O2/CO2气氛下循环流化床煤燃烧SO2排放

在热输入功率50 kW的循环流化床O₂/CO₂燃烧试验装置上研究燃煤SO₂排放特性及石灰石脱硫机理。结果发现,未添加石灰石时,O₂/CO₂气氛下SO₂排放量比相同O₂浓度的空气气氛下低;随着O₂浓度的升高,排放量升高。相同钙硫摩尔比下,O₂/CO₂气氛下石灰石的脱硫机理以直接脱硫为主,脱硫效率比空气气氛下高;随着O₂浓度的增加,石灰石脱硫效率提高。     

氧化铁促进石灰中温烟气脱硫的机理性研究

本文运用热重分析仪和扫描电镜（ＳＥＭ）对石灰与氧化铁混合物进行了测定，分析了在２００～７００℃的中温范围内氧化铁对石灰脱硫过程的促进作用．研究表明；在石灰中掺入一定比例的氧化铁可以显著捉高钙利用率，而且存在最佳氧化铁配比．其作用机理是氧化铁对石灰脱硫不仅具有一定的催化作用，同时还作为活性中心 改变了脱硫产物的形成规律和气体扩散等特性．     

NH_3多相氧化的实验研究

1引言煤燃烧过程中特别是流化床中为了减少SOZ的排放，一般采用向炉内加入石灰石等添加物的方法。这些添加物质的存在，使挥发分含氮物质的氧化机理异于纯单相氧化。因此研究钙基脱硫剂（CaCO。）及其生成物（CaSO。、煤灰）对NH。和HCN的多相氧化有助于了解实际锅炉煤燃烧过程中脱硫对氮氧化物生成的影响。Lin［‘］研究了石灰石和CaSO。对NH。氧化的影响。发现石灰石对NH。氧化生成NO具有相当大的催化作用，可使NH3MNO的转化率达65％，而C3SO4存在和空管时NH3氧化结果一致，表明CaSO。对NHa无氧化作用。IisJ‘」在研究Ca…     

炉内喷钙脱硫过程数值模拟

建立了一套较为完整的对炉内喷钙脱硫过程进行模拟的方法，获得了炉内气固两相流动、温度分布、石灰石颗粒脱硫化学反应和SO2浓度分布的详细情况。石灰石颗粒的硫化反应主要发生在颗粒与烟气均匀混合之前。     

生石灰颗粒中温脱硫过程数值计算

本文采用晶粒模型对中温条件下单颗粒石灰石脱硫过程进行数值模拟。利用已有文献数据、电子显微镜及TGA实验数据确定模型中化学反应动力学以及物性参数。计算结果与TGA实验结果符合较好,表明脱硫模型可直接应用于中温条件下石灰石脱硫过程的数值预报与分析。     

城市固体废物(MSW)热解特性及其动力学研究

利用热重-差热分析仪对城市固体废物（MSW）中厨余物、废纸、废塑料、废木料和废织物等典型有机组份进行了热分析研究。试验载气为高纯氮气．加热速率为10K／min．终温为773K。通过对热重（TG）、差热（DTA）和微分热重（DTG）曲线的深入分析,得出了MSW中几种典型有机组份的热解反应动力学参数,并提出了相应的热解机理。     

高温快速退火对重掺锑硅单晶中流动图形缺陷的影响

对大直径重掺锑硅单晶中流动图形缺陷（FPDs）进行了研究.利用高温快速退火工艺（RTA） ，将重掺锑硅片在N₂，Ar，H₂三种不同气氛下进行热处理，对退 火前后FPDs的密度变化进行了研究，分析了重掺锑硅单晶中FPDs在不同高温RTA过程中的热 稳定性.并从重掺杂原子锑与间隙氧之间的关系，分析了重掺锑硅片中FPDs在高温快速退火 工艺下的消除机制，认为重掺锑硅单晶中大量的锑原子，影响了硅片中间隙氧的浓度分布， 进而影响了原生微缺陷的形成及热行为. 关键词： 重掺锑硅单晶 快速退火（RTA） 流动图形缺陷（FPDs） 空洞缺陷     

石灰石闪蒸改性及脱硫性能的试验研究

本文对3种不同产地的石灰石进行了闪蒸改性处理,对改性石灰石颗粒的孔径分布进行了测定,研究了压力、温度等参数对石灰石闪蒸改性的影响。并在气流反应器上对闪蒸后的样品进行了硫化试验。结果表明,在一定的压力和温度下,闪蒸处理能够增大石灰石颗粒的微孔孔径,并使石灰石样品的脱硫性能得到较大提高。     

一种半干法烟气脱硫灰利用的新工艺

半干法烟气脱硫灰所含的大量亚硫酸钙导致脱硫灰处置和利用困难,制约了半干法烟气脱硫技术的推广.本文提出一种半干法烟气脱硫灰热分解制取高浓度二氧化硫联产氧化钙的的新方法.通过文献调研结合某电厂脱硫灰的热重特性,确定本工艺中关键反应的特征温度.针对新工艺的技术难点提出解决方案即采用高温固体热载体作为脱硫灰分解热源,脱硫灰两级...     

