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951.
低压膜过滤技术(包括微滤和超滤)在再生水生产领域正引起越来越广泛的关注。然而如何解决低压膜过滤过程中的膜有机污染问题始终是膜技术所面临的技术挑战。本研究采用醋酸纤维素酯微孔滤膜对二级出水溶解性有机物(EfOM)及其不同亲疏水性组分、蛋白模拟溶液、腐殖酸(HA)等进行恒流过滤实验。对不同有机物污染后的膜表面使用全反射傅立叶红外光谱(ATR-FTIR)和X射线电子能谱(XPS)进行表征。结果表明,相对于蛋白质和EfOM等,HA所造成的膜污染最少。ATR-FTIR的结果同时显示,以官能团而言,更多的氨化物(1535cm-1)、脂肪族物质(2860~2970cm-1)和氢氧根(3400cm-1)存在于膜表面。TMP/V数据比较结果表明,在EfOM各亲疏水性组分、蛋白质和HA的对比中,EfOM中的疏水碱性物质(HPO-B)对膜污染的贡献最大,而HA的膜污染贡献最小。UVA和荧光激发-发射光谱(FEEM)结果表明,HPO-B和蛋白质对醋酸纤维素酯膜的污染贡献较大。综合不同分析手段可以对不同有机物造成膜污染的潜能大小得出如下排序:HPO-B>蛋白质>HPO-A、HPI>HA。 相似文献
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利用现有装备处理钻井废水,处理后的水质已不能满足2000年企业污染物排放达标的规定要求。川东钻探公司从美国引进了Hydrocal钻井污水处理系统,对目前石油系统钻井废水普遍存在的技术问题进行了探讨,提出了应借鉴国外钻井污水处理系统的优点。建议钻井废水处理装备的研制仍然应采用提高混凝沉淀效果、固液分离水平及控制水平等 相似文献
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Mengke Zhu Bocong Huang Shenghao Ai Zongyang Liu Xiaoyan Ai Meihua Sheng Yingwei Ai 《Frontiers of Environmental Science & Engineering》2023,17(4):42
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This study focuses on the effects of pH and fluoride at different molar ratios of fluoride to Al (RF:Al) on the removal of cadmium (Cd2+) and phosphate by Al coagulation. Fluoride at RF:Al ≥ 3:1 inhibits the removal of Cd over wide Al dose ranges from 5 to 10 mg/L as Al. The removal of phosphate decreases significantly at high RF:Al of 10:1 whereas at lowered RF:Al (i.e., ≤ 6:1), an adverse effect is observed only at insufficient Al doses below 2 mg/L. Fluoride shows inhibitive effects towards the removal of Cd at pH 7 and 8 and that of phosphate at pH 6. Fluoride decreases the ζ-potential in both systems, and the decreasing extent is positively correlated to the elevated RF:Al. The Al fluoride interactions include the formation of Al–F complexes and the adsorption of fluoride onto Al(OH)3 precipitates, i.e., the formation of Al(OH)nFm. Al–F complex formation inhibits Al hydrolysis and increases residual Al levels, and a more significant increase was observed at lower pH. Al–F complexes at high RF:Al complicate the coagulation behavior of Al towards both negative and positive ionic species. Moreover, fluoride at low RF:Al shows little effect on Al coagulation behavior towards Cd2 + and phosphate, and the spent defluoridation adsorbent, i.e., aluminum (Al) hydro(oxide) with adsorbed fluoride at RF:Al of below 0.1:1, may be reclaimed as a coagulant after being dissolved. 相似文献
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Ruihan Zong Xue Yang Liang Wen Caihong Xu Yanhong Zhu Tianshu Chen Lan Yao Liwei Wang Junmei Zhang Lingxiao Yang Xinfeng Wang Min Shao Tong Zhu Likun Xue Wenxing Wang 《环境科学学报(英文版)》2018,30(9):261-270
Regional ozone (O3) pollution has drawn increasing attention in China over the recent decade, but the contributions from urban pollution and biogenic emissions have not been clearly elucidated. To better understand the formation of the regional O3 problem in the North China Plain (NCP), intensive field measurements of O3 and related parameters were conducted at a rural site downwind of Ji'nan, the capital city of Shandong province, in the summer of 2013. Markedly severe O3 pollution was recorded, with the O3 mixing ratios exceeding the Chinese national ambient air quality standard on 28?days (a frequency of 78%) and with a maximum hourly value of 198 ppbv. Extensive regional transport of well-processed urban plumes to the site was identified. An observation-constrained chemical box model was deployed to evaluate in situ photochemical O3 production on two episodes. The results show that the in situ formation accounted for approximately 46% of the observed O3 accumulation, while the remainder (~ 54%) was contributed by regional transport of the O3-laden urban plumes. The in situ ozone production was in a mixed controlled regime that reducing either NOx or VOCs would lead to a reduction of ozone formation. Biogenic VOCs played an important role in the local ozone formation. This study demonstrates the significant mixed effects of both anthropogenic pollution from urban zones and biogenic emission in rural areas on the regional O3 pollution in the NCP region, and may have general applicability in facilitating the understanding of the formation of secondary pollution over China. 相似文献
960.
垃圾填埋场渗滤液成分复杂,其氨氮的测定干扰物质多,测定难度大.气相分子吸收光谱法是一种较为新兴的方法,通过对气相分子吸收光谱法和传统纳氏试剂分光光度法系统的比较,研究气相分子吸收光谱法测定垃圾填埋场渗滤液中氨氮的分析方法.结果表明,气相分子吸收光谱法测定垃圾填埋场渗滤液中氨氮操作便捷、干扰小、精密度好,中浓度与高浓度废水测定结果能较好的与纳氏试剂光度法测定结果法吻合,超低浓度废水的测定结果低于纳氏试剂分光光度法.为监测工作者分析方法的选择提供依据. 相似文献