Development and application of the compression frictional treatment method for sterilizing and valorizing organic waste

ABSTRACT

Confined animal feeding operations are producing large amounts of organic waste with large fractions being mixtures of manure and sawdust. On one hand, the inhomogeneity of the material and the high water content restrict the optimal application of thermal treatment methods. On the other hand, the high concentration of bacteria in these mixed waste streams is an issue of concern. This study introduces a novel process for treating manure and woody biomass mixtures and upgrading them into valuable products. It is defined as compression frictional treatment (CFT) and takes place continuously in a rotary compression unit. Fresh poultry droppings and fresh anaerobic digester offal from a cattle feedlot were processed by means of CFT. Moisture was decreased by 52% and heating value was increased by 27% for treated poultry litter. The corresponding values were 63% moisture decrease and 25% increase for the heating value of cattle manure. On the aspect of bacteria reduction, the Escherichia coli and the Enterobacteriaceae family of bacterium were reduced by 94% and 91%, respectively.

KEYWORDS:

• Pre-treatment
• frictional pyrolysis
• densification
• bio waste
• steam explosion

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Stergios Vakalis http://orcid.org/0000-0003-0774-0506