Colourless distributed combustion effects on a pre-mixed coke oven gas flame

Fuels consisting of high hydrogen concentration can be consumed under colourless distributed combustion (CDC) to suppress flashback tendency in premixed conditions. Higher NO_X challenges can also be overcome through CDC. For those purposes, coke oven gas was consumed under CDC within the scope of this study. To achieve CDC, ${\mathrm{N}}_2$ or ${\mathrm{CO}}_2$ diluents were introduced into the oxidizer so that oxygen concentration in the oxidizer would be decreased from 21% O₂ to its lean blow-off limits. Excess air ratios were determined as λ = 1.2 and λ = 1.5 along with a thermal power of 10 kW under premixed conditions. A commercial computational fluid dynamics code was used to predict temperature distribution and ${\mathrm{NO}}_X$, CO, and ${\mathrm{CO}}_2$ emissions. 162-step reactions created with GRI-Mech 3.0 chemical kinetics was integrated to the eddy dissipation concept combustion model. The temperature and ${\mathrm{NO}}_X$ profiles predicted were compared with the experimental results. Consistency was achieved at ~95% for temperature profiles, and almost 100% for ${\mathrm{NO}}_X$ profiles between the measured and the predicted ones. According to the results, it is concluded that a more homogeneous temperature distribution with the ~21% decrease in the maximum temperature was observed, and there was about 96% decrease in ${\mathrm{NO}}_X$ level. It was also demonstrated that using ${\mathrm{CO}}_2$ as a diluent is more effective in terms of temperature distribution over the combustor and ${\mathrm{NO}}_X$ reduction, while dilution with ${\mathrm{N}}_2$ is more effective in terms about 70% in decrease on CO.     

DIFFUSION COEFFICIENTS FOR PREDICTING ROUGH RICE RE-WETTING BEHAVIOR

ABSTRACT

Thin-layer re-wetting experiments were conducted with medium grain rough rice in the temperature range of 17.8 to 45^°C and for relative humidities between 56 and 89.3%, with initial moisture contents in the range of 10.26 to 12.71% dry-basis to determine the diffusion coefficient of rough rice. Recent efforts to characterize the re-wetting characteristics of rough rice are summarized. New equation for temperature dependent liquid diffusion coefficients for medium grain rough rice are presented. The diffusion coefficient in re-wetting was lower than the drying. The results presented here, over typically five day re-wetting, will be useful in studying the longer term moisture transfer process occurring during ventilated storage.     

焦炉烟尘治理工艺探讨

对国内主要的焦炉除尘工艺进行了介绍分析,找出了各工艺的优缺点,为除尘工艺的选择及现有工艺的改造提供了可靠的依据,从而达到除尘效率高、设施运行安全可靠、费用低的目的.     

焦化废水催化氧化处理的工艺条件实验

利用芬顿(Fenton)试剂的催化氧化性对焦化废水进行初步的处理,使其CODcr值除去率达80%以上,再用活性炭进行深度处理,使其CODcr值<40mg·L-1,总除去率达98%以上.     

焦炭塔操作仿真培训系统设计

为了避免焦化生产过程中人为原因造成的安全事故,设计了一套焦炭塔操作仿真培训系统.首先采用模块化的设计方法,每个装置都是一个单片机构成的仿真.在每个阀门模块上设置有三个按键用以模拟实际阀门的三个操作按钮,阀门模块上还设有一排发光二极管( LED)灯,在仿真过程中模拟阀门的开度,焦炭塔模块上也设有LED灯,用以模拟塔顶底盖的开度和塔内物料的百分比.各模块之间使用标准MODBUS-RTU协议进行连接,共同组成焦化生产工艺流程.最后该装置与内操组态系统连接,完全模拟焦炭塔生产过程中的行为属性.因此操作员工可以在仿真系统上模拟延迟焦化的工艺流程,熟悉实际生产过程中的每一个步骤.通过实际使用,该系统能正确模拟焦炭塔的生产过程流程,方便操作工的培训.通过更改软件还可以让系统适应不同炼厂焦化操作工艺的需求.     

