New Proposal for Sugarcane Vinasse Treatment by Hydrothermal Carbonization: An Evaluation of Solid and Liquid Products

Vinasse is a residue of ethanol production from sugarcane. In view of the problems associated with its disposal, this study aimed to propose a treatment for vinasse by hydrothermal carbonization. The influence of temperature (100 to 200 ºC), acidity (1.7 to 8.3%) and reaction time (12 to 48 h) on the hydrothermal treatment was evaluated, as well the characteristics of the solid (hydrochar) and liquid (process water) products. For the solid product, two hydrothermal carbonization conditions stood out as leading to higher carbonization and yields. These conditions were 200 ºC, 8.3% acidity and times of 12 and 48 h. For the process water, the carbonization reaction at 200 ºC, 8.3% acidity and 48 h produced the highest discoloration and 77% reduction of total organic carbon. Thus, hydrothermal carbonization proved to be an efficient method to treat vinasse, and the hydrochar presents potential for use as fertilizers / soil conditioners, and also the process water after pre-treatment.

酒精废液（vinasse）是甘蔗基乙醇生产过程中产生的副产物。鉴于其处置面临诸多难题，本研究旨在提出一种基于水热碳化技术的酒精废液处理方案。本研究考察了温度（100~200℃）、酸度（1.7%~8.3%）与反应时间（12~48h）对水热处理过程的影响，并分析了固相产物（水热炭hydrochar）与液相产物（工艺水process water）的特性。针对固相产物，有两组水热碳化条件可实现更优的碳化效果与产物产率，分别为温度200℃、酸度8.3%、反应时间12h与48h。针对液相工艺水，当反应条件为200℃、酸度8.3%、反应时间48h时，可获得最高的脱色效率与77%的总有机碳去除率。综上，水热碳化技术是一种高效的酒精废液处理方法，所得水热炭具备用作肥料或土壤调理剂的应用潜力，经预处理后的工艺水同样具备再利用价值。