Human waste treatment using renewable energy is one of the emerging interests to minimize adverse environmental impacts. In the present study, the concept of treating urine and faeces separated from blackwater originated from toilets, using indigenously developed solar thermal systems, namely tilted partitioned basin solar distiller (TPBSD) and stepped solar dryer (SSD), respectively were proposed and experimented. The performance of solar thermal units was monitored with respect to temperature, solar radiation, treated water and solids quality, environmental and cost benefits. TPBSD produced a maximum yield of 4.67 ± 0.99 L/m²d with a thermal efficiency of 49% during urine distillation. The overall efficiency of solar distiller in terms of recovery varied from 50 to 60%. The condensate quality was found to be good and can be reused for domestic purposes. Similar to the distiller, the SSD performed well for theremoval of moisture content (95.8%) and pathogens (>98.9%). The dried matter was completely free from microbial content and rich in nutrients, which can be used as a natural fertilizer. The kinetics drying was modeled using different thin layer models and among that Page model predicts well with the experimental data. Moreover, the enviro-economic analysis indicated that the TPSBD and SSD could mitigate 23.8 and 6.47 tons of CO₂ emissions, respectively, during its 20 years of life span. The energy payback period is 1.97 and 5.19 years, with 300 clear days for TPSBD and SSD, respectively. The obtained results from this research confirm and justify the capability of solar thermal systems as an efficient and viable alternative for human waste treatment.

使用可再生能源处理人类废物是减少不利环境影响的新兴利益之一。在本研究中，提出并实验了利用本土开发的太阳能热系统，即倾斜分隔盆太阳能蒸馏器 (TPBSD) 和阶梯式太阳能干燥器 (SSD)，处理源自马桶黑水的尿液和粪便分离的概念。太阳能热装置的性能在温度、太阳辐射、处理过的水和固体质量、环境和成本效益方面受到监控。TPBSD 产生的最大产量为 4.67 ± 0.99 L/m ²d 在尿液蒸馏过程中的热效率为 49%。太阳能蒸馏器在回收方面的整体效率从 50% 到 60% 不等。发现冷凝水质量良好，可重新用于家庭用途。与蒸馏器类似，SSD 在去除水分 (95.8%) 和病原体 (>98.9%) 方面表现良好。干燥后的物质完全不含微生物，营养丰富，可作为天然肥料。使用不同的薄层模型模拟干燥动力学，其中 Page 模型可以很好地预测实验数据。此外，环境经济分析表明，TPSBD 和 SSD 可以减少 23.8 和 6.47 吨的 CO ₂分别在其 20 年的寿命期间排放。能源回收期分别为 1.97 年和 5.19 年，TPSBD 和 SSD 分别为 300 天。从这项研究中获得的结果证实并证明了太阳能热系统作为人类废物处理的有效和可行替代方案的能力。