高硫无烟煤降灰脱硫可行性试验研究

重点分析了王河煤矿高硫无烟煤的煤质特征、可选性及降灰脱硫的可行性。研究表明:简单地利用现有的物理分选方法很难将该矿区高硫无烟煤精煤硫分降到1%以下,而且精煤理论产率很低;如果将精煤硫分控制在1.2%～1.3%,并采用配煤等技术,可使精煤产率达到一个相对合理的水平;可以从高硫煤洗矸中选出硫精矿,实现资源的综合利用;也可考虑发展煤化工项目。     

高硫煤中形态硫的热解迁移特性

对西北地区石炭纪高硫煤进行热解实验,考察了热解温度(200℃～1 000℃)和热解停留时间(20min～100min)对煤中形态硫的迁移特性的影响,并通过FTIR分析了热解过程中半焦的结构变化情况.研究表明,高硫煤中全硫随热解温度的升高先减小后增大,在600℃时达到最低;硫酸盐硫的含量较低,维持在0%～0.5%之间;硫化铁硫随着热解温度的升高逐渐减小;有机硫随热解温度的升高先减小后增大,在500℃时达到最低.无机硫脱除率高于有机硫脱除率.煤热解过程中氧和硫等杂原子官能团在半焦中不断减弱.     

高硫煤作为炼焦煤掺合料研究

为了节约我国稀缺的炼焦煤资源和提高经济效益,从而使高硫煤作为炼焦配煤的掺合料成为可能,采用理论推理和实验对比的方法,进行了高硫煤的炼焦硫分的转化实验和不同有机硫含量配比实验。结果表明,高硫煤中富含有机硫容易出低硫焦煤,无机硫中黄铁矿在高温分解时会在煤的有机质作用下无机硫向有机硫的转化。瘦煤、焦煤、肥煤、气煤在干燥基全硫的质量分数为1.00%～2.50%时,瘦煤、焦煤、肥煤、气煤中优化的有机硫的质量分数一般小于70%、70%～90%、大于90%、大于95%。该方法是一种经济可靠,具有模拟生产效果的特点。     

采用摇床分级重选复杂高硫煤的试验研究

为对复杂高硫煤进行脱硫降灰研究,根据不同粒级中硫分分布差异以及硫的主要赋存形态为硫铁矿,利用摇床进行分级重选试验;将原煤分成0.5~1 mm和1~3 mm两个粒度级,分别考查了摇床冲洗水量、冲程、床面倾角等工艺参数对分选指标的影响,确定了较为合理的工艺条件;然后对两个粒级摇床粗选精煤合并进行精选,以进一步脱硫降灰;经过两段摇床重选,精煤硫分由6.77%降低到2.15%,精煤灰分由35.10%降低到12.77%。     

兖州矿区高硫煤赋存特征与加工利用工艺分析

兖州矿区高硫煤中的硫以无机硫为主 ,约占全硫的 62 % ,破碎后对硫铁矿硫的解离效果不好 ,适宜采用跳汰分选降硫。由于选后煤中硫分仍高于 1 % ,建议高硫煤与低硫煤配合 ,或在高硫煤中加入固硫剂 ,以满足用户对硫指标的要求。     

丙二醇-氢氧化钾脱除煤中有机硫的研究

以重庆万盛高硫煤作为研究对象,选用硝酸预处理去除无机硫,并采用单因子法考察了煤浆浓度、反应时间、反应温度、丙二醇与氢氧化钾的配比对煤中有机硫脱除率的影响.结果表明,对于粒径小于0.075 mm的煤样,丙二醇-氢氧化钾脱除煤中有机硫的适宜条件为:煤浆浓度0.05 g/mL,反应时间90 min,反应温度180℃,丙二醇与氢氧化钾的配比为1∶1.在此条件下,有机硫从0.72%降到0.35%,脱除率为51.4%.     

