The study addresses the design and operational features of an active condensation (AC) system aimed at improving the energy efficiency of a 3rd generation district heating (DH) plant. Several similar biomass-utilizing plants have recently been built in the Republic of Serbia. The plant is equipped with biomass-fired boilers totaling 2 MW capacity, utilizing varying qualities of wet wood chips. The goals are: (i) to determine optimal constant and variable quench temperatures; (ii) to calculate the electricity consumption of ancillary devices and assess their impact on AC system performance; (iii) to evaluate the effect of biomass moisture variations on system size and performance; (iv) to assess the economic viability of integrating the AC system; and (v) to establish selection and design criteria for the heat pump (HP). For a given commercial HP, an optimal quench temperature exists, dependent on the minimal temperature lift required by the HP. This temperature can be calculated simply by subtracting the minimal HP lift from the lowest possible temperature that the HP can supply to a DH system at the average outdoor temperature. Consequently, an optimal variable quench temperature exists that should be adjusted to enable the HP to operate with its minimal temperature lift.

中文翻译：

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用于提高生物质区域供热厂能源效率的主动冷凝系统的设计和运行特点


该研究探讨了主动冷凝（AC）系统的设计和运行特征，旨在提高第三代区域供热（DH）工厂的能源效率。塞尔维亚共和国最近建造了几座类似的生物质利用工厂。该工厂配备了总容量为 2 MW 的生物质燃烧锅炉，利用不同质量的湿木片。目标是： (i) 确定最佳的恒定和可变淬火温度； (ii) 计算辅助设备的耗电量并评估其对空调系统性能的影响； (iii) 评估生物质水分变化对系统规模和性能的影响； (iv) 评估整合空调系统的经济可行性； (v) 建立热泵 (HP) 的选择和设计标准。对于给定的商用 HP，存在最佳淬火温度，具体取决于 HP 所需的最小温度提升。该温度可以简单地通过从 HP 在平均室外温度下向 DH 系统提供的最低可能温度减去最小 HP 升力来计算。因此，存在最佳的可变淬火温度，应对其进行调整以使HP能够以最小的温升运行。