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完整後設資料紀錄
DC 欄位 | 值 | 語言 |
---|---|---|
dc.contributor.advisor | 陳誠亮 | |
dc.contributor.author | Shao-Chiu Chen | en |
dc.contributor.author | 陳少秋 | zh_TW |
dc.date.accessioned | 2021-06-08T03:35:54Z | - |
dc.date.copyright | 2019-08-05 | |
dc.date.issued | 2019 | |
dc.date.submitted | 2019-07-29 | |
dc.identifier.citation | [1]'Energy Production & Changing Energy Sources,' [Online]. Available: https://ourworldindata.org/energy-production-and-changing-energy-sources.
[2]'Energy Flow Charts: Charting the Complex Relationships among Energy, Water, and Carbon,' [Online]. Available: https://flowcharts.llnl.gov/. [3]“Piping drawing of a real case steam pipeline network,” Chinese Petroleum Corporation, classified information. [4]Xianxi, L., Shubo, L., Menghua, X., & Ying, H., 'Modeling and simulation of steam pipeline network with multiple supply sources in iron& steel plants.,' in In Control and Decision Conference (CCDC), pp. 4667-4671, 2016. [5]García-Gutiérrez, A., Hernández, A. F., Martínez, J. I., Cecenas, M., Ovando, R., & Canchola, I., 'Hydraulic model and steam flow numerical simulation of the Cerro Prieto geothermal field,' Applied Thermal Engineering 75, pp. 1229-1243, 2015. [6]Białecki, R. A., & Kruczek, T., 'Frictional, diathermal flow of steam in a pipeline,' Chemical engineering science 51, pp. 4369-4378, 1996. [7]Salmasi, F., Khatibi, R., & Ghorbani, M. A., 'A study of friction factor formulation in pipes using artificial intelligence techniques and explicit equations,' Turkish Journal of Engineering and Environmental Sciences 36, pp. 121-138, 2012. [8]Wang, H., Wang, H., Zhu, T., & Deng, W., 'A novel model for steam transportation considering drainage loss in pipeline networks,' Applied Energy 188, pp. 178-189, 2017. [9]H. Cross, Analysis of flow in networks of conduits or conductors, University of Illinois at Urbana Champaign, College of Engineering. Engineering Experiment Station, 1936. [10]D. Brkić, 'Iterative methods for looped network pipeline calculation,' Water resources management 25, pp. 2951-2987, 2011. [11]Wang, S. H., Wang, W. J., Chang, C. Y., & Chen, C. L., 'Analysis of a Looped High Pressure Steam Pipeline Network in a Large-Scale Refinery,' Industrial & Engineering Chemistry Research 54, pp. 9222-9229, 2015. | |
dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/21499 | - |
dc.description.abstract | 化工程序設計經常使用蒸汽作為驅動透平之動力來源或加熱反應器、蒸餾塔等之熱源。蒸汽供應在工廠中常以中央鍋爐產生高壓蒸汽後,直接驅動透平發電,或經由管線配送至各單元進行使用。由於廠區內有多個蒸汽使用單元分散在各地,且各使用單元所需之蒸汽壓力與溫度多不相同,單一鍋爐常無法負荷全廠區的蒸汽供應,再考量到鍋爐需要安排維修時程,各單元可能需要複數條蒸汽供應管線來調度蒸汽,導致現場蒸汽管線網路錯綜複雜,一旦發生操作問題,蒸汽溫度或者壓力有異常狀況,經常難以在第一時間掌握異常狀況的發生原因與位置。另外,不當的管線配置與蒸汽分配,也可能會造成無謂的蒸汽冷凝,造成額外的損失。
本論文將針對蒸汽管線網路進行模擬,透過分析質量平衡、動量平衡與能量平衡計算單管中蒸汽的能量損耗,並將管線連接點與管線進行編號,標示蒸汽供應點與蒸汽使用點,藉此描述蒸汽管線網路中的連接情況;對於蒸汽管線網路中可能出現的環狀管線,會以Hardy-Cross法計算環路中的順逆方向之流動的壓力損耗相等之流量情況,即為正確之流量。 本研究之目標為研究蒸汽管線網路設計與操作之注意事項以減少能源之浪費。蒸汽冷凝為本研究中之主要考量,因冷凝代表額外的蒸汽供應需求與低效率之蒸汽運輸,因此如何避免過大的溫度損耗會是主要的探討方向。本研究分別模擬並分析以下三種情境:單一蒸汽供應之樹狀網路、多蒸汽供應之樹狀網路、樹狀網路與環狀網路之蒸汽調度比較。透過以上情境分析,找出在設計蒸汽管線網路與調度蒸汽時應注意之設計與操作限制。 在單一蒸汽供應之樹狀網路分析中,目標為分析蒸汽供應端與使用端之分佈對於蒸汽溫度與壓力之影響。結果顯示低蒸汽流量導致較大的溫度損耗,主要原因為能量損失與溫度與管件表面積有關,而相同的能量損失平均分配給較低流量之蒸汽會導致較大的溫度損耗。透過管件與蒸汽之參數計算,可以得知指定管線中之流量最小值,以避免高於預期的溫度下降發生。 在多蒸汽供應之樹狀網路分析中,目標為研究多蒸汽供應之調度對於蒸汽使用端之影響。結果顯示,在未達蒸汽供應操作限制前,將該網路分割作複數單一蒸汽供應可以集中蒸汽流量並減少流經管線面積,能減少能量與溫度損耗;若蒸汽用量過大無法由單一鍋爐負荷,基於蒸汽流量對於溫度損耗之影響會被抵銷,在冷凝未發生的前提下,蒸汽的調度對於使用端的影響甚小。在此情況下,選擇蒸汽調度對整體網路影響較小的蒸汽供應策略。 在樹狀網路與環狀網路之蒸汽調度比較中,蒸汽流量、管件長度與管徑對於壓力損耗之影響較明顯,可以此估計環狀管線中未設置流量計之管線蒸汽流量;比較相同蒸汽網路中,加裝環狀管線對於蒸汽調度之影響,在有蒸氣供應端維修情況下,環狀管線將蒸汽分流,雖小幅度增加溫度損耗,但可以有效的減少壓力損耗。但在加裝環狀管線時,管線連接點選擇對於蒸汽流量之變化有顯著影響。透過壓力損耗估計環狀管線中之流量,可以檢視環狀管線之設計是否合適,同時避免不必要之能量損失發生。 綜合上述分析,可以建立一套對於既有蒸汽管網之評估方法,檢視複雜管路結構中是否有過低的流量發生,並對於該發生管線檢視可行的解決方案,包含調整蒸汽供應、管件保溫之策略修正或額外之管線設計等。同時,本項研究之結果亦可以應用於現場蒸汽管網之設計、各蒸汽使用單元之位置分配,及調整各單元歲修時程安排,以降低對網路中其餘單元之影響。 | zh_TW |
dc.description.abstract | In most chemical engineering processes, steam is widely used as a heat source for distillation column and reactor. Steam is generated by boilers and distributed through pipeline to all steam users. Considering the location for all the steam users and the possible boiler maintenance situation, it is likely that there are several pipes connecting to each user, which forms a complex pipeline network. If emergency occurs, it is difficult to locate the problem at the first time. Also, improper pipeline design may lead to steam condensation that cause unnecessary waste of steam.
