储热技术在地热公建供暖中的优化应用与运行策略研究

Optimize Application and Operation Strategy of Heat Storage Technology in Geothermal Heating of Public Buildings

本文分析地热公共建筑供暖的热负荷特性和地热井潜水泵在实际生产过程中启停和变频特点,提出采用储热技术提高地热资源利用效率和效益的方法,并通过建立筛选评价指标结合数值模拟和自编程序,对储热材料筛选、储热比例优化与系统运行策略全过程开展研究。结果表明,水作为地热公共建筑供暖储热材料的技术经济性最好,潜热储热中可优先考虑三水合乙酸钠提高储热密度。以陕西咸阳公建供暖和假定采暖时段为例进行研究,当采用水作为储热材料时最佳储热比例为42.2%,可使财务内部收益率增加10.87%,采用其它储热材料时,单位储热负荷投资不宜高于200元/k W·h,并通过程序实现最优运行策略的输出。

Based on the thermal load of geothermal heating in public buildings and the start-stop and frequency conversion of submersible pump in geothermal well,a method is proposed to improve the efficiency and benefit of geothermal resource utilization by using heat storage technology.The whole process from screening of heat storage materials,optimization of heat storage proportion to implementation of system operation strategy is investigated by setting up a screening evaluation index system that combines with numerical simulation and self-programming.The results show that water,as the medium of geothermal heating for public buildings,can deliver the best technical and economic effects,and priority should be given to sodium acetate trihydrate in latent heat storage to improve the heat storage density.The method was verified in the public building heating in Xianyang.The results show that the optimal proportion of heat storage was 42.2% when water was used as the medium of heat storage,and it increased the internal rate of return by 10.87%.When other heat storage materials were used,the investment per unit heat storage load should not be higher than 200 RMB/k W·h.Finally,the optimal operation strategy was exported by program.