热红联用技术在森林火灾烟气测试中的应用

探索了一套基于热重分析仪-红外光谱分析仪联用（热红联用）技术的森林火灾烟气测试方法.该方法在对森林可燃物燃烧的热失重过程进行热重分析的同时,同步地对热解气体成分进行傅里叶红外光谱（FTIR）分析,从而实现了对燃烧过程诸因素的跟踪分析.     

Na2CO3调质钙基脱硫剂硫化机理实验研究

对经Na2CO3溶液调质石灰石煅烧产物CaO的物理结构及硫化特性进行了研究,发现同等条件下调质后石灰石煅烧产物CaO(M-CaO)比未经调质的CaO(N-CaO)具有更高的钙转化率.利用XRD技术对CaO晶体结构进行了测定,通过比较二者的晶胞参数和晶格畸变度等并结合其孔特性,证实M-CaO之所以比N-CaO具有更高的钙转化率,是由于M-CaO比N-CaO具有更高的晶体缺陷浓度,使得在硫化反应过程中通过产物层的扩散具有更高的离子扩散率.     

Investigation of the pore blockage of a Brazilian dolomite during the sulfation reaction

The influence of the temperature and reaction time on the sulfation process of a dolomite is investigated in this paper. The sulfation effectiveness was evaluated and correlated with changes in the physical characteristics of a Brazilian dolomite during the reactive process. Calcination and sulfation experiments were performed under isothermal conditions for dolomite samples with average particle sizes of 545 μm at temperatures of 750 °C, 850 °C and 950 °C at different times of sulfation. Thermogravimetric tests were applied to establish the reactivity variation of the dolomite in function of the time in the sulfation reaction and evaluate the methodology of the samples preparation. Porosimetry tests were performed to study the pore blockage of dolomite during the sulfation reaction. The highest values of BET surface area were 25.55 m²/g, 29.55 m²/g and 12.62 m²/g for calcined samples and after their sulfation processes, conversions of 51.5%, 61.9% and 42.8% were obtained at 750 °C, 850 °C and 950 °C, respectively. Considering the process as a whole, the best fit was provided by a first-order exponential decay equation. Moreover, the results have shown that it is possible to quantify the decreasing in the dolomite reactivity for sulfur dioxide sorption and understand the changes in the behavior of the sulfation process of limestones when applied to technologies, as fluidized bed combustor, in which sulfur dioxide is present.     

亚甲蓝与硫酸化茯苓多糖相互作用机理的研究

为从分子水平认识硫酸化多糖分子与小分子之间相互作用的机理,文章采用氯磺酸-吡啶法(Wolfrom法)对茯苓多糖进行结构修饰,制得硫酸化茯苓多糖(SP)。通过理论模型测得亚甲蓝(MB)与SP最大结合数N=54,结合常数K=1.563×106,考察了反应体系中MB/SP摩尔比、NaCl、乙醇、羟丙基-β-环糊精以及Triton X-100对相互作用的影响。探讨了MB与SP相互作用产生变色反应的机理,认为其是在MB 与SP大分子间发生静电相互作用的基础上,结合态MB分子之间的疏水相互作用所引起的。     

Alkali sulfation during combustion of coal in a pilot scale facility using additives to alter the global sulfur to potassium and chlorine to potassium ratios

Due to the urgent needs to reduce anthropogenic carbon dioxide emissions there is an increasing interest in the use of alternative fuels. For this reason, there is a need for new knowledge on how to design and adapt existing heat and power plants to biogenic and waste-derived fuels. This work relates to co-firing of biomass and coal and the sulfation of alkali chlorides in coal-fired flames doped with chemical additives. We aim to examine the global time scales of alkali sulfation and chlorination based on combustion experiments that were conducted in a 30-kW coal flame. Temperature, gas and particle composition measurements were conducted. Both experiments and modelling support that the apparent alkali sulfation kinetics are fast in a coal-fired flame and that it is dominated entirely by the presence of SO₂. The availability of oxygen and carbon monoxide, or hydrocarbons, is also critical to sustain the sulfation reaction cycle; low concentrations are sufficient. For industrial boilers this implies that sulfur addition, in combination with reburning, should constitute an efficient strategy to mitigate alkali-chlorination and the related high temperature corrosion.     

