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81.
Using discrete heat sources such as a radiator or a gas heater, a large amount of heated air is accumulated under the ceiling surface where it is usually far enough from the occupancy zone. The idea of transferring this heated air into the occupancy zone has been the subject of the present study. A full length-scale model of a compartment was constructed and equipped with a radiator and an air circulating mechanism. Temperature distribution on the symmetry plane was specified for the two cases of usual heating and heating with air circulation. Heat loss from the surfaces of the enclosure was also determined using thermal maps of both the internal and the external surfaces of the enclosure. In order to examine the effect of circulating air on the thermal energy saving quantitatively, a numerical model was developed and validated using experimental results. The input heat rate of the enclosure was compared for the two cases of usual heating and heating with air circulation considering different heights for a typical heating space. Based on the results, having the same mean air temperature within the occupancy zone, the input heat rate of a compartment could be moderated using circulating air criterion. 相似文献
82.
In this paper, a 65 t/h oil shale-fired circulating fluidized bed (CFB) boiler was put into commercial operation in Huadian of China in 1996 and industrial hot experiment was done for studying the flow structure and combustion characteristic of CFB dilute phase regime. Flow structure and solid flux of dilute phase regime were investigated along both vertical direction and horizontal direction under different boiler loads. Particle-size distribution and carbon content of oil shale combustion residues were obtained. Experimental investigation shows that SO2 concentration decreases with increasing the furnace height, and NOX emission can be reduced by adopting staged combustion technology, low-temperature combustion and circulating combustion. Experimental results are valuable for adjusting the 65 t/h boiler and designing large-scale oil shale-fired CFB boiler. At the same time, the experiment lays a foundation for modeling the flow structure, combustion, heat transfer and abrasion of oil shale-fired CFB dilute phase regime. 相似文献
83.
84.
通过宝钢1,2期干熄焦的设计,建设和生产实足,结合前苏联和日本的情况,就干熄焦设计中有关主要设备的造反进行了研讨,提供了选择的依据。 相似文献
85.
气固下行流化床反应器:Ⅰ下行管反应器的发展及其应用 总被引:9,自引:0,他引:9
和上行提升管反应器相比,敢固下行流化床反应器由于具有气固停留时间短,气固径向分布均匀,返混小等显著优点,因而在化工,石油,石油化工,能源等许多领域具有潜在的应用的前景,被誉为是21世纪取代提升管反应器的一种新型高效反应器。 相似文献
86.
87.
具有自主知识产权的棒材强力浊环水冷却设备的问世,为QTB工艺的实施提供了物质基础。其强力冷却机理是由于冷却介质中引入可固体颗粒的结果,浊环水中的杂质导致了冷却水气化率的提高和气泡寿命的缩短。文中也介绍了设备的主要结构、特点和应用效果。 相似文献
88.
Synthol reactor technology development 总被引:3,自引:0,他引:3
Since Sasol introduced the Kellogg designed circulating fluidized bed (CFB) reactors at Sasol 1 in the 1950s, the commercial high-temperature Fischer–Tropsch (HTFT) process has had a dynamic ongoing development resulting, recently, in the introduction of Sasol advanced synthol (SAS) reactor operation only at Secunda, 1999. It has reached a stage now where the emphasis has shifted for developing a catalyst tailored to these reactors and current market requirements. This paper follows the development of the reactor technology since the early 1940s, highlighting the major developments and giving indications of the effect thereof on gas throughput and bulk product yields. The paper traces Sasol’s journey utilizing the sound, but unproven pilot plant scale-up of Kellogg, to a routine day to day operation and profitable commercial process by means of innovative design changes, general state-of-the-art advances and, importantly, experience! 相似文献
89.
江西铜业集团公司是一个集采矿、选矿、冶炼、加工于一体的现代化大型企业,自创建以来,不断探索创新,各项工艺、技术日趋成熟。在发展壮大过程中,江铜坚持走循环经济之路,依靠科技生产力和实用的管理手段,从技术和细节入手,持续提高各种矿产资源回收率,树立“资源-产品-再生资源-再生产品”的新经济理念, 充分回收利用生产过程中产生的废气、废渣、废水、余热等,在“做大、做强、做优”企业的前提下,实现了社会效益优、经济效益高、资源使用省的现代企业目标。 相似文献
90.
只要利用闭路磨矿流程给料和产品的粒度分布,通过非线性最优化方法估计出模型参数,就可以求出磨矿回路的循环负荷,因而从理论上省略了测定循环负荷的工作量,具有一定的实际意义。 相似文献