离子膜烧碱中盐泥的危害分析及控制对策

通过对离子膜烧碱企业盐泥的组分及浸出毒性进行分析,可判断盐泥不属于危险废物,其环境管理的重点在减量化和综合利用2个方面。目前中国盐泥主要的处置方式以堆存或填埋为主,大多数综合利用途径尚无法实现工业化,部分途径存在一定的环境风险。为消除盐泥带来的环境风险,从源头控制和工艺过程控制等方面提出了盐泥管理对策。     

混汞法采金地区的汞污染研究进展

混汞法是一种设备简单、操作简便且应用历史悠久的提金方法，在世界范围内得到了普遍使用，同时也导致了严重的汞污染。本文介绍了混汞法的流程以及汞的释放过程和释放因子；综述了应用混汞法提金的不同国家和地区，对由此引发的大气、水体、生物(包括人体)和土壤汞污染的研究现状，并讨论了采金地区的环境管理政策。     

采用盐泥对直接染料废水脱色处理的研究

采用氯碱工业的含镁盐泥对直接染料废水进行脱色处理.以直接大红、直接深蓝和直接黑3种直接染料水溶液作为模拟染料废水,考察了盐泥活化温度、盐泥用量等对脱色效果的影响,重点分析了吸附动力学特征,并对盐泥的循环再生利用进行了初步考察.经400℃煅烧活化的盐泥对直接大红、直接深蓝和直接黑3种直接染料均有很高的脱色效果,直接大红、直接深蓝和直接黑3种染料在盐泥吸附剂上的吸附动力学过程符合拟二级动力学方程,20 min左右时,吸附接近平衡.饱和吸附的盐泥经过煅烧后可以循环使用.研究结果为盐泥的综合利用提供了一种新途径.     

混汞法采金地区的汞污染研究进展

混汞法是一种设备简单、操作简便且应用历史悠久的提金方法 ,在世界范围内得到了普遍使用 ,同时也导致了严重的汞污染。本文介绍了混汞法的流程以及汞的释放过程和释放因子 ;综述了应用混汞法提金的不同国家和地区 ,对由此引发的大气、水体、生物 (包括人体 )和土壤汞污染的研究现状 ,并讨论了采金地区的环境管理政策     

氯碱废渣盐泥的干法表面改性与填充性能研究

为了提高盐泥粉体与有机体系的相容性,采用4种偶联剂对盐泥进行干法表面改性,考察了不同改性剂种类、用量及改性时间对改性盐泥在液体石蜡中分散性的影响,并利用傅立叶红外光谱（FTIR）研究了改性机理。结果表明每种改性剂都有一个较佳用量,钛酸酯NDZ-105、 NDZ-311和NDZ-401型的较佳液固比分别为1∶20、1∶10和1∶10,硅烷偶联剂KH-570型的较佳液固比为1∶20;而在这4种偶联剂中,NDZ-105型改性效果最好,在其较佳液固比（1∶20）下,使得改性盐泥在液体石蜡中的浊度达到1 100 NTU以上,其与有机物的亲和性得到很好的改善,其合适改性时间为球磨20 min。通过对改性与未改性盐泥的红外光谱、热重与差示扫描量热分析表明改性剂与盐泥表面发生了化学吸附。通过工业填充,得到了改性盐泥填充的聚氨酯产品,其性能达到填充CaCO₃粉体的聚氨酯性能。     

盐泥吸附剂对直接染料的平衡吸附行为和热力学性质研究

以染料废水处理用盐泥吸附剂的开发为目的,在静态吸附条件下,研究了含镁盐泥对直接大红、直接深蓝和直接黑3种直接染料的吸附行为,并对吸附过程的热力学进行了分析。结果表明,吸附平衡数据都能够较好地符合Langmuir和Freundlich吸附等温方程,但Langmuir方程能够更好地描述吸附等温线。在25～30℃范围内,3种直接染料在盐泥上的吸附是一个吸热过程,同时伴随着熵值的增加,反应的吉布斯自由能变小。吸附是物理和化学吸附并存的吸附过程,主要推动力为化学键力（化学吸附）,同时可能存在范德华力（物理吸附）,吸附焓变在74120～87332 kJ/mol之间。     

