煤炭热值对机组运行和电煤消费影响及其应对措施

煤质是影响电厂运行过程中节能环保水平以及电煤消费量的关键因素,从煤炭的发热量、灰分、水分、含硫含氮量等参数的变化分析了煤质对机组运行及电煤消费量的影响机理。结合江苏省主要燃煤发电企业近两年入炉煤热值、发电量及发电耗煤数据,定量分析了电煤热值变化对全省电煤消费量的影响,按照2022年全省煤电发电量测算,全省电煤年平均热值每提高418.4 kJ/kg,全年电煤消费总量减少约3.9×10^(6) t,减少CO_(2)排放约1.0×10^(7) t。因此,从强化源头管控、合理储配掺烧、实施更新改造、精细运行管理和优化存煤结构等方面,提出控制电煤热值的相关措施,降低机组发电煤耗,控制污染物排放,起到节能减排的作用。

广东电力低碳高质量发展下的电煤需求影响分析

从广东电力清洁、低碳、高质量发展的角度,采用灰色关联度分析法和对数平均迪氏指数法,阐述了人口规模、经济发展、产业结构、发电强度、新能源发电强度、用电强度、碳排放强度以及电煤消耗强度8个因素对省域电煤消费量的动态影响。分析2019—2022年各季度和2012—2022年各年度的广东省电煤消费量的影响因素,并利用神经网络极限学习机(extreme learning machines, ELM)、长短期记忆(long short-term memory, LSTM)网络、卷积双向长短期记忆网络(convolutional neural networks-bi-directional LSTM,CNN-BILSTM)3种模型对该省未来的电煤消费量开展季度预测和分析。研究发现:在季度分析中,经济发展效应是促进电煤消费量增加的首要驱动因素,产业结构效应是抑制电煤消费量增加最重要的驱动因素,其促进和抑制作用十分明显;在年度分析中,经济发展效应是电煤消费量增加最重要的驱动因素,碳排放强度效应是降低电煤消费量的首要驱动因素;在对未来电煤消费量的预测上,CNN-BILSTM模型的平均误差率保持在10%以下,可以为广东省电力低碳高质量发展路径规划提供数据和技术支撑。

高效洁净燃煤发电发展路线研究

由于我国煤电基数较大,尽管平均供电煤耗有明显下降趋势,但煤电机组总发电量和煤炭消费量仍将处于上升趋势。如按现有发电技术水平预计(按2010年平均供电煤耗355 g/kW·h,电煤平均热值21 MJ/kg估算),2020年、2030年和2050年,电煤消费总量将达到24.06亿t/a、27.94亿t/a和26.95亿t/a[1],这将给电煤供应和环境保护带来很大压力。要降低供电煤耗,减少燃煤污染物排放,必须大力发展高效清洁发电技术,如发展超临界、超超临界、IGCC、煤基多联产系统、烟气脱硫系统(FGD)、催化氧化还原脱氮技术(SCR)、二氧化碳捕集与埋藏技术等。

Performance analysis of a solar-aided power generation(SAPG) plant using specific consumption theory

In contrast to a traditional coal-fired power generation plant where steam extracted from a turbine is used to preheat the feedwater in all preheating stages, a solar-aided power generation(SAPG) plant uses solar heat to replace a part or all of the extracted steam in one or more preheating stages. The performance of an SAPG plant with different replacements is investigated in this study by using specific consumption theory(SCT). Fuel-specific and cost-specific consumption models for SAPG plants are built based on the SCT. A typical 330 MW coal-fired power plant is used as the study case. The performance of the SAPG plant in terms of specific consumption, with steam obtained from the first through the eighth(except for the fourth) stages of extraction replaced by solar heat, is compared with that of the reference coal-fired power plant. The fuel-specific consumption of the SAPG plant is determined to be lower than that of the reference coal-fired power plant. The fuel-specific consumption accrual distribution in SAPG plants is used to assess the effect of each individual replacement. Effective strategies to reduce the specific costs of the SAPG and coal-fired power plants are proposed based on the results of this study.