• Energy Research

The processing of meat industry waste into meat-and-bone meal (MBM) provides the opportunity to use it as fertiliser in the cultivation of agricultural crops. This study was conducted in the years 2014–2017 at the Experimental Station in Tomaszkowo, Poland to assess MBM effects on yield and quality of maize cultivated for grain. An example of the effective use of nutrients contained in MBM applied at doses of 2.0 and 3.0 t ha is the cultivation of maize in 2016, which was affected by favourable weather conditions. The effect of the accumulation of MBM doses and, consequently, the provision of a greater amount of nutrients ensure sufficient amounts to obtain yields, greater than those provided by mineral fertilisation only. The macronutrient concentration in the maize grains following the application of MBM was similar to the composition of the grains of maize fertilised with mineral N, P and K fertilisers. With the MBM, micronutrients are introduced in amounts that are able to satisfy plants with these components, yet this study failed to demonstrate any effect of increased MBM doses on the concentration of the analysed elements in the maize grains.

Pneumatic separation is one of the available methods for cleaning seed mixtures. Variously shaped seeds, including spherical (vetch), elongated (wheat), and pyramid-shaped seeds (buckwheat), were analyzed in this study. A seed mixture containing 80% of main crop seeds and 20% of other crop seeds imitating impurities was separated in a pneumatic separator with the shape of an inverted cone in a stream of air. The regression equations describing the separation efficiency of the main crop seeds and other crop seeds imitating impurities (η) and the separation efficiency index (ε) were characterized by high and very high fit to empirical data. The coefficient of determination for the analyzed seed mixtures ranged from 0.71 to 0.99. The conical separator supported effective separation of seed mixture components in a stream of air.

Organic waste can provide an alternative to synthetic fertilisers for maintaining productivity with limited environmental impact. Our research evaluates the potential use of processed animal waste in corn fertilisation, which may represent a partially closed nutrient cycle of importance in a sustainable agricultural system. The objective of this study was to evaluate the quantity and quality of fat obtained from corn grain fertilised with meat and bone meal (MBM) produced from animal waste. A static field experiment using MBM was conducted at the Experimental Station in Tomaszkowo (53°71′ N, 20°43′ E), Poland. The field experiment was conducted in 2014–2017 with continuous corn cultivation. The course of weather conditions in the years of this study influenced the fat content, with the lowest amount found in 2016. The application of fertilisers in the form of MBM and mineral fertilisation resulted in a slightly lower fat content compared to the variant without fertilisation. The application of mineral fertilisers and MBM influenced an increase in the content of the predominant C18:2 acid compared to the variant without fertilisation, while the opposite was shown for C18:1 cis-9 acid. The fertiliser variants are most correlated with fat yield and total polyunsaturated fatty acids. The fertiliser variants in their effects on fat yield, fat content, fatty acid profiles, and their ratios can be divided into three groups, which were related to the effects of organic fertilisers during the years of this study. The use of meat and bone meal as fertilisers cannot be regarded as a factor in increasing the fat content of corn grain. Meat and bone meal applied over several years to the same field in the quantities required to achieve optimum yield can be an element that shapes fatty acid profiles.