加油站油气回收系统分析与关键技术研究

深入分析了加油站平衡式油气回收系统、真空泵辅助式油气回收系统的美国模式和德国模式的油气回收效率和关键技术问题,揭示了密封性是平衡式失败和美国模式低效的根本原因,解决了困扰业界的罐压不高、罐压保持、后处理装置是否必要等困惑和争议,提出高效率、低密封性要求的"低罐压真空泵辅助式油气回收系统"技术方案和实施方案。     

硫酸系统水平衡分析计算和生产实践

在硫酸系统中,通过水平衡分析计算烟气带入净化工序的SO2体积分数和含水量,确定净化工序的能力,控制干燥塔进口烟气温度,使干吸工序生产出合格产品;通过计算,烟气带入净化工序的水量小于产品带出的水量,制酸净化污水经过污水处理工序处理后返回到净化工序重复使用,实现净化污水零排放,消除对环境的污染.     

低温水解酸化-A~2/O（PACT）-混凝沉淀处理印染废水

低温条件下对水解酸化-A2/O（PACT）-混凝沉淀组合工艺处理印染废水进行了中试研究。考察印染废水中COD和色度去除效果,结果表明：低温对工艺负面影响较大,未加粉末活性炭时好氧段COD和色度的去除率分别为42.6%和58.9%;投加粉末活性炭后,去除率分别达55.8%和65.4%,提高了13.2%和6.5%,显示出低...     

Transport and fate of mercury under different hydrologic regimes in polluted stream in mining area

Seepage from Hg mine wastes and calcines contains high concentrations of mercury (Hg). Hg pollution is a major environmental problem in areas with abandoned mercury mines and retorting units. This study evaluates factors, especially the hydrological and sedimentary variables, governing temporal and spatial variation in levels and state of mercury in streams impacted by Hg contaminated runo . Samples were taken during di erent flow regimes in theWanshan Hg mining area in Guizhou Province, China. In its headwaters the sampled streams/rivers pass by several mine wastes and calcines with high concentration of Hg. Seepage causes serious Hg contamination to the downstream area. Concentrations of Hg in water samples showed significant seasonal variations. Periods of higher flow showed high concentrations of total Hg (THg) in water due to more particles being re-suspended and transported. The concentrations of major anions (e.g., Cl??, F??, NO3?? and SO4 2??) were lower during higher flow due to dilution. Due to both sedimentation of particles and dilution from tributaries the concentration of THg decreased from 2100 ng/L to background levels (< 50 ng/L) within 10 km distance downstream. Sedimentation is the main reason for the fast decrease of the concentration, it accounts for 69% and 60% for higher flow and lower flow regimes respectively in the upper part of the stream. Speciation calculation of the dissolved Hg fraction (DHg) (using Visual MINTEQ) showed that Hg(OH)2 associated with dissolved organic matter is the main form of Hg in dissolved phase in surface waters in Wanshan (over 95%).     

Antimicrobial activity of thin metallic silver flakes, waste products of a manufacturing process

The aim of the research was to develop new products and processes from a manufacturing waste from an Italian metallurgic company. The company produced thin silver metallic films and the production scraps were silver flakes. The possibility to use the silver flakes in water disinfection processes was studied. The antimicrobial activity of the flakes was investigated in batch using Escherichia coli as Gram-negative microorganism model. The flakes did not show any antimicrobial activity, so they were activated with two different processes: thermal activation in reducing atmosphere and chemical activation, obtaining, respectively, reduced flakes (RF) and chemical flakes (CF). The flakes, activated with either treatment, showed antimicrobial activity against E. coli. The kill rate was dependent on the type of activated flakes. The chemical flakes were more efficient than reduced flakes. The kill rate determined for 1 g of CF, 1.0 ± 0.2 min⁻¹, was greater than the kill rate determined for 1 g of RF, 0.069 ± 0.004 min⁻¹. This was confirmed also by the minimum inhibitory concentration values. It was demonstrated that the antimicrobial capability was dependent on flakes amount and on the type of aqueous medium. Furthermore, the flakes maintained their properties also when used a second time. Finally, the antimicrobial activities of flakes were tested in an effluent of a wastewater treatment plant where a variety of heterotrophic bacteria were present.     

