印染废水处理提标小试研究

利用"水解酸化+强化好氧+深度处理"的工艺技术方案开展印染废水小试研究。在工艺前端采用混流式和升流式两级水解酸化池,后续在曝气池投加活性焦载体,提高污泥浓度,强化好氧池处理能力,最后对生化出水加药混凝,并用生物活性焦滤池进行深度处理。结果表明,该处理工艺适宜处理印染废水,处理效果达到处理提标要求。     

长株潭地区秋冬季环境空气质量分析及与气象参数的关联性研究

以湖南省长株潭3市为研究区域,分析其在2013年第4季度的城市环境空气质量状况,并与上年同期进行对比,同时研究PM_2.5质量浓度和AQI值与气象参数的相关性。结果表明,PM₁₀和PM_2.5是长株潭3市的主要大气污染物;2013年第4季度中,长株潭3市在11月份的空气质量最好;总体上,3市中,湘潭市的空气质量最差,而3市2013年第4季度的环境空气质量较上年同期明显下降,复合污染特征越来越明显。PM_2.5质量浓度和AQI值与气象参数都有一定的相关性,尤其是与能见度显著负相关,与风速、湿度和气压微弱负相关,而与温度微弱正相关。与上年同期相比,长株潭3市在2013年第4季度的气温偏高,湿度较小,平均风速小,气象条件不利于大气污染物扩散。因此,尽管3市的污染治理力度大,减排成效明显,但城市环境空气质量反而较上年同期下降。在大气环境容量基本利用殆尽的情况下,不利气象条件随时可能直接诱发严重的大气污染问题。     

Extraction of heavy metals from e-waste contaminated soils using EDDS

Environmental contamination due to uncontrolled e-waste recycling activities is drawing increasing attention in the world. Extraction of these metals with biodegradable chelant [S,S]-ethylenediaminedisuccinic acid (EDDS) and the factors influencing extraction efficacy were investigated in the present study. Results showed that the addition of EDDS at low pH (5.5) produced higher metal extraction than that at high pH (8.0) solution. Metal speciation analysis indicated that Cu was completely complexed with EDDS at different pH conditions with various amounts of EDDS applied. For Pb and Zn, at low EDDS dose of 0.304 mol/kg soil, they were present as Pb- and Zn-EDDS. However, at high EDDS dose of 1.26 mol/kg soil, most of Pb was bound with dissolved organic matter. Ca and Al were found to be strong competitors for trace metals to EDDS at low application dose and low pH condition.     

A review of polybrominated diphenyl ethers and alternative brominated flame retardants in wildlife from China: Levels, trends, and bioaccumulation characteristics

Accelerated industrialization and urbanization, and unregulated disposal of waste of electric and electronic equipment (e-waste) in China have caused environmental pollution of brominated flame retardants (BFRs). This review summarized the levels, trends, and bioaccumulation characteristics of polybrominated diphenyl ethers (PBDEs) and other potential alternative BFRs including hexabromocyclododecanes (HBCDs), 1,2-bis(2,4,6-dibromophenoxy) ethane (BTBPE) and decabromodiphenylethane (DBDPE) in wildlife from China. PBDE levels in wildlife from China were generally higher than those from other parts in Asia, and were comparable to those from Europe but were lower than those from North America. However, wildlife from the e-waste recycling sites in South China and East China contained much higher PBDEs compared to other reports around the world, suggesting the heavy contamination of PBDEs in these regions. The alternative BFRs were also detected in wildlife, revealing that the animals are exposed to these chemicals, in addition to PBDEs. Temporal trends indicated by levels in marine mammals from South China suggested that PBDE levels increased from the beginning of 1990s to 2000s, but decreased from the middle of 2000s, followed by relatively steady levels. In contrast, HBCDs were found to be continuously increasing from 1997 to 2007, indicating the increasing usage of HBCDs in China in recent years. Compared to PBDE profiles found in other parts, aquatic species and birds from China contained relatively higher contributions of BDE-28 and 209, respectively, suggesting the possible different usage pattern of PBDEs. Future works including keeping monitoring at a reasonable scale and frequency to make sure levels near urban centers indicative of population do not increase are needed. Additionally, focus effort on e-waste recycling regions to look for impacts and to determine if regulation/controls are resulting in lower environmental contamination, and incorporation of sentinel species in monitoring efforts are recommended.     

