湿解处理木质纤维类废物的实验研究

Experimental study on lignocellulosic residues by hydrothermal degradation

湿解是环境友好的新型有机废物处理技术。在小型湿解实验装置中，对草坪草进行了湿解实验，引入了能够综合反应操作温度和停留时间对湿解反应影响的反应强度参数，运用木质纤维素固体基质半纤维素、纤维素和木质素定量分析程序，灼烧法，容量法，浸提法和高效液相色谱等考察了在不同反应强度参数下，湿解对固体产物和液体产物的影响。结果表明，随反应强度的增加，湿解后固体产物减重的现象增加；半纤维素残留量明显下降，纤维素由于其复杂的晶体结构，其残留量变化差别不大，但有约70％左右的纤维素被降解；有机质转化率逐渐增加；木质素质量分数由于湿解产物的重聚与缩合而高于原料中木质素分数浓度。在研究选用的反应强度参数3．16-4．63范围内，湿解产物腐殖化率大于0．8，有较好的腐熟度。湿解液体产物的分析表明：当反应强度增加时，总可溶性糖的质量浓度先增加而后下降，乙酸和糠醛一直呈增加的趋势。

Hydrothermal treatment is an environment-friendly technology for the treatment degradable organic wastes. In this study, The hydrothermal degradation （HTD） experiments of lawn-grass were carried out in the pilot digestor. A severity parameter which combines time and temperature was introduced. Quantitative analysis procedure of lignoceUulose solid substrate： hemiceUulose, cellulose and fignin, ignition method, volumetric method, soak extract method, and fiquid chromatograph were utilized to study the effect of the HTD on sofid and liquid products in different treatment severities. The results show that, with the severity increasing, the weight of the solid products and the hemicelluloses content remarkably decrease, about 70% of the cellulose fraction is degraded for its complex structure, and the conversion rate of the organic matter increases, Whereas the liguin content of the treated products is higher than the initial lignin content of the original material owing to the degradation products copolymerizing. Moreover, the humification ratio is more than 0.8 in the range of measured treatment severities, which suggests that lawn-grass after hydrothermal treatment had a higher degree of maturity. At the same time, the soluble sugars increase until the treatment severity is over 4.05, however, the acetic acid and furfural content always increases in the liquid products.