Evaluation of adsorption capacities of humic acids extracted from Algerian soil on polyaniline for application to remove pollutants such as Cd(Ⅱ), Zn(Ⅱ) and Ni(Ⅱ) and characterization with cavity microelectrode

The adsorption capacities of new humic acids isolated from Yakouren forest (YHA) and Sahara (Tamenrasset: THA) soils (Algeria) and commercial humic acid (PFHA) on polyaniline emeraldine base (PEB) were studied at pH 6.6. Also the adsorption of heavy metals such as Cd2+, Zn2+ and Ni2+ on humic acid-polyaniline systems (HA-PEB) was investigated at the same conditions. HA-PEB compounds were characterized by scanning electron microscopy (SEM), infrared spectrometry and cavity microelectrode. In addition, batch adsorption and cavity microelectrode were used in the adsorption study of Cd2+, Zn2+ and Ni2+ on HA-PEB. To develop biocaptors of polluting metals using a cavity microelectrode modified by HA-PEB systems, the adsorption kinetic and adsorption capacity were investigated. The SEM analysis showed that the presence of humic acid affected the PEB surface and caused the formation of a granular morphology. The maximum adsorption capacities (qmax) of PFHA, THA and YHA determined by adsorption isotherms were 91.31, 132.1 and 151.0 mg/g, respectively. Batch adsorption results showed that qmax of Cd2+, Zn2+ and Ni2+ on HA-PEB followed the order: THA-PEB > YHA-PEB > PFHA-PEB. The voltammograms obtained with HA-PEB modified cavity microelectrode showed the appearance of new redox couples reflecting the adsorption of HA on PEB. Metal-humic acid-polyaniline voltammograms were characterized by appearance of oxidation-reduction couples or reduction wave corresponding to metal. Finally, the result may be exploited to develop a biocaptor based on the cavity microelectrode amended by THA-PEB and YHA-PEB.     

中心组合设计优化S-Cr-TiO2催化剂光降解工艺条件

在确定的温度和光照条件下,采用中心组合设计法研究了固相反应法合成的硫与铬共掺杂二氧化钛(S-Cr-TiO2)光催化剂与水溶苯胺蓝(ANB)可见光降解过程中的三个作用因子:催化剂的浓度、水溶苯胺蓝水溶液的pH值及其初始浓度之间的相互作用关系,得到了影响因子与降解速率之间的回归方程及因素之间相互作用的响应面图.结果表明,S...     

吹扫捕集-气相色谱法测定水中的乙醛和丙烯醛

建立了吹扫捕集-气相色谱法测定水样中乙醛和丙烯醛的方法,并对吹扫捕集测试条件进行优化,考察了吹扫温度和吹扫时间对吹扫捕集效率和方法检出限的影响。在50℃下,吹扫时间为20 min时,该方法乙醛和丙烯醛的检出限分别为0.001 2 mg/L、0.000 6 mg/L,相对标准偏差分别为3.5%～6.9%、2.9%～5.8%,加标回收率分别为91.6%～108%、92.0%～105%。与GB3838-2002推荐使用的分析方法相比较,该方法具有操作简便、灵敏度高、重复性好、基本上不消耗有机溶剂等特点,可满足地表水和废水中乙醛和丙烯醛的测定要求。     

大型炼化一体化项目清洁生产评价实例研究

炼化一体化、装置大型化为炼油项目的发展趋势,符合清洁生产、循环经济原则。目前炼化一体化项目尚无相应的清洁生产标准。综合指标评价法将定性指标量化与定量指标统一起来,从而能从整体上做出一个明确的判断结果。以国内同行业先进企业各项指标为基准值,对某1000万t/a炼油、100万t/a乙烯一体化项目实例研究表明,采用综合指标评价法进行清洁生产评价,使得定性分析和定量评价结果得到了较好的吻合,评价结果更具科学性与实用性。综合指标评价法不仅可以用于大型炼化一体化项目环境影响评价时的清洁生产评价,也可用于现有工程的清洁生产审核以及企业实施清洁生产绩效评价。     

不同进水条件对SBR工艺脱氮除磷效能的影响

采用人工配水,研究进水在不同pH值,碳源类型,碳氮比条件下,厌氧/好氧/缺氧(A/O/A)sBR工艺对生物法脱氮除磷效能的影响.结果表明:不同的进水条件对反应器的影响较大,当pH值为7.5,乙酸钠为碳源,碳氮比为1.4时,反应器运行效果最佳,系统对PO43--P,NH4+-N的去除率分别达到97.28%,99.5%.N...