基于煤种掺烧模式的锅炉燃烧预测模型及应用

发布时间：2018-03-25 11:35

本文选题：燃烧NO_x浓度　切入点：飞灰含碳量　出处：《浙江大学》2017年硕士论文

【摘要】：我国能源消费结构在由煤为主导向多元化发展,但煤炭依然占据着主导地位,而由煤炭燃烧带来的环境污染日益受到重视,尤其是燃煤电厂产生的固、液、气污染。在保证安全和环保的前提下提高经济性是燃煤电厂的目标,因此合理的优化运行方式、煤种掺烧方案以及煤种采购显得异常重要。对锅炉燃烧情况的预判可以为此提供参考。本文基于电厂实际运行数据和入炉煤煤质信息,综合考虑了磨煤机组合方式、配风方式等运行参数和煤质信息,利用支持向量机建立起锅炉燃烧NO_x浓度、飞灰含碳量和排烟温度的预测模型。将遗传算法和交叉验证法结合对预测模型的参数进行优化与选择,建立起的模型有良好的学习和泛化能力。从校验样本中选取部分工况作为基础工况,在其他条件不变的情况下,研究在选定的这些工况下,单因素如:氧量、燃尽风率、煤种及掺配比例等,对锅炉NO_x浓度、飞灰含碳量及排烟温度的影响。对这些选定的工况研究结果表明氧量、燃尽风率、煤种及掺配比例对NO_x有较大的影响,而飞灰含碳量和排烟温度与氧量、燃尽风率及煤种密切相关。根据模型的研究结果,计算各个选定工况的煤耗,结合实际煤炭价格、液氨及石灰石粉价格计算氧量、燃尽风率、煤种、掺配比例等对发电成本、环保成本及综合成本的影响。分析结果显示在本文选定的这些工况下,随着氧量增加发电成本与环保成本均增加,燃尽风率的增加会使得发电成本上升但环保成本下降,综合成本表现为上升,煤种对发电成本和环保成本影响巨大,掺烧高硫煤和蒙煤有利于提高经济性。
[Abstract]:China's energy consumption structure is developing from coal to diversification, but coal still occupies a dominant position, and environmental pollution caused by coal combustion has been paid more and more attention, especially the solid and liquid produced by coal-fired power plants. Gas pollution. Improving economic efficiency under the premise of ensuring safety and environmental protection is the goal of coal-fired power plants. It is very important to mix coal with coal and to purchase coal. The prediction of boiler combustion can provide reference for this. Based on the actual operation data of power plant and coal quality information, the combined mode of pulverizer is considered in this paper. The NO_x concentration of boiler combustion was established by using support vector machine and operation parameters such as air distribution mode and coal quality information. The prediction model of carbon content in fly ash and smoke exhaust temperature. Genetic algorithm and cross validation method are combined to optimize and select the parameters of the prediction model. The model has good learning and generalization ability. Selected part of the check sample as the basic operating conditions, in the case of other conditions unchanged, under these conditions, the single factor such as oxygen, burnout rate, The effects of coal type and blending ratio on NO_x concentration, carbon content in fly ash and exhaust gas temperature of boiler are studied. The results show that oxygen content, burnout rate, coal type and blending ratio have great influence on NO_x. However, the carbon content of fly ash and the exhaust temperature are closely related to oxygen content, burnout air rate and coal type. According to the results of the model, the coal consumption of each selected working condition is calculated, and the oxygen content and burnout rate are calculated according to the actual coal price, the price of liquid ammonia and limestone powder. The effects of coal and blending ratio on the cost of power generation, environmental protection and comprehensive cost. The results show that the cost of power generation and the cost of environmental protection increase with the increase of oxygen under these selected conditions. The increase of burnout rate will increase the cost of power generation but decrease the cost of environmental protection, and the comprehensive cost will be increased, and the coal will have a great impact on the cost of power generation and environmental protection. Mixing coal with high sulfur and coal will improve the economy.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM621.2

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