# Application of frass from black soldier fly larvae treatment of cattle dung in pulp and papermaking

## TL;DR

This study explores using frass from black soldier fly larvae, which digest cattle dung, as a material for pulp and papermaking.

## Contribution

The novel use of BSFL frass as a nonwood fiber source for soda pulping and paper production is demonstrated.

## Key findings

- Frass has high holocellulose (67.37%) and α-cellulose (48.00%) content suitable for pulping.
- Optimal pulping conditions (7% NaOH, 75 min) achieved a 34.06% accepts ratio and improved strength.
- Frass pulp blended with TOCC met cardboard ring crush index standards.

## Abstract

Cattle dung treatments in Taiwan have developed a process called Black soldier fly larvae (BSFL) treatment, which can digest cow dung and generate the frass (larvae drops), the residue fiber in cow dung. This study aims to assess frass for its potential in pulp and papermaking, considering its chemical compositions, appearance, and fiber morphology, and also evaluate its suitability for pulping by soda method to create added value. The frass exhibits favorable material properties for pulping and papermaking, including a high holocellulose (67.37%) and α-cellulose (48.00%) content, along with a lower ash content (4.61%); the microstructure and surface mesoporous pores benefit for pulping; and the nonwood-fiber-like fiber morphology. The pulping experiment shows that 7% NaOH and 75 min of pulping conditions result in proper disintegration of fiber, and the highest accepts ratio (34.06%). The NaOH causes fiber disintegration during pulping, resulting in a higher strength property of the handsheet. The frass pulp blended with TOCC can achieve the ring crush index standards required for cardboard products. In summary, the frass from BSFL treatment of cattle dung can be utilized in pulp and papermaking to enhance circular utilization value.