天然气电厂CCS Ready评估—高井电厂CCS Ready的条件评估及能耗分析

发布时间：2018-01-04 19:10

本文关键词：天然气电厂CCS Ready评估—高井电厂CCS Ready的条件评估及能耗分析　出处：《北京交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：近年来,随着人类工业活动的快速发展,越来越多的化石燃料燃烧以及绿色植被的减少,大气中CO2的含量逐年增加。应对全球气候变暖,CO2的减排势在必行。目前,在降低C02排放量的方法中,C02的捕集和封存技术(CCS)将成为未来的发展趋势。CCS技术可将C02从排放源中捕获,然后永久的封存于地下。然而,实施CCS目前仍然面临着重大的技术、法律、政策、以及大规模实施的经济障碍。解决这些障碍,需要一定的时间,因此,CCS Ready的概念应运而生。作为清洁能源,天然气发电相对环保,天然气电厂具有更高的能源效率。但在燃气—蒸汽联合循环机组产生的烟道气中仍存在大量的二氧化碳。因此,从长远考虑,天然气发电厂需通过CCS技术减少二氧化碳的排放。当强制减排的监管措施和经济激励机制出现,CCS Ready电厂能够较容易地改造成CCS电厂。本文主要研究了： (1)天然气发电的基本情况以及国内外CCS和CCS Ready的定义、研究现状、CCS Ready的国际基准和法规。以高井NGCC-CHP电厂为例,计算得出电厂在全厂90%CO2捕获规模下的CO2捕获量为445.2t/h。根据电厂实际情况及捕获量,参考国际学术研究及以往使用经验,对比C02捕获技术方案,为高井电厂选择燃烧后捕获CO2MEA化学吸收法。 (2)采用Aspen Plus模拟软件对捕获流程进行模拟,得出高井电厂CO2捕获系统的尺寸。模拟计算出高井电厂捕获设备共18套,其中洗涤塔塔径7m,高24m；吸收塔塔径10m,高27m；再生塔塔径6m,高21m。 (3)采用Aspen Plus模拟软件对捕获流程进行模拟,得出高井电厂CO2捕获系统的电耗、能耗和物耗,并通过调节主要参数进一步优化工艺过程。模拟得出捕获系统每捕获1吨CO2消耗的能量为3.53GJ/tCO2,捕获系统的总电耗为74MW/h,消耗循环冷却水量为114m3/tCO2。调节吸收剂浓度、贫液负荷、再生塔压力、再生塔入口富液温度,最终得出,MEA吸收剂最佳浓度为30%,贫液负荷在0.25mol CO2/mol MEA,再生塔压力为2bar,再生塔入口温度为90℃时,捕获条件最优。 (4)电厂蒸汽循环与C02吸收系统的整合办法。对比了三种外部供热系统为再沸器提供能量的方案,最终选择应用电厂内部的蒸汽循环供给再生所需能量。分析得出选择中压和低压后部分330℃、0.36MPa蒸汽作为进入再生塔底部再沸器热源,根据模拟得出的C02捕获能耗,计算出全厂三台机组需要的总蒸汽量为598.94t/h。 (5)高井NGCC-CHP电厂满足CCS Ready要求的必要条件和障碍,主要对捕获就绪方面做出详细评估。目前,高井电厂在烟气脱硫脱硝、冷却水系统和消防方面已经达到了捕获就绪的要求。高井电厂还需要进行捕获设备和改造空间的预留,蒸汽轮机及辅助系统的改造,增加捕获污水处理系统、相关电气及管道构架设施、汽水分析监测点并做好CCS电厂安全运行预案；估算得出高井电厂新增总面积约为90020m2,其中CO2捕获设备占地面积为87320m2,污水处理厂、药品仓库、维修车间、停车场、卸货区等占地面积2700m2,画出捕获设备的平面示意图。另外,介绍了运输就绪和封存就绪的基本要求,并根据高井电厂的实际情况做出评估。 (6)选择高井电厂蒸汽轮机的改造方案。分别对比低压气缸节流、低压气缸浮压以及低压气缸离合连接改造的优缺点以及对电厂的影响,最终选择低压气缸浮压的方式作为高井NGCC-CHP电厂的蒸汽轮机改造方案。 (7)电厂在ISO工况下,添加C02捕获设备对电厂整体发电效率的影响。研究一台机组的分析结果得出,添加C02捕获设备后电厂发电效率的损失约为15.4%,其中再沸器能耗损失为45.24MW,使发电损失9.97%；捕获设备电耗为24.7MW,使发电损失5.4%。 (8)从政策、资金成本、和高井电厂的实际情况等方面,总结了高井电厂实现CCS Ready存在的差距,并对我国未来发展CCS Ready进行了展望。
[Abstract]:In recent years, with the rapid development of human industrial activities, more and more fossil fuel burning and green vegetation decrease, the content of CO2 in the atmosphere increases year by year. To deal with global warming, CO2 emission reduction is imperative.
At present, the method to reduce C02 emission, capture and sequestration of C02 (CCS) will become the future development trend of the technology of.CCS C02 can be discharged from the source capture, then permanently sealed in the ground. However, the implementation of CCS is still facing major technology, law, policy, and large-scale the implementation of the economic barriers. To solve these obstacles, take some time, therefore, the concept of CCS Ready came into being.
As a clean energy, natural gas power relative to environmental protection, natural gas power plant has a higher energy efficiency. But there are still a lot of carbon dioxide in flue gas generated in the gas steam combined cycle unit. Therefore, in the long term, natural gas power plants to reduce carbon dioxide emissions by CCS technology. When the mandatory supervision measures and economic incentive mechanism, CCS Ready power plant can be easily transformed into CCS power plant.
This paper mainly studies the following:
(1) the research status quo of natural gas power generation, definition, domestic and foreign CCS and CCS Ready, CCS Ready international standards and regulations. With high well NGCC-CHP power plant as an example, calculated the power plant in the plant 90%CO2 capture scale under CO2 capture capacity of 445.2t/h. according to the actual situation of the power plant and the capture, international academic research reference and past experience, comparison of C02 capture technology scheme, selection of post combustion capture CO2MEA chemical absorption method for Gaojing Power Plant.
