Evaluation of the effect of tween-80 and its additive amount on the maturity of cassava residue compost

Cellulose, hemicellulose, and lignin interweave to form a dense network structure that makes lignocellulosic biomass difficult to degrade. Tween-80 is a non-ionic surfactant that can be used to promote microbial growth and increase the rate of microbial metabolism in compost. In this study, different doses of Tween-80 were presented as additives in the composting process to reduce the composting time and improve the maturity of the compost. The composting trial was conducted in a 10 L reactor for 46 days. The results showed that the addition of the chemical surfactant Tween-80 increased the temperature in the composting process and could effectively promote the degradation of lignocellulose and reduce phytotoxicity. During the composting process, the microbial population showed exponential growth followed by a gradual decline. At the end of composting, Tween80 added at 0.35% reduced the C/N ratio to 9.61, much lower than that of the CK group at 12.3. Meanwhile, the degradation rates of cellulose and hemicellulose increased by 2.76% and 7.86%, respectively. Toxicity experiments on compost products also proved that the seed germination index of compost with 0.35% Tween-80 addition increased to 98.57%, which is 17.33% higher than that without the addition. FT-IR and TG experiments showed that the addition of Tween-80 could effectively accelerate the composting process and promote the rapid maturation of the heap. In conclusion, the addition of 0.35% Tween-80 was most conducive to promoting the rapid decomposition of organic matter in cassava residue compost and improving the maturity of the heap.

Automated summary

The addition of the chemical surfactant Tween-80 increased the temperature in the composting process and effectively promoted the degradation of lignocellulose and reduced phytotoxicity. Adding 0.35% Tween-80 significantly reduced the C/N ratio, accelerated the degradation of cellulose and hemicellulose, and improved the seed germination index of compost products.