consistent with existing plans. Targeted measures such as zoned management and control, staggered production, and regional joint prevention are required to enhance this carrying capacity.

Key words: atmospheric environmental carrying capacity, nitrogen oxides, volatile organic compounds, coordinated control of fine particles, Zhoushan Harbor-front Industrial Zone

摘要：

为破解大气污染物排放增量与环境承载力阈值之间的核心矛盾，以舟山群岛新区为对象，基于WRF-CAMx耦合模型，结合2022年环境空气质量数据、大气污染源清单及规划情景排放增量，按月量化PM_2.5（管控目标20 µg·m⁻³）约束下SO₂、NO_x、VOCs的大气环境容量。结果显示：舟山2022年污染物排放具有显著的产业指向性，NO_x排放量30076 t·a⁻¹（60.3%来自临港船舶柴油机；17.3%来自燃煤电厂），VOCs排放量44562 t·a⁻¹（70%来自石化工艺与修造船溶剂使用）；环境容量测算表明，基准情景（A，现状排放）下，单独排放时NO_x、VOCs、SO₂可新增排放量分别为30859、40117、11436 t·a⁻¹，协同排放时分别为16842、22081、9276 t·a⁻¹，且仅1、12月无环境容量；增强基准情景（B，叠加规划增量：SO₂为8413 t·a⁻¹，NO_x为17299 t·a⁻¹，VOCs为2006 t·a⁻¹）下，单独排放时三类污染物可新增排放量降至9237、12015、4892 t·a⁻¹，协同排放时降至5053、6631、2998 t·a⁻¹，且整个冬季（1－2月、12月）均无环境容量；23 µg·m⁻³为PM_2.5质量浓度临界阈值，低于此阈值承载力受本地排放主导，高于阈值时受区域污染输入影响显著。舟山群岛新区大气环境承载力与现有规划基本协调，需通过分区管控、错峰生产、区域联防等精准措施提升承载力。

关键词: 大气环境承载力, 氮氧化物, 挥发性有机物, 大气细颗粒物协同控制, 舟山临港工业区