Affinity of protein fibres towards sulfation

Wool, Bombyx mori and Antheraea pernyi (Tussah) silk fibres were treated with chlorosulfonic acid in pyridine and investigated by FT‐IR and FT‐Raman spectroscopies as well as mechanical measurements. The reactivity towards sulfation was found to decrease along the series: wool > Bombyx mori silk fibroin > Tussah silk fibroin, in agreement with weight gain which decreased along the same series. Accordingly, Tussah silk maintained its intrinsic tensile properties essentially unchanged upon the treatment, while for Bombyx mori silk fibroin, the tensile performance decreased sharply especially at longer reaction times. Sulfated wool was characterized by an increased fibre extensibility. New IR and Raman bands attributable to various vibrations of sulfated groups were detected in sulfated wool and to a lower extent in Bombyx mori silk fibroin fibres; all the fibres underwent conformational rearrangements upon sulfation, independent of the sulfation yield. Wool fibres treated with chlorosulfonic acid in pyridine bound considerable amounts of sulfate mainly through the hydroxyl groups of serine, threonine and tyrosine. Also, tryptophan and basic amino acids were found to participate to the reaction. B. mori silk fibroin fibres appeared to bind a minor amount of sulfate groups mainly trough the hydroxyl groups of Ser. Weight gain, spectroscopic and mechanical data are discussed in relation to the difference in fibre morphology, structure and crystallinity, as well as to the amount and accessibility of potentially reactive amino acids. Copyright © 2012 John Wiley & Sons, Ltd.     

高CO2浓度下钙基吸收剂脱硫的实验研究

本文进行了高CO2浓度下钙基吸收剂脱硫的实验研究.结果表明,高浓度CO2下钙基吸收剂的脱硫效率随脱硫时间的变化与空气条件下显著不同.孔隙结构分析及热重分析等手段表明高CO2浓度主要影响了钙基吸收剂的煅烧分解过程,形成了有利于脱硫反应的孔隙结构.实验结果还表明提高温度有利于改善高浓度CO2气氛下钙基吸收剂煅烧后孔隙结构,在适当的脱硫时间内,高温下高浓度CO2气氛比空气气氛更有利于炉内喷钙脱硫.     

Quantitative K-Cl-S chemistry in thermochemical conversion processes using in situ optical diagnostics

The sulfation of gas-phase KOH and KCl was investigated in both oxidizing and reducing atmospheres at temperatures of 1120 K, 1260 K, 1390 K, and 1550 K. Well-defined gas environments were generated in a laminar flame burner fuelled with CH₄/air/O₂/N₂. Atomized K₂CO₃ and KCl water solution fog and SO₂ were introduced into the hot gas as sources of potassium, chlorine, and sulfur, respectively. The in situ concentrations of KOH, KCl, and OH radicals were measured using broadband UV absorption spectroscopy, and the concentration of K atom was measured using TDLAS at 769.9 nm and 404.4 nm. The nucleated and condensed K₂SO₄ aerosols were visualized as illuminated by a green laser sheet. With SO₂ addition, reduced concentrations of KOH, KCl, and K atom were measured in the hot gas. The sulfation was more significant for the low temperature cases. KOH was sulfated more rapidly than KCl. K₂SO₄ aerosols, formed by homogeneous nucleation, were observed at temperatures below 1260 K. At 1390 K, no aerosols were formed, indicating that the consumed KOH was transformed into gaseous KHSO₄ or K₂SO₄. K atoms formed in the hot flue gas with KOH addition enhanced the consumption of OH radicals except at the high-temperature case at 1550 K. At 1120 K and 1260 K, the sulfation of KOH with SO₂ seeding reduced the concentration of K atom, resulting in less OH radical consumption. Studies were also conducted in a hot reducing environment at 1140 K, with the flame at an equivalence ratio of 1.31. Similar to the observation in the oxidizing atmosphere, the concentrations of KOH and K atom decreased dramatically with SO₂ seeding. An unknown absorption spectrum observed was attributed to UV absorption by KOSO. The experimental results were used to evaluate a detailed K-Cl-S reaction mechanism, and a reasonable agreement was obtained.     

Preparation and Acid Catalytic Activity of TiO2 Grafted Silica MCM-41 with Sulfate Treatment

采用连续嫁接方法对纯硅MCM-41孔道表面分别进行一次和两次TiO2修饰,并进行了硫酸根促进,制备了具有规整介孔结构的硫酸根促进型复合金属氧化物ST/MCM-41和d-ST/MCM-41;同时制备了经一次钛修饰但未经硫酸根促进的样品T/MCM-41作为对比. 利用XRD、氮吸附-脱附、元素分析、拉曼光谱和红外光谱等表征手段,对所制样品的结构和表面酸性进行考察;利用假性紫罗兰酮环化这一典型的酸催化反应对其催化活性进行评价,并与工业应用的大孔磺酸树脂Amberlyst-15进行催化性能比较. 表征结果显示,纯     

Unifying effectors of circadian rhythm: Protein N-acetylation,phosphorylation, sulfation and other electrical effects

The vast literature concerning circadian rhythm is devoted mostly to forces that influence operation and harmful effects resulting from disturbances to the clock. The present review presents a novel, unifying theme for influences from protein N-acetylation, phosphorylation and sulfation based on electrochemistry. The unifying theme entails formation of electrostatic fields in the various processes, namely from formation of amide from protein amine in acetylation, presence of phosphate anions from phosphorylation and sulfate anions from sulfation. The electrostatic fields may operate as bridges in communication or in energetics derived from phosphorylation. Other electrochemical and magnetic effects are presented.