Differences in physical properties and CO2 gasification reactivity between coal char and petroleum coke

This paper mainly investigated the physical properties and gasification reactivity of coal char and petroleum coke, separately at the high temperature pyrolysis (950–1400 °C) with slow heating rate and pyrolysis pressure of the atmospheric pressure and at the pressurized pyrolysis (the atmospheric pressure to 3 MPa) with rapid heating rate and the pyrolysis temperature of 950 °C. Some significant differences in those between coal chars and petroleum coke were found. The high temperature pyrolysis caused more easily the graphitization of petroleum coke than that of coal char, especially in the higher temperature range. The increasing pyrolysis temperature resulted in the decrease of surface areas of coal char and the increase of surface areas of petroleum coke. As the pyrolysis pressure was elevated from the atmospheric pressure to 3 MPa, surface areas of petroleum coke initially increased and then decreased, while those of coal chars presented an opposite tendency. The increasing pyrolysis temperature was adverse to the gasification activity of coal chars and was favorable for the gasification activity of petroleum coke. Also, the effects of the pyrolysis pressure on the gasification activity of coal char and petroleum coke were significantly different. The gasification activity of petroleum coke was obviously lower than that of coal chars, and even lower than that of the natural graphite.     

连续流动分析法测定水中硫化物的显色剂配制方法研究

针对连续流动分析法测定水中硫化物方法中显色剂N,N-二甲基-1,4苯二胺二盐酸盐保质期短的问题,研究了不同体积比盐酸或硫酸介质对延长显色剂保质期的影响,确定了延长保质期的试剂配制方法,并对该方法的适用性进行了检验.结果显示,体积比10％硫酸介质的显色剂优于盐酸介质显色剂,可以存放一周.使用此显色剂进行硫化物分析检出限为0.003 mg/L,线性范围0.000 mg/L ～2.00 mg/L,平行测定相对偏差0.0％ ～11.8％,加标回收率82.0％～102％,可以满足环境样品分析需求.     

曝气加氢氧化钙复合技术抑制底泥磷释放及对底泥微生物多样性的影响

底泥磷释放是导致水体富营养化的主要原因之一,本文通过在样泥中分别投加0、0.01和0.02 mol·L-1Ca(OH)2溶液,同时进行微臭氧曝气(0.6 g·min-1),研究了曝气加氢氧化钙复合技术抑制底泥磷释放的效果及对底泥微生物多样性的影响.结果显示,投加0.02 mol·L-1Ca(OH)2组上覆水中总磷(TP)浓度的最终值与对照组相比,抑制率达到34%;从各形态磷的角度进一步分析发现,与对照组相比,该组底泥中可溶性磷和铁磷含量分别降低了92%和60%,其最终转化为钙磷是该技术的关键.通过聚合酶链式反应-变性梯度凝胶电泳技术(PCRDGGE)研究发现,各试验组微生物相似性在65%~85%之间;Berger-Parker优势度指数、Margalef丰富度指数、Shannon多样性指数变化不明显,表明该技术不会影响底泥微生物多样性.     

表面活性剂对以污泥为铝源制得的纳米Al（OH）3性质的影响研究

以污泥碳(SC)中回收的铝酸钠为铝源,在制备Al(OH)3的过程中加入表面活性剂PEG-1000(比例在0.01%~0.6%变化),考察其对Al(OH)3表面形貌和结构的影响.研究发现,当加入PEG-1000比例较小时,其空间位阻作用抑制了粒子之间的键合作用,使得Al(OH)3的沉淀效率较高、粒子尺寸较小,也能有效地阻止颗粒的团聚,SBET可以达到340 m2·g-1以上.当PEG-1000加入比例较大时,Al3+的沉淀效率逐渐降低,所得Al(OH)3粒子的尺寸变大,Al(OH)3的SBET和孔体积逐渐变小,平均孔径变大;原因是增多的PEG-1000分子会被包进Al(OH)3的结构中,限制了PEG-1000的表面交联和吸附,使空间位阻效应变差.—CH2—振动峰的出现说明PEG-1000是通过形成化学键的方式连接在Al(OH)3的表面基团上.PEG-1000的使用对于以污泥为铝源制备分散性好、尺寸较小和SBET较大的非晶态Al(OH)3具有重要作用.     

化工生产装置活性危害评估

活性危害的评估由理论筛选,热稳定性的实验筛选,动力学参数的检测装置,紧急排放系统的设计、筛选和放大,过程设计和优化等几个部分组成.     

