Damjan G. Vučurović

Process model and economic analysis of ethanol production from sugar beet raw juice as part of the cleaner production concept.

The batch fermentation process of sugar beet processing intermediates by free yeast cells is the most widely used method in the Autonomous Province of Vojvodina for producing ethanol as fuel. In this study a process and cost model was developed for producing ethanol from raw juice. The model can be used to calculate capital investment costs, unit production costs and operating costs for a plant producing 44 million l of 99.6% pure ethanol annually. In the sensitivity analysis the influence of sugar beet and yeast price, as well as the influence of recycled biomass on process economics, ethanol production costs and project feasibility was examined. The results of this study clearly demonstrate that the raw material costs have a significant influence on the expenses for producing ethanol. Also, the optimal percentage of recycled biomass turned out to be in the range from 50% to 70%.

Assessment of the effectiveness of policy implementation for sustainable energy development in Southeast Europe

Using solely economic indicators as a measure of development as a whole is no longer justified and acceptable. The survey covered 11 countries in the region of Southeast Europe—in the region for which indicators of sustainable energetic development were defined. The authors propose a specific way of expressing their needs for treatment using the method of weight coefficients. The results indicate that the efficiency of energetic policy in the region varies widely. Countries at higher level of economic development record a high dependence on energy imports. Countries in the region at a similar stage of development show different energy consumption per capita and the different intensity of energy production from renewable resources. Research shows that energetic efficiency policies in the region, apart from the available energy resources, largely depends on the degree of economic development that a country wants to achieve. Countries at lower level of development show higher degree of sustainability in terms of energy management and vice versa. The most favorable situation was observed in Bulgaria. Negative trends were observed in Greece and Hungary, while in Slovenia the indicators were on the border of sustainability. Data used for research refer to the year 2010.

Exploitation of biogas power plant—Clean Development Mechanism project, Vizelj, Serbia

This case study of biogas power plant is designed in accordance with the existing energy policy that recognizes producers of energy from renewable sources as producers with privileged status and guarantees the purchase of energy at subsidized prices. The investor company revised its own energy policy and aligned it with the priorities of sustainable energy policy of Serbia. The paper presents an analysis of biogas power plant output (electrical and thermal energy), balance, sale, and potential prices on the market that are consistent with the incentives of energy policy of Serbia. In addition, special emphasis is given to the revenues that a biogas power plant realizes by using another mechanism of energy policy, which promotes gaining revenues by reducing pollution of the atmosphere. The authors also show the procedure, costs, and expected effects from the qualification of this power plant project for the Clean Development Mechanism project categories. Investing in a biogas power plant in Serbia costs 95...

Environmental biotechnology for the treatment of waste effluents from biofuels production

Bioethanol, biodiesel and biogas represent very significant alternatives to fossil fuels in order to reduce carbon- dioxide emissions, so there is a need to develop energy efficient technologies, equipment and waste management procedures to make production profitable by reducing production costs. One way to accomplish this is to solve the problem of waste effluents by using them to obtain high-value products. All biotechnological processes are energy intensive to some extent, so saving energy becomes one of the main goals of all biotechnological processes in addition to preserving the environment and the management or reuse of waste. The availability of waste effluents from the production of biofuels, such as distillery stillage and crude glycerol, will increase over the next few years due to the growth of the biofuel industry and will provide a great possibility for the biotechnological production of high-value products.