杨村煤与石油渣油共处理高温缩聚反应特性的研究

用ＧＪ－２型微型反应釜研究了兖州杨村煤与石油渣油在４７０℃时共处理反应的特性，结果表明，杨树煤和石油渣油在高温下进行共处理反应时，宏观表现是缩聚反应占主导地位，程序升温可提高煤的转化率，添加四氢萘到石油渣油中可抑制缩聚反应，而且添加量越大，抑制效果越明显，煤液化产物的重新加氢也会发生一定的缩聚反应，可产生微量结渣。     

煤颗粒热膨胀量与破碎特性的研究

煤颗粒的热膨胀破碎特性直接影响流化床锅炉的运行效率.本文利用热机械分析仪(TMA)测定了不同种类不同密度的型煤和原煤的热膨胀特性,并对部分破碎微观形貌进行了FSEM观察;通过旋转炉内的燃烧试验研究了热膨胀特性和破碎的关系.研究表明,煤颗粒在燃烧过程中其热膨胀破碎主要发生在挥发分析出阶段;内部挥发分的析出会使颗粒内压增大而产生膨胀,进而产生细小裂纹并破碎;挥发分越高,颗粒密度越大,其热膨胀形变率越大,越容易发生破碎现象;主要挥发分析出后热膨胀引起的破碎可以忽略.     

煤粉燃烧过程中相转变点的小波识别

相变点的识别对研究煤粉的低温共熔和结焦有重要意义.本文分别对活性炭和加入SiO2的活性炭混合物的DSC曲线求导得到的DDSC曲线进行小波分析,提取DDSC曲线的近似部分和细节部分,得到更多关于相变的定量信息,再结合其TG,DTG曲线进行分析,实现对以上两种样品燃烧过程中相变点的识别;并将该方法运用到煤粉燃烧过程的相变分析中,对相变点后的烧结形态的场发射扫描电镜分析结果表明该方法是可行的.     

煤粉再燃对600 MW锅炉NOx排放的影响

在国内某台燃用褐煤的600 MW机组锅炉上进行了煤粉再燃技术示范并进行了工业试验.机组在600 MW负荷下运行时,NOx排放可控制在274 mg/m3(烟气中氧量折算到6%,下同)的水平,比改造前下降了65.36%,同时燃烧效率没有降低.进行了常规通风、空气分级和煤粉再燃三个工况下的试验,结果表明,煤粉再燃对NOx的控制效果最好,其次为空气分级.再燃煤粉比例对NOx排放也有明显的影响,在试验条件下,随着再燃燃料比例的增加,NOx排放呈降低趋势.     

煤浆电解制氢的动力学研究

研究了煤浆电解过程中电压、温度、H₂SO₄浓度、Fe³⁺浓度等因素的影响,并进行了电解前后煤粉样品的热重测试和电解后溶液的成分分析。结果表明,电压、温度、添加的Fe³⁺浓度、H₂SO₄浓度等参数对电解过程的电流密度有较大影响。其中,温度对电流密度的影响符合阿伦尼乌斯方程,在电解电压1 V条件下煤浆电解活化能为31.87 kJ/mol。TGA和ICP分析表明,电解后煤中的部分金属离子溶入溶液,导致结构和灰分成分发生了较显著的变化。     

百叶窗浓缩器气固两相流动的试验研究

本文在以往试验基础上对百叶窗浓缩器进行了更加深入的试验研究，分析了百叶窗结构、气流等因素对浓缩器性能，即浓淡风比、阻力系数、浓缩率三个参数的影响，从而得到了优化的百叶窗结构。     

煤基腐植酸对久效磷的增效作用研究

水溶性煤基酸分为从含有水溶性煤基酸的低价煤中抽提得到的水溶性煤基酸和从不含有水溶性煤基酸的低阶煤中氧化得到的水溶性煤基酸。考察了从武川风化煤和霍林河风化褐煤通过两步催化氧化法得到的水溶性煤基酸和从晋城风化煤中得到的水溶性煤基酸对高效、高毒性的杀虫剂--久效磷生物活性的影响。结果表明：（1）三种煤基酸都能增加久效磷的生物活性；（2）所用水溶性煤基酸的理想浓度为0.0025％；（3）根据毒力曲线，久效磷、武川煤基酸-久效磷和霍林河-久效磷的致死中浓度为9.94g/ha，5.99g/ha，6.62g/ha，相对毒力系数分别为：100，165.9，150.2；（4）大田实验结果证实了水溶性煤基酸对久效磷的增效作用。     

煤沥青改质非等温动力学研究

The non-isothermal kinetics for mesophase transformation of Baogang-I coal tar pitch (I-CTP), soft pitch consisted of I-CTP and 18% phenanthrene residue oil (PRO) or I-CTP and 30% PRO have been studied in a thermal conversion unit. Kinetic parameters were calculated by using an integral method. Results showed that the process of mesophase pitch transformation could be described in first order reaction. The activation energy of I-CTP is 175.36kJ/ mol. But adding 30% PRO, which improved the reactivity of I-CTP with activation energy is 138.07kJ/mol, is not beneficial to mesophase transformation.     

Spectral analysis of rare-earth elements in ash of sapropel and its fractions

Quantitative atomic emission spectral analysis was used to study the rare-earth content in sapropel and the rare-earth distribution over the isolated fractions. The conditions for determination of Ce, Y, and La (analytical lines, arc discharge current, exposure time) were selected empirically. We calculated the metrological characteristics of the proposed technique. We have shown that in Tyurin fractionation, the nonhydrolyzable residue fraction has the highest concentrations of these elements. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 76, No. 2, pp. 273–276, March–April, 2009.     

A structural model for the time-dependent recovery of mineral suspensions

A thixotropic recovery model has been developed that is based on consideration of the microstructural interactions that occur between particles within a suspension particle network. The model is based on Smoluchowski coagulation rate theory, utilizing second order kinetics to describe the thixotropic recovery behavior. The model is applied to Na-montmorillonite-based coal tailings suspensions and is also shown to be applicable to brown coal and bauxite residue suspensions. The model describes all the recovery data well, especially at intermediate to large recovery times. The recovery of the montmorillonite suspensions at short times was faster than predicted, indicating the existence of additional factors in early-time structure development. The discrepancy may have also been due to the highly anisotropic nature of the clay platelets. The recovery rate constant, K _r , increases with increasing solids concentration (for constant surface chemical conditions) as would be expected from the basis of the model. Received: 22 September 2000 Accepted: 16 March 2001