School of Environmental Science & Technology, Dalian University of Technology, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), Dalian 116024, Liaoning, China.
School of Environmental Science & Technology, Dalian University of Technology, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), Dalian 116024, Liaoning, China.
Waste Manag. 2018 Oct;80:327-338. doi: 10.1016/j.wasman.2018.09.023. Epub 2018 Sep 24.
Recently, bio-drying is becoming a promising method to treat the slurry-type food waste together with recovering refused derived fuels (RDFs). In practice, however, conventional process frequently encountered low temperature and inefficient drying performance due to the low microbial activity and organics degradability. In order to improve bio-drying performance, in this study, an externally thermal assistant strategy was proposed to increase water evaporation and stimulate microbial degradability. Based on this idea, a series of experiments were conducted to establish, evaluate and optimize the thermally assisted bio-drying system. It was found that staged heating acclimation was an effective strategy to obtain a superior thermophilic inoculum with high metabolic activity and microbial consortia. In thermally assisted bio-drying process, an extremely high metabolic activity [cumulative OUR, 38.98 mg/(g TS·h)] was obtained, which was greatly higher than that of conventional bio-drying [19.74 mg/(g TS·h)]. Furthermore, thermally assisted bio-drying exhibited a high water-evaporation capacity as thermal drying (157.9 g vs. 147.8 g), which was 3-fold higher than conventional bio-drying. Heat balance calculation indicated that externally supplying a small fraction (12.94%) of thermal energy triggered conventional bio-drying, thus greatly promoting water removal with high energy utilization efficiency as conventional bio-drying (Q 60.30% vs. 64.62%). In addition, the increased air-flow rates greatly accelerated water removal with high bio-energy efficiencies, especially at 0.8 L·min·kg. The drying effect after 4 days was close to that of 20 days in conventional bio-drying. This research suggests that thermally assisted bio-drying is a promising approach to upgrade conventional bio-drying with high efficiency and low energy cost.
最近，生物干化技术作为一种很有前途的方法，可用于处理浆状型食物垃圾并回收废弃衍生燃料（RDF）。然而，在实际应用中，由于微生物活性和有机物降解性低，常规工艺经常遇到低温和低效的干燥性能。为了提高生物干燥性能，本研究提出了一种外部热辅助策略，以增加水蒸发并刺激微生物降解性。基于这一思路，进行了一系列实验来建立、评估和优化热辅助生物干燥系统。结果发现，分阶段加热驯化是获得具有高代谢活性和微生物群落的优越嗜热接种物的有效策略。在热辅助生物干燥过程中，获得了极高的代谢活性[累积 OUR，38.98mg/（g TS·h）]，远高于常规生物干燥[19.74mg/（g TS·h）]。此外，热辅助生物干燥表现出高的水蒸发能力，与热干燥相当（157.9g 对 147.8g），比常规生物干燥高 3 倍。热量平衡计算表明，外部仅需供应一小部分（12.94%）热能就可触发常规生物干燥，从而大大提高水去除率，并具有较高的能量利用效率，如常规生物干燥（Q 60.30%对 64.62%）。此外，增加空气流速可以大大提高水去除率，并具有较高的生物能量效率，特别是在 0.8L·min·kg 时。4 天的干燥效果接近常规生物干燥 20 天的效果。本研究表明，热辅助生物干燥是一种很有前途的方法，可用于高效、低能耗地升级常规生物干燥。