水洗法处理酮连氮法制水合肼副产废盐的工艺优化

酮连氮法制水合肼会产生大量的副产废盐,这些副产盐因其中所含杂质有机物较多而无法直接回用于离子膜电解过程。采用水洗法处理此类废盐,可基本去除废盐中的杂质有机物,使废盐能够满足电解制碱的要求。为进一步探究水洗法处理废盐过程中各因素间的影响关系,采用响应曲面法,分别建立了废盐失重率和UV₂₅₄去除率与液固质量比、水洗次数和盐温度的优化模型,优化了工艺所采用的实验条件。结果表明,液固质量比、水洗次数和盐温度3者对废盐水洗过程的影响的强弱为,水洗次数>液固质量比>盐温度。根据模型预测,最佳工艺条件为,液固质量比为5: 8、水洗次数2次、盐温度25 ℃、停留时间5 min。在最佳工艺条件下的废盐失重率和UV₂₅₄去除率分别为12.6%和97.8%,实验结果与模型预测结果基本一致。处理后的废盐可满足离子膜电解用盐标准,水洗法可有效去除废盐中的杂质有机物,响应曲面法的优化结果对实际水洗过程具有指导意义。     

汞污染载金炭间接加热-N2吹扫脱汞研究

采用间接加热-N2吹扫法,对汞污染载金炭中汞的脱除进行试验研究.主要考察了吹扫方式、焙烧温度、N2流量和处理时间对汞脱除效果的影响.结果表明,采用床层内部吹扫方式有利于载金炭中汞的脱除;在550℃、N2 1.6 m3/h·kg、吹扫3 h条件下,能够将载金炭中汞含量由13.833 g/kg降低至0.002 g/kg,汞脱除率达到99.98%以上,而炭烧损率仅1.84%.另外,进行了2种二段法脱汞试验研究:高温蒸汞-N2吹扫法和空气吹扫-N2吹扫法.结果表明,与一段法相比,前者能够大大降低N2的消耗量;而后者没有明显优势,N2用量和能耗均未能明显降低.     

双硫腙法研究废电池中汞的分布及浸出

用双硫腙法测定了几种废电池中汞的含量和分布及在不同水环境条件下,汞的浸出率,试图为废电池中各组分去汞后的回收提供理论依据。结果表明,双硫腙测定废电池中汞的方法是可靠的;汞在废电池中主要分布在锌皮（锌粉）和碳包部分;pH对汞的浸出率有较大的影响,浸出率与pH呈负相关。     

固化稳定化技术修复汞污染土壤的中试试验研究

以某化工厂内含汞污染土壤为研究对象,进行了固化稳定化技术的中试试验,研究水泥和硫化钠的药剂配比和搅拌方式对处理效果的影响。结果表明,随着水泥添加量增大,汞的浸出浓度大体降低;随着硫化钠添加量的增大,汞的浸出浓度呈现明显上升的趋势;当水泥和硫化钠联用时,浸出液中汞未检出,处理效果较好;搅拌方式对土壤中汞的处理效果影响较小。综合考虑经济成本、处理效果以及增容等因素,建议采用0.05%(质量分数,下同)工业级硫化钠+5.00%复合硅酸盐水泥P.C 32.5的药剂配比和挖机铲斗混合搅拌的方式对土壤中的汞进行固化稳定化处理。     

Influence of a chlor-alkali plant on the mercury contents of fungi

Significantly higher contents of mercury were found in fungi growing in the vicinity of a large Finnish chlor-alkali plant than in a control area. The highest concentrations (72–200 ppm dry wt) were found in $\text{Agaricus}$-species. The mercury contents in mycorrhizal fungi did not generally exceed the Finnish safety limit of 0.8 ppm.     

An activated sludge process to reduce the pollution load of a dye-industry waste

A laboratory-scale activated sludge process was developed to reduce the pollution load of a dye-industry waste, containing aniline, phenol, methyl violet and rhodamine B as its major components. The waste exerted an organic load of 5576 mg litre(-1) as the chemical oxygen demand (COD), of 896 mg litre(-1) as total organic carbon (TOC), and had a 31.5 mg litre(-1) phenol content. A microbial sludge, capable of growing on the waste, was developed from cattle dung, adapted to the waste and used as a bioinoculum for the process. This resulted in reductions of 60% in COD, 37% in TOC, and 92% in phenol content, and a decrease in optical density of the colour of the waste from an initial 0.915 to 0.360 at 580 nm. Microorganisms isolated from sludge were identified as Pseudomonas alcaligenes and P. mendocina.     

