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1.
部分气化联合循环发电系统热力性能分析   总被引:1,自引:0,他引:1  
针对增压部分气化2种增压流化床(PFB)锅炉半焦燃烧和2种常压流化床(CFB)半焦燃烧的先进增压流化床燃烧联合循环(APFBC-CC)方案,进行了系统热力性能计算, 分析比较了主要参数对系统性能的影响. 结果表明,将PFB锅炉高温烟气引入部分气化炉的方案一避开了高温烟气过滤式除尘器, 但降低了煤气热值和系统效率; 方案二则可获得较高的系统效率, 然而高温过滤式除尘器目前技术上有一定困难, 需降温运行; 方案三、四采用CFB锅炉半焦燃烧系统, 其中方案四采用气化空气/蒸汽预热方法, 不仅可获得较高的煤气热值, 而且可提高系统效率.  相似文献   

2.
基于质子交换膜燃料电池的天然气微型热电联产系统的核心单元是重整制氢反应器.设计研发了一种集蒸汽发生和天然气水蒸汽氧化重整于一体的制氢反应器,实验测试了典型工况下反应器的性能,以及操作条件(水碳比、空碳比、空速)对反应器性能的影响.在典型操作条件下,反应器平均床层温度为630℃,反应器出口合成气的物质的量组成为H。40.61%、N。37.63%、CO5.56%、CH43.62%、C0212.58%,甲烷的转化率为92.56%,反应器能量利用效率88.3%.实验表明这种制氢反应器可用干微型天蚨气执由群声桑缔  相似文献   

3.
This work investigates the effects of exhaust gas recirculation (EGR) and operation parameters including engine speed, equivalence ratio, coolant-out temperature, and intake charge temperature on the basic characteristics of a single-cylinder homogeneous charge compression ignition (HCCI) engine powered with reformulated iso-octane fuels. The running range of iso-octane HCCI engine can be expanded to lower temperature and more load by adding di-tertiary butyl peroxide (DTBP) in the fuel. The combustion timing advances with the increase of DTBP concentrations, coolant temperature and equivalence ratio. The effects of EGR on the combustion and emissions are remarkable when the EGR rate is higher than 25%, and the combustion phase is sharply postponed and the UHC and CO emissions deteriorate. The intake charge temperature has a moderate effect on combustion and emissions when it is lower than 35°C; but the combustion timing advances, the combustion duration shortens, and sometimes it leads to knock combustion when the intake charge temperature increases to above 35°C.  相似文献   

4.
应用XRD和催化活性评价手段,考察了助剂对CH_4与CO_2重整制合成气的负载型Ni催化剂的重整活性和其抗积炭性能的影响。实验结果表明,NiO在Υ-Al_2O_3表面上最大分散量随MgO、La_2O_3助剂的添加不同程度地增大,助剂能影响负载型Ni催化剂的催化性能,MgO、La_2O_3的添加对改善Ni催化剂的重整活性和抗积炭性能有明显效果,并与助剂的种类、添加次序有关。La_2O_3助剂的突出作用表现在维持Ni为低价还原态和促进CO_2转化等方面。  相似文献   

5.
变频技术是变频空调的核心技术,它不仅能降低噪声,还能提高制冷/热效果和舒适度.而使其拥有较高的可靠性和较低的功耗是由于在变频技术中采用了模块化的功率器件IPM智能功率模块.IPM不但能减少工作噪声,还可以提高系统的可靠性及控制效率.新一代的IPM还改进内部的寄生结构,在低正向压降、高开关速度和宽安全工作区方面进行优化设计,因此在空调和其它的家用电器中得到更广泛的应用.  相似文献   

6.
利用XRD,TPR和活性评价等手段,研究了NiO/γ-Al2O3催化剂的制备方法对CH4与CO2转化制合成气催化活性的影响.在本实验条件下,采用浸渍法和焙烧温度为400℃制备的NiO/γAl2O3(ω=0.113)催化剂,在反应温度为750℃和空速为2500h-1下,对CH4和CO2重整反应会显示良好的催化活性.本文还对催化剂抗积炭性能作初步讨论.  相似文献   

