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Composting is among the most effective integrated waste management strategies used to recycle sewage sludge (SS) waste and generate a useful product. An encapsulated lifting system is a relatively new industrial-scale composting technology. The objective of this study was to evaluate the effectiveness of composting dewatered stabilized SS mixed with green waste using this new technology. The composting process was monitored by changes in the physico-chemical properties, UV-visible spectra, and fourier transform infrared (FTIR) spectra. The composting temperature was steady in the thermophilic range for 24 and 12 d in the intensive and maturation phases, respectively, which fulfilled the disinfection requirement. Moreover, the temperature increased rapidly to 76.8°C within three days, and the thermophilic temperatures peaked twice and lasted longer than in traditional composting, which accelerated SS degradation and decreased the composting period necessary to obtain mature compost. FTIR spectroscopic analysis showed a diminished in methyl group derived from methylene C-H aliphatic groups because of organic matter degradation by microorganisms and an increased number of aromatic chains. The new technology may be a viable and sustainable alternative for SS management that converts waste into compost that is useful as a soil amendment.

Decrease in organic matter of the soil is one of the major threats to soils in Europe and other parts of the globe. Maintaining or increasing organic carbon is a great challenge in agricultural practices. Application of composts and other organic amendments is an important way of compensation of losses of organic carbon at the same time it is solving the placement and recycling of organic wastes and residues.The favorable effect of these amendments on physical, chemical and biological properties has been proved by different studies, however the stability and the rate of the influence is an issue that can be improved. The aim of the presented study was to investigate the effect of carbonates on the solubility of applied organic materials and selected soil parameters. Different biochars, compost and carbonate were added to light textured soil. The pH and E4/E6 rates were studied under laboratory conditions.Beside the increase of soil organic matter content, all studied parameters gave promising results. The decrease in E4/E6 rate suggests that the inorganic carbonates are stabilizing the fresh organic residues and prevent the leaching processes. Improved soil organic carbon stability is very important in light textured soils. Further investigations are undergoing to determine the optimal rate of components and extend the kinds of material available for application.

The application of biochars to improve soils and to mitigate global climate change is a popular research area all over the world, although it is not a new topic. In our study, wood chips char (BC) and animal bone char (ABC) were applied. The pot experiments were conducted under laboratory conditions. 2 grams of rye-grass (Lolium perenne) were seeded into each pot. The following various soil parameters were measured: pH (KCl), AL-P2O5, AL-K2O, total water soluble salt content and organic matter content. The measured parameters from the plant samples were: total-P, total-K and micronutrients. Results show that the negative or positive effect of pyrolysis solids cannot be determined clearly, further experiments are needed.

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