渭北煤中硫的赋存特性研究

对渭北煤中硫的赋存特性进行了较为系统的研究,经对煤样进行工业分析,全硫、形态硫、煤灰成分的测定,渭北煤呈现出灰分含量高、水分含量较低、中高挥发分、高硫含量等特征。对原煤样进行XPS测试,煤中硫的存在形态较为复杂,其中有机硫所占比例非常大,样品表面的有机硫含量达到80%。而在有机硫中,主要是噻吩类和硫醇硫醚型硫,共占到有机硫含量的96%。由此可见在研究渭北煤中的硫脱出迁移特性必须着重考虑有机硫的脱出迁移特性。研究煤中硫的赋存特性,为煤的脱硫提供具有应用价值的数据和脱硫方法,对于减少二氧化硫的排放具有重要意义,符合国家可持续发展战略的要求。     

渭北煤中硫的赋存特性研究

对渭北煤中硫的赋存特性进行了较为系统的研究,经对煤样进行工业分析,全硫、形态硫、煤灰成分的测定,渭北煤呈现出灰分含量高、水分含量较低、中高挥发分、高硫含量等特征。对原煤样进行XPS测试,煤中硫的存在形态较为复杂,其中有机硫所占比例非常大,样品表面的有机硫含量达到80%。而在有机硫中,主要是噻吩类和硫醇硫醚型硫,共占到有机硫含量的96%。由此可见在研究渭北煤中的硫脱出迁移特性必须着重考虑有机硫的脱出迁移特性。研究煤中硫的赋存特性,为煤的脱硫提供具有应用价值的数据和脱硫方法,对于减少二氧化硫的排放具有重要意义,符合国家可持续发展战略的要求。     

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。     

高硫煤中黄铁矿浮选抑制试验研究

为提高高硫煤的浮选脱硫效率,以新峪选煤厂高硫煤泥为研究对象,分析了高硫煤的粒度组成及硫形态分布,研究煤浆质量浓度、捕收剂、起泡剂和抑制剂种类及用量对高硫煤浮选脱硫效果的影响。结果表明,新峪选煤厂煤泥硫分高达3.57%,属于高硫煤,黄铁矿硫含量较高为2.18%,可通过物理分选方法脱除。当煤浆质量浓度为80 g/L,纳尔科油用量为200 g/t,仲辛醇用量为100 g/t,巯基乙酸用量为400 g/t时,高硫煤浮选效果最好,精煤硫分为2.35%,可燃体回收率为69.23%,脱硫效率最高为24.76%。     

氢气纯度分析方法准确性的探讨

ONACCURACYOFANALYSISOFOFHYDROGEN1前言我公司目前应用的氢气纯度分析方法有两种,一种是爆炸反应法,另一种是焦性没食子酸吸收法。几年来,人们对两种分析方法的准确性曾有过褒贬不一的评论。这里我们也谈谈自己粗浅的观点。2爆炸法测定氢气纯度一定量的氢气样品与适量的空气之均匀混合物因反应后生成液体水而引起气体体积减少,减少的体积等于参加反应气体体积之和。其中l／3为氧气,2／3为氢气。根据氢气取样量和反应前后混气体体积之差,以及氢气在反应中的体积比例关系,可计算出样品的氢气纯度。计算公式式中：A一混…     

COMPARISON OF METHODS OF ANALYSIS OF GYPSUM1

The different analytical methods proposed for the evaluation of gypsum have been subjected to an experimental test. A combination method, consisting of a fusion with KHCO₃ and determination of CaO by KMnO₄ titration, the SO₃ by Andrews method of titration of BaCrO₄ has been found to give very reliable results with the least consumption of time.     

SEDIMENTATION OF BINARY MIXTURES OF PARTICLES OF UNEQUAL DENSITIES AND OF DIFFERENT SIZES

A model is developed for the sedimentation from a suspension of two particle species of unequal densities and of different sizes. The composition and the thickness of various layers in the sediments are predicted using graphical and analytical methods. The model predictions were in excellent agreement with experimental results, when the particle size ratio was ≥ 108. When size ratio of the particles was 2.60 and 4.31 the agreement occurred in about 50 percent of the cases.     

HEASUREHENT OF INSTANTANEOUS RATES OF LOSS OF VOIATILE COMPOUNDS DURING DRYING OF DROPS

A novel technique serves to monitor instantaneous rates of loss of a volatile solute from a suspended drop during drying. A highly sensitive electron capture detector is used to monitor concentrations of SF6 released into a flowing gas stream from a suspended, drying drop. Simultaneously, the appearance and morphological development of the drop are monitored with a video camera. This provides the wherewithal of relating instantaneous rates of loss of the volatile solute to particular events during the development of particle morphology.

