353 research outputs found

    Dairy waste water treatment by combining ozonation and nanofiltration

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    The aim of this investigation was to examine the applicability of the membrane technique and the effect of preozonation in dairy waste water treatment technology. The best degree of surfactant removal from model anionic surfactant solution by nanofiltration was achieved at 20 degrees C and 40 bar. Investigations on the effects of ozone treatment of the waste water indicated that preozonation decreased the flux and increased the chemical oxygen demand and surfactant removal efficiency. Ozone treatment enhanced the biodegradability of the retentate from 68.8% to 96.4%

    Sustainable Water Use Considering Three Hungarian Dairy Farms

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    Sustainable water management is one of the biggest challenges in the 21st century as availability of fresh water resources is under depletion. Growing population, extreme weather conditions (drought, fire, flood), and increasing global food demand all result in higher water consumption by humans. Assessing qualitative and quantitative deterioration of fresh water supplies is crucial in water scarcity areas. By identifying blue, green and grey water components, water use can be assessed in a more comprehensive way. Water use assessment on a dairy farm is influenced by several factors such as chosen breed, herd size, keeping, feeding and milking technology. Productivity level of milking cows, amount of daily milking and type of litter (straw or liquid manure) have impact on water use by technology and cattle. If these factors are assessed and their proportion within the total water use is identified or calculated, dairy farmers are able to analyze water management precisely and shift to more sustainable solutions. The aim of this research is to analyze and to compare the impact of different keeping systems, i.e., traditional and modern, and milking technologies, i.e., robotic milking system, parallel and polygon parlors, on the water use of dairy farms to give a guide to dairy experts and to find opportunities where water recycling/reuse might be applicable

    Applicability of dielectric measurement in wastewater sludge treatments

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    Our research work focused on the applicability of dielectric measurement methods in wastewater-sludge treatment processes. On the one hand, we wanted to investigate how the soluble chemical oxygen demand (SCOD) - a key characteristic in sewage sludge utilization - changes due to the different sludge pre-treatment processes, and whether these changes are in connection with the dielectric behaviour of the material matrix. In addition, we also investigated whether the anaerobic digestion of sewage sludge, as a bio-energy production method can be monitored by measuring certain dielectric properties. The experimental results revealed that there is a strong correlation between the change in SCOD of different types of wastewater sludge that occurs due to the applied pre-treatment methods and the dielectric constant (at f=450 MHz frequency), and we also found connection between the nascent biogas yield and the dielectric behaviour of the fermentation medium

    Water footprint: A new approach for a more sustainable future

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    Sustainability of water use has got into focus recently, as availability of fresh water resources is under depletion. Population growth, extreme weather conditions (drought), increasing global meat demand all results in higher water consumption of humanity and ecosystem. Water footprint is a promising indicator, which assesses both qualitative and quantitative deterioration of fresh water supplies. By identifying blue, green and grey water components, water use can be assessed in a more comprehensive way. Furthermore impact assessment of different components during production and processing let us identify crucial points of water use, where more efficient solution should be found. As a consequence of a more conscious and sustainable water use assessment considering water footprint, there is a chance, that future generations will inherit fresh water supplies at least in the same condition as we got it from our ancestors.&nbsp

    Enhanced biodegradability of dairy sludge by microwave assisted alkaline and acidic pre-treatments

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    Considering the rapid, volumetric and selective heating effects of microwaves the microwave assisted chemical methods could provide appropriate alternatives for conventional thermal methods in sludge processing. Microwave irradiation alone is suitable to accelerate the hydrolysis stage of anaerobic decomposition of sludge resulted in accelerated biogas production rate and in higher biogas yield. Alkaline pre-treatments increase the organic matter solubility and suitable for disintegration of sludge particles. In some study are concluded that acidic conditions help the disintegration of waste activated sludge and assist in the solubilisation of carbohydrates and proteins which led to increased higher biogas production, as well. Beside the promising results related to effects of microwave pre-treatments on anaerobic digestion of sludge there are very few reports on the investigation of combined acidic/alkali-microwave pre-treatment method for food industry originated sludge. Hence, our study focused on the examination of the effects of combined microwave-alkali and microwave-acidic pre-treatment on aerobic and anaerobic biodegradability of sludge produced in dairy industry Our experimental results verified, that microwave irradiation with alkaline dosage improve the solubility of organic matters in the pH range of 8-12. But enhancement of disintegration was not correlated linearly with biodegradability. During pre-treatment stage, applying pH over 10, the aerobic biodegradability show decreasing tendency. Applying of acidic condition during microwave irradiation resulted in lower disintegration degree than obtained for microwave-alkaline sludge pre-treatment method. But with microwave assisted acidic pre-treatments a higher aerobic biodegradability could be achieved than with alkaline dosage. In microwave pre-treatments acidic condition was preferable to increase the shorter aerobic biodegradability; the alkaline condition was favourable to intensify the anaerobic digestion process
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