Upscaling heterogeneity in aquifer reactivity via exposure-time concept: forward model

Reactive properties of aquifer solid phase materials play an important role in solute fate and transport in the natural subsurface on time scales ranging from years in contaminant remediation to millennia in dynamics of aqueous geochemistry. Quantitative tools for dealing with the impact of natural heterogeneity in solid phase reactivity on solute fate and transport are limited. Here we describe the use of a structural variable to keep track of solute flux exposure to reactive surfaces. With this approach, we develop a non-reactive tracer model that is useful for determining the signature of multi-scale reactive solid heterogeneity in terms of solute flux distributions at the field scale, given realizations of three-dimensional reactive site density fields. First, a governing Eulerian equation for the non-reactive tracer model is determined by an upscaling technique in which it is found that the exposure time of solution to reactive surface areas evolves via both a macroscopic velocity and a macroscopic dispersion in the artificial dimension of exposure time. Second, we focus on the Lagrangian approach in the context of a streamtube ensemble and demonstrate the use of the distribution of solute flux over the exposure time dimension in modeling two-dimensional transport of a solute undergoing simplified linear reversible reactions, in hypothetical conditions following prior laboratory experiments. The distribution of solute flux over exposure time in a given case is a signature of the impact of heterogeneous aquifer reactivity coupled with a particular physical heterogeneity, boundary conditions, and hydraulic gradient. Rigorous application of this approach in a simulation sense is limited here to linear kinetically controlled reactions.     

Herbicide Roundup® and its main constituents cause oxidative stress and inhibit acetylcholinesterase in liver of Carassius auratus

Roundup® is a glyphosate-based herbicide containing a mixture of surfactants. This paper evaluates the toxic effects of Roundup® and its main constituents on the goldfish, Carassius auratus, after 7 days exposure. Fish were exposed to 0.16, 0.032 and 0.0064 mg/L of Roundup® [containing 41% isopropylamine salt of glyphosate (G.I.S) and 18% polyoxyethylene amine (POEA)], G.I.S, and POEA. Their livers were taken for determining reactive oxygen species (ROS), superoxide dismutase (SOD) activity, malondialdehye (MDA) content and acetylcholinesterase (AChE) activity. Hydroxyl radical (·OH) could be induced by exposing Roundup® at a rate of 43%–111%, G.I.S at 90%–124% and POEA at142%–157%. A decreased SOD activity was observed in fish exposed to G.I.S and POEA. The contents of MDA significantly increased when exposed to Roundup® at all concentrations, 0.16 mg/L G.I.S and 0.032 mg/L POEA. The exposure led to an inhibition of AChE in livers overall during the experimental periods. POEA was more toxic than Roundup® or G.I.S during this experiment. AChE and ·OH are supposed to be sensitive biomarkers of the exposure of Roundup® and its main constituents to C. auratus.     

Effect of CuO on the efficiency of sulfur capture of Ca-based compounds during coal combustion

The efficiency of sulfur capture of CaO,Ca(OH)2 and CaCO3 as well as the effect of CuO on them were studied.Resulta showed that the efficiency of sulfur capture of Ca(OH)2 is the highest among these three compounds.When CuO was used with each of CaO,Ca(OH)2 and CaCO3 at the same time,the efficiency of all of them would rise,and that of Ca(OH)2 raise most.The efficiency of sulfur capture of Ca(OH)2 with CuO is 14.4% higher than that without CuO.     

含砷废水处理工程实践

介绍了一种中小型含砷废水治理的成功工程实例 ,并介绍了石灰沉降、FeSO4 除As的有关技术参数及独特的曝气系统设计。该设计弥补了以往设计中曝气系统氧利用率不高、曝气头易结垢堵塞及曝气头损坏后维修不方便等缺限。     

What is the acceptable margin of error for the oxygen uptake method in evaluating the reactivity of organic waste?

The acceptable margin of error for the organic waste reactivity measured by the oxygen uptake method was assessed. Oxygen uptake was determined by the Dynamic Respiration Index (DRI) (mgO₂/kgVS h). The composed uncertainty (uC) of the experimental set up used for the DRI test was evaluated and the uncertainty (u) of all the components of the apparatus was evaluated. A procedure for calculating the uC of the apparatus is proposed. The components affecting the uC of the DRI to a more significant extent were the one of the oxygen mass rate and the u of the amount of VS in the sample analyzed. For a confidence level of 99.73%, the extended uC (UC) interval for a DRI = 1024 mgO₂/kgVS h was ±440 mgO₂/kgVS h, whereas for a DRI = 3489 mgO₂/kgVS h, the UC interval was ±1288 mgO₂/kgVS h. When oxygen consumption and VS content become lower than 600 mgO₂/h and 0.9 kg, respectively, the UC interval is similar to the measured DRI.