混煤质量评价方法的研究与应用

建立在传统的单种煤基础上的配煤炼焦理论难以适应现代煤源状况,必须依据中国煤炭分类的原则和商品煤反射率分布图来确定炼焦煤的黏结性和结焦性,鉴别其混煤的程度,正确评价混煤的性质及其在炼焦配煤中的作用,通过小焦炉炼焦,制定合适的配煤方案。试验表明,合理利用混煤配煤炼焦,可以消除混煤对炼焦配煤的不利因素,生产出高质量的焦炭,满足高炉生产的要求。     

微强黏比配煤参数的应用研究

为了评价混煤等因素造成单种煤质量差异较大的问题,应用煤岩学观点提出了微强黏比的概念。微强黏比从微观角度反映了炼焦配煤最为关注的强黏结煤比例,为传统单种煤评价方法提供了有益的补充。同时该指标与焦炭反应性和反应后强度之间有着良好的相关关系,可作为影响焦炭质量的关键参数指导炼焦配煤生产。     

卡尔曼滤波在混煤鉴定中的应用

对宝山钢铁公司４种生产用单种煤配制成的１１种混煤进行了滤波计算，尝试了一种计算机模式识别技术－卡尔曼滤波在混煤鉴定中应用的可能性。     

煤岩分析在配煤炼焦中的应用

介绍了煤岩分析在进厂原料煤的分类、混煤辨别、优化配煤方案以及和用单种煤反射率分布图合成配合煤反射率分布直方图来预测焦炭质量等方面的应用,用于指导配煤炼焦生产,取得了明显的效果。     

混煤的流化床热解动力学研究

采用微型流化床热分析仪(MFBRA),探讨了不同煤种及其混煤在相同的热解条件下甲烷的析出特征及其生成动力学.结果表明,在相同的热解条件下,煤热解过程中甲烷的开始析出温度随煤中挥发分的升高而降低,甲烷的最大析出速率及甲烷的生成总量都随煤中挥发分的升高而增加;煤热解反应的活化能(E)随煤中挥发分的升高而降低,表示煤的挥发分愈高,煤的热解愈容易进行;配煤改变了单种煤的煤质特征,其水分、挥发分和灰分等煤质指标等于单种煤相应煤质指标的加权平均值,但混煤热解的活化能(E)并不等于配合单种煤活化能(E)的加权平均值.     

主焦煤配入比例对焦炭热反应性的影响

在40kg焦炉上进行了多方案的配煤炼焦试验,并对单种煤及配合煤炼焦的焦炭热反应性进行了分析,结果表明,单种焦煤炼焦时25JM的反应后强度最好;配合煤中控制主焦煤的配入比例,适当配入14SM、1／2ZN或26FM后,焦炭的热反应性比单种焦煤炼焦的效果好。     

炼焦煤混煤特性对配煤炼焦的影响

针对炼焦煤混煤严重造成单种煤质量差异较大的问题,应用煤岩学观点从混煤的角度,探讨了混煤特性对配煤炼焦质量的影响。试验结果显示国内炼焦煤有2/3以上属于混煤,混煤是造成焦炭质量波动的主要原因。按国标以反射率方差S₀来表征混煤特性,其对炼焦煤的粘结性能有一定影响,对焦炭的冷热强度无明显的影响趋势。以微强粘比WQN作为混煤特性指标,对炼焦煤的粘结性影响较小,而对焦炭冷强度M40和焦炭热强度CSR有明显的影响趋势。     

煤的岩相分析在配煤炼焦中的应用

煤岩分析法已成为辨别煤质特别是确认混煤情况的重要手段,它在某些方面弥补了工业分析在检验煤质上的一些不足。文中依据镜质组反射率具有加和性的特点,利用单种煤反射率分布图合成配合煤反射率分布图指导炼焦配煤,可以使焦炭质量达到最优。     