A steam network model is built in this work using mass balance, momentum balance and energy balance to calculate steam properties in a single pipe. By labelling the starting point and ending point of each pipe, a pipeline network is built, describing steam flow from boilers to users. For loop pipeline network, Hardy-Cross method is applied to calculate the identical pressure drop in clockwise and counterclockwise flow. The goal of this work is to develop general design and operation concepts that can minimize the waste of energy use. Steam condensation is the most concerned part in this work since it leads to requirement of extra steam generation. Three case studies are including in this work, which are single supplier in a branch network, multiple suppliers in a branch network, and comparison between branch network and loop network. In single supplier in a branch network case, the relationship between the location of the steam users and the steam properties is investigated. The result shows that lower steam flow rate will cause greater temperature drop because the total amount of energy loss is related to pipe design and steam temperature. With similar energy loss, smaller flow rate leads to larger temperature drop. A relationship between steam flow rate and temperature drop for given pipeline parameters is built to prevent condensation. In multiple suppliers in a branch network case, steam properties for a user with two suppliers with different flow rate is investigated. The result shows that separating the original network into several single supplier network can minimize the surface area and maximize the flow rate, which leads to the smallest temperature drop. If there is any limitation for boilers that the separation cannot be done, both the location and the steam supply amount make little influence to the system if the total pipe surface area is the same because the temperature drop due to the small flow rate and the average temperature of two flow cancel out if no condensation occurs. In comparison between branch network and loop network case, flow rate in loop pipeline is determined by pressure drop, and pressure drop is mostly influenced by steam flow rate, pipe length and pipe diameter, so flow rate in loop pipeline can be estimated by considering a branch network case with an additional pipe. Two maintenance cases is considered and comparison between branch network and loop network is done. The result shows that loop pipeline separates the steam flow rate, which decreases the pressure drop. However, temperature drop at the end of the loop pipeline should be concerned if small flow rate occurs. Estimation of flow rate in the loop can be done without considering the steam properties, and the result shows small difference with the model simulation. In this work, indicators for steam pipeline network performance evaluation are proposed. By mass balance calculation and loop flow rate estimation, flow rate distribution in network can be obtained. If the flow rate is lower than the lower limit for given temperature drop value, modification for insulator or steam supply strategy are required. With these information, redundant energy waste in the network can be prevented. | en |
dc.description.provenance | Made available in DSpace on 2021-06-08T03:35:54Z (GMT). No. of bitstreams: 1 ntu-108-R06524023-1.pdf: 6529480 bytes, checksum: 9a7aaa13de356fcc36e2e8656e7e9cf3 (MD5) Previous issue date: 2019 | en |
dc.description.tableofcontents | 致謝 ............................................................................................................................... I
摘要 ............................................................................................................................. II Abstract ...................................................................................................................... IV List of Figure ........................................................................................................... VIII List of Table ............................................................................................................... XI 1. Introduction ......................................................................................................... 1 1.1. World energy circumstances ...................................................................... 1 1.2. Energy use in industrial process ................................................................. 3 1.3. Problems of steam pipeline network........................................................... 5 1.4. Previous studies review.............................................................................. 6 1.5. Research motivation .................................................................................. 8 1.6. Dissertation organization ........................................................................... 9 2. Model Building .................................................................................................. 10 2.1. Single pipeline model .............................................................................. 10 2.2. Branch network model ............................................................................. 13 2.3. Loop pipeline network ............................................................................. 15 2.4. Iteration procedure ................................................................................... 18 3. Case Study ......................................................................................................... 20 3.1. Branch network with a single supplier ..................................................... 20 3.2. Branch network with multiple suppliers ................................................... 31 3.3. Comparison between branch and loop network ........................................ 39 3.4. Loop flow rate estimation ........................................................................ 63 4. Conclusion ......................................................................................................... 71 Reference .................................................................................................................... 73 Appendix .................................................................................................................... 74 Steam density calculation ................................................................................... 74 Steam enthalpy calculation ................................................................................. 75 Steam viscosity calculation ................................................................................ 75 Saturation Curve ................................................................................................ 76 Condensate enthalpy calculation ........................................................................ 76 Friction coefficient calculation ........................................................................... 77 | |
dc.language.iso | en | |
dc.title | 蒸汽管線網路之模擬與分析 | zh_TW |
dc.title | Modeling and Analysis of Steam Pipeline Network | en |
dc.type | Thesis | |
dc.date.schoolyear | 107-2 | |
dc.description.degree | 碩士 | |
dc.contributor.oralexamcommittee | 吳哲夫,錢義隆,李豪業,李瑞元 | |
dc.subject.keyword | 能源,蒸汽管網模擬,蒸汽調度分析,管線設計與溫壓變化, | zh_TW |
dc.subject.keyword | Energy,Steam pipeline network simulation,Steam supply analysis,Steam pipeline network temperature and pressure analysis, | en |
dc.relation.page | 77 | |
dc.identifier.doi | 10.6342/NTU201902041 | |
dc.rights.note | 未授權 | |
dc.date.accepted | 2019-07-29 | |
dc.contributor.author-college | 工學院 | zh_TW |
dc.contributor.author-dept | 化學工程學研究所 | zh_TW |
顯示於系所單位: | 化學工程學系 |
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