土壤中结合态苯氧羧酸类除草剂的测定

利用超临界ＣＯ２流体萃取的方法提取２甲４氯(ＭＣＰＡ),２,４－Ｄ和除草醚在三种土壤中的结合残留．结果表明,在培养２００ｄ的时间内,ＭＣＰＡ的结合残留量为１．０ｌ－５．１２ｍｇ·ｋｇ－１,占添加总量的２．０－１０．１%;２,４－Ｄ的结合残留量为０．２４－２．６５ｍｇ·ｋｇ－１,占添加总量的０．５－５．３%;除草醚的结合残留量为６．５３－１９．３０ｍｇ·ｋｇ－１,占添加总邑的１２．９—３８．２%．农药结合态与游离态含量的比值随时间的延长而增加．     

金属离子协同马尾藻对水中偶氮染料分子脱色的研究

本文研究了多种金属离子对海藻处理不同结构的偶氮染料分子的影响，结果表明，金属离子的种类及浓度对海藻处理偶所染料都有重要的作用，偶氮染料的分子量和结构也影响该体系的脱色效果。适当浓度的金属离子和海藻的体系比单独海藻处理偶氮染料的脱色速度快，脱色率高。同时探讨了该体系处理不同结构染料分子的脱色差异。     

利用城市污泥防治水土流失

根据城市污泥的特点,分析了城市污泥在改良土壤和防治水土流失上应用的必要性和可能性,指出了存在的问题和对策。     

环境友好型淋洗剂对重金属污染土壤的修复效果

以广西某废弃铅锌冶炼企业重金属复合污染土壤为对象,采用土柱淋洗的方法,分别将自制的茶皂素、柠檬酸和EDTA 3种淋洗剂进行复合淋洗,并对复合淋洗的最佳配比、淋洗剂添加方式和淋洗时间进行研究,得到对环境友好且淋洗效果好的复合淋洗剂。最后,对淋洗前后土壤中Cu、Pb和Zn的赋存形态进行研究,探讨淋洗机理。研究结果表明,茶皂素和柠檬酸复合时对重金属Cu、Pb、Zn的去除率分别达到了77.00%、52.09%和58.66%,综合考虑淋洗效率以及经济环保等因素,选择将茶皂素和柠檬酸复合进行淋洗。复合淋洗实验结果表明,柠檬酸和茶皂素体积比为3：1复合方式淋洗30 h,淋洗效果最佳,对重金属Cu、Pb和Zn的去除率分别达到82.77%、65.49%和78.12%。茶皂素和柠檬酸复合淋洗能有效的去除土壤中酸可提取态和有机结合态的重金属,氧化物结合态的Pb和Zn也有较大程度的降低,同时还发现,茶皂素和柠檬酸共同作用对残余态的Pb去除效果也较好,可达到50%以上。从茶籽饼中提取茶皂素与天然有机酸柠檬酸复合淋洗,用于修复污染面积小、污染浓度高且污染比较集中的重金属污染土壤,效果好且对环境友好。     

The transportation,time-dependent distribution of heavy metals in paddy crops

Sixteen experimenmtal plots (5 m x 6 m = 30 m2) were designed with four different levels of heavy metals (HMs) concentration in soil. The concentrations of heavy metals in soils, and paddy plant during the different periods of growth were investigated. A relationship between the total HM content in plants and the HM level in soil was found for a wide range of concentrations. The exchangeable fraction of HMs extracted with 1 M MgCl2 solution according to Tessier's method increased correlation with the dosage of supplemented HMs, then decreased as time went on. The time-related variation of exchangeable HMs in soil demonstrated that the amount of effective HMs taken up by paddy differed at various growth phases. The amount of HMs accumulated in different parts of paddy followed the order of root > stem > grain, leaf. The transportation potential of the HMs in paddy in present study followed the order of Zn, Cr > Cd, Cu > Pb. The HM content in root, stem and leaf of paddy plant (dry weight) was low at time of seedling. The concentration in the root increased sharply at time of tillering, decreased thereafter. The concentrations in stem and leaf reached the highest at time of tillering, then decreased, while rose slightly at following time.     

Particle-bound Dechlorane Plus and polybrominated diphenyl ethers in ambient air around Shanghai, China

In present study, atmospheric particles from Shanghai, the biggest city and the most important industrial base in China, were analyzed for polybrominated diphenyl ethers (PBDEs) and Dechlorane Plus (DP). Concentrations of ∑(20)PBDEs and DP both exhibited the changing trend of industrial area > urban areas. Jiading District had the highest levels of particulate PBDEs and DP with values of 744 ± 152 pg/m(3) and 5.48 ± 1.28 pg/m(3), respectively. Compared with similar data in other areas of the world, PBDEs in Shanghai were at medium pollution level, while DP was at lower level, which reflected their different production and use in Shanghai. The results from multiple linear regression analysis suggested that deca-BDE mixture was the most important contributor of particulate PBDEs in Shanghai. The fractions of anti-DP showed no significant differences to those of the technical mixtures (p > 0.05), which suggested that no obviously stereoselective process occurred in ambient air around Shanghai.     