(2) Aspen Plus simulation software is applied to simulate the capture process, and the size of CO2 acquisition system in the high well power plant is simulated. The simulation calculation shows that there are 18 sets of acquisition devices in the high well power plant, including washing tower diameter 7m, high 24m, absorption tower diameter 10m, high 27m, regeneration tower diameter 6m, high 21m..
(3) using Aspen Plus to capture process simulation software, the high power consumption of power plant CO2 wells capture system, energy and material consumption, and by adjusting the main parameters to further optimize the process. The simulated capture system each capture the consumption of 1 tons of CO2 energy is 3.53GJ/tCO2, the total power consumption of acquisition system of 74MW/h, consumption cycle the cooling water to regulate the 114m3/tCO2. concentration of absorbent, poor liquid load, regeneration tower pressure regeneration tower entrance rich liquid temperature, finally, the optimum MEA absorbent concentration is 30%, the lean liquid load in 0.25mol regeneration tower CO2/mol MEA, pressure 2bar, regeneration tower entrance temperature is 90 degrees centigrade, capture the optimal conditions.
(4) steam cycle and C02 power plant absorption system. Compared with the methods of integrating three kinds of external heating system for the reboiler to provide energy solutions, finally choose the energy needed to supply steam cycle power plant regeneration and application. Internal analysis selection of medium and low voltage part after 330 DEG C, 0.36MPa as steam enters into the regenerator bottom reboiler according to the simulation results of the heat source device, C02 capture energy, calculate the total amount of steam to the three units of the 598.94t/h.
(5) high wells NGCC-CHP power plant necessary condition to meet CCS Ready requirements and main obstacles, make a detailed assessment of the capture ready. At present, Gaojing Power Plant NOx in flue gas desulfurization, cooling water system and fire has reached the capture ready. Gaojing Power Plant needs to capture equipment and improvement of the space reserved the transformation, steam turbine and auxiliary system, increase the capture of the sewage treatment system, electrical and pipeline architecture facilities, monitoring and analysis of soda do CCS power plant safe operation plan; estimate that new Takai power plant a total area of about 90020m2, which covers an area of 87320m2 CO2 capture equipment, sewage treatment plant, warehouse, workshop, parking lot, unloading zone covers an area of 2700m2, draw the plane capture device diagram. In addition, this paper introduces the basic requirements of transport and storage is ready, and according to the high wells power plant Make an assessment of the actual situation.
(6) select the reconstruction scheme of Gaojing Power plant steam turbine low pressure cylinder respectively. Comparing the advantages and disadvantages of throttling, low pressure cylinder floating pressure and low pressure cylinder clutch connection and influence on the transformation of the power plant, the final choice of low pressure cylinder floating pressure way as the steam turbine retrofit scheme of Takai NGCC-CHP power plant.
(7) power plant in ISO condition, affect the efficiency of power generation equipment to add C02 to capture the whole power plant. Analysis of the results of a unit, add C02 capture device after power generation efficiency loss is about 15.4%, the reboiler energy loss is 45.24MW, the power loss of 9.97%; capture equipment, the power consumption is 24.7MW. The power loss of 5.4%.
(8) from the policy, the cost of capital and the actual situation of Gao Jing power plant, the paper summarizes the gap between CCS Ready and the future development of CCS Ready.

【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：X511;X773

【参考文献】