Abstract
Over the past years, the treatment and use of livestock waste has posed a significant problem in environmental engineering. This paper outlines a new approach to application of calcium peroxide (CaO(2)) as a green oxidizer and microbiocidal agent in the treatment of poultry manure. It also presents the application of pretreated waste in improvement of degraded soils in industrial areas. The CCD (Central Composite Design) and RSM (Response Surface Methodology) were employed for optimizing the process parameters (CaO(2) concentration 1.6-8.4 wt %, temperature 5.2-38.8 °C and contact time 7-209 h). The analysis of variance (ANOVA) was used to analyze the experimental results, which indicated good fit of the approximated to the experimental data (R(2) = 0.8901, R(2)(adj) = 0.8168). The amendment of CaO(2) in optimal conditions (8 wt % of CaO(2,) temperature 22 °C and contact time 108 h) caused a decrease in bacteria Escherichia coli (E. coli) in poultry manure from 8.7 log(10) CFU/g to the acceptable level of 3 log(10) CFU/g. The application of pretreated livestock waste on degraded soils and the studies on germination and growth of grass seed mixture (Lollum perenne-Naki, Lollum perenne-Grilla, Poa pratensis-Oxford, Festuca rubbra-Relevant, Festuca rubbra-Adio and Festuca trachypylla-Fornito) showed that a dose of 0.08 g of CaO(2) per 1 gram of poultry manure induced higher yield of grass plants. The calculated indicators for growth of roots (GFR) and shoots (GFS) in soils treated with poultry manure were 10-20% lower compared to soils with amended CaO(2). The evidence from this study suggests that CaO(2) could be used as an environmentally friendly oxidizer and microbiocidal agent for livestock waste.