# Thermo-Chemical Treatment for Carass Disposal and the Application of Treated Carcass as Compost
## 4 Conclusions  
The mechanized thermo-chemical treatment process developed in this study treats animal carcasses sequentially. The process includes crushing, quicklime amendment and mixing, heat treatment (200-500 \({}^{\circ}\)C), sawdust amendment and mixing, and ejection. Compared to incineration, rendering, and anaerobic digestion, the thermo-chemical treatment method has the advantages of rapid treatment of carcasses as well as no secondary pollution such as soil and groundwater contamination associated with livestock burial. Since the device is mounted on a truck and moved to the field to treat the carcass, the risk of the spread of disease from transportation is avoided. Dixoxins (a problem during incineration) were not detected, and the concentration of VOCs was within the air pollutant emission standards. The mechanized thermo-chemical treatment process was applied to treat the carcasses of chickens and pigs buried in the storages of fiber-reinforced plastics. The thermo-chemical treatment method for treating the carcass in burial sites is economical with high benefit/cost ratios. The legal criteria for compost such as heavy metal concentration, the contents of C, N, and P, and the absence of _E. coli_ and _Salmonella_ were satisfied, but the germination index was not suitable. Owing to its low germination index, when the treated carcass product was used to compost low nutrient soil, lettuce growth was poorer than in low nutrient soil without the treated carcass. The use of zeolite was suggested for adsorbing ammonia, which was identified as an important pollutant in the burial site. Since zeolite was effective in adsorbing the ammonia eluted from the treated carcass, nitrogen can be more effectively supplied to plants by adding zeolite to the product before it is used to amend the soil. Mechanized thermo-chemical treatment processing is an excellent technique for treating animal carcasses, although composting of the product is required before it is used to amend the soil for plant growth.  
Conceptualization, S-J.P. and D.-H.K.; methodology, J-I.L. and E.-J.C.; validation, J-J.L.; formal analysis, J-I.L. and E.-J.C.; data curation, J-I.L. and C.-H.L.; visualization, S-Y.H.; supervision, S-J.P. and C.-G.L.; writing--original draft preparation, J-I.L., F.N.L., and S-J.P.; writing--review and editing, S-J.P. and C.-G.L. All authors have read and agreed to the published version of the manuscript.  
This work was also supported by Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry, and Fisheries through Animal Disease Management Technology Development Program, funded by MAFRA (Grant No. 118095-2).  
Not applicable.  
The data presented in this study are available on request from the corresponding author. The data are not publicly available due to that this study was conducted with financial support from the Korean government.  
The authors declare no conflict of interest.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Source** & **DF** & **Sum of Squares** & **Mean Square** & **F Value** & **Pr ¿ F** \\ \hline Sol & 2 & 19,724.2 & 9862.1 & 3691.4 & \textless{}0.0001 \\ Time & 7 & 268.8 & 38.4 & 14.4 & \textless{}0.0001 \\ Sol-Time & 14 & 265.4 & 18.9 & 7.1 & \textless{}0.0001 \\ \hline \hline \end{tabular}
\end{table}
Table 5: ANOVA for NH\({}_{4}\) concentrations eluted from the treated carcass with regard to zeolite amendment and elution time.