9. Серафимова Е., В. Стоянов, Й. Пеловски, В. Петкова, Механични изпитвания на киселинно третирани смеси от птичи екскременти със сярна киселина, In: Proc. of 15th INTERNATIONAL SCIENTIFIC CONFERENCE VSU'2015, Editors: V. Stoyanov and D. Partov, vol. 1, 4–5 June 2015, Sofia, Bulgaria ISSN: 1314-071X, (2015), v.2, 462-468

Abstract: Various great quantities of solid wastes are generated from different industries. During last 100 years generated solid are more than those from the previous period of human civilization. The global objective is to minimize wastes bot mostly of wastes are deposited, creating long term negative effects for human health. One promising direction for solving the problem is to create compositions containing poultry excrement and ash from the biomass, which is acid -treated with sulfuric acid.
To study these compositions several samples were produced at a specific homogenization then left to rest for several days. The process of production/granulation changes the physical properties of the mixture and to study it the static strength of the granules are examined. The obtained results show that the static strength of the granules in different mixtures vary, but exceeds the requirements of the standard, i.e. the tablets were prepared with good adhesion, pelletizing ability and excellent strength characteristics. The data analysis shows that the sufficient compression strength of the tablet may be achieved at wide range of initial moisture content, which indicates that it is possible to create compositions with different ratio of components.