Identification of close relationship between atmospheric oxidation and ozone formation regimes in a photochemically active region

Understanding ozone (O₃) formation regime is a prerequisite in formulating an effective O₃ pollution control strategy. Photochemical indicator is a simple and direct method in identifying O₃ formation regimes. Most used indicators are derived from observations, whereas the role of atmospheric oxidation is not in consideration, which is the core driver of O₃ formation. Thus, it may impact accuracy in signaling O₃ formation regimes. In this study, an advanced three-dimensional numerical modeling system was used to investigate the relationship between atmospheric oxidation and O₃ formation regimes during a long-lasting O₃ exceedance event in September 2017 over the Pearl River Delta (PRD) of China. We discovered a clear relationship between atmospheric oxidative capacity and O₃ formation regime. Over eastern PRD, O₃ formation was mainly in a NO_x-limited regime when HO₂/OH ratio was higher than 11, while in a VOC-limited regime when the ratio was lower than 9.5. Over central and western PRD, an HO₂/OH ratio higher than 5 and lower than 2 was indicative of NO_x-limited and VOC-limited regime, respectively. Physical contribution, including horizontal transport and vertical transport, may pose uncertainties on the indication of O₃ formation regime by HO₂/OH ratio. In comparison with other commonly used photochemical indicators, HO₂/OH ratio had the best performance in differentiating O₃ formation regimes. This study highlighted the necessities in using an atmospheric oxidative capacity-based indicator to infer O₃ formation regime, and underscored the importance of characterizing behaviors of radicals to gain insight in atmospheric processes leading to O₃ pollution over a photochemically active region.     

Utilization of coal fly ash in China: a mini-review on challenges and future directions

Environmental Science and Pollution Research - The rapid economic development in China places a large demand for energy, and as a result, thermal power plants in China are producing an enormous...     

The improved activity of Co3O4 nanorods using silver in the catalytic oxidation of toluene

Environmental Science and Pollution Research - Co3O4 nanorods with diameters of ~0.15 μm and lengths of ~1 μm were prepared using a hydrothermal method via the assembly of microcrystals...     

Groundwater geochemical signatures and implication for sustainable development in a typical endorheic watershed on Tibetan plateau

Environmental Science and Pollution Research - Groundwater resource is significantly important for sustainable development of the world, especially for arid endorheic watersheds. A total of 28...     

一种生物除臭方法及装置的研究

文章介绍了一种生物除臭的方法,这种方法是将装有碳质填料的反应包悬挂于好氧池中,反应包在好氧池中,历经曝气挂膜20~30天;就可以将装有碳质填料的反应包/或碳质填料放于生物除臭装置内;然后向生物除臭装置通入湿润的臭气,就可以将其生成水、二氧化碳、硫酸、硝酸和亚硝酸.使臭气被氧化,转化成无污染的物质,由于它的转化效率高,符合现代生产的高效性,因此一定会在生产实际中受到欢迎.     

兰州市废旧手机产生量预测分析研究

手机普及率日益提高,随之产生的废弃量也日益增多,分别采用时间梯度模型、市场供给A模型、斯坦福(stanford)模型对兰州市2013年-2022年废旧手机的产生量进行了预测.结果显示,不同模型预测结果之间存在较大差异,市场供给A模型和斯坦福(Stanford)模型的预测结果比较接近,均大于时间梯度模型的预测结果,三种模型预测的兰州市2022年废旧手机的产生量分别为40.40万、46.67万和21.04万部.总体上看,兰州市废旧手机的产生量增长趋势较快.