山东某老旧小区大温差清洁供暖系统应用分析

Application analysis of clean heating system with large temperature difference in an old residential area in Shandong

以山东某老旧小区片区为例,采用高效梯级利用污水低品质热的大温差清洁供暖工艺进行供暖改造,对改造后系统的节能及技术经济性进行探究分析。结果表明:采用双级污水源热泵+乙二醇换热器结构工艺,可以有效实现污水低品质热的高效梯级利用,降低第二级热泵蒸发器因中水温度过低导致的结冰、胀裂风险,最低可实现中水1.5℃超低温排放;用户侧针对不同末端形式、不同温度的供暖水需求,采用梯级降温供暖工艺,实现小流量、大温差供暖;与燃气锅炉供暖工艺相比,污水源热泵供暖工艺采用电能驱动,不受天然气价格及气量限制的影响,供暖稳定性较好,且运行成本较低,可盈利4.19元/m2,项目主设备投资回收期约5.7年。

Taking an old residential area in Shandong as an example, a high-efficiency step-by-step large temperature difference clean heating process using the low-quality heat of sewage is adopted for heating renovation, and the energy-saving and technical economy of the reformed system are analyzed. The results show that the two-stage sewage source heat pump + ethylene glycol heat exchanger structure process can effectively realize the high-efficiency cascade utilization of low-quality sewage heat, and avoid the risk of freezing and cracking of the evaporator of the second-stage heat pump caused by the low temperature of reclaimed water, and can realize the ultra-low temperature discharge of reclaimed water at 1.5 ℃ at the lowest. According to the demand of heating water with different terminal forms and different temperatures,users adopt the cascade cooling heating technology to realize small flow and large temperature difference heating.Compared with the gas boiler heating process, the sewage source heat pump heating process is driven by electric energy,which is not affected by the price of natural gas and the limitation of gas volume. Its operating cost is low, with a profit of 4.19 yuan per square meter, and the payback period of the main equipment of the project is about 5.7 years.