Belloulid Mohamed Oussama, Hamdi Hassan, Mandi Laila, Ouazzani Naaila
a National Center for Studies and Research on Water and Energy (CNEREE), University Cadi Ayyad , Marrakesh , Morocco.
b Laboratory of Hydrobiology, Ecotoxicology and Sanitation (LHEA URAC 33) , University Cadi Ayyad , Marrakesh , Morocco.
Environ Technol. 2019 Apr;40(10):1316-1322. doi: 10.1080/09593330.2017.1421713. Epub 2018 Jan 11.
This paper presents a site-specific study of solar drying of wastewater sludge in the region of Marrakesh in Morocco. During the course of the experiments, drying pans (DP) and solar greenhouse drying processes were studied in summer and winter seasons. To simulate the DP process, representative samples were dried in plastic cylindrical plates in ambient conditions, near an Open Greenhouse Sludge Dryer (OGSD) designed and constructed as a tunnel plant. Results showed that the dry solids' (DS) concentration of 80% was reached in only 32 h in summer and 57 h in winter by DP process. The OGSD reached the same concentration in 45 and 65 h in summer and winter, respectively. The important influence of wind speed had a greater effect than the temperature on drying rate. The sludge water evaporation caused a large volume reduction during DP and OGSD processes in both seasons. The removal of total and fecal coliforms during summer experiment was noticeably better in the OGSD, even for Clostridium perfringens. Based on the obtained results, the solar greenhouse drying was practical and beneficial to wastewater sludge management and can be recommended as an alternative to DP in arid climate zones generally, and in Marrakesh particularly.
本文介绍了在摩洛哥马拉喀什地区针对污水污泥进行的特定地点太阳能干燥研究。在实验过程中，对干燥盘（DP）和太阳能温室干燥工艺在夏季和冬季进行了研究。为模拟DP工艺，将代表性样品置于塑料圆柱板中，在环境条件下、靠近作为隧道式装置设计和建造的开放式温室污泥干燥机（OGSD）处进行干燥。结果表明，通过DP工艺，夏季仅需32小时、冬季需57小时就能使干固体（DS）浓度达到80%。OGSD在夏季和冬季分别于45小时和65小时达到相同浓度。风速的重要影响对干燥速率的作用大于温度。在两个季节的DP和OGSD工艺中，污泥水分蒸发导致体积大幅减少。夏季实验期间，OGSD对总大肠菌群和粪大肠菌群的去除效果明显更好，即使对于产气荚膜梭菌也是如此。基于所得结果，太阳能温室干燥对于污水污泥管理切实可行且有益，总体上在干旱气候区，特别是在马拉喀什，可推荐其作为DP的替代方法。
