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181.
稻谷壳流化床的燃烧特性   总被引:5,自引:1,他引:4  
介绍了稻谷壳的物理化学特性及热重试验结果,与煤燃特性进行对比,阐述了稻谷燃烧过程中,挥发分与焦炭分阶燃烧的概念;并通过燃烧试验提出了独特的以纯稻谷壳流态化燃烧方式为主的组合燃烧方式,为纯稻谷壳流态化燃烧锅炉设计和运行提供了理论依据。  相似文献   
182.
生物质高能洁净燃料   总被引:1,自引:0,他引:1  
朱锡锋  郭庆祥  朱清时 《科学》2002,54(4):20-22
地球生态系统是由环境和生物共同组成的一个完整的封闭循环系统.在这个系统中碳和能量是两个最重要的循环载体,碳是构成一切有机体必不可少的主要元素之一,约占生命物质总量的25%,能量则是维持自然界一切活动的动力源泉.由于碳和能量的不断循环并保持平衡,才使得地球生态系统不断延续并充满活力.  相似文献   
183.
论述了流化床电炉的热平衡问题。根据该炉种特殊的工艺特征提出了独有的计算方法和计算公式,为进一步开发、完善该炉种提供了科学的设计依据和可靠的技术数据。  相似文献   
184.
ATP content and biomass activity in sequential anaerobic/aerobic reactors   总被引:1,自引:0,他引:1  
Specific ATP content of volatile solids was measured to characterize the sludge activity in a sequential anaerobic/aerobic wastewater treatment system, with an upflow anaerobic sludge blanket (UASB) reactor and a three-phase aerobic fluidized bed (AFB) reactor. The wastewater COD level was 2000-3000 mg/L in simulation of real textile wastewater. The ATP content and the specific ATP contents of volatile solids at different heights of the UASB reactor and those of the suspended and immobilized biomass in the AFB reactor were measured. In the UASB reactor, the maximum value of specific ATP (0.85 mg ATP/g VS) was obtained at a hydraulic retention time (HRT) 7.14 h in the blanket solution. In the AFB reactor, the specific ATP content of suspended biomass was higher than that of immobilized biomass and increased with hydraulic retention time reaching a maximum value of 1.6 mg ATP/g VS at hydraulic retention time 4.35 h. The ATP content of anaerobes in the UASB effluent declined rapidly under aerobic conditions following a 2nd-order kinetic model.  相似文献   
185.
Great efforts have been made to resolve the serious environmental pollution and inevitable declining of energy resources. A review of Chinese fuel reserves and engine technology showed that compressed natural gas (CNG)/diesel dual fuel engine (DFE) was one of the best solutions for the above problems at present. In order to study and improve the emission performance of CNG/diesel DFE, an emission model for DFE based on radial basis function (RBF) neural network was developed which was a black-box input-output training data model not require priori knowledge. The RBF centers and the connected weights could be selected automatically according to the distribution of the training data in input-output space and the given approximating error. Studies showed that the predicted results accorded well with the experimental data over a large range of operating conditions from low load to high load. The developed emissions model based on the RBF neural network could be used to successfully predict and optimize the emissions performance of DFE. And the effect of the DFE main performance parameters, such as rotation speed, load, pilot quantity and injection timing, were also predicted by means of this model. In resum6, an emission prediction model for CNG/diesel DFE based on RBF neural network was built for analyzing the effect of the main performance parameters on the CO, NOx emissions of DFE. The predicted results agreed quite well with the traditional emissions model, which indicated that the model had certain application value, although it still has some limitations, because of its high dependence on the quantity of the experimental sample data.  相似文献   
186.
介绍了所设计的新型多燃料油炉的基本结构和主要性能 .在该多燃料油炉中 ,应用旋焰燃烧理论解决了油炉在低温环境和高海拔缺氧环境中点火困难的问题 ,并应用安全阀技术解决了油炉“回火”和“非正常熄火”等关键问题  相似文献   
187.
生物液体燃料——燃料酒精   总被引:1,自引:0,他引:1       下载免费PDF全文
江宁 《自然杂志》2007,29(1):30-30
燃料酒精作为可再生能源不会枯竭,并且不会引起温室效应。微生物发酵糖可以生产酒精。目前在工业生产中用于发酵产酒精的微生物主要是酿酒酵母和运动发酵单胞菌。包括秸秆在内的含有糖类物质的生物质都可能作为酒精发酵的原料,大分子物质的利用需先经过酶的降解。生物酒精作为石油的替代物,其产业链还在继续延伸。  相似文献   
188.
《中国科技成果》2007,(19):44-45
“十五”国家科技攻关计划“锥形流化床生物质气化技术”课题(编号:2001BA40380301)针对目前国内生物质气化发电、供热、供气存在的原料适应范围窄、燃气焦油含量高、自动化程度低、适用松散型物料的气化发电设备和系统等问题,开发锥形流化床生物质气化发电供热、供气机技术产业化为目标,研制生物质气化装置与气体发电机组成的系列生物质气化发电系统;  相似文献   
189.
周昌  胡真  张晓 《科技信息》2007,(28):33-35
对ZS1110T直喷式柴油机燃用生物柴油进行了试验研究.结果表明:在不对原机结构作任何改动的情况下,燃用生物柴油的有效功率比柴油的有效功率大约低10.2%,生物柴油的燃油消耗率比柴油大约高出13.1%.在排放方面,在原机上燃用生物柴油可以降低CO、HC、碳烟排放,由于生物柴油中含氧量高,所以NOx排放比柴油略有增加.从试验中的排放效果来看,生物柴油是柴油机理想的低排放代用燃料.  相似文献   
190.
Auto-ignition characteristics of high-pressure diesel spray in the controllable active thermo-atmos-phere (CATA) were studied with a high-speed camera video system. Multi-point autoignition phe-nomenon of diesel spray in the CATA was observed and the influence factors of the autoignition were analyzed. The stabilization mechanisms of the spray flame in different coflow temperatures were also discussed. The stabilization of the flames was controlled by different factors: autoignition phenomenon in low coflow temperature and flame spread in high coflow temperature. The test results also show that the autoignition delay depends strongly on the coflow temperature and has nonlinear relationship with the temperature. Autoignition delay decreases by almost 10 ms from 16.9 to 7.1 ms when the coflow temperature increases from 996 to 1048 K and only 4 ms from 1048 to 1101 K. The injection parameters in terms of nozzle diameter, injection pressure and pump speed, have some effects on autoignition delay while these effects depend on the coflow temperature. The significant effect lies in low coflow temperature. The injection parameters influence the autoignition delay because it can shorten the physical delay by improving the spray quality and enlarging the spray angle or penetration rate to im-prove mixture quality.  相似文献   
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