Forming and Degradation Mechanism of Bowl Seedling Tray Based on Straw Lignin Conversion

Abstract

In response to the problems of low straw utilization efficiency and poor returning effect in Northeast China, this paper takes rice straw containing cow dung as the experimental material, and according to the characteristics of lignin glass transformation of the material, proposes a new method to prepare biomass seedling trays. The seedling trays prepared by this method can meet the needs of corn seedling cultivation and transplantation. To study the molding mechanism, scanning electron microscopy and a universal testing machine were used to compare the changes in the internal structure and mechanical properties of the regularly- and hot-compressed seedling trays before and after seedling raising. The results show that the material with water content of 23% has the best hot-pressing effect. The forming mechanism is: that the strength of the molded seedling tray resulted from the mechanical setting force of the multilayered stem fibers with a mosaic structure within the seedling tray. The adhesion and wrapping by lignin prevented water penetration from damaging the multilayered stem fibers and slightly improved their strength. The seedling tray made of straw and manure was completely degraded over 40 days, and the straw degradation rate was improved. This method can increase the overall quality and benefits of straw, providing a foundational reference for high-quality and high-efficiency straw utilization.

Keywords

• straw return-to-field
• molding mechanism
• molding of seedling tray
• straw degradation