浅谈热泵技术在兖矿集团的应用

通过对兖矿集团所属煤矿供暖小区的现状以及能耗进行调查、分析,本文就如何采用先进的热泵技术,对矿区燃煤小锅炉进行节能技术改造展开探讨,对类似节能改造有较高借鉴作用。     

Influence of H2S and NH3 on biogas dry reforming using Ni catalyst: a study on single and synergetic effect

● NH₃ in biogas had a slight inhibitory effect on dry reforming. ● Coexistence of H₂S and NH₃ led to faster decline of biogas conversion. ● Regeneration was effective for catalysts deactivated under synergetic effect. Biogas is a renewable biomass energy source mainly composed of CH₄ and CO₂. Dry reforming is a promising technology for the high-value utilization of biogas. Some impurity gases in biogas can not be completely removed after pretreatment, which may affect the performance of dry reforming. In this study, the influence of typical impurities H₂S and NH₃ on dry reforming was studied using Ni/MgO catalyst. The results showed that low concentration of H₂S in biogas could cause serious deactivation of catalyst. Characterization results including EDS, XPS and TOF-SIMS confirmed the adsorption of sulfur on the catalyst surface, which was the cause of catalyst poisoning. We used air calcination method to regenerate the sulfur-poisoned catalysts and found that the regeneration temperature higher than 500 °C could help catalyst recover the original activity. NH₃ in the concentration range of 50–10000 ppm showed a slight inhibitory effect on biogas dry reforming. The decline rate of biogas conversion efficiency increased with the increase of NH₃ concentration. This was related to the reduction of oxygen activity on catalyst surface caused by NH₃. The synergetic effect of H₂S and NH₃ in biogas was investigated. The results showed that biogas conversion decreased faster under the coexistence of H₂S and NH₃ than under the effect of H₂S alone, so as the surface oxygen activity of catalyst. Air calcination regeneration could also recover the activity of the deactivated catalyst under the synergetic effect of H₂S and NH₃.     

Steam reforming of glycerol for syngas generation under cold plasma conditions: A DFT study

Density functional theory (DFT) has been used to investigate the reaction pathways with steam reforming of glycerol under cold plasma conditions. Total energies, energy barriers, and reaction enthalpies at 298.15 K have been calculated at the GGA/PW91/DNP level. The calculation shows that, with the presence of steam, the energy barrier of glycerol conversion is reduced and the conversion from glycerol to H₂ and CO is promoted under cold plasma conditions. The formation of syngas was through a multi-step pathway via the conversion of OHCH₂CHOH, CH₂OH, CH₂O, HCO,·and CH₃, while the recombination of H generated extra H₂. The synthesis of hydrocarbons are from the recombination of·CH₃,·CH₂, and·CH, which could be primarily generated through glycerol dissociation. The structure of glycerol anion was also studied in this work, and it was less stable than the neutral molecule. The route for the formation of OHCH₂CHOH·and CH₂OH·from glycerol anion is thermodynamically favorable.     

骨炭对水中不同形态Sb吸附和解吸的影响

采用骨炭作为吸附剂，研究其在不同骨炭用量、pH值和温度条件下对水中Sb（Ⅲ）和Sb（Ⅴ）吸附和解吸的影响。结果表明，骨炭对Sb（Ⅲ）的吸附效果远好于Sb（Ⅴ），在0.2~8.0 mmol/L的Sb（Ⅲ）和Sb（Ⅴ）浓度下，骨炭对这2种形态Sb的去除率分别为46.1%~78.6%和9.6%~31.7%。采用Langmuir方程和Freundlich方程均可以很好地拟合骨炭对Sb（Ⅲ）和Sb（Ⅴ）的吸附，Sb（Ⅲ）和Sb（Ⅴ）的最大吸附容量分别为110.1034 mg/g和17.4167 mg/g。骨炭对Sb（Ⅲ）的解吸也大于对Sb（Ⅴ）的解吸。骨炭对Sb（Ⅲ）和Sb（Ⅴ）的吸附受不同骨炭用量、pH值和温度影响。     

骨炭修复重金属污染土壤和降低基因毒性的研究

采用分级提取的方法研究了施加骨炭对污染土壤重金属的固定效果,结果表明,土壤施加10 mg·kg^-1骨炭后水溶态、交换态、碳酸盐结合态和铁锰氧化物结合态Pb的浓度都显著下降;而加入骨炭后土壤有机结合态Pb的浓度显著上升,表明骨炭可以吸附、固定土壤中的Pb,改变Pb的化学形态,降低Pb的生物可利用性.加入骨炭后土壤中水溶态和交换态Cd的浓度都显著下降,残渣态Cd的浓度明显上升.骨炭处理对土壤中Cu化学形态的影响和Pb相似,表明骨炭可以吸附固定土壤中的Cu.骨炭处理对Zn也有一定的固定效果,降低了土壤中水溶态的Zn.采用植物彗星实验研究了施加骨炭对土壤基因毒性的影响,表明加入骨炭后减轻了污染土壤对洋葱根尖细胞的DNA的损伤,降低了土壤污染对植物的基因毒性.生物评价和化学评价的结果均表明骨炭是重金属污染土壤的有效修复剂,能有效降低污染土壤中重金属的生物有效性和对植物的毒性.     

