Effect of weathering behavior of polyethylene microplastics in water on coagulation process
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摘要:
以地表水中丰度较高的聚乙烯(PE)微塑料作为研究对象,开展吸附和混凝试验,在解析PE微塑料对水中有机物吸附能力的基础上,用氙灯对PE微塑料进行光老化以模拟微塑料在自然条件下的风化行为,深入研究PE微塑料风化行为对混凝过程的影响。结果表明:粒度为50~200目的PE微塑料对有机物的吸附量为310~350 mg/g(以碳计),不存在显著的吸附性能差异。在混凝过程中,相较于未添加PE微塑料的情况,添加未风化的PE微塑料会降低有机物去除率,而添加风化PE微塑料则能明显提升有机物去除率。同时,混凝过程对风化PE微塑料的去除率高于未风化PE微塑料,表明PE微塑料的风化行为有利于其在混凝过程中被去除。根据混凝过程中絮体特征可知,PE微塑料的风化行为对形成絮体的尺寸影响极小,但能显著提高絮体的生长速度。
Abstract:Polyethylene (PE) microplastics with high abundance in surface water were used as the research object to conduct adsorption and coagulation experiments. Based on the study regarding the organic matter adsorption capacity of PE microplastics, the effect of weathering behavior of PE microplastics on the coagulation process was further explored by using photoaged PE microplastics with xenon lamp to simulate weathering behavior of microplastics under natural conditions. The results showed that PE microplastics with particle size 50-200 mesh could adsorb 310-350 mg/g (calculated by carbon) organic matter, indicating that the microplastic size would not significantly influence the adsorption performance of PE microplastics. In coagulation, compared with no PE microplastics conditions, the addition of unweathered PE microplastics was prone to decrease the organic matter removal rate, while the addition of weathered PE microplastics was able to obviously increase the removal efficiency of organic matter. Furthermore, the removal rate of weathered PE microplastics was remarkably higher than that of unweathered PE microplastics in coagulation, which suggested that the weathering behavior was beneficial to PE microplastics removal during the coagulation process. According to the floc properties in coagulation, it was notable that both unweathered and weathered PE microplastics would not influence floc average size in coagulation, but significantly increased the growth rate of flocs in this process.
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表 1 混凝出水中PE微塑料数量及去除率
Table 1. Quantity and removal rate of PE microplastics in coagulated water
混凝剂投加量/
(mg/L)未风化PE微塑料 风化PE微塑料 数量/个 去除率/% 数量/个 去除率/% 15 56±3 5.90±1.37 26±2 48.40±1.88 20 44±4 22.64±1.91 22±0 55.86±2.65 25 38±2 36.70±2.51 20±5 59.61±4.24 30 16±3 72.66±1.65 11±2 80.13±1.31 35 46±6 23.30±2.98 24±3 53.30±3.98 -
[1] MA B W, XUE W J, HU C Z, et al. Characteristics of microplastic removal via coagulation and ultrafiltration during drinking water treatment[J]. Chemical Engineering Journal,2019,359:159-167. doi: 10.1016/j.cej.2018.11.155 [2] 姚皓文.废弃塑料泛滥危机的对策模型[J]. 中国资源综合利用,2020,38(6):69-71. doi: 10.3969/j.issn.1008-9500.2020.06.022YAO H W. The countermeasure model of waste plastic flooding crisis[J]. China Resources Comprehensive Utilization,2020,38(6):69-71. doi: 10.3969/j.issn.1008-9500.2020.06.022 [3] WANG C, XIAN Z Y, JIN X, et al. Photo-aging of polyvinyl chloride microplastic in the presence of natural organic acids[J]. Water Research,2020,183:116082. doi: 10.1016/j.watres.2020.116082 [4] 刘彬, 侯立安, 王媛, 等.我国海洋塑料垃圾和微塑料排放现状及对策[J]. 