Initial experiments have been carried out with drops of aqueous solutions of glucose, sucrose, maltodextrin and coffee extract. The results clearly display the onset of the volatiles-retentive selective diffusion phenomenon. There is also substantial loss of the volatile component later in the drying process, when the drops undergo repeated ex ansion, bursting and cratering due to the formation of internaf bubbles. These experiments appear to be the first quantitative demonstration of major losses accompanying changes in drop morphology.     

茶多酚提取方法进展

本文综述了国内外现有茶多酚提取方法的现状以及近期的研究进展，并对其优缺点进行了评价。这将有助于中低档茶的综合利用和茶多酚的进一步开发应用。     

ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES

Viscosity of Simple Soda-Silicate 500° to 1400°C Comparison of the results given by English with those of Washburn, Shelton and Libman, indicates a discrepancy in the absolute values of log₁₀ viscosity amounting to 0.6, those of Washburn et al., being relatively too high. If correction for this is made, the isothermal curves of log₁₀ viscosity as a function of soda content are smooth up to 50% Na₂O, showing no inflection. The observations as a function of temperature T are all represented within accidental error by an equation of the type where all three constants vary regularly with the composition. Change of Viscosity of Glass (6SiO₂, 2Na₂O) due to Molecular Substitution of CaO, MgO and Al₂O₃ for Na₂O The effect is clearly brought out by plotting (from the results of English) the change of log₁₀η due to the substitution as a function of temperature. The curves each show a sharp bend at a temperature between 840° and 1050°C, which is designated the aggregation temperature T_a. If we divide these curves by the corresponding percentage substituted, we get curves for each oxide which are straight and parallel below the aggregation temperatures, the slopes (increase of change of log₁₀η per 100°C) being −0.056 (CaO), −0.055 (MgO), −0.018 (A1₂O₃) per per cent oxide substituted. For substitution of 1/2 molecule the slopes are −0.325 (CaO), −0.23 (MgO) and −0.18 (Al₂O₃) per 100°. At the aggregation temperature the change of log₁₀η per per cent is a minimum, 0.03 to 0.06 for CaO, 0.12 for MgO, 0.07 for Al₂O₃. Evidence of Aggregation in Glasses, from viscosity Measurements The sharp bends in the plots of change of log₁₀η due to substitution of an oxide for Na₂O, suggest the beginning of molecular aggregation at these temperatures. These aggregation temperatures are close to the devitrification temperatures, but the effect on the viscosity curves cannot be due to actual devitrification since it does not change with time. Taking the aggregation temperatures as equal to devitrification temperatures, additional isotherms are roughly sketched into the equilibrium triangle of the system Na₂O-CaO-SiO₂. Change of Viscosity of Glass (4SiO₂, 2Na₂O) due to of Substitution of B₂O₃ for SiO₂ The change of log₁₀η (from the results of English) is plotted as a function of temperature, and also the change of log₁₀η per per cent B₂O₃. The curves are more complex than for the substitution for Na₂O.     

环氧树脂羟基值测定方法的研究

利用乙酸酐、吡啶和浓硫酸混合的乙酰化试剂测定环氧树脂中羟基值含量的方法具有操作简便、滴定终点明显和分析结果误差小等优点。     

骑式摩托车油箱喷涂工艺的改进

面对日益激烈的市场竞争,摩托车油箱外观质量越来越成为影响销售的因素之一。文章介绍了改进工艺后的油箱涂装,该涂装体系提高了油箱外观的丰满度,降低了油箱涂装的生产成本。     

几种针状焦性能对比

针状焦分石油系和煤系两大类,这主要取决于针状焦的原料来源。在同一系列中由于原料不同和工艺条件不同 ,针状焦的各自性能也不相同。针状焦是生产超高功率石墨电极和高功率石墨电极的主要原料 ,针状焦的性能对石墨电极的质量有至关重要的影响。所以对针状焦性能以及其对石墨电极质量影响的研究十分必要的。以下是常用的几种进口针状焦和国产针状焦的性能对比。１原料性能分析对比原料试样包括４种针状焦 ,其中两种为进口针状焦：三菱针状焦和新日化针状焦;另两种为国产针状焦：鞍山针状焦和锦州针状焦。其中除锦州针状焦是石油系针状焦外…     

聚酰亚胺的合成法

本文评述了缩聚型聚酰亚胺的主要合成方法和近年来国际上在合成中所做的探索。