污水污泥裂解目标产物及残焦促进植物生长的研究

研究了污水污泥的低温裂解特性,考察了裂解终温和干燥到一定程度后污泥含水率对裂解产物分布及产物性质的影响,并分析了裂解产物中最合适的目标产物形式.经过分析比较,最终确定以污泥裂解残焦为目标产物并通过与普通土壤混拌进行了栽种大蒜和测试大蒜重金属浓度水平的实验,并考察残焦中重金属向植物迁移的情况.结果表明,干燥到一定程度的污水污泥在550℃下裂解时残焦的产率在40%以上,其中灰分含量在60%～65%之间,富含氮、 磷、 钾.该残焦中重金属含量符合有关土地使用规定,能明显促进大蒜植株的生长,实验组平均株高比普通组高出3～4　cm;但是快速生长的大蒜植株中重金属浓度略有增加.研究表明残焦是合适的污水污泥裂解目标产物,具有土地使用的前景,能够用于促进非食用目的的植物的生长.     

基于保护的瓷窑型遗址绿化改造研究——以长沙铜官窑遗址为例

瓷窑型遗址由于其埋藏浅、需要恒温恒湿等特点,对绿化的要求与其它遗址不尽相同。基于保护为主的绿化改造是瓷窑型遗址保护的重要内容。文章以长沙铜官窑遗址为例,在分析了长沙铜官窑遗址的植被组成、绿化现状以及现有植被对遗址保护的利弊基础上,提出了基于保护为主的绿化改造总体设想、主要对策措施和技术模式,希望为中国瓷窑型遗址的绿化改造提供借鉴。     

富含甲烷的可再生资源重整制氢的研究进展

将富含甲烷气体的可再生资源用于重整制氢不仅可以节省天然气等不可再生资源,同时可以减少CH4、CO2等温室气体的排放,因此具有节约能源和保护环境两方面的重大意义。文章分析了可再生资源的富含甲烷气体的种类及其特性,以及该种可再生资源作为重整制氢原材料的优势和可能转化途径,并综述了国内外在这一领域近几年的研究工作,最后对富含甲烷气体的可再生资源作为制氢原料的前景进行了展望。     

包装废弃物添加脱氯半焦制备SRF的热解及动力学特性

利用热重红外分析仪(TG-FTIR)对包装废弃物添加了4种不同比例脱氯半焦制备而成的固体衍生燃料(SRF)的热解特性及热反应动力学进行了研究分析.研究发现,4种燃料热解过程主要包括4个阶段,其中300~400℃和400~500℃为两个主要失重阶段.前一阶段,SRF-1失重显著高于SRF-2、SRF-3和SRF-4,而后一阶段失重分别呈2、3、4倍增加.4种燃料热解残余量的顺序为SRF-4SRF-3SRF-2SRF-1,即添加了脱氯半焦的燃料热解程度越高.FTIR分析表明,添加了脱氯半焦的SRF燃料第三失重峰处不产生氯代烃.随脱氯半焦添加量的增加,第二失重峰CO2产生的浓度减少;第三失重峰CH4析出浓度增加;第四失重峰CO2析出的浓度增加.采用DEAM分布活化能法得到,转化率α0.3时,SRF-2和SRF-3的活化能均高于SRF-1的活化能,0.3α0.9时(α为0.6时除外),SRF-2、SRF-3和SRF-4 3种燃料的活化能低于SRF-1,且SRF-1的活化能呈升高的趋势,而其他3种燃料呈相反趋势.脱氯半焦的添加有利于SRF燃料的热解.     

用于燃料电池的甲醇水蒸气重整反应制氢的研究

研究了甲醇水蒸气重整制氢反应过程中各种因素对Cu／ZnO／Al2O3催化剂的活性和选择性的影响。结果表明：Cu／Zn比为2．0的催化剂在250℃反应时，催化剂效果较好，最合适反应条件是：压力0．1MPa，温度250℃，n(H2O)：n(CH3OH)=1．0-1．2，液体流速0．1mL／min。在Cu／ZnO／Al2O3)，催化剂上，甲醇水蒸气重整、甲醇分解和水气转换反应随反应条件的不同而发生相互抑制或促进作用。