温度对煤样罐内煤体瓦斯解吸的影响

采用特制的瓦斯解吸试验系统，对阳煤五矿15号煤煤样进行了不同吸附和解吸温度条件下煤屑瓦斯解吸量测定实验及恒温和变温吸附解吸条件下煤样罐中煤屑瓦斯解吸过程中温度变化测定实验。试验结果表明:煤屑在40 ℃吸附后，在27 ℃解吸时速度明显低于40 ℃下解吸速度，30 ℃吸附40 ℃解吸明显高于40 ℃吸附27 ℃解吸的解吸速度；气体分子的吸附解吸过程伴随着多孔介质系统的能量改变而导致了温度变化，热量从煤样罐外围环境传导到煤样需要一定时间，在瓦斯解吸过程中，外界温度的急剧变化不会立即对解吸扩散过程产生影响，在这一时间阶段内，对煤样温度变化起主要决定作用的还是煤解吸瓦斯过程中自身的吸热反应，但一定时间后其决定作用将会是外界温度。     

降温过程对高地温煤层瓦斯解吸的影响

选用唐口煤矿5301工作面新鲜暴露煤作为试验煤样,在实验室模拟高地温煤层降温开采环境,设置吸附温度为45℃,吸附平衡压力分别为0.3 MPa、0.5 MPa、0.8MPa的情况下,改变瓦斯解吸环境温度,进行颗粒煤的吸附-解吸试验。试验结果表明,同吸附温度和吸附平衡压力下,解吸环境温度越低,解吸速度越慢,同时间段内瓦斯解吸量越少。以吸附平衡压力0.3MPa、解吸温度25℃时的瓦斯解吸速度为基准,通过数据拟合,确定解吸温度T与解吸速度修正系数γ的关系,并以此推算出吸附温度为45℃时,不同解吸环境下,任意时刻累积瓦斯解吸量。     

煤体吸附解吸瓦斯规律及细观特征研究

煤体对瓦斯的吸附解吸特征对防止瓦斯事故以及煤层气抽采技术都具有重要的意义。对不同温度下的煤体吸附解吸规律做了量化研究,同时从细观角度对实验后的煤样做了渗透性分析,得到如下结论:煤体吸附和解吸瓦斯的过程均可分为3个不同的阶段,解吸率与温度呈对数关系变化;从20℃变化到80℃,孔隙率呈现先增后减的趋势;从煤体解吸率和渗透性的角度综合分析,认为60℃是煤体吸附解吸瓦斯的最佳温度。     

广西某铝母液中镓钒铝的偕胺肟螯合树脂吸附与解吸试验

广西某铝土矿浸出循环母液中富含镓、钒,为给镓的分离、回收工艺研究提供依据,研究了偕胺肟螯合树脂吸附镓、钒、铝的规律和盐酸解吸的规律。结果表明:①偕胺肟螯合树脂对镓具有较高选择性,对铝的吸附率非常低;吸附温度对树脂吸附镓、铝的影响较小,对吸附钒影响较大,钒吸附率随温度升高而增大;树脂对镓的吸附速率比钒快很多;该吸附过程符合准二级动力学模型和颗粒扩散模型;镓的最优吸附条件为吸附温度25℃,吸附时间60 min。②在25℃情况下较低浓度的盐酸就能高效、快速解吸偕胺肟螯合树脂吸附的镓、铝,且受解吸温度的影响较小,钒难以解吸;提高盐酸浓度和解吸温度,盐酸对钒的解吸率明显上升;镓的最优解吸条件为盐酸浓度1.0 mol/L,解吸温度25℃,解吸时间5 min。③由于偕胺肟螯合树脂对铝土矿浸出循环母液中镓和钒的吸附率较高,且钒解吸困难,影响树脂的再生和循环利用。为了高效、低成本分离、回收镓,需在树脂吸附镓之前先采用氢氧化钠沉淀并回收原液中的钒,以尽量降低溶液的钒含量。     

胡家河井田煤层气等压吸附/解吸特征研究

为了促进彬长矿区胡家河井田低煤阶煤层气开发实践,核定采收率,对4号煤层进行了样品采集、加工,完成了不同温度煤层气吸附/解吸试验,利用吸附/解吸结果绘制吸附等压线。结果表明:吸附量随着温度的升高而减小,低压阶段解吸滞后明显,高压阶段解吸过程与吸附过程可逆;CH_4吸附量与温度的关系可用二次函数表征,当温度大于临界温度(-82.6℃)时,最大吸附量沿抛物线分布;温度低于临界温度时,最大吸附量沿直线分布;最后得出CH_4吸附量的计算方法,解决了采收率核定时低阶煤含气量测试数据不准的问题。     

