应用无标定激光诱导击穿光谱法分析钢铁工业中氧化物材料

激光诱导击穿光谱技术是一种具有吸引力的快速定量表征材料的方法,可用于工业过程的在线监控。本文报告了该技术在多元氧化物材料分析上应用。采用激光诱导击穿光谱技术分析钢工业生产的炉渣和混合氧化物试料,然后以无标定法测定其中氧化物的浓度,结果发现,对于本研究所涉及的材料,无标定激光诱导击穿光谱方法的测定浓度值与参考值一致,大部分样品和氧化物组分的绝对误差小于2%(质量分数),大范围改变测定参数时浓度值保持稳定。研究结果表明激光诱导击穿光谱技术作为钢铁工业中新型的分析测试技术具有很大潜力。

中国工业氮氧化物排放的时空分布特征及驱动因素分析

作为"十二五"期间新纳入控制性约束指标的污染物,NO_X排放量的研究成果可为地区减排份额的制定提供依据。本文运用ESDA(探索性空间方法)分析省域工业NO_X排放的时空分布特征,进而通过LMDI模型分解探究其主要驱动因素。结果显示:1工业NO_X的排放总量虽然呈现先增加后减少的态势,但至2013年也只完成减排份额的5.6%,相对2015年15%的减排目标还有一定距离,减排形势严峻;2省域工业NOx排放在空间上呈现集聚分布特征,高排放量集聚主要出现在河北、河南、山东、江苏等中东部地区,且随时间的推移有向外围省份扩张的趋势;3LMDI模型分解结果表明,经济发展是NOx增排的主要驱动力,生产技术进步和能源利用效率提升是减排的主要控制因素,产业结构调整的减排效应在2011年后开始凸显;4以四象限图及排放量为划分依据将各省份划分为3个大类,并从改进生产技术、提高能源利用效率、增加经济鼓励、削减排放份额等方面提出相应的减排建议。

Significant contributions of the petroleum industry to volatile organic compounds and ozone pollution:Insights from year-long observations in the Yellow River Delta

The petroleum industry is a significant source of anthropogenic volatile organic compounds(VOCs),but up to now,its exact impact on urban VOCs and ozone(O_(3))remains unclear.This study conducted year-long VOC ob-servations in Dongying,China,a petroleum industrial region.The VOCs from the petroleum industry(oil and gas volatilization and petrochemical production)were identified by employing the positive matrix factorization model,and their contribution to O_(3) formation was quantitatively evaluated using an observation-based chemical box model.The observed annual average concentration of VOCs was 68.6±63.5 ppbv,with a maximum daily av-erage of 335.3 ppbv.The petroleum industry accounted for 66.5%of total VOCs,contributing 54.9%from oil and gas evaporation and 11.6%from petrochemical production.Model results indicated that VOCs from the petroleum industry contributed to 31%of net O_(3) production,with 21.3%and 34.2%contributions to HO_(2)+NO and RO_(2)+NO pathways,respectively.The larger impact on the RO_(2) pathway is primarily due to the fact that OH+VOCs ac-count for 86.9%of the primary source of RO_(2).This study highlights the critical role of controlling VOCs from the petroleum industry in urban O_(3) pollution,especially those from previously overlooked low-reactivity alkanes.

金融科技水平影响企业非CO_(2)温室气体排放的实证研究

针对企业非CO_(2)温室气体排放,以2011—2019年中国内地203个地级市面板数据为样本,构建面板门限回归模型,分析企业金融科技发展水平与非CO_(2)温室气体之间的关系.本文验证了金融科技水平影响企业非CO_(2)温室气体排放的结构特征及区域异质性影响.本研究的主要发现包括三个方面:1)金融科技的发展呈现出显著的污染减排效果,能够抑制非CO_(2)温室气体排放.企业的金融科技较低时,其工业二氧化硫减排作用较强,但更一般的情况是,在企业的金融科技水平较高时企业的工业氮氧化物减排效果大多呈现好转的态势.2)企业金融科技发展水平对企业污染减排的作用存在结构效应.金融科技覆盖广度对企业非CO_(2)温室气体的减排强度显著强于金融科技使用深度和金融数字化程度.3)金融科技对非CO_(2)温室气体减排作用存在区域差异,整体来看,中部地区显著高于东西部地区.研究结果对于各地实行差异化金融科技发展策略,推动社会经济发展全面绿色转型,实现“双碳”目标具有一定的指导价值.

