摘要
危险化学品在海水中的衰减特征对于其泄漏事故发生后采取针对性应急对策十分重要。为了探究泄漏入海的正丙苯(n-PBZ)和异丙苯(i-PBZ)衰减程度随环境条件的变化趋势,采用微宇宙实验方法分别调节温度、盐度、pH、光强和风速,根据海水中n-PBZ和i-PBZ的浓度变化进行衰减动力学分析,确定影响较大的环境因子以及低风速对二者衰减的不利影响。研究表明,温度是对2种丙苯(PBZs)衰减影响最大的环境因子,其与衰减速率常数(k)呈显著正相关:n-PBZ和i-PBZ在30℃下的k值分别为5℃下的2.12和1.90倍。光照有利于n-PBZ和i-PBZ衰减,2种PBZs在光强800μmol/(m^(2)·s)时的k值分别为黑暗条件下的1.63和1.57倍。仅在较低盐度(≤10)时,k值随盐度增加而增大。海水的pH(6~9)对2种PBZs的衰减均无显著影响。常见于海雾天气的低风速(1 m/s)非常不利于n-PBZ和i-PBZ衰减,风速1 m/s时n-PBZ和i-PBZ的k值不足风速5 m/s时的60%,这将造成事故海域在较长时间(20 d以上)面临中、高生态风险。研究结果表明,温度、光强和风速是影响海水中n-PBZ和i-PBZ自然衰减的主要环境因子。
The attenuation characteristics of hazardous chemicals in seawater are crucial for taking targeted emergency measures after their leakage accident occurs.In order to investigate the attenuation trend of n-phenylbenzene(n-PBZ)and isopropylbenzene(i-PBZ)spilled into the sea with changes in environmental conditions,a microcosm system was used to adjust temperature,salinity,pH,light intensity,and wind speed,respectively.Based on the concentration changes of n-PBZ and i-PBZ in seawater,attenuation kinetics analysis was conducted to determine the environmental factors that had a significant impact and the adverse effects of low wind speed on their attenuation.The results showed that temperature was the factor that had the greatest impact on the attenuation of each propylbenzene with a significantly positive correlation with the attenuation rate constant(k).The k values of n-PBZ and i-PBZ at 30℃were 2.11 and 1.90 times higher than those at 5℃,respectively.Illumination was also beneficial for the attenuation of n-PBZ and i-PBZ.The k value at light intensity of 800μmol/(m^(2)·s)were 1.63 and 1.57 times higher than those under dark conditions,respectively.At lower salinity,the k value increased with the increase of salinity,but remained stable at salinity≥10.The change in seawater pH value(6~9)had no significant effect on the attenuation of propylbenzene.The low wind speed(1 m/s)commonly seen in foggy weather was very unfavorable for the attenuation of n-PBZ and i-PBZ with the k value less than 60%of those at a wind speed of 5 m/s,resulting in the accident area at medium to high ecological risks for a long period(over 20 days).Our findings demonstrated that temperature,light intensity,and wind speed are the main environmental factors affecting the natural attenuation of n-PBZ and i-PBZ in seawater.
作者
陈汕
夏宇凡
孟范平
Chen Shan;Xia Yufan;Meng Fanping(Key Laboratory of Marine Environment and Ecology,Ministry of Education,Ocean University of China,Qingdao 266100,China;College of Environmental Science and Engineering,Ocean University of China,Qingdao 266100,China)
出处
《中国海洋大学学报(自然科学版)》
北大核心
2025年第9期114-124,共11页
Periodical of Ocean University of China
基金
国家自然科学基金项目(42077335)资助。
关键词
正丙苯
异丙苯
衰减
温度
光强
低风速
微宇宙
n-propylbenzene
isopropylbenzene
attenuation
temperature
light intensity
low wind speed
microcosm system
