Department of Process and Environmental Engineering, Faculty of Mechanical Engineering, Opole University of Technology, ul. Mikołajczyka 5, 45-271, Opole, Poland.
Environ Sci Pollut Res Int. 2021 Jul;28(26):34290-34299. doi: 10.1007/s11356-021-12848-3. Epub 2021 Feb 26.
In the paper, results of drying biofuels from sewage sludge using solar energy are presented. Drying rates of biofuels made from sewage sludge and coal slime (PBS), sewage sludge and meat and bone meal (PBM), and sewage sludge and sawdust (PBT) with 15-mm and 35-mm granule particle size were studied. Tests were performed in a solar greenhouse dryer equipped with a specially designed mixing system. Experiments were aimed at determining the drying time of biofuels under various weather conditions in the southwestern part of Poland. In summer, in order to determine the best conditions for drying, tests were performed using various parameters, i.e., layers of various thickness, such as 5, 10, and 20 cm, and various mixing intensity (no mixing, mixing 3 and 5 times/day). In spring and the fall, 10-cm thick layers combined with 5 times mixing of fuels per day were used. The performed tests demonstrated that it is beneficial to dry fuels in 10-cm thick layer. In spring and the fall, PBS and PBM biofuels laid out in layers with just such thickness showed moisture content reduced to less than 10% after 8 days, while the PBT biofuel reached the same level after 14 days. In summer, the same result may be obtained for all the biofuels after 4 days on average. The presented original method of solar drying of biofuels obtained from sewage sludge and other waste may be used in wastewater treatment plants which process sewage sludge into fuels without incurring any additional costs for supplying heat.
本文介绍了利用太阳能干燥污水污泥衍生生物燃料的结果。研究了粒径为 15mm 和 35mm 的污水污泥与煤泥（PBS）、污水污泥与肉骨粉（PBM）和污水污泥与木屑（PBT）制成的生物燃料的干燥速率。测试在配备专门设计的混合系统的太阳能温室干燥器中进行。实验旨在确定在波兰西南部各种天气条件下生物燃料的干燥时间。在夏季，为了确定最佳干燥条件，使用各种参数（例如 5cm、10cm 和 20cm 等不同厚度的层以及不同的混合强度（不混合、每天混合 3 次和 5 次）进行了测试。在春季和秋季，使用 10cm 厚的层并每天混合 5 次燃料。进行的测试表明，将燃料干燥成 10cm 厚的层是有益的。在春季和秋季，仅以这种厚度分层布置的 PBS 和 PBM 生物燃料在 8 天后的水分含量降低到 10%以下，而 PBT 生物燃料在 14 天后达到相同水平。在夏季，所有生物燃料的平均干燥时间约为 4 天。本文提出的从污水污泥和其他废物中获得的生物燃料的太阳能干燥原始方法可用于污水处理厂，将污水污泥转化为燃料，而无需额外支付供热费用。
