Energetic Valorization of Poultry Waste: The Sideview

The poultry farming waste, as a mixture of dropping and bedding material is usually used as a fertilizer in agriculture because of their richness of mineral materials. However, expanded production of broilers, with decreased availability of agricultural land and potential negative effects of long-lasting application of such a material on land, encourage searching for alternative ways for use of this materials. Generally speaking, there are two ways, beside of abovementioned: (1) exploitation of poultry waste in compost production and (2) its use for energy production. This paper exposes the overview of state-of-the-art (techniques and equipment) within the field of energetic valorization of poultry waste by direct thermal methods, and discusses various aspects of mentioned practices

Wastewater sludge conditioning with flocculant-NaCl-straw to improve sludge dewaterability

One of the major improvement points in wastewater treatment processes is sludge treatment. The effectiveness of existing sludge treatment processes is highly limited due to poor dewaterability and compressibility of sludge. In this paper, a new sludge conditioning method was studied. The results show that combining NaCl and straw powder with commercial flocculant significantly improves sludge dewaterability and reduces moisture content, while increasing heat value. Adding NaCl in 0.25M dosage and 50% straw powder (dried and sieved to 0.125 – 0.063 µm) resulted in significant reduction of specific resistance to filtration and sludge moisture content. The results also suggest that it would be possible to partially substitute the flocculant with less expensive conditioners, which could potentially reduce the cost of sludge dewatering

Investigation of the influence of MgO and CaO content on the quality of technical ceramics

In this paper, the influence of MgO and CaO content on the quality of technical ceramics (which originally represents the  Al2O3 - SiO2 - CaO - MgO system) has been investigated. Therefore, quality tests were performed on samples where the contents of CaO and MgO were taken as variable values. Based on the obtained test results and their analysis, certain characteristics of ceramics are defined with the different percentages of individual oxides content in 98.2 - 99% Al2O3

Mogućnost primjene hidratiziranog vapna kao katalizatora u procesu metanolize suncokretova ulja

Postojeći komercijalni procesi dobivanja biodizela uglavnom se zasnivaju na homogenoj bazno kataliziranoj metanolizi biljnih ulja. Najčešće se kao katalizatori primjenjuju NaOH i KOH i NaOCH3. U ovom radu istraživana je mogućnost primjene hidratiziranog vapna, komercijalnog proizvoda koji se prije svega primjenjuje u građevinarstvu, kao katalizatora u procesu metanolize suncokretova ulja. Ispitivan je utjecaj procesnih parametara; mase katalizatora, omjera ulja i metanola te duljine trajanja na prinos metilnog estera i na osnovne karakteristike dobivenog biodizela. Rezultati dobiveni istraživanjima u okviru ovog rada pokazuju da se hidratizirano vapno može upotrebljavati kao učinkovit, jeftin i ekološki prihvatljiv katalizator za metanolizu suncokretova ulja

Recurrent water from slag and fly ash disposal ponds as a medium for carbon capture and storage

Due to the increased use of fossil fuels and industrial production, the concentration of carbon dioxide in the atmosphere increases, causing greenhouse effect and, consequently, climate change. Stationary CO2 sources like coal power plants produce the bulk of the world’s CO2 emissions. Electricity and heat plants and other fuel transformation activities account for 40% of total global CO2 emissions. Therefore, great interest in the possibilities of CCS systems to reduce CO2 emission is evident, either through removal or reduction measures. The experimental part of this paper deals with the determination of the potential of alternative media for use in CCS technologies, describing the lab-scale investigation. The role of alternative media in that context has been as-signed to recurrent water from fly ash and slag disposal pond Jezero II of Power Plant Tuzla. When choosing an alternative medium for CCS applications, the following features were considered: that the medium currently has a negative impact on the environment; that the medium is available in sufficient quantities; that the medium has a low price and that its final disposal causes costs. Hence, the ability of the selected media (recurrent water) for CO2 capture has been confirmed and its capacity in that context roughly determined

Recurrent water from slag and fly ash disposal ponds as a medium for carbon capture and storage

Due to the increased use of fossil fuels and industrial production, the concentration of carbon dioxide in the atmosphere increases, causing greenhouse effect and, consequently, climate change. Stationary CO2 sources like coal power plants produce the bulk of the world’s CO2 emissions. Electricity and heat plants and other fuel transformation activities account for 40% of total global CO2 emissions. Therefore, great interest in the possibilities of CCS systems to reduce CO2 emission is evident, either through removal or reduction measures. The experimental part of this paper deals with the determination of the potential of alternative media for use in CCS technologies, describing the lab-scale investigation. The role of alternative media in that context has been as-signed to recurrent water from fly ash and slag disposal pond Jezero II of Power Plant Tuzla. When choosing an alternative medium for CCS applications, the following features were considered: that the medium currently has a negative impact on the environment; that the medium is available in sufficient quantities; that the medium has a low price and that its final disposal causes costs. Hence, the ability of the selected media (recurrent water) for CO2 capture has been confirmed and its capacity in that context roughly determined

OPTIMIZING PROCESS CONTROL OF THE ANAEROBIC DIGESTION OF ORGANIC MATTER

The proper process control is the key to achieving both environmental and commercial goals of conducting the process of anaerobic digestion. Taking into account that the parameters that can be monitored are quite numerous, and that the monitoring equipment, its installation and maintenance require significant financial resources, it is, from commercial aspect, necessary to minimize the number of parameters to the set of parameters which are necessary but sufficient for the proper conduct of the process to the point after which the further continuation of the process is not economically justified. The paper presents the model developed for determination of the minimum number of parameters to be monitored in order to ensure sufficient quality control of this process and describes its validation through the laboratory test

Thermal pretreatment of cattle manure for enhancing biogas production

The low degradability of waste materials containing lignocellulosic material is one of the factors that hinder the production of biogas. The increased need for advanced techniques in the anaerobic digestion process has led to the use of different pretreatment raw materials prior to the anaerobic digestion process in order to increase the yield of biogas. In order to maximize the yield of biogas from cattle manure in a mixture with waste sludge, the anaerobic digestion process was performed at mesophilic conditions for 54 days. As pretreatment, the thermal treatment of cattle manure at temperatures of 55 and 70°C was applied. The highest biogas production was obtained in the sample of cattle manure, previously treated at 70°C (M70), while the lowest was recorded in the control sample M. The specific biogas production in relation to the input quantity of volatile organic matter had the highest value in sample M70 and the lowest in the control sample. Overall results have shown that the thermal treatment of cattle manure before the anaerobic digestion process can increase both yield and biogas quality