降低电煅无烟煤电能消耗的工艺技术探讨

根据电煅炉煅烧无烟煤的工艺原理，通过调整上部电极长度、烟道闸板及改变电煅无烟煤前上料系统通风除尘灰的排放方向等工艺控制方法，对电煅无烟煤电耗进行研究。实践证明，这些工艺条件的实施，有效地降低了电煅无烟煤的电耗，降低了生产成本。     

电煅烧炉偏流问题的探讨及解决

为提高电煅无烟煤质量的均匀性，分析了电煅烧炉偏流导致电煅无烟煤质量不均匀的3种原因——排料部位场块结焦、底部电极倒塌、煅前加料工艺设计不合理，并提出了相应的解决方法。结果表明，煅前加料工艺设备的改造，对电煅无烟煤质量的稳定提高起到了关键作用。     

无烟粉煤催化气化含碱灰渣的煅烧脱碱

在具有温控的小型高温加热炉中,通过静态煅烧研究了温度、时间及助剂对高变质程度无烟粉煤催化气化后的含碱灰渣中碱含量的影响,结果表明：最佳的脱碱煅烧温度及时间分别为870℃和30 min;最佳的脱碱助剂高岭土在其添加浓度为5％时,灰渣脱碱率可达100％.采用X射线粉晶衍射及扫描电镜对煅烧后的灰渣进行表征,揭示了含碱灰渣煅烧脱碱过程的实质,即在适宜煅烧温度下,含碱灰渣中被活化的主要矿物质SiO₂（形成玻璃网络氧化物）、Al₂O₃（修饰中间氧化物）和熔融并分解的Na₂CO₃（分解为修饰网络氧化物Na₂O）等发生化学反应转变为中性物质霞石（NaAlSiO₄）及其他无定形复合硅酸盐,从而降低了灰渣中的碱含量.     

影响电煅无烟煤电阻率的几个因素

对电煅无烟煤电阻率与一次送电电流和温度之间的关系进行了试验研究，得到了它们之间的关系表面式模型，据此，可以在环境温度，炉壳温度变化不大的情况下，预测电煅无烟煤的电阻率，另外还分析了电阻率与真密度，原煤粒度分布，加排料量，煅烧区长度，电流密度之间的相关性，结果表明，电煅无烟煤电阻率及其分布与电流密度，煅烧区长度，原煤粒度分布，加排料量密切相关。     

高温模压炭砖的研制

介绍了炼铁高炉用高温模压炭砖的研制概况。重点介绍了"抗铁水"炭砖研制情况,选用电煅煤和高温电煅煤为骨料,煤沥青作黏结剂在特制设备中快速压型烧结试制出高温模压炭砖。对原材料优化给出了炭砖的耐压强度、铁水溶蚀指数、透气度依赖于高温电煅煤含量的三个回归方程。还给出了3种炭砖的抗热震因子的结果。同时就远洋公司生产的高温模压炭砖质量指标与国内外优质炭砖进行了对比分析。     

Industrial use of low-phosphorus anthracite in the production of high-carbon ferrochrome

The use of anthracite in the production of high-carbon ferrochrome is assessed. The theoretical and technological aspects of electrothermal production of high-carbon ferrochrome are analyzed. The physicochemical characteristics of anthracite and coke nuts are compared. It is established that the ash content of anthracite is low. More importantly, its content of phosphorus and sulfur is very low. An advantage of anthracite is its high electrical resistance. The use of anthracite in the production of high-carbon ferrochrome in 21-MV A furnaces reduces the consumption of reducing agent (by 1.9%) and electric power (by 6.8%). The extraction of chromium is practically unchanged. The production costs (per 1 t of high-carbon ferrochrome) are reduced. The use of anthracite in more powerful furnaces (63 MV A) permits significant increase in the working voltage and decrease in power consumption by 2.0–2.5%. The phosphorus content in the ferrochrome is reduced with increase in anthracite content in the batch.     

不同煤质煤焦燃烧模型的研究

在高温悬浮反应试验台架上,对烟煤、无烟煤、高挥发分褐煤等煤焦的燃烧模型进行了研究。通过传递函数修正后的燃尽率与时间的关系曲线与收缩核模型、收缩圆柱体模型、化学反应级数等模型进行拟合,通过相关系数来选取最合适的燃烧模型。运用这种方法求取了D烟煤、X低挥发分煤、K褐煤的煤焦燃烧模型和S无烟煤、L无烟煤等煤焦的燃烧模型。列举了D烟煤与S无烟煤煤焦燃烧模型的实验曲线与模拟曲线,并用求出的模型对同种煤焦的其它工况进行求解,所得的结果与实验的测定值比较吻合,说明了求取模型方法的可靠性。模型的正确选择为分解炉中煤粉燃烧与碳酸钙分解的耦合研究奠定了基础。     