磁性活性炭的制备及其对水中甲基橙的吸附

活性炭被广泛应用于水处理领域,然而吸附饱和后难以分离和再生的缺点却限制了其应用。本研究采用化学共沉淀法将铁氧化物和活性炭进行复合,制备出同时具有磁分离性能和较强的吸附性能的磁性活性炭复合材料,并对制备的复合材料进行表征,考察其对水中甲基橙的吸附性能。结果表明,制备的磁性活性炭的比表面积为666.72 m2/g,平均孔径为3.16 nm,具有良好的磁性能,在外加磁场下能快速地从溶液中分离出来且磁性能相对稳定,铁氧化物对活性炭吸附性能的影响不大。在温度为25℃、pH为5、吸附剂用量为3 g/L的情况下,吸附3 h后,该磁性活性炭对甲基橙的吸附率可达99.1%,预示着该磁性活性炭在水处理方面具有潜在的应用前景。     

采气废水中有机物去除方法

新疆油田天然气开采过程中产生的大量高矿化度、高COD的含油废水,难以处理处置,严重影响了气田的正常生产活动,危害到气田周边土壤安全和荒漠植被的生存。为实现该类废水的达标排放,选取COD和总石油烃含量为考察指标,研究比较了紫外(UV)、臭氧(O3)及紫外臭氧联合处理(UV/O3)法对该类废水的处理效果,进一步考察了pH和O3发生量对UV/O3法处理效果的影响。研究结果表明,3种方法处理废水60 min后,废水COD由处理前的563 mg/L分别下降至处理后的479、334.9和314 mg/L,去除率分别达到14.9%、32.7%和44.2%;而总石油烃含量由处理前的3.86 mg/L分别降至处理后的3.05、1.26和0.20 mg /L,去除率分别达到21.2%、67.4%和94.8%;其中,UV/O3法处理90 min后废水COD降低至148 mg/L,达到《废水综合排放标准GB8978-1996》二级排放标准;pH为7,臭氧发生量为10 g/L时,UV/O3法可应用于采气废水的处理。     

Preparation of a new Fenton-like catalyst from red mud using molasses wastewater as partial acidifying agent

Using molasses wastewater as partial acidifying agent, a new Fenton-like catalyst (ACRM _sm ) was prepared through a simple process of acidification and calcination using red mud as main material. With molasses wastewater, both the free alkali and the chemically bonded alkali in red mud were effectively removed under the action of H₂SO₄ and molasses wastewater, and the prepared ACRM _sm was a near-neutral catalyst. The ACRM _sm preparation conditions were as follows: for 3 g of red mud, 9 mL of 0.7 mol/L H₂SO₄ plus 2 g of molasses wastewater as the acidifying agent, calcination temperature 573 K, and calcination time 1 h. Iron phase of ACRM _sm was mainly α-Fe₂O₃ and trace amount of carbon existed in ACRM _sm . The addition of molasses wastewater not only effectively reduced the consumption of H₂SO₄ in acidification of red mud but also resulted in the generation of carbon and significantly improved the distribution of macropore in prepared ACRM _sm . It was found that near-neutral pH of catalyst, generated carbon, and wide distribution of macropore were the main reasons for the high catalytic activity of ACRM _sm . The generated carbon and wide distribution of macropore were entirely due to the molasses wastewater added. In degradation of orange II, ACRM _sm retained most of its catalytic stability and activity after five recycling times, indicating ACRM _sm had an excellent long-term stability in the Fenton-like process. Furthermore, the performance test of settling showed ACRM _sm had an excellent settleability. ACRM_sm was a safe and green catalytic material used in Fenton-like oxidation for wastewater treatment.

     

基于演化博弈视角的中国废铅蓄电池回收利用过程主要问题分析和对策研究

我国铅蓄电池每年的报废量十分庞大,其不正规回收利用给环境带来了严重污染。近年来,国家为规范废铅蓄电池的回收利用已出台多项政策,但行业内部仍存在许多问题。基于调研说明了废铅蓄电池回收利用的现状,阐述了回收利用过程中的电池流向和保障机制。基于废铅蓄电池回收利用过程各利益相关方复杂的博弈关系引入演化博弈模型,从模型构建、求解和结果可视化几方面说明演化博弈的流程。通过梳理废铅蓄电池回收利用过程中各利益相关方的矛盾冲突,针对正规回收、生产者延伸责任落实、正规再生利用等方面构建三方演化博弈模型。最后,结合模型分析提出相应建议,包括强化物联网技术的应用、出台经济激励政策、建立规范的回收体系、合理规划布局再生铅企业、打击违法行为等。