7.
Pulverized coal reburning, ammonia injection and advanced reburning in a pilot scale drop tube furnace were investigated. Premix of petroleum gas, air and NH3 were burned in a porous gas burner to generate the needed flue gas. Four kinds of pulverized coal were fed as reburning fuel at constant rate of 1g/min. The coal reburning process parameters including 15%~25% reburn heat input, temperature range from 1100 ℃ to 1400 ℃ and also the carbon in fly ash, coal fineness, reburn zone stoichiometric ratio, etc. were investigated. On the condition of 25% reburn heat input, maximum of 47% NO reduction with Yanzhou coal was obtained by pure coal reburning. Optimal temperature for reburning is about 1300 ℃ and fuel-rich stoichiometric ratio is essential; coal fineness can slightly enhance the reburning ability. The temperature window for ammonia injection is about 700 ℃~1100 ℃. CO can improve the NH3 ability at lower temperature. During advanced reburning, 72.9% NO reduction was measured. To achieve more than 70% NO reduction, Selective Non-catalytic NOx Reduction (SNCR) should need NH3/NO stoichiometric ratio larger than 5, while advanced reburning only uses common dose of ammonia as in conventional SNCR technology. Mechanism study shows the oxidization of CO can improve the decomposition of H2O, which will rich the radical pools igniting the whole reactions at lower temperatures.  相似文献   

8.
Indoor air quality and thermal comfort are important features of indoor environment, In this paper, a numerical simulation based on the k-ε model of CFD is used to analyze factors such as loading, exterior-protected construction, blowing-in rate that play an important role in the temperature field and airflow field of the displacement ventilation system. Exterior-protected construction has little influence on indoor temperature distribution of displacement ventilation systems and the influence is limited only in a small area near the external wall when the indoor heat source is the main cooling load. The height of a room has little influence on indoor temperature field, and the temperature gradient of active region is basically unchanged. In the system combined with a displacement ventilation system and a cooling system, the height also has little influence. When the cooling load is high,the indoor heat source creates a strong convective plume, which will make the average indoor air age lower, the ventilation efficiency higher and the elimination of pollutant easier. Air supply rate plays an important role in displacement ventilation systems. The increase of air supply rate that can be realized by increasing the air supply velocity and enlarging the area of air inlet will increase the mass capability of the system and diminish the vertical temperature gradient. From the comparison between simulations and experiments, it is concluded that this simulation are creditable.  相似文献   

9.
2-苯乙醇(2-PEA)是一种具有玫瑰花香的芳香醇,广泛应用于医药和食品工业。生物催化合成过程中,其原位萃取具有重要的意义。本研究设计合成了1-N,N-二乙基乙酰胺基-3-乙基咪唑双三氟甲基磺酰亚胺盐([EDCmim]NTf2)和1-丁基-3-甲基咪唑六氟磷酸盐([BMIM]PF6)两种离子液体,系统研究了其对2-苯乙醇萃取过程。考察了影响萃取性能的主要因素,如初始浓度、体系温度、相比等。结果表明,30 min内均可达到萃取平衡;2-苯乙醇的萃取不受转速的影响;随着相比的增加,萃取率也随之增加;随着温度的升高,萃取率随之降低;随着离子液体使用次数的增加,2-苯乙醇的萃取率也逐渐降低。  相似文献   

10.
针对转炉冶炼轴承钢终点高碳、低磷、保温度的工艺要求,优化转炉冶炼工艺,提高转炉终点碳含量,保证终点磷和终点温度控制稳定,实现提高钢水质量,降低生产成本等要求。  相似文献   

11.
INTRODUCTION Located in subtropical monsoon area, the redsoil region in western Zhejiang, China, is one of themain cash crop production bases of this province. Dueto the climate, the temporal and spatial distribution ofrainfall varies greatly in this region. Only 15 percentof rainfall occurs in summer (July, August and Sep-tember), while about 60 percent of rainfall occurs inspring (from March to June). The region suffersdrought in summer and waterlogging in spring. Theparent ma…  相似文献   

12.
通过分析漂白粉纯样、受潮样品和含有氧化铁的样品受热条件下发生的热解过程,发现水分和氧化铁的存在会促进漂白粉的受热分解.通过自行设计的漂白粉遇水受潮自热实验装置模拟漂白粉在长时间暴露于潮湿空气中的体系热聚集效应.发现在潮湿空气下,漂白能够聚集热量,导致内部温度的升高.从热解动力学的角度证实了氧化铁和水的存在降低了漂白粉分解时的活化能而导致反应速率增大.  相似文献   

13.
增压喷动流化床中煤半气化数值模拟   总被引:1,自引:0,他引:1  
本文对增压喷动流化床中煤半气化进行了模拟 ,在模型中考虑了增压喷动流化床的物理特性、化学反应、能量平衡 ,对床压、床温、空煤比 ,汽煤比对生成煤气成分的影响进行了研究 .计算结果表明增压喷动流化床中床压、床温对煤的半气化影响较强  相似文献   