无烟煤粉煤的利用问题

我国无烟煤产量近２．５亿吨，据无烟煤生产现状和煤质特性，主要问题是灰分高的无烟粉煤大量积压。利用无烟粉煤的优化顺序：作高炉喷吹燃料，工业型煤，炼焦配料，煤基活性炭和炭其它高附加值的产品原料等。     

焦化除尘灰的气力输送与利用

介绍了焦化除尘灰气力输送的原理、流程、特点、运行以及焦化除尘灰用于高炉煤粉喷吹的情况,对关键技术问题进行了探讨。生产实践表明,气力输送方式实现了长距离无污染输送,可多点取料和卸料,过程自动控制。还可以定量与高炉喷吹无烟煤混配,置换部分无烟煤,实现了除尘灰无二次污染的综合利用。     

粒径对福建无烟煤在CFB锅炉中燃尽的影响

建立了福建无烟煤细颗粒燃烧模型,计算了其在容量35 t/h循环流化床锅炉炉膛内的燃尽时间和一次通过炉膛的停留时间,分析了不同粒径煤颗粒在不同燃烧温度和不同烟气流速时在CFB锅炉内的燃尽时间和停留时间的变化差异. 实验研究了福建无烟煤粒径对飞灰碳含量的影响及燃尽的影响. 结果表明,细煤颗粒的燃尽时间与停留时间均随粒径增大而增长,但燃尽时间增幅更明显,颗粒一次通过炉膛完全燃尽的临界粒径约为0.15 mm;粒径越大的颗粒其停留时间和燃尽时间对烟气流速和燃烧温度变化越敏感;无烟煤入炉粒径明显影响CFB锅炉飞灰含碳量,选用粒度为3~8 mm的偏粗颗粒为宜.     

Flash induction calcination: A powerful tool for total template removal and fine tuning of the hydrophobic/hydrophilic balance in SBA-15 type silica mesoporous materials

A new rapid calcination method has been used to completely remove the organic template from SBA-15 ordered mesoporous silica, and to preserve a high number of silanol in these materials. This calcination method provided by an induction furnace was found to considerably reduce the calcination time and therefore the energy consumption associated. Moreover, adjustment of both calcination temperature and duration allowed tuning the hydrophobic/hydrophilic balance of the mesoporous SBA-15 silica materials. For comparison, short and long time conventional muffle furnace calcination was performed. The induction calcination was also successfully applied to different type of mesoporous silica materials such as SBA-16 and MCM-41.     

内在矿物质对煤焦燃烧特性影响的动力学研究（Ⅰ）等温热重研究

选择宁夏地区2种烟煤和2种无烟煤作为实验煤样,用浮沉法得到灰分在30％左右的煤粉在马弗炉上900℃制焦,然后用化学脱灰法处理煤焦样,得到超低灰煤焦样。在WCT-2型热重分析仪上,在消除内、外扩散影响的条件下对高灰煤焦和脱灰煤焦进行等温热重实验。动力学分析的结果表明：2种烟煤焦脱灰后的活化能降低,2种无烟煤焦脱灰后的活化能升高;烟煤中的矿物质对烟煤的燃烧有阻碍作用,无烟煤中的矿物质对烟煤的燃烧有促进作用。     

富氧条件下煤粉气流的着火性能变化

利用一维火焰炉对不同富氧条件下的煤粉气流着火燃烧特性进行了研究,得到了富氧条件下煤粉气流的着火性能变化规律。研究结果表明:随着助燃气体氧浓度的提高,各煤样的着火温度均大幅下降,其中低挥发分煤种在着火方面对富氧条件的改善更为敏感,即富氧条件的改善可减弱煤种间着火性能方面的差异性;随着氧浓度的提高,煤粉气流的着火方式明显从均相着火向非均相着火转变,其中燃用褐煤时发生着火方式转变所对应的氧浓度为50%~60%,燃用烟煤时约为40%,燃用贫煤和无烟煤时都约为30%;对于烟煤和褐煤,随着氧浓度的提高,对应的最佳煤粉浓度值先增大后减小,而对于贫煤和无烟煤,由于其在整个实验氧浓度范围内基本上都以"非均相着火"为主,因此随着氧浓度的提高,对应的最佳煤粉浓度的值基本上呈缓慢下降的趋势。     

电煅无烟煤煅烧均匀度分析

对取自4个不同厂家的电煅无烟煤用溶剂萃取法分别分离成若干部分,然后测试其电阻率,并绘制成电阻率分布直方图,通过直方图,可以对不同来源的电煅无烟煤的煅烧均匀程度做出定量的评价。     

Structure and properties of thermoanthracites obtained under industrial conditions

The article presents the characteristics of thermoanthracites manufactured from Donets Basin vitrinite anthracite and Gorlovo-basin inertinite anthracites, obtained in various industrial units: a shaft furnace, a drum rotary kiln, an electric calciner, and a graphitization furnace. The influence of the operation modes of the devices on the structure and properties of the resulting products is analyzed.     

