In this study wood decay fungi Trametes versicolor and Pleurotus ostreatus were used for pretreatment of chicken manure. We monitored the production of biogas during the fermentation of chicken manure with sawdust and wheat straw which was previously overgrown with fungi. The pretreatment started by preparing the mixtures of chicken manure with sawdust and wheat straw overgrown with fungi in the ratio 50:50. For the control ordinary wheat straw was used instead of wheat straw overgrown with fungi. The pretreatment time was 0, 5, 9 and 14 days. After pretreatment, the inoculum was added to the mixtures in the ratio 50:50. All fermentation experiments were conducted in duplicate. The fermenters were thermostated for 21 days at the temperature of 42 ?C. The amount of produced biogas was measured with water displacement technique. The concentrations of CH4 and CO2 were determined using GC coupled with TCD detector. We made the comparison between the amount of produced biogas, concentrations of CH4 and CO2 regarding different pretreatment time with different fungi and ordinary wheat straw.
F.09 Development of a new technological process or technology
COBISS.SI-ID: 21655318This report presents a description and results of the research project in the following areas: a) cultivation of non-food plants, and optimization of input substrates and the ratios between them for biogas production process, b) pretreatment of substrates by wood decay fungi, measurements of biogas production from various combination of chicken manure and various non-food substrates, options for further processing of solid and liquid fermentation residues (microreaction system for processing methane into (bio)synthesis gas, solid fertilizer biochar+digestate, liquid concentrated nitrogen fertilizer), c) water integration and absorption cooling design, d) mathematical model for optimization of biogas process integrated within the entire supply chain of business system, e) development of a holistic approach based on process systems engineering with optimization for improving efficiency and competitiveness of renewables-based processes.
F.23 Development of new system-wide, normative and programme solutions, and methods
COBISS.SI-ID: 22187798Within this work we investigated if the replacement of corn silage with other energy crops, such as corn stover, would produce similar amounts of biogas, and what would be the economic effect of replacing corn silage. The study was carried out in different proportions of poultry manure with beddings and corn silage or stover. The experiments were conducted where corn silage was completely replaced with corn stover, silage was only partly replaced with corn stover, and also where only poultry manure with beddings was used without the addition of co-substrates. As a reference we used the data from the existing biogas plant, which also uses maize silage for its production. In order to create the conditions as close as possible to those in the biogas plant, we used their inoculum in all the experiments. During the process of anaerobic digestion, we measured the amounts of produced biogas, the quantity of methane and carbon dioxide (CO2), and the quantity of produced digestate. We extrapolated the given results to the industrial level and performed a comparative economic analysis of the raw material costs. We have obtained promising results from the perspective of the biogas produced as well as from the economic perspective. We have noticed that even partial replacement of silage with cheaper corn stover results in significant improvements, not only in terms of higher yield of produced biogas, but also from the viewpoint of raw material cost.
F.10 Improvements to an existing technological process or technology
COBISS.SI-ID: 19927830The possibilities of integration of water and energy consumers in a poultry meat production company were studied in this dissertation. Water integration was performed for different types of facilities using a pinch analysis method. Energy integration of cooling system was performed using Aspen Plus process simulation software. In water integration analysis, water networks where designed by using data provided by the company. Proposed water networks would reuse water between processes so that freshwater usage and wastewater production would reduce. The cost of fresh water and wastewater will therefore reduce too. In energy integration, a change of compression cycle-based cooling system with absorption-based cooling system was proposed to lower the costs of cooling. Both, compression and absorption-based cycles were simulated. We also simulated a heat pump for waste heat reuse. Different thermodynamic models were also tested and compared. Water integration analysis results showed that the proposed changes reduce the freshwater usage and the cost of freshwater. Simulation results also showed that the implementation of absorption-based cooling system with added heath pump for waste heat reuse reduce the cost of cooling. Results of thermodynamic model comparison show that the choice of thermodynamic model did not have an important influence on the results of the simulation.
F.10 Improvements to an existing technological process or technology
COBISS.SI-ID: 22103830Large cooling or freezing requirements at sub-ambient temperatures can represent a significant cost to company. Typical representative of an industry with high cooling demand is the food sector with high storage demands. A promising solution for cooling is the absorption chilling, which utilizes heat for driving the cooling cycle instead of electricity. In this work a thermodynamic approach for the evaluation of absorption chilling, integrated to a process, has been developed. First, the model for estimation of absorption chilling was developed. Deriving the streams can be done after obtaining the heat duties of each unit constructing the absorption chiller. The integration of absorption chiller is evaluated by application of Grand Composite Curve and the derived streams of absorption chilling cycle. Three different options of integration was analysed: i) above Pinch, ii) below the Pinch, and iii) across the Pinch. The analysis indicates that the best integration can be achieved, when an absorption chiller is placed across the Pinch releasing all the heat above the Pinch. There are still benefits, when integration is performed entirely below the Pinch. However, placement of an absorption chiller entirely above the Pinch or integrating the chiller across the Pinch so that only a small part of its heat is released and used above the Pinch is inappropriate. It increases hot and cold utility consumption at expense of additional investment.
F.23 Development of new system-wide, normative and programme solutions, and methods
COBISS.SI-ID: 19683350