In the low-carbon era, photovoltaic power generation has emerged as a pivotal focal point. The inherent volatility of photovoltaic power generation poses a substantial challenge to the stability of the power grid, making accurate prediction imperative. Based on the integration of a backpropagation (BP) neural network and a genetic algorithm (GA), a prediction model was developed that contained two sub-models: no-rain and no-snow scenarios, and rain and snow scenarios. Through correlation analysis, the primary meteorological factors were identified which were subsequently utilized as inputs alongside historical power generation data. In the sub-model dedicated to rain and snow scenarios, variables such as rainfall and snowfall amounts were incorporated as additional input parameters. The hourly photovoltaic power generation output was served as the model’s output. The results indicated that the proposed model effectively ensured accurate forecasts. During no-rain and no-snow weather conditions, the prediction error metrics showcased superior performance: the mean absolute percentage error (MAPE) consistently remained below 13%, meeting the stringent requirement of the power grid’s tolerance level below 20%. Moreover, the normalized root mean square error (NRMSE) ranged between 6% and 9%, while the coefficient of determination (R2) exceeded 0.9. These underscored the remarkable prediction accuracy achieved by the model. Under rainy and snowy weather conditions, although MAPE slightly increased to the range of 14% to 20% compared to that of scenarios without rain and snow, it still adhered to the stringent requirement. NRMSE varied between 4.5% and 8%, and R2 remained consistently above 0.9, indicative of satisfactory model performance even in adverse weather conditions. The successful application of the proposed model in predicting hourly photovoltaic power generation output during winter in Henan Province bears significant practical implications for the advancement and integration of renewable energy technologies.

对GB/T 10184-2015与GB 10184-88锅炉效率计算方法进行了比较,指出2个标准在锅炉效率定义、基准温度、固体未完全燃烧热损失、散热损失、高温脱硝装置的影响、修正项目、空气预热器性能等方面的差异,通过锅炉效率算例对2个标准的计算结果进行了比对分析,并指出了 GB/T 10184-2015存在的问题,对于火电机组锅炉效率测试具有指导意义.

Although more and more desulfurization equipment has been put into use in sintering plants, how to effectively remove sulfur dioxide from sintering flue gas in a desulfurization tower is still a great challenge in China. The desulfurization tower, as a critical part, needs further improvement and optimization. Therefore, based on the numerical simulation of the flow field of the ammonia-based wet desulfurization tower for sintering flue gas, ANSYS CFX is applied to conduct structural optimization research. Comparing the flow field distribution under different structure conditions, the results show that the flue gas distribution of the dual inlet tower is more uniform than that of the single inlet tower. The designed baffle not only effectively blocks the entry of the spray slurry, but also improves the flue gas distribution; the deflector with its simple structure, convenient operation, and stepped distribution installed in the entrance section can improve the uniformity of the flow field distribution. Based on the comprehensive analysis, these optimized structures are recommended in the design of an ammonia-based wet sintering flue gas desulfurization tower. This work not only develops a simulation of the desulfurization tower but also provides practical structures.

某电厂热一次风温度偏高,采用VB语言编程计算改变空预器转向产生的热力经济性影响,结果显示改变空预器旋转方向能有效降低一次风温,同时提高二次风温、降低排烟温度,提高锅炉效率、降低机组供电煤耗,有利于降低炉渣含碳量、降低一次风机耗电量.

针对一次风机严重失速事故频发,通过失速现象调查、风机特性测试和叶片检查,开展分析研究,确定了风机失速的原因.风机叶片磨损使风机性能曲线发生改变,并导致风机出力降低.为平衡并列运行风机的电流,不对照叶片实际角度而偏移动叶定位,使运行中的风机叶片角度偏离设计范围.采取技术措施后,风机失速得到有效避免.最后通过叶片更换和动叶规范定位彻底解决了问题.

为应对火电机组低粉尘浓度排放的环境要求,袋式除尘器被广泛使用,但由于袋的结构和布置等原因造成流场分布不均匀导致袋的破损和使用寿命缩短.文章采用计算流体动力学Fluent软件,利用多孔介质渗流模型对袋式除尘器单个滤袋流场进行了数值模拟,研究了滤袋压差、渗透率以及长度对滤袋流场分布的影响;研究表明为了达到最佳除尘效果,并保证滤袋的正常使用寿命,必须保证滤袋边界流动速度分布的均匀性;而控制滤袋的渗透率在合适的范围内是保证滤袋过滤介质速度均匀分布的关键要素.