Mercury levels and liver pathology in feral fish living in the vicinity of a mercury cell chlor-alkali factory

Twenty-three barbels (Barbus graellsii), 30 bleaks (Alburnus alburnus) and 4 sediment samples were collected from four areas of the Cinca River (NE Spain), upstream and downstream of a mercury cell chlor-alkali plant. Mercury concentration in sediments downstream of the plant was about 25 times higher than the concentration upstream. Mercury levels in the muscle and liver of barbels downstream of the chlor-alkali plant were 10 and 30 times higher than those upstream. The average mercury concentration in the muscle and liver of barbels downstream of the factory was 1.48 and 1.78mg/kgw.w., with maximal concentrations of 2.43 and 3.64mg/kgw.w, respectively. Liver/muscle ratio of mercury was significantly higher in barbels sampled downstream of the factory. Bleak showed a similar pattern, with a significantly higher whole-body mercury concentration downstream of the chlor-alkali plant. Nevertheless, a progressive decrease in mercury concentration downstream of the impact area was found in bleak, but not in barbel. Histopathological analysis showed that fish downstream of the factory had significantly higher prevalence of liver pathologies (p<0.05). Although there are no specific histopathological markers of mercury exposure, barbels with the highest Hg levels in the liver also showed the most severe pathologies, and the processes found in these barbels were consistent with the pro-oxidant effect of heavy metals.     

宁波地区海产品中汞污染现状研究

采用冷原子吸收（荧光）法测定了宁波不同地区的各种海产品中总汞和甲基汞含量，总体属轻度及中等污染水平，工业轻发达地区的海产品内总汞和甲基汞的含量较高，不同种类海产品因食性不同，在食物链中所处位置不同，表现为贝壳类＞肉食性类＞杂食性类＞植食性类＞藻类和水草，无鳞鱼类＞有鳞鱼类；海产品中不同部分污染水平表现为内脏＞头部＞肌肉；海水＜底泥＜海产品。除个别样品接近国家标准外，其余都符合我国食品卫生标准。     

Measurement of total site mercury emissions from a chlor-alkali plant using ultraviolet differential optical absorption spectroscopy and cell room roof-vent monitoring

This technical note describes a United States Environmental Protection Agency (U.S. EPA) measurement project to determine elemental mercury (Hg⁰) emissions from a mercury cell chlor-alkali (MCCA) facility in the southeastern U.S. during a 53-day monitoring campaign in the fall of 2006. The optical remote sensing (ORS) area source measurement method EPA OTM 10 was used to provide Hg⁰ flux data for the site. These results are reported and compared with cell room roof-vent monitoring data acquired by the facility for similar time periods. The 24-h extrapolated mercury emission rate estimates determined by the two monitoring approaches are shown to be similar with overall averages in the 400 g day^?1 range with maximum values around 1200 g day^?1. Results from the OTM 10 measurements, which include both cell room emissions and potential fugitive sources outside the cell room, are shown to be approximately 10% higher than cell room monitoring results indicating that fugitive emissions from outside the cell room produce a small but measurable effect for this site.     

活性污泥二次污染问题的探讨(Ⅱ)

讨论了城市污水经过A／O工艺处理时活性污泥的二次污染问题。将原水、处理后的出水及活性污泥用甲苯萃取，萃取相经过真空浓缩后，采用GC／MS测定了样品中的有机化合物，结果表明，在A／O工艺处理城市污水过程中，活性污泥的吸附作用是主要的，降解作用是次要的；A／O工艺所排放的活性污泥仍然是一种危险的污染物。     

Development of a regenerable system employing silica-titania composites for the recovery of mercury from end-box exhaust at a chlor-alkali facility

The release of mercury to the environment is of particular concern because of its volatility, persistence, and tendency to bioaccumulate. The recovery of mercury from end-box exhaust at chlor-alkali facilities is important to prevent release into the environment and reduce emissions as required by NESHAP (National Emission Standards for Hazardous Air Pollutants). A pilot-scale photocatalytic reactor packed with silica-titania composite (STC) pellets was tested at a chloralkali facility over a 3-month period. This pilot reactor treated up to 10 ft3/min (ACFM) of end-box exhaust and achieved 95% removal. The pilot reactor was able to maintain excellent removal efficiency even with large fluctuations in influent mercury concentration (400-1600 microg/ft3). The STC pellets were regenerated ex situ by regeneration with hydrochloric acid and performed similarly to virgin STC pellets when returned to service. On the basis of these promising results, two full-scale reactors with in situ regeneration capabilities were installed and operated. After optimization, these reactors performed similarly to the pilot reactor. A cost analysis was performed comparing the treatment costs (i.e., cost per pound of mercury removed) for sulfur-impregnated activated carbon and the STC system. The STC proved to be both technologically and economically feasible for this installation.