【摘要】 为描述二次能源的数量和品位,当前能源分析一般根据能源类型选取其固定的当量值和等价值,或者通过计算该能源最大做功能力来获得其折算电力的"能质系数",这两种方法均未能充分体现出实际生产过程的能源转换效率。通过分析典型二次能源的生产和加工转换过程,提出了"投入产出法"计算折标系数。应用该方法,结合蒸汽的利用流程和蒸汽品位等因素,推导出蒸汽当量值的计算公式。该公式以凝结水回收率作为权重,按凝结水回收和不回收的部分分别计算进出项目边界的工质焓差,进行加权平均得到蒸汽当量值。在此基础上,提出根据热源综合供热标煤耗折算蒸汽等价值的方法。通过典型案例的计算,发现热源的能源转换效率、蒸汽品位、凝结水回收率对其当量和等价折标系数均会产生非常明显的影响。通过对7℃/12℃冷冻水不同生产工艺转换效率的定量分析,得到其等价值的计算方法,认为其等价值范围基本在0.015～0.030kgce/MJ之间。在实际工程中,对于蒸汽、冷冻水等二次能源及压缩空气等具有能源"品位"特征的耗能工质,应结合生产工艺中的投入产出关系和本文提出的计算方法,进行其折标系数的合理计算,以合理评价项目能效水平。更多还原

【Abstract】 To describe the quantity and grade of secondary energy,the current energy analysis generally chooses the fixed energy calorific value and energy equivalent value according to the type of the energy or ob-tains the energy quality coefficient of the converted electricity by calculating the maximum working ability of the energy,but both methods fail to fully reflect the energy conversion efficiency during actual production.By analyzing the production and conversion process of typical secondary energy,this paper proposes Input-output Method to obtain the reasonable conversion coefficient for secondary energy.Using this method,the calculation formula for the calorific value of steam is derived combined with factors such as steam utilization process and steam grade.Taking condensate recovery rate as the weight coefficient,this formula respectively calculates the enthalpy difference of mediums in and out of the project battery limit according to condensate recovery and condensate non-recovery,and obtains the steam equivalent value by weighted averaging.On this basis,the method for the conversion of energy equivalent value of steam is proposed in accordance with the standard coal consumption of unit heat supply capacity.It is found through the calculation of typical cases that the conversion efficiency of heat source,steam grade and condensate recovery rate considerably influence the conversion coefficient for calorific value and equivalent value.By quantitatively analyzing the conversion efficiency of different production processes of chilled water(7 ℃/12℃),this paper demonstrates how to calculate the energy equivalent value which ranges from 0.015 to 0.030 kgce/MJ.For the actual energy evaluation of secondary energy such as steam and chilled water as well as energy-consumed mediums with characteristics of energy grade such as compressed air,the conversion coefficient should be calculated reasonably based on the input-output relationship in production processes and the calculation method proposed in this paper,so as to reasonably evaluate the energy consuming performance of the project.更多还原