To prevent and dispose all kinds of problems occurred in the air preheaters of the large coal-fired power plants and improve the performance of the air preheaters, the representative problems of the air preheaters in Henan province was summarized with the statistical method. With specific cases, its adverse impact for boilers and auxiliary machines were analyzed. The main reasons for causing these problems were design flaws, maintain undeserved, poor blowing effect and high sulfur content in coal that can cause acid corrosion to the air preheaters. A series of countermeasures were put forward to resolve the problems.

The computer numerical simulation of swirling burner in cold state was taken in this paper. The swirling intensity and the expansion cone angle of the secondary air were the main simulation content. The outlet flow field and form of the combustor were got through the simulation, and the comparison of the airflow diffusion angle and the return flow zone were analyzed, and then the guidance suggestions on the design modification and operation adjustment of the existing swirl burner were proposed.

A tangentially fired boiler with twin furnace is tested to analyze the effect of such factors as primary air velocity, air distribution mode, over fired air, oxygen content on NOx and boiler efficiency during boiler combustion adjustment, providing reference for boiler operation optimization and reducing NOx emissions.

Poor heat transfer effect of the rotary air preheater was considered as the main reason for the phenomenon occurs in a 600 MW ultra supercritical unit boiler:low hot air temperature and high exhaust gas temperature.To solve this problem,300 mm height carbon steel heat storage component was added to the heat section of preheater.Results show that,heat transfer is significantly enhanced.Temperature rise of the primary and secondary air,and its drop of the delayed side both meets the design value.Heat exchange efficiency of the flue gas side reaches 70.78%,higher than the designed value.

The main problems of the air preheaters in large units are large air leakage rate,high resistance and poor heat transfer etc.The paper analyzed the reasons for these problems and it's adverse effects of the operation of the units and the Boiler Fans,provided the corresponding measures.It had reference significance to the operational maintenance of the air preheaters.

Coal fineness is very important for the safe、stable and economic operation of the boiler.The paper introduced the primal problems in the sampling and analysis of the pulverized coal,analysed the reasons of leading to the unrepresentative coal fineness,provided improving suggestion.It had instructive significance for strengthening the supervision of the coal fineness and enhancing the economical efficiency of the boiler.

Owing to worsening coal quality,the dense phase pneumatic ash conveying system of a 300 MW unit can't be in normal operation,making the output capacity of said ash conveying system to be increased,the transporting stability of said system to be decreased,the margin of compressed air used for transportation in the said system to be reduced,the back-pressure in ash bunker to be enhanced,and the wornout of the said system to be intensified.The above-mentioned problems have been analysed,and corresponding solving measures being put forward.

Thermal decomposition of cement raw meal and limestone was investigated under pure N2 atmosphere with thermo-gravimeter (TG). In terms of the integral, differential and multi-rate equation(Kissinger method) , reaction mechanism and kinetic parameters are obtained. The results indicate that the decomposition of cement raw meal and limestone is in according with the shrinking cylinder mechanism with surface reaction rate controlling. Besides the correlation between the apparent active energy E and pre-exponential A has been found for different mechanism functions, heating rates and sources.

In this paper, thermal decomposition of a kind of limestone is investigated under pure N2 atmosphere with thermo-gravimetre (TG). In terms of three methods, reactive mechanism and kinetic parameters are obtained. The results indicate the shrinking cylinder model with surface reaction rate controlling mechanism is the best model fitting the experiment data, and the kinetic method is efficient on selecting the mechanism function.

为了解流化床燃烧过程中痕量元素的分布与富集规律,以流化床燃煤过程为研究对象,在实验室的小型机理性试验台架上进行实验,研究了煤中痕量元素的排放特点.实验模拟流化床低温燃烧的特点,6种典型煤分别在650℃、800℃、950℃三个工况下燃烧,分析得到Pb、Cr、Cd等痕量元素大部分留在灰中.Hg在灰中的富集规律不明显.