新型分子筛对海水中钙离子的脱除研究

采用静态吸附法研究了新型分子筛对海水中钙离子的吸附性能,结果表明,新型分子筛对钙离子有较好的吸附效果,其全交换容量可达254.85mmol/100g。考察了分子筛用量,吸附时间,溶液pH值和温度等因素对除钙效果的影响,确定了最佳操作条件为:分子筛用量2 g/100mL海水、吸附时间60 min、溶液pH值8.1、温度60℃。钙离子在分子筛上的吸附平衡符合Langmuir吸附等温方程,其吸附过程符合准一级吸附动力学方程。     

粉煤灰制备NaA型分子筛及其对铅离子的吸附性能研究

以粉煤灰为原料,采用碱熔-水热法合成NaA型分子筛。通过单因素试验探究了水热温度、水热时间、碱浓度、碱灰比对制备分子筛的影响,采用静态饱和吸水量和钙离子交换量对所制备分子筛的性能进行评价。结果表明:水热温度100 ℃、水热时间5 h、NaOH浓度2.73 mol/L、碱灰比2.8有利于NaA型分子筛的合成,其钙离子交换量最高可达374.63 mg/g。利用合成的NaA型分子筛对液相中的铅离子进行吸附研究,在分子筛投加量1 g/L、溶液pH值6.2、吸附温度25 ℃、吸附60 min时,吸附容量(Q_e)最高可达471.51 mg/g;分子筛的吸附等温线更加符合Langmuir等温线模型,饱和吸附容量(Q_m)可达580.18 mg/g。     

模拟酸雨对巯基化膨润土吸附Pb~(2+)的解吸研究

比较了巯基改性膨润土(TMB)和钙基膨润土(RB)对水溶液中铅的固定性能,考察了模拟酸雨pH值、离子强度、解吸温度和时间等条件对其解吸Pb~(2+)的影响。结果表明:在吸附条件一致的前提下,模拟酸雨p H值与铅的解吸量呈负相关性;模拟酸雨离子强度、解吸时间和解吸温度对钙基膨润土吸附铅的解吸影响较大,而对巯基改性膨润土吸附铅的解吸无影响,解吸率为0%。在20℃、30℃、40℃、50℃下,模拟酸雨对铅在巯基化膨润土上的平衡解吸量分别为39.52 mg/g、23.20 mg/g、21.74 mg/g和17.86 mg/g,表明该巯基改性膨润土对铅具有很强的固定能力。     

煤体吸附瓦斯过程温度场变化实验研究

为研究煤体吸附过程中温度的变化及分布情况,设计了瓦斯吸附解吸温度实验测量系统。系统主要包括3部分,即温度控制系统、瓦斯吸附解吸系统和多测点温度测量系统。通过自制的煤样,实验研究了在20℃的恒定温度下,不同煤样瓦斯吸附量以及瓦斯吸附过程温度变化情况;并且绘制温度场,通过温度场的测定,找到最适合单点测量吸附过程温度变化的点的位置,进一步拟合分析,提出了煤体吸附瓦斯过程中某点温度变化最大值和中心点处的关系式。     

煤的非均匀势阱分布及其对甲烷吸附/解吸的影响

为了研究煤的非均匀势阱分布及其对甲烷吸附/解吸过程的影响，在吸附科学和分子动力学理论基础上建立了非均匀势阱模型。该模型可以表征煤的吸附/解吸性能以及精确计算出煤体内不同势阱所对应的势阱数量。为了验证非均匀势阱模型对煤的吸附/解吸性能方面的表征能力的准确性，将其与Langmuir模型分别对甲烷吸附/解吸过程进行拟合，再将拟合数据和等温吸附线的相关系数分别进行比较。结果表明，非均匀势阱模型在表征煤体的吸附/解吸性能方面更优。在研究煤体内的势阱分布时，发现煤在不同温度压力下对甲烷的吸附/解吸过程中，煤体内的势阱分布出现明显差异。在分析煤的势阱规律时，发现在吸附阶段煤体内的势阱数量比解吸阶段多，但解吸过程中煤的平均势阱深度比吸附过程大。并且平均势阱深度随着煤阶的降低而降低。在吸附阶段势阱数量集中在某个势阱深度的范围内，但在解吸阶段势阱数量的分布相较而言就更分散。在同一温度下，势阱数量随着煤阶的降低而减少。从势阱分布来看，在相同温度下，高煤阶煤的势阱分布方差明显比低煤阶煤的势阱分布方差要大得多。温度上升会使得平均势阱深度随着温度的升高而下降。对于同一煤阶而言，温度的变化对5～15 kJ/mol内...     