A model of the electrical conductivity of anthracite and graphite dispersions in electrolytes

The electrical conductivity of anthracite and graphite dispersions in the solutions of potassium chloride was measured. A linear increase in the electrical conductivity as a function of the weight fraction of a dispersed phase was observed in the region of electrolyte concentrations of 0.0005?C0.01 M. In 0.1 M solutions, the dependence of the electrical conductivity of a suspension on the weight fraction of a dispersed phase (0.1?C15 wt %) decreased with the subsequent increase. A model was proposed for the electrical conductivity of anthracite and graphite dispersions in electrolytes; in accordance with this model, charge transfer due to the electrophoretic mobility of particles makes the main contribution to an increase in the electrical conductivity. Different electrical conductivity components (specific surface conductivity) calculated from the Bikerman equation and based on the model proposed were compared.     

糯东矿无烟煤分选工艺的选择

为提高无烟煤分选效果,分析了糯东矿煤质特性、粒度组成和可选性,确定原煤属低中灰~中灰、中高硫~高硫、低磷、特低抗破碎强度无烟煤,煤中硫以无机硫化铁硫形式为主;煤中细粒级含量较高,需加强细粒煤分选,粗煤泥可单独分选,产品易脱水;原煤可选性为中等可选。结合原煤性质,确定糯东选煤厂产品定位为:17煤分选中、小块煤用于化工用煤,末精煤用于高炉喷吹用煤;20煤分选中、小块煤用于化工用煤,混煤用于动力用煤。通过对比分析常用选煤方法及工艺的特点,确定糯东选煤厂无烟煤分选方案为:选前+100(80)mm检查性手选、-100(80)mm混合跳汰入选、粗煤泥干扰床分选机(TBS)分选、细煤泥浮选、尾煤浓缩压滤的联合工艺流程。     

固相反应法制备纳米ZnO及其晶粒生长动力学

以乙酸锌和草酸为原料,采用低热固相化学反应法制备纳米氧化锌的前体,通过微波和马弗炉两种焙烧方式焙烧制备得到纳米氧化锌,考察了焙烧温度和时间对纳米氧化锌粒径的影响。使用透射电镜、热重-差热、傅里叶变换红外光谱仪和X射线衍射仪对前体和纳米ZnO进行表征;采用晶粒生长动力学唯象理论计算得出纳米氧化锌在这两种焙烧方式下的晶粒生长动力学规律。结果表明,前体为ZnC2O4?2H2O,随着焙烧温度的提高,纳米氧化锌晶粒迅速长大,在相同焙烧温度和时间下,微波焙烧氧化锌的晶粒尺寸要明显大于常规焙烧方式。微波焙烧和常规焙烧下氧化锌的晶粒生长平均动力学指数分别是6.114和6.858,晶粒生长的平均活化能分别为70.67 kJ/mol和52.13 kJ/mol。     

Facile preparation and characterization of lanthanum oxide powders by the calcination of lanthanum carbonate hydrate in microwave field

Micron-sized lanthanum oxide powders are prepared by the calcination of lanthanum carbonate hydrate in microwave field. The decomposition process of lanthanum carbonate hydrate was analyzed by TG-DSC and indicates the reaction undergoes three stages, resulting in the generation of lanthanum oxide at 770 °C. For microwave assisted calcination, XRD patterns demonstrate that hexagonal La₂O₃ structure is initially formed after calcination at 650 °C for 2 h, and FT-IR analyses confirm the decomposition of precursor is complete after calcination at 750 °C for 2 h. SEM investigations reveal that 800 °C is the optimal calcination temperature to generate La₂O₃ powders with uniform morphologies. In comparison, conventionally calcination experiments are carried out in electrical furnace. Both XRD and FT-IR analyses are in consistence with TG-DSC, which indicate the temperature required for fully decomposition of lanthanum carbonate hydrate by conventional heating is higher than that of microwave heating. SEM images present irregular morphologies and wide particle size distribution of conventionally prepared samples. All the techniques are utilized to prove the feasibility of decomposing La₂(CO₃)₃ to generate La₂O₃ in microwave field and highlight the advantages of microwave heating.     

冶金炉窑用高强型煤黏结剂优配的实验研究

以湖南金竹山无烟煤为原料，采用正交实验法对冶金炉窑用型煤复合黏结剂各组分的配比及型煤成型的主要工艺参数进行了实验研究．结果表明，镁基黏结剂和成型压力对型煤的抗碎性能影响显著．型煤黏结剂各组分相对于原料煤粉的最优配比为：镁基黏结剂取4％，生物质纤维取1％，固化剂取0．6％，减水剂取0．12％．型煤成型的最佳工艺参数为：成型压力20kN，成型水分17％，烟煤掺量10%，煤料粒度组成：3mm～2mm颗粒为8％，2mm～1mm为12％，1mm～0．5mm为10％，0．5mm以下为70％．评估了该复合型煤黏结剂的成本，分析了其作用机理．