热改质低阶烟煤对配煤及型煤炼焦影响研究

为了提高低阶煤在配煤炼焦中的配入比例,以低灰低硫低阶烟煤为原料,通过热改性预处理工艺得到提质改性煤。将低阶煤与改性煤按照不同比例混合成炼焦用煤,通过5 kg焦炉试验,研究了改质低阶煤对配煤及炼焦的影响。结果表明,在保证焦炭质量的前提下,低阶烟煤配入比例由小于3%提高到5%,5%以后焦炭质量明显劣化;改性煤添加比例为6%时,混煤黏结性最好,反应后强度增加约4%,而冷态强度变化不大。采用型煤技术可使改性煤配入量达到7%~10%,由于提高了混煤的密度,使炭化过程中半焦化阶段的收缩降低而使焦炭裂纹减少,煤中黏结组分和惰性组分的胶结作用得到改善,提高了煤的结焦性能。     

SYSTEM-6称重仪在配煤系统的应用

中吕焦化公司年产焦炭60万t,进厂煤种、煤质变化比较频繁,为改善和稳定焦炭质量,我们将单种煤配人的比例进行细化,在实际执行过程中根据不同煤质对单种煤配量进行有效控制。     

生物质和煤共热解特性及催化剂对热解的影响

为研究生物质和煤程序升温共热解特性及相互作用,利用热天平和管式炉反应器对白松木屑和五彩湾烟煤的共热解特性及催化剂对生物质和煤共热解的影响进行了研究,并考察了共热解半焦的孔结构特性。结果表明：不同比例的生物质和煤在共热解过程中,两者基本保持了各自的热解特性,由于生物质和煤的主要热解阶段温度相差较大,共热解过程中没有发生明显的协同作用。生物质和煤共热解半焦产率实验值大于计算值,当生物质质量分数从75%减少至25%时,半焦产率实验值与计算值之间的差值从0.81个百分点增加到1.07个百分点。橄榄石和载镍橄榄石（NiO/olivine）的添加促进了共热解反应发生的深度。载镍橄榄石催化剂添加（原料和催化剂质量比1：1）的条件下,共热解碳转化率提高了0.5%~5.1%,随着混合物中生物质比例的增加,催化剂的催化效果更加明显。     

Assessment of petrographic model for the prediction of coke strength

The strength of coke produced from Mongolian coal is calculated within the framework of Eremin’s petrographic model, on the basis of literature data from a maceral analysis of such coal. The model produces quantitatively correct values of the strength characteristics M ₂₅ and M ₁₀. The clinkering microstrength of coal grains for individual ranks and the postreactive strength CSR of the coke may also be estimated.     

Enhancement of combustion efficiency with mixing ratio during fluidized bed combustion of anthracite and bituminous blended coal

In order to investigate the effect of mixing ratio of bituminous coal to blended coal on the enhancement of combustion efficiency, combustion experiments of blended coal with anthracite and bituminous are done in a laboratory scale fluidized bed combustor (10.8 cm ID and 170 cm height). The gross heating values of anthracite and bituminous coal used in this study are 2,810 cal/g and 6,572 cal/g, respectively. Experimental parameters are fuel feed rate, superficial gas velocity and mixing ratio of bituminous coal to blended coal. The combustion efficiency increases with the mixing ratio of bituminous coal due to the lower unburned carbon losses and higher burning velocity of bituminous coal. The rate of combustion in the combustor was increased with mixing ratio resulted from a higher burning velocity of bituminous coal. The measured combustion efficiency experimentally is about 3.5-12.4% higher than that of the calculated value based on the individual combustion of anthracite and bituminous coal under the same operating conditions. The optimum mixing ratio (MR) of bituminous coal determined is around 0.75 in this study. This paper is dedicated to Professor Dong Sup Doh on the occasion of his retirement from Korea University.     

Co-pyrolysis of bituminous coal and biomass in a pressured fluidized bed

An experimental study on co-pyrolysis of bituminous coal and biomass was performed in a pressured fluidized bed reactor. The blend ratio of biomass in the mixture was varied between 0 and 100 wt%, and the temperature was over a range of 550–650 °C under 1.0 MPa pressure with different atmospheres. On the basis of the individual pyrolysis behavior of bituminous coal and biomass, the influences of the biomass blending ratio, temperature, pressure and atmosphere on the product distribution were investigated. The results indicated that there existed a synergetic effect in the co-pyrolysis of bituminous coal and biomass in this pressured fluidized bed reactor, especially when the condition of bituminous coal and biomass blend ratio of 70:30(w/w), 600 °C, and 0.3 MPa was applied. The addition of biomass influenced the tar and char yields and gas and tar composition during co-pyrolysis. The tar yields were higher than the calculated values from individual pyrolysis of each fuel, and consequently the char yields were lower.The experimental results showed that the composition of the gaseous products was not in accordance with those of their individual fuel. The improvement of composition in tar also indicated synergistic effect in the co-pyrolysis.     

