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排序方式: 共有794条查询结果,搜索用时 31 毫秒
1.
借鉴英国经验完善中国土地产权流转 总被引:1,自引:0,他引:1
本文在简要介绍中、英两国土地产权制度和土地产权流转的基础上,分析了我国土地产权流转过程中出现的问题,如征地过程中的赔偿过低且不完善、国有土地拆迁补偿不公以及补偿的分配方式不公平等问题。由于英国在土地制度方面与中国的相似性,文章借鉴英国土地补偿中的补偿金与改善金相结合原则、土地使用权的租赁行为以及开发收益回馈社会的方法,为完善和健全我国的土地产权流转机制提出措施和建议。 相似文献
2.
武钢氧气公司在大型空分设备循环冷却水系统中,采用化学法和物理法进行水处理效果的实践探索,从原理和监测数据上进行了对比、分析研究,确认物理法具有高效除垢、防垢、杀菌灭藻、缓蚀以及净化等功能,可以取代化学法进行循环水处理。 相似文献
3.
An experimental investigation under cold condition was made to study the effects of some operating/design parameters and non-mechanical L valve configuration on the solid circulation rate in a 4.5 m tall, 0.15 m diameter circulating fluidized bed with riser flow rate varying from 1400 litres/min to 2000 litres/min and bed inventory from 15 kg to 25 kg of sand of average sizes 200 μm, 400 μm and 500 μm. Solid circulation rate was estimated by measuring velocity of sand particle travelling through a vertical Perspex tube section at the bottom of the return leg. It was found to be in the range of 2.8 to 12.3kg/m2s, 0.07 to 9.1kg/m2s and 0.12 to 2.23kg/m2s for sand sizes of 200 μm, 400 μm and 500 μm, respectively for a horizontal L valve. Two mathematical correlations have been developed from the experimental results to predict solid circulation rate as a function of riser flow rate, aeration flow rate, total bed inventory and particle size used. 相似文献
4.
不停车清洗预膜在2号高炉净循环水系统的应用 总被引:1,自引:0,他引:1
循环冷却水系统长期运行过程中,由于多种因素影响,管道、阀门、水泵等设备产生结垢和腐蚀,为使水系统保持长期正常运行,减缓腐蚀结垢速度,需投加杀菌剂和阻垢缓蚀剂,2a进行一次清洗和预膜。主要介绍了2号高炉净循环水系统不停车清洗预膜的步骤、效果,并推荐在工况相似循环水系统中参考应用。 相似文献
5.
Biomass pyrolysis in a circulating fluid bed reactor for the production of fuels and chemicals 总被引:3,自引:0,他引:3
An approach for biomass flash pyrolysis in a circulating fluid bed (CFB) reactor with continuous solids regeneration is described in this study. The unit is capable of performing conventional and catalytic biomass pyrolysis with the proper solid selection. The production of improved quality liquid products in a direct step through catalytic pyrolysis is investigated in this work. Both conventional and catalytic biomass pyrolysis can be effectively performed in this CFB unit. Flash pyrolysis conditions were achieved and liquid product yields of ∼70 wt% (on biomass feed) were obtained. The effect of specific operating variables including the type of inorganic solid material and the solid/biomass ratio was established on the final liquid product quality and yield. Solid materials considered included silica sand, a commercial fluid catalytic cracking catalyst and a ZSM-5 additive. Catalytic biomass pyrolysis generally leads to the production of additional water, coke and gases compared to conventional pyrolysis. However, the obtained liquid product quality and composition is improved. 相似文献
6.
干熄焦循环气体成分的分析和控制 总被引:2,自引:0,他引:2
分析了干熄焦循环气体成分,针对可燃气体成分爆炸的极限值,控制及制定循环气体成分的指标。 相似文献
7.
A fractal approach is adopted to describe the dynamic behavior of a circulating fluidized bed. Two times series, differential pressure fluctuations along the riser height and solids momentum fluctuations along the radial direction, are measured and analyzed in terms of fractal dimensions. The influences of operating conditions and axial/radial positions on the fractal dimension are discussed. Attempts are also made to interpret the flow structure in the bed in terms of the fractal dimension. It is found that fractal analysis can provide a useful tool for understanding the characteristics of gas-solids flow in circulating fluidized beds. 相似文献
8.
Solid circulation characteristics in an internally circulating fluidized bed with orifice-type draft tube 总被引:1,自引:0,他引:1
Sang Done Kim Yo Han Kim Seon Ah Roh Dong Hyun Lee 《Korean Journal of Chemical Engineering》2002,19(5):911-916
Effects of superficial gas velocities to a draft tube, to an annulus section and particle size on the solid circulation rate
(G,) have been determined in an internally circulating fluidized bed (0.28 m I.D. × 2m high) with an orifice type draft tube.
The solid circulation rate from the draft tube to an annulus section increases with increasing gas velocities to the draft
tube(U
d
) and annulus section (Ua) and consequent increase in pressure drop across the orifice (ΔPor). However, the values ofG
s
decrease by 7–21% with increasing particle size from 86 to 288 μm. The pressure drop across the orifice increases with increasingU
d
andU
a
. However, ΔPor decreases by 5–23% with increasing particle size. To predictG
s
in an internally circulating fluidized bed, a correlation is proposed as a function of ΔPor
This paper is dedicated to Professor Dong Sup Doh on the occasion of his retirement Korea University. 相似文献
9.
An axial dispersion of gas in a circulating fluidized bed was investigated in a fluidized bed of 4.0 cm I.D. and 279 cm in
height. The axial dispersion coefficient of gas was determined by the stimulus-response method of trace gas of CO2. The employed particles were 0.069 mm and 0.147 mm silica-sand. The results showed that axial dispersion coefficients were
increased with gas velocity and solid circulation rates as well as suspension density. The experimentally determined axial
dispersion coefficients in this study were in the range of 1.0-3.5 m2/s. 相似文献
10.
陆建刚 《化学工业与工程技术》1995,16(4):9-12
开展了以KCI、(NH_4)_2SO_4为原料制备K_2SO_4的研究工作。确定了循环比、洗涤条件与反应时间。K_2总转化率达75%,产品收率约97%;产品中Cl含量为0.5%~1.5%。 相似文献