针对寒冷地区现有厕所因冬季结冻而无法使用且不能实现粪污就地、可靠、连续、稳定地无害化处理等问题,构建了集太阳能集热、发电、粪污恒温厌氧发酵无害化处理于一体的多功能零能耗生态厕所,对比分析了晴天、多云和阴天3种典型工况下系统的运行性能.结果表明:晴天、多云和阴天的系统发电量分别为0.9、0.7和0.3 kW·h,光电转换效率分别为10.9%、11.2%和11.1%,系统累计耗电量为1.85 kW·h;3种工况下太阳能真空管集热器有效得热量分别为5.6、4.6和1.8kW·h,集热效率分别为50.8%、54.1%和46.2%,厌氧发酵袋平均温度分别为26.1、26和25.5℃,厕屋平均温度分别为16.7、15.9、14.6 ℃;系统全年可节约标准煤1 807 kg,投资回收期为7.6年.由此说明,所构建零能耗生态厕所系统适用于寒冷地区,可为寒旱地区厕所改造提供新途径.
To address the inability of conventional toilets in cold regions to operate in winter due to freezing, as well as the difficulty of achieving reliable, continuous, stable, and harmless treatment of feces on site, a multi-functional zero-energy ecological toilet system is developed. The proposed system integrates solar energy collection, power generation, and constant-temperature anaerobic digestion for waste sanitization. Its operational performance is experimentally investigated and comparatively analyzed under three representative weather conditions: sunny, cloudy, and overcast. The results show that the electricity generation under sunny, cloudy, and overcast is 0.9, 0.7, and 0.3 kW·h, respectively, with corresponding photovoltaic conversion efficiencies of 10.9%, 11.2%, and 11.1%. The cumulative power consumption of the system is 1.85 kW·h. Under three working conditions, the effective heat gains of the solar vacuum tube collector are 5.6, 4.6, and 1.8 kW·h, with heat collection efficiency of 50.8%, 54.1%, and 46.2%, respectively. The average temperature of anaerobic fermentation digestion bag is 26.1, 26, and 25.5 ℃, while the average temperature of toilet room is 16.7, 15.9, and 14.6 ℃, respectively. Moreover, the system is estimated to save 1807 kg of standard coal annually, with an investment payback period of 7.6 years. These results indicate that the constructed zero-energy ecological toilet system is suitable for cold areas and can provide a new way for toilet renovation in cold and dry areas.
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