Search

Lignin, an abundant biopolymer derived from plants, is a green binder for stabilizing soil. This study investigates the thermal conductivity of lignin [e.g., sodium ignosulfonate (SL), calcium lignosulfonate (CL), and lignin fiber (LF)] and lignin-stabilized loess. The effects of the source of loess samples, lignin content, curing time, water content, and dry density on the thermal conductivity of the stabilized soils were experimentally evaluated. Furthermore, mineralogy and microstructure of the stabilized loess were investigated using X-ray diffraction, scanning electron microscopy, and mercury intrusion porosimetry tests to provide insights into the mechanisms of lignin-based soil stabilization. The test results showed that lignin had a lower thermal conductivity than water and soil minerals. The addition of lignin reduced the thermal conductivity of loess, with CL and SL causing a slightly greater reduction than LF. Mixing lignin with loess did not generate new crystalline material. The incorporation of CL and SL altered the microstructure of loess, resulting in a densely packed structure with distinct particle bonds and intra-aggregate pores. In contrast, LF provide microscale reinforcement for the soil particles, presenting a loose structure with dominant interaggregate pores. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Low-rank coal (LRC) pyrolysis assisted by biomass can realize the clean and efficient conversion utilization of LRC. The gas and tar characteristics obtained from co-pyrolysis of apple branch (AB) and LRC at different stages were studied with TG-FTIR and Py-GC/MS. It was found that the co-pyrolysis process could be divided into four stages, and the weight loss rate of AB+LRC was 24.03% in the second stage (194.60–404.63 °C), lower than the calculated value. However, the third stage (404.63–594.33 °C) weight loss rate was 13.33%, higher than the calculated value. The content of volatile products increased during co-pyrolysis, resulting in a higher total weight loss rate than the calculated value. There was a synergistic effect between AB and LRC. Aromatic hydrocarbon release intensity in co-pyrolysis products was significantly enhanced in the second and third stages, and it was stronger than that of pyrolysis alone; in contrast, the release intensity of gaseous products was weaker than that of pyrolysis alone. In co-pyrolysis tar, the content of monocyclic and bicyclic aromatic hydrocarbons was increased. The C<10 component was 86.48%, higher than the calculated value of 12.68%. The proportion of aromatic hydrocarbons and phenols increased significantly compared with the calculated value. [ABSTRACT FROM AUTHOR]