环境科学研究,2020,33(1):174-182. doi: 10.13198/j.issn.1001-6929.2019.07.05LIU B, HOU L A, WANG Y, et al. Emission estimate and countermeasures of marine plastic debris and microplastics in China[J]. Research of Environmental Sciences,2020,33(1):174-182. doi: 10.13198/j.issn.1001-6929.2019.07.05 [5] LEE Y K, HUR J. Adsorption of microplastic-derived organic matter onto minerals[J]. Water Research,2020,187:116426. doi: 10.1016/j.watres.2020.116426 [6] LEE Y K, ROMERA-CASTILLO C, HONG S, et al. Characteristics of microplastic polymer-derived dissolved organic matter and its potential as a disinfection byproduct precursor[J]. Water Research,2020,175:115678. doi: 10.1016/j.watres.2020.115678 [7] 王赛, 张岚, 陈永艳, 等.饮用水处理技术去除微塑料的效果及进展[J]. 净水技术,2021,40(10):20-25. doi: 10.15890/j.cnki.jsjs.2021.10.003WANG S, ZHANG L, CHEN Y Y, et al. Effect and progress of microplastics removal in drinking water treatment process[J]. Water Purification Technology,2021,40(10):20-25. doi: 10.15890/j.cnki.jsjs.2021.10.003 [8] 赵艳民, 马迎群, 温泉, 等.基于不确定性的天津市北塘排污河表层沉积物微塑料污染评价[J]. 环境工程技术学报,2021,11(3):554-561. doi: 10.12153/j.issn.1674-991X.20200098ZHAO Y M, MA Y Q, WEN Q, et al. Evaluation of microplastics pollution in surface sediments of Beitang Drainage River in Tianjin City based on uncertainty[J]. Journal of Environmental Engineering Technology,2021,11(3):554-561. doi: 10.12153/j.issn.1674-991X.20200098 [9] HERNANDEZ E, NOWACK B, MITRANO D M. Polyester textiles as a source of microplastics from households: a mechanistic study to understand microfiber release during washing[J]. Environmental Science & Technology,2017,51(12):7036-7046. [10] SKAF D W, PUNZI V L, ROLLE J T, et al. Removal of micron-sized microplastic particles from simulated drinking water via alum coagulation[J]. Chemical Engineering Journal,2020,386:123807. doi: 10.1016/j.cej.2019.123807 [11] NELMS S E, BARNETT J, BROWNLOW A, et al. Microplastics in marine mammals stranded around the British coast: ubiquitous but transitory[J]. Scientific Reports,2019,9:1075. doi: 10.1038/s41598-018-37428-3 [12] MOORE R C, LOSETO L, NOEL M, et al. Microplastics in beluga whales (Delphinapterus leucas) from the eastern Beaufort Sea[J]. Marine Pollution Bulletin,2020,150:110723. doi: 10.1016/j.marpolbul.2019.110723 [13] 赵美静, 夏斌, 朱琳, 等.微塑料与有毒污染物相互作用及联合毒性作用研究进展[J]. 生态毒理学报,2021,16(5):168-185.ZHAO M J, XIA B, ZHU L, et al. Research progress on interaction and joint toxicity of microplastics with toxic pollutants[J]. Asian Journal of Ecotoxicology,2021,16(5):168-185. [14] PRATA J C, da COSTA J P, LOPES I, et al. Environmental exposure to microplastics: an overview on possible human health effects[J]. Science of the Total Environment,2020,702:134455. doi: 10.1016/j.scitotenv.2019.134455 [15] STRAK M, JANSSEN N A H, GODRI K J, et al. Respiratory health effects of airborne particulate matter: the role of particle size, composition, and oxidative potential-the RAPTES project[J]. Environmental Health Perspectives,2012,120(8):1183-1189. doi: 10.1289/ehp.1104389 [16] XU H Y, VERBEKEN E, VANHOOREN H M, et al. Pulmonary toxicity of polyvinyl chloride particles after a single intratracheal instillation in rats: time course and comparison with silica[J]. Toxicology and Applied Pharmacology,2004,194(2):111-121. doi: 10.1016/j.taap.2003.09.018 [17] 张嘉戌, 邓义祥, 张承龙, 等.基于环境行为理论的公众一次性塑料减量政策研究[J]. 环境工程技术学报,2021,11(5):888-897. doi: 10.12153/j.issn.1674-991X.20200300ZHANG J X, DENG Y X, ZHANG C L, et al. Study on the public single-use plastics reduction policies based on the theory of environmental behaviors[J]. Journal of Environmental Engineering Technology,2021,11(5):888-897. doi: 10.12153/j.issn.1674-991X.20200300 [18] 荣佳辉, 牛学锐, 韩美, 等.河流微塑料入海通量研究进展[J]. 