China rare earth market review

正November 21~30,2014Due to weak demand from downstream industries,transactions of rare earth in Chinese domestic market were inactive.It was difficult to sell any rare earth products except for dysprosium oxide and terbium oxide.Suppliers lost confidence in recent market.Demand for rare earth products was soft.Consumers continued to take a wait-and-see attitude.Rare earth export market remained slow.     

Current situation and future trend of China rare earth luminescent materialindustry(continued)

<正>Developing ecological lighting source The world is facing the big problem of energy shortage today and the contradiction between economy development and environmental protection is worsened.Therefore,people are more likely to choose an ecological light source that is more energy efficient and environmental friendly.The choice provides great opportunity for the development of rare earth optical material industry in China.The concept of green lighting positions rare earth luminescent material as a leading player in illumination market.The light source of both rare earth luminescent lamp and LED lamp is ecological and energy saving.This is why     

Galaxy Magnets achieved the net profit of 34.02 million yuan in the first six months of 2014

正Galaxy Magnet announced its financial results for the first half of 2014 on August 14.For the first six months ended on 30 June 2014,Galaxy Magnet achieved operation income of RMB 182.3 million,up8.40% over the same period of 2013,and the net profit attributable to the shareholders of the listed company of 34.02 million yuan,increasing 35.49% over the same period of last year.Stable performance increase was led by development of new customers and application market of magnets.     

Rare Earth Application in Steel in China

<正>China has rich rare earth resources.Output of rare earth and steel in China ranks the top first in the world.However,there is still certain distance between the steel produced in China and developed countries from the point of varieties and quality.China still has to import some types of steel.Improving the quality should be emphasiZed in future development of steel industry in China.Rare earth can be used to upgrade traditional steel     

稀散金属产业的观察与思考

分析了近年来国内外稀散金属产业的生产、应用、资源与市场状况.铟锡氧化物靶材、砷化镓晶片、锗红外材料、铼高温合金和硒在电解锰及玻璃的应用等已成为稀散金属的主要应用领域.稀散金属的产量快速增长达到历史高位而导致了市场的失衡.以GaInP_2/GaAs/Ge,CIGS和CdTe为代表的非硅系太阳能电池是稀散金属的新兴应用领域,将给稀散金属带来日益增长的需求.     

China rare earth market review

正November 1~10,2014Chinese rare earth market was still inactive.Demand for rare earth products was weak.Consumers took a wait-and-see attitude for lower price.As it was an off season for rare earth products,it was expected that prices of rare earth could continue turbulence at the bottom in short terms.Due to a sharp drop,demand for rare earth from downstream recovered.Affected by new energy vehicles,wind powder and energy-efficient appliances,production of rare earth permanent     

China rare earth market review

正August 1~10,2014 There was some good news in rare earth industry recently.Restructuring plans of rare earth groups led by Baotou IronSteel Group and Xiamen Tungsten Group respectively have been approved by MIIT.And rare earth storage policy,which had been expected for a very long time,has been launched officially.Pushed by the good news,rare earth price started to rebound since August 5.Price of didymium oxide and dysprosium oxide rose about 1% to 2%,averagely.About 10% of     

China rare earth market review

正July 1~10,2014Due to weak demand from downstream industry and slow transactions,rare earth market remained weak and price of rare earth products continued to decline.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,     

New energy vehicle:an opportunity for rare earth magnets

<正>Extracted from Securities Guide 1.Popularity of new energy vehicles—an irresistible market trend1.1 Progress of new energy vehicles Chinese Premier Li Keqiang said recently on a visit to Xi'an BYD Autos that new energy vehicles,especially new energy bus,can lessen environment and noise pollution.He encouraged the use of new     

Brief news

正Corun invested another 50 million yuan in power battery for HEV Hunan Corun announced on 27 June that they had signed the cooperation agreement to jointly built Corun(Shaoxing)Autos Power Battery System Co.,Ltd.in Shaoxing Binhai New City.According to the announcement,total registered