Review： Perspectives on the metallic interconnects for solid oxide fuel cells

The various stages and progress in the development of interconnect materials for solid oxide fuel cells (SOFCs )over the last two decades are reviewed. The criteria for the application of materials as interconnects are highlighted. Interconnects based on lanthanum chromite ceramics demonstrate many inherent drawbacks and therefore are only useful for SOFCs operating around 1000℃. The advance in the research of anode-supported flat SOFCs facilitates the replacement of ceramic interconnects with metallic ones due to their significantly lowered working temperature. Besides, interconnects made of metals or alloys offer many advantages as compared to their ceramic counterpart. The oxidation response and thermal expansion behaviors of various prospective metallic interconnects are examined and evaluated. The minimization of contact resistance to achieve desired and reliable stack performance during their projected lifetime still remains a highly challenging issue with metallic interconnects. Inexpensive coating materials and techniques may play a key role in promoting the commercialization of SOFC stack whose interconnects are constructed of some current commercially available alloys. Alternatively, development of new metallic materials that are capable of forming stable oxide scales with sluggish growth rate and sufficient electrical conductivity is called for.

Quality of effluents from Hattar Industrial Estate

Of 6634 registered industries in Pakistan, 1228 are considered to be highly polluting. The major industries include textile, pharmaceutical, chemicals (organic and inorganic), food industries, ceramics, steel, oil mills and leather tanning which spread all over four provinces, with the larger number located in Sindh and Punjab, with smaller number in North Western Frontier Province (NWFP) and Baluchistan. Hattar Industrial Estate extending over 700 acres located in Haripur district of NWFP is a new industrial estate, which has been developed with proper planning for management of industrial effluents. The major industries located in Hattar are ghee industry, chemical (sulfuric acid, synthetic fiber) industry, textile industry and pharmaceuticals industry. These industries, although developed with proper planning are discharging their effluents in the nearby natural drains and ulti- mately collected in a big drain near Wah. The farmers in the vicinity are using these effluents for growing vegetables and cereal crops due to shortage of water. In view of this discussion, there is a dire need to determine if these effluents are hazardous for soil and plant growth. So, effluents from different industries, sewage and normal tap water samples were collected and analysed for pH, electrical conductivity (EC), total soluble salts (TSS), biological oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen, cations and anions and heavy metals. The effluents of ghee and textile industries are highly alkaline. EC and TSS loads of ghee and textile industries are also above the National Environmental Quality Standards (NEQS), Pakistan. All the effluents had residual sodium carbonates (RSCs), carbonates and bicarbonates in amounts that cannot be used for irrigation. Total toxic metals load in all the effluents is also above the limit i.e. 2.0 mg/L. Copper in effluents of textile and sewage, manganese in ghee industry effluents and iron contents in all the effluents were higher than NEQS. BOD and COD values of all the industries are also above the NEQS. On the whole, these effluents cannot be used for irrigation without proper treatment otherwise that may cause toxicity to soil, plants and animals as well add to the problems of salinity and sododicity. Similarly, these effluents cannot be used for fish farming.

Polyethoxylation and polypropoxylation reactions：Kinetics,mass transfer and industrial reactor design

Ethoxylation and propoxylation reactions are performed in the industry to produce mainly non-ionic surfactants and ethylene oxide(EO)–propylene oxide(PO) copolymers.Both the reactions occur in gas–liquid reactors by feeding gaseous EO,PO or both into the reactor containing a solution of an alkaline catalyst(KOH or Na OH).Non-ionic surfactants are produced by using liquid starters like fatty alcohols,fatty acids or alkyl-phenols,while when the scope is to prepare EO–PO copolymers the starter can be a mono-or multi-functional alcohol of low molecular weight.Both reactions are strongly exothermic,and EO and PO,in some conditions,can give place to runaway and also to explosive side reactions.Therefore,the choice of a suitable reactor is a key factor for operating in safe conditions.A correct reactor design requires:(i) the knowledge of the kinetic laws governing the rates of the occurring reactions;(ii) the role of mass and heat transfer in affecting the reaction rate;(iii) the solubility of EO and PO in the reacting mixture with the non-ideality of the reacting solutions considered;(iv) the density of the reacting mixture.All these aspects have been studied by our research group for different starters of industrial interest,and the data collected by using semibatch well stirred laboratory reactors have been employed for the simulation of industrial reactors,in particular Gas–Liquid Spray Tower Loop Reactors.