Application of chemometrics to study the kinetics of coal pyrolysis: A novel approach

In present investigation, chemometric tools, principal component analysis (PCA) and Hierarchical clustering analysis (HCA) are used to get the linkage between the coal properties and kinetics of pyrolysis. Thermo gravimetric analysis (TGA) of 10 perhydrous Indian coals was done. Devolatilization of these coals showed five independent reactions. Kinetic parameters were calculated for individual reaction. Activation energy and weight loss of each reaction has been analyzed as a function of coal properties (moisture, volatile matter, ash, fixed carbon, carbon, hydrogen, nitrogen and sulfur). By applying chemometric, was extracted information about the linkage between activation energies of each reaction and coal properties. The mathematical treatment of data has provided conclusions on properties of coal and kinetic parameters.     

劣质煤发热量的标准加入法测定

测定劣质煤的发热量时，在煤样中加入标准苯甲酸，帮助样品燃烧完全。测定出此混合样的弹简发热量，则煤样的弹简发热量等于混合样弹简发出的热量减去标准苯甲酸所发出的热量再除以煤样质量，根据弹简发热量即可算出煤样的高低位发热量。     

不同吨焦煤耗计算方法的探讨

利用吨焦煤耗的4种估算方法,分别对7m焦炉和7.63m焦炉的吨焦煤耗进行计算。分析表明,干熄焦烧损率对吨焦煤耗影响较大。利用焦炉装煤量和电子秤配煤2种估算方法能较准确地反映实际吨焦煤耗。     

Individual contributions to the overall microelement concentrations in coal

The microelement concentrations in coal represent the sum of contributions from the organic mass, the mineral impurities, and the initial plant matter. These contributions are mutually independent and may differ very considerably. Generally, the microelement concentrations in coal are determined by their content in the organic mass. Identification of the individual contributions to the overall microelement concentrations in coal is of interest in assessing the rare-metal content of coal and means of extracting microelements. Unsatisfactory and often conflicting results are obtained by existing methods of identifying those contributions (by separation of the coal into fractions of different density; by comparison with the abundance ratios in the aleuropelite fraction; by correlation with the ash content). A method is proposed for statistical resolution of the individual contributions to the overall microelement concentrations in coal.     

Thermogravimetric study of coal and petroleum coke for co-gasification

As a preliminary study of gasification of coal and petroleum coke mixtures, thermogravimetric analyses were performed at various temperatures (1,100, 1,200, 1,300, and 1,400 °C) and the isothermal kinetics were analyzed and compared. The activation energies of coal, petroleum coke and coal/petroleum coke mixture were calculated by using both a shrinking core model and a modified volumetric model. The results showed that the activation energies for the anthracite and petroleum coke used in this study were 9.56 and 11.92 kcal/mol and reaction times were 15.8 and 27.0 min. In the case of mixed fuel, however, the activation energy (6.97 kcal/mol) and reaction time (17.0 min) were lower than the average value of the individual fuels, confirming that a synergistic effect was observed in the coprocessing of coal and petroleum coke. This work was presented at the 6 ^th Korea-China Workshop on Clean Energy Technology held at Busan, Korea, July 4–7, 2006.     

Clinkering Properties of Individual Fractions of Enriched Poorly Clinkering Coal

The clinkering properties of individual fractions of enriched poorly clinkering coal with limited metamorphic development are studied. Plastometric and dilatometric data are employed in studying the clinkering properties. It is found that, with change in the density of the individual fractions, their clinkering properties also change significantly. The results suggest that the difference in clinkering properties of individual fractions of enriched poorly clinkering coal is mainly due to the different quantity of liquid mass, which also differs in viscosity. On the basis of the results, optimal fractions of enriched poorly clinkering coal for use in coking batch may be formulated.