石油污染土壤含水率的测定

采用烘干法对原油污染壤黏土、原油污染砂土、柴油污染壤黏土和柴油污染砂土的含水率进行了校正.结果发现,烘干过程中石油和水分的挥发互不影响,每种油品挥发损失比例固定.通过含水率与含湿率之间的关系,提出了试验用石油污染土壤含水率的校正公式.     

Effect of the catalyzing combustion of coke breeze on the energy saving in sinter process

Ａｓｏｎｅｏｆｔｈｅｌａｒｇｅｓｔｅｎｅｒｇｙｃｏｎｓｕｍｐｔｉｏｎｐｒｏ ｃｅｓｓｅｓｉｎｔｈｅｉｒｏｎａｎｄｓｔｅｅｌｉｎｄｕｓｔｒｙ ,ｓｉｎｔｅｒｉｎｇｍｉｌｌｓ′ｅｎｅｒｇｙｃｏｎｓｕｍｐｔｉｏｎａｃｃｏｕｎｔｓｆｏｒｓｏｍｅ 1 0 %ｏｆｔｈｅｔｏｔａｌｆｏｒｓｔｅｅｌｐｒｏｄｕｃｔｉｏｎ[1] .Ｈｏｗｅｖｅｒ,ｔｈｅｅｎｅｒｇｙｃｏｎｓｕｍｐｔｉｏｎｉｎｓｉｎｔｅｒｉｎｇｃｏｖｅｒｓｓｏｌｉｄｆｕｅｌｓ,ｇａｓｅｏｕｓｆｕｅｌｓ,ｅｌｅｃｔｒｉｃｉｔｙａｎｄｗａｔｅｒｃｏｎｓｕｍｐｔｉｏｎ ,ｅ…     

铝管退火表面形成残焦的原因剖析

通过铝管拉拔试验及加热失重试验，剖析了不同的润滑剂在不同温度下形成残焦的原因，并由热重分析得到了证实。进而优选出一种新型润滑剂为Ｘ润滑油。     

焦炭与焦炭化工产品市场分析与需求预测

笔者对世界和中国焦炭工业以及焦炭化工产品chemicalproductionofthecoking的现状和未来进行了分析和需求预测。还结合山西焦煤集团西山煤矿总公司的焦炭化工工业的现状及发展规划,对以炼焦煤气为主要原料生产甲醇、二甲醚、醋酸和醋酐以及甲醛和聚甲醛的生产现状、市场进行了分析与预测。     

超临界条件下甲基萘与甲醇烷基化反应

引　言2 ,6 二甲基萘 (2 ,6 DMN)是生产新型高性能聚酯材料聚萘二甲酸乙二醇酯 (PEN)的重要原料 .目前已工业化的邻二甲苯与丁二烯烷基化生产2 ,6 DMN路线生产步骤多 ,工艺过程复杂 ,生产成本高 ,制约了PEN的发展[1,2 ] .HZSM 5沸石是一种具有强酸性、高硅铝比和独特孔道结构的分子筛 ,对许多正碳离子反应有良好的择形催化性能[3] .HZSM 5催化甲基萘 (DMN)与甲醇烷基化合成 2 ,6 DMN路线工艺过程简单 ,产品选择性高 ,是一条具有发展前景的技术路线[4 ] .然而 ,在常压下进行烷基化反应时 ,反应活性低 ,催化剂容易因结焦而失去原有的活性[5～ 7] .超临界流体具有良好的溶解和扩散性能 .在超临界条件下进行的化学反应不仅可以提高催化剂的反应活性 ,而且还可以原位维持非均相催化剂的活性 ,延长催化剂的寿命[8,9] .本文正是基于超临界流体独特的性质 ,探索在超临界条件下甲基萘与甲醇烷基化反应中提高反应活性和延长催化剂寿命的可能性 .1　实验部分1 1　催化剂的制备NaZSM 5沸石 (硅铝比为 38)由南开大学催化剂厂提供 .在 80℃下用 1mol...