14.
The high temperature heat pump and desiccant wheel(HTHPDW) system can make full use of heat released from the condenser of heat pump for DW regeneration without additional heat. In this study, DW operation in the HTHPDW system was investigated experimentally, and the optimization analysis of HTHPDW system was carried out. The performance of DW had influence on the dehumidification(evaluated by dehumidification and regeneration effectiveness) and cooling load(evaluated by thermal and adiabatic effectiveness). The results show that the enthalpy increase occurred in all the experiments. Compared to the isosteric heat, heat accumulation in the desiccant and matrix material and heat leakage from regeneration side to process side have greater influence on the adiabatic effectiveness. Higher regeneration temperature leads to lower adiabatic effectiveness that increases more cooling load of the system. When the regeneration temperature is 63℃, the maximal dehumidification effectiveness is 35.4% and the satisfied adiabatic effectiveness is 88%, which contributes to the optimal balance between dehumidification and cooling.  相似文献   

15.
1 Introduction X-ray emission from laser-produced plasma is notonly of considerable interest for inertial confinementfusion application,but is also of i mportance to a num-ber of other applications[1-3].Thelaser-plasma interac-tion can be efficient , bright , and versatile source ofX-rays . X-ray emission shows a remarkable variation withlaser wavelength . Shorter wavelengths are more effi-cient for producing quasi-thermal plasma emission.Longer wavelength laser-plasma interactions have pro-d…  相似文献   

16.
引入一种新的预测垃圾产量的方法——组合预测方法,该法能够综合利用不同预测方法提供的信息提高预测精度。结合厦门市1996~2008年的垃圾产量,分析不同预测方法的预测精度,并预测5年后的垃圾产量。通过研究发现:单一预测模型中,线性回归法和年增长率法的预测结果偏小,误差较大,灰色理论GM(1,1)的预测结果偏大,误差较小,基本在10%以内;组合预测模型的预测精度高于单一预测模型;厦门市城市生活垃圾年平均增长率约为10%,低于国民生产总值和社会消费品零售总额年平均增长率,高于城镇居民消费性支出年平均增长率。  相似文献   

17.
以梅州文化公园景观湖的底泥为研究对象,考察了水体扰动、上覆水初始磷浓度、水温、溶解氧浓度、铝盐浓度等因素对底泥磷释放的影响.结果表明,水体扰动、水温升高会增加底泥中磷的释放量;水中的溶解氧对底泥释磷有显著影响,较高的溶解氧浓度抑制磷的释放,较低的溶解氧则有利于底泥中磷释放;水中铝盐浓度大于1.00 mg/L时能够抑制底泥中磷的释放.底泥释磷存在一个临界浓度(0.55mg/L),当上覆水中磷浓度高于0.55mg/L时,底泥从水中吸附磷;当水中的磷低于0.55mg/L时,底泥向水中释放磷.  相似文献   

18.
通过对空气源热泵热水器的性能进行实验研究,考察了空气的相对湿度对其性能的影响。实验结果表明:空气的相对湿度对蒸发压力、COP和吸气温度等性能有一定的影响;相对湿度的增大会导致蒸发器表面冷凝水增多,有效润湿面积增大,空气侧与制冷剂侧换热系数增加,最终导致蒸发器潜热换热量增加,从而强化了传热。  相似文献   

19.
为确定残积土表面蒸发强度影响因素的敏感程度及其模型,以2种花岗岩残积土为例,采用自制室内蒸发试验,分析了温度、风速、太阳辐射、空气湿度、压实度、含水率对蒸发强度的影响规律,并标定了E0—θ模型的参数.结果表明,土体在高温(40℃)条件下蒸发强度约为低温(5℃)条件下的10-20倍;受太阳辐射时蒸发强度约为相同温度下不受太阳辐射时的1.5~2倍;有风条件下土表蒸发强度约为无风状态下的2~4倍;空气湿度越低蒸发强度越高;随着土壤压实度的增加,土壤蒸发强度逐渐减小,但其影响较小;土体蒸发强度随含水率降低呈减小趋势,并可近似为直线关系.因此,在确定土袁蒸发强度时应重点考虑温度、风速、空气湿度、太阳辐射、含水率的影响;E0-θ蒸发模型适用于花岗岩残积土的蒸发强度模型,相关指数均在0.9以上.  相似文献   

20.
介绍了一种自行研制的空调表冷器热工性能测试系统,该系统是通过对实验室现有空气调节处理过程实验台进行改造制得。在压缩机和节流阀之间装设套管式蒸发器,制得冷冻水,经水泵送入表冷器中,与空气进行换热后重新返回套管式蒸发器中。通过温控器实现表冷器入口冷冻水温度的控制,表冷器进出口冷冻水温通过布置热电偶进行测量,冷冻水流量通过转子流量计进行测量,利用原有干湿球温度计测量空气进出口干湿球温度,进而在不同工况下实现表冷器析湿系数、热交换效率、接触系数和换热量的测试。依据测试结果分析风量、风速、冷冻水流量对表冷器热工性能的影响。  相似文献   

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