环境科学研究,2021,34(7):1630-1640. doi: 10.13198/j.issn.1001-6929.2020.12.21RONG J H, NIU X R, HAN M, et al. Global river microplastics flux into the sea: a review[J]. Research of Environmental Sciences,2021,34(7):1630-1640. doi: 10.13198/j.issn.1001-6929.2020.12.21 [19] HAN M, NIU X R, TANG M, et al. Distribution of microplastics in surface water of the lower Yellow River near estuary[J]. Science of the Total Environment,2020,707:135601. doi: 10.1016/j.scitotenv.2019.135601 [20] 李高俊, 熊雄, 詹晨熙, 等.南渡江水体微塑料污染现状研究[J]. 环境科学学报,2022,42(2):205-212.LI G J, XIONG X, ZHAN C X, et al. Occurrence of microplastics in the water of the nandu Jiang River[J]. Acta Scientiae Circumstantiae,2022,42(2):205-212. [21] 周叶, 高峰, 戚雷强.混凝水处理法应用现状及强化措施探讨[J]. 净水技术,2021,40(增刊 1):9-14. doi: 10.15890/j.cnki.jsjs.2021.s1.003ZHOU Y, GAO F, QI L Q. Discussion on application status and improvement measures of coagulation technology for water treatment[J]. Water Purification Technology,2021,40(Suppl 1):9-14. doi: 10.15890/j.cnki.jsjs.2021.s1.003 [22] WANG W Y, YUE Q Y, GUO K Y, et al. Application of Al species in coagulation/ultrafiltration process: influence of cake layer on membrane fouling[J]. Journal of Membrane Science,2019,572:161-170. doi: 10.1016/j.memsci.2018.11.014 [23] 徐琪珂, 戴红玲, 赵国强, 等.微涡流絮凝工艺处理高浊水的数值模拟与响应面优化试验[J]. 环境工程技术学报,2022,12(1):62-69. doi: 10.12153/j.issn.1674-991X.20210620XU Q K, DAI H L, ZHAO G Q, et al. Numerical simulation and response surface optimization of micro-vortex flocculation process for high turbidity water treatment[J]. Journal of Environmental Engineering Technology,2022,12(1):62-69. doi: 10.12153/j.issn.1674-991X.20210620 [24] YEANG H Y. Synchronous flowering of the rubber tree (Hevea brasiliensis) induced by high solar radiation intensity[J]. The New Phytologist,2007,175(2):283-289. doi: 10.1111/j.1469-8137.2007.02089.x [25] CLASEN J, MISCHKE U, DRIKAS M, et al. An improved method for detecting electrophoretic mobility of algae during the destabilisation process of flocculation: flocculant demand of different species and the impact of DOC[J]. Journal of Water Supply:Research and Technology-Aqua,2000,49(2):89-101. doi: 10.2166/aqua.2000.0008 [26] GAFFNEY J, MARLEY N, CLARK S. Humic and fluvic acids and organic colloidal materials in the environment[M]. Washington DC: ACS Symposium Series, American Chemical Society, 1996. [27] 孙璇, 俞安琪, 王学松, 等.富里酸在聚苯乙烯微塑料上的吸附行为[J]. 中国环境科学,2022,42(1):285-292. doi: 10.3969/j.issn.1000-6923.2022.01.031SUN X, YU A Q, WANG X S, et al. Adsorption behaviors of fulvic acid onto polystyrene microplastics[J]. China Environmental Science,2022,42(1):285-292. doi: 10.3969/j.issn.1000-6923.2022.01.031 [28] LARCHÉ J F, BUSSIÈRE P O, THÉRIAS S, et al. Photooxidation of polymers: relating material properties to chemical changes[J]. Polymer Degradation and Stability,2012,97(1):25-34. doi: 10.1016/j.polymdegradstab.2011.10.020 [29] 张桂芝, 杨清伟, 蹇徽龙, 等.水环境中微塑料对典型污染物的吸附行为研究进展[J]. 应用化工,2022,51(1):246-250. doi: 10.3969/j.issn.1671-3206.2022.01.051ZHANG G Z, YANG Q W, JIAN H L, et al. Research progress on the adsorption behavior of typical pollutants by microplastics in water environment[J]. Applied Chemical Industry,2022,51(1):246-250. doi: 10.3969/j.issn.1671-3206.2022.01.051 [30] 吴小伟, 黄何欣悦, 石妍琦, 等.水环境中微塑料的光老化过程及影响因素研究进展[J]. 科学通报,2021,66(36):4619-4632. doi: 10.1360/TB-2021-0376WU X W, HUANG H X Y, SHI Y Q, et al. Progress on the photo aging mechanism of microplastics and related impact factors in water environment[J]. Chinese Science Bulletin,2021,66(36):4619-4632. ⊗ doi: 10.1360/TB-2021-0376