Chromate and the Environment： Removal and Utilization of Industrial Waste

Chromate and dichromate sodium as a function of oxidizer characteristics are used in several industrial areas; for example, in surface protection of coated parts of cadmium, zinc and aluminum （chromate coated treated）, corrosion inhibitors, the treatment of leather, the manufacture of pigments, etc. However, the use of such products has been questioned due to the problems of toxicity and pollution that can be caused in the environmental. The Brazilian environmental agency has established that the concentrations of chromate in water courses are less than 0.5 ppm. In order to reuse chromate （CrO42） from industrial effluent, laboratory experiments have been proposed based on chemical reduction or electrolytic processes, in order to transform these chromate ions in a final mix of oxides （in solid form）, which can then be packed and sent to the production process of sodium chromate. The results of these experiments have become useful industrially （without regard to costs） considering the environmental reuse and the life cycle of the chemical compound.

Catalytic ozonation-biological coupled processes for the treatment of industrial wastewater containing refractory chlorinated nitroaromatic compounds

A treatability study of industrial wastewater containing chlorinated nitroaromatic compounds （CNACs） by a catalytic ozonation process （COP） with a modified Mn/Co ceramic catalyst and an aerobic sequencing batch reactor （SBR） was investigated. A preliminary attempt to treat the diluted wastewater with a single SBR resulted in ineffective removal of the color, ammonia, total organic carbon （TOC） and chemical oxygen demand （COD）. Next, COP was applied as a pretreatment in order to obtain a bio-compatible wastewater for SBR treatment in a second step. The effectiveness of the COP pretreatment was assessed by evaluating wastewater biodegradability enhancement （the ratio of biology oxygen demand after 5 d （BOD5） to COD）, as well as monitoring the evolution of TOC, carbon oxidation state （COS）, average oxidation state （AOS）, color, and major pollutant concentrations with reaction time. In the COP, the catalyst preserved its catalytic properties even after 70 reuse cycles, exhibiting good durability and stability. The performance of SBR to treat COP effluent was also examined. At an organic loading rate of 2.0 kg COD/（m^3.d）, with hydraulic retention time （HRT）=10 h and temperature （30±2） ℃, the average removal efficiencies of NH3-N, COD, BOD5, TOC, and color in a coupled COP/SBR process were about 80%, 95.8%, 93.8%, 97.6% and 99.3%, respectively, with average effluent concentrations of 10 mg/L, 128 mg/L, 27.5 mg/L, 25.0 mg/L, and 20 multiples, respectively, which were all consistent with the national standards for secondary discharge of industrial wastewater into a public sewerage system （GB 8978-1996）. The results indicated that the coupling of COP with a biological process was proved to be a technically and economically effective method for treating industrial wastewater containing recalcitrant CNACs.

Experimental simulation of the relative contribution of volatile-N and char-N to NO_X formation from a low-capacity bituminous coal-fired industrial boiler

The conversion of fuel-N to NOx is the main contribution of modelling problem arising from coal combustion. This paper NOx from coal-fired industrial boilers and is the least-studied summarises the current understanding of the mechanisms that account for the formation of NOx from fuel-N during coal combustion. Further experimentation on NOx emissions during bi- tuminous coal combustion was simulated with attention focused on the contribution of char-N and votatile-N to fuel-NOx through the Coal/Char combustion method. The critical analysis of this issue allowed for the identification of uncertainties and produced well-founded conclusions. The results indicated that fuel-NOx formation was a very complex physical-chemical pro- cess involving many competing mechanisms. These mechanisms included chemical reactions, convective mass transfer, heat transfer, adsorption and desorption. The contribution of char-N in this experiment varied between 30% and 70%. There may be a slight question as to the exact identity of the main contributor to fuel-NOx, and no definitive conclusion can be made as of yet This uncertainty is because the contribution of char-N to fuel-NOx was heavily affected by the combustion conditions and the contribution of char-N increased monotonically as temperature increased. There was a critical point in the relationship between particle size, air flow, 02 concentration and the contribution of char-N. The contribution of char-N increased with the increase of particle size and air flow initially when less than the critical value, and decreased when more than thecritical value. The contribution of char-N initially decreased when the 02 concentration was increased from 10% to 